Corante

About this Author
Derek Lowe
Derek Lowe, an Arkansan by birth, got his BA from Hendrix College and his PhD in organic chemistry from Duke before spending time in Germany on a Humboldt Fellowship on his post-doc. He's worked for several major pharmaceutical companies since 1989 on drug discovery projects against schizophrenia, Alzheimer's, diabetes, osteoporosis and other diseases. To contact Derek email him directly: derekb.lowe@gmail.com Twitter: Dereklowe

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May 16, 2013

The Atlantic on Drug R&D

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Posted by Derek

"Can you respond to this tripe?" asked one of the emails that sent along this article in The Atlantic. I responded that I was planning to, but that things were made more complicated by my being extensively quoted in said tripe. Anyway, here goes.

The article, by Brian Till of the New America Foundation, seems somewhat confused, and is written in a confusing manner. The title is "How Drug Companies Keep Medicine Out of Reach", but the focus is on neglected tropical diseases, not all medicine. Well, the focus is actually on a contested WHO treaty. But the focus is also on the idea of using prizes to fund research, and on the patent system. And the focus is on the general idea of "delinking" R&D from sales in the drug business. Confocal prose not having been perfected yet, this makes the whole piece a difficult read, because no matter which of these ideas you're waiting to hear about, you end up having a long wait while you work your way through the other stuff. There are any number of sentences in this piece that reference "the idea" and its effects, but there is no sentence that begins with "Here's the idea"

I'll summarize: the WHO treaty in question is as yet formless. There is no defined treaty to be debated; one of the article's contentions is that the US has blocked things from even getting that far. But the general idea is that signatory states would commit to spending 0.01% of GDP on neglected diseases each year. Where this money goes is not clear. Grants to academia? Setting up new institutes? Incentives to commercial companies? And how the contributions from various countries are to be managed is not clear, either: should Angola (for example) pool its contributions with other countries (or send them somewhere else outright), or are they interested in setting up their own Angolan Institute of Tropical Disease Research?

The fuzziness continues. You will read and read through the article trying to figure out what happens next. The "delinking" idea comes in as a key part of the proposed treaty negotiations, with the reward for discovery of a tropical disease treatment coming from a prize for its development, rather than patent exclusivity. But where that money comes from (the GDP-linked contributions?) is unclear. Who sets the prize levels, at what point the money is awarded, who it goes to: hard to say.

And the "Who it goes to" question is a real one, because the article says that another part of the treaty would be a push for open-source discovery on these diseases (Matt Todd's malaria efforts at Sydney are cited). This, though, is to a great extent a whole different question than the source-of-funds one, or the how-the-prizes-work one. Collaboration on this scale is not easy to manage (although it might well be desirable) and it can end up replacing the inefficiencies of the marketplace with entirely new inefficiencies all its own. The research-prize idea seems to me to be a poor fit for the open-collaboration model, too: if you're putting up a prize, you're saying that competition between different groups will spur them on, which is why you're offering something of real value to whoever finishes first and/or best. But if it's a huge open-access collaboration, how do you split up the prize, exactly?

At some point, the article's discussion of delinking R&D and the problems with the current patent model spread fuzzily outside the bounds of tropical diseases (where there really is a market failure, I'd say) and start heading off into drug discovery in general. And that's where my quotes start showing up. The author did interview me by phone, and we had a good discussion. I'd like to think that I helped emphasize that when we in the drug business say that drug discovery is hard, that we're not just putting on a show for the crowd.

But there's an awful lot of "Gosh, it's so cheap to make these drugs, why are they so expensive?" in this piece. To be fair, Till does mention that drug discovery is an expensive and risky undertaking, but I'm not sure that someone reading the article will quite take on board how expensive and how risky it is, and what the implications are. There's also a lot of criticism of drug companies for pricing their products at "what the market will bear", rather than as some percentage of what it cost to discover or make them. This is a form of economics I've criticized many times here, and I won't go into all the arguments again - but I will ask:what other products are priced in such a manner? Other than what customers will pay for them? Implicit in these arguments is the idea that there's some sort of reasonable, gentlemanly profit that won't offend anyone's sensibilities, while grasping for more than that is just something that shouldn't be allowed. But just try to run an R&D-driven business on that concept. I mean, the article itself details the trouble that Eli Lilly, AstraZeneca, and others are facing with their patent expirations. What sort of trouble would they be in if they'd said "No, no, we shouldn't make such profits off our patented drugs. That would be indecent." Even with those massive profits, they're in trouble.

And that brings up another point: we also get the "Drug companies only spend X pennies per dollar on R&D". That's the usual response to pointing out situations like Lilly's; that they took the money and spent it on fleets of yachts or something. The figure given in the article is 16 cents per dollar of revenue, and it's prefaced by an "only". Only? Here, go look at different industries, around the world, and find one that spends more. By any industrial standard, we are plowing massive amounts back into the labs. I know that I complain about companies doing things like stock buybacks, but that's a complaint at the margin of what is already pretty impressive spending.

To finish up, here's one of the places I'm quoted in the article:

I asked Derek Lowe, the chemist and blogger, for his thoughts on the principle of delinking R&D from the actual manufacture of drugs, and why he thought the industry, facing such a daunting outlook, would reject an idea that could turn fallow fields of research on neglected diseases into profitable ones. "I really think it could be viable," he said. "I would like to see it given a real trial, and neglected diseases might be the place to do it. As it is, we really already kind of have a prize model in the developed countries, market exclusivity. But, at the same time, you could look at it and it will say, 'You will only make this amount of money and not one penny more by curing this tropical disease.' Their fear probably is that if that model works great, then we'll move on to all the other diseases."

What you're hearing is my attempt to bring in the real world. I think that prizes are, in fact, a very worthwhile thing to look into for market failures like tropical diseases. There are problems with the idea - for one thing, the prize payoff itself, compared with the time and opportunity cost, is hard to get right - but it's still definitely worth thinking about. But what I was trying to tell Brian Till was that drug companies would be worried (and rightly) about the extension of this model to all other disease areas. Wrapped up in the idea of a research-prize model is the assumption that someone (a wise committee somewhere) knows just what a particular research result is worth, and can set the payout (and afterwards, the price) accordingly. This is not true.

There's a follow-on effect. Such a wise committees might possibly feel a bit of political pressure to set those prices down to a level of nice and cheap, the better to make everyone happy. Drug discovery being what it is, it would take some years before all the gears ground to a halt, but I worry that something like this might be the real result. I find my libertarian impulses coming to the fore whenever I think about this situation, and that prompts me to break out an often-used quote from Robert Heinlein:

Throughout history, poverty is the normal condition of man. Advances which permit this norm to be exceeded — here and there, now and then — are the work of an extremely small minority, frequently despised, often condemned, and almost always opposed by all right-thinking people. Whenever this tiny minority is kept from creating, or (as sometimes happens) is driven out of a society, the people then slip back into abject poverty.

This is known as "bad luck."

Comments (44) + TrackBacks (0) | Category: Drug Development | Drug Prices | Why Everyone Loves Us

April 2, 2013

Tecfidera's Price

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Posted by Derek

Let us take up the case of Tecfidera, the new Biogen/Idec drug for multiple sclerosis, known to us chemists as dimethyl fumarate. It joins the (not very long) list of industrial chemicals (the kind that can be purchased in railroad-car sizes) that are also approved pharmaceuticals for human use. The MS area has seen this before, interestingly.

A year's supply of Tecfidera will set you (or your insurance company) back $54,900. That's a bit higher than many analysts were anticipating, but that means "a bit higher over $50,000". The ceiling is about $60,000, which is what Novartis's Gilenya (fingolomod) goes for, and Biogen wanted to undercut them a bit. So, 55 long ones for a year's worth of dimethyl fumarate pills - what should one think about that?

Several thoughts come to mind, the first one being (probably) "Fifty thousand dollars for a bunch of dimethyl fumarate? Who's going to stand for that?" But we have an estimate for the second part of that question - Biogen thinks that quite a few people are going to stand for it, rather than stand for fingolomod. I'm sure they've devoted quite a bit of time and effort into thinking about that price, and that it's their best estimate of maximum profit. How, exactly, do they get away with that? Simple. They get away with it because they were willing to take the compound through clinical trials in MS patients, find out if it's tolerated and if it's efficacious, figure out the dosing regimen, and get it approved for this use by the FDA. If you or I had been willing to do that, and had been able to round up the money and resources, then we would also have the ability to charge fifty grand a year for it (or whatever we thought fit, actually).

What, exactly, gave them the idea that dimethyl fumarate might be good for multiple sclerosis? As it turns out, a German physician described its topical use for psoriasis back in 1959, and a formation of the compound as a cream (along with some monoesters) was eventually studied clinically by a small company in Switzerland called Fumapharm. This went on the market in Germany in the early 1990s, but the company did not have either the willingness or desire to extend their idea outside that region. But since dimethyl fumarate appears to work on psoriasis by modulating the immune system somehow, it did occur to someone that it might also be worth looking at in multiple sclerosis. Biogen began developing dimethyl fumarate for that purpose with Fumapharm, and eventually bought them outright in 2006 as things began to look more promising.

In other words, the connection of dimethyl fumarate as a possible therapy for MS had been out there, waiting to be made, since before many of us were born. Generations of drug developers had their chances to see it. Every company in the business had a chance to get interested in Fumapharm back in the late 80s and early 90s. But Biogen did, and in 2013 that move has paid off.

Now we come to two more questions, the first of which is "Should that move be paying off quite so lucratively?" But who gets to decide? Watching people pay fifty grand for a year's supply of dimethyl fumarate is not, on the face of it, a very appealing sight. At least, I don't find it so. But on the other hand, cost-of-goods is (for small molecules) generally not a very large part of the expense of a given pill - a rule of thumb is that such expenses should certainly be below 5% of a drug's selling price, and preferably less than 2%. It's just that it's even less in this case, and Biogen also has fewer worries about their supply chain, presumably. The fact this this drug is dimethyl fumarate is a curiosity (and perhaps an irritating one), but that lowers Biogen's costs by a couple of thousand a year per patient compared to some other small molecule. The rest of the cost of Tecfidera has nothing to do with what the ingredients are - it's all about what Biogen had to pay to get it on the market, and (most importantly) what the market will bear. If insurance companies believe that paying fifty thousand a year for the drug is a worthwhile expense, the Biogen will agree with them, too.

The second question is divorced from words like "should", and moves to the practical question of "can". The topical fumarate drug in Europe apparently had fairly wide "homebrew" use among psoriasis patients in other countries, and one has to wonder just a bit about that happening with Tacfidera. Biogen Idec certainly has method-of-use patents, but not composition-of-matter, so it's going to be up to them to try to police this. I found the Makena situation more irritating than this one (and the colchicine one, too), because in those cases, the exact drugs for the exact indications had already been on the market. (Dimethyl fumarate was not a drug for MS until Biogen proved it so, by contrast). But KV Pharmaceuticals had to go after people who were compounding the drug, anyway, and I have to wonder if a secondary market in dimethyl fumarate might develop. I don't know the details of its formulation (and I'm sure that Biogen will make much of it being something that can't be replicated in a basement), but there will surely be people who try it.

Comments (46) + TrackBacks (0) | Category: Drug Development | Drug Prices | The Central Nervous System

March 29, 2013

Sirtuins Live On at GSK

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Posted by Derek

Well, GSK is shutting down the Sirtris operation in Cambridge, but sirtuins apparently live on. I'm told that the company is advertising for chemists and biologists to come to Pennsylvania to staff the effort, and in this market, they'll have plenty of takers. We'll have the sirtuin drug development saga with us for a while yet. And I'm glad, actually, and no, not just because it gives me something to write about. I'd like to know what sirtuins actually are capable of doing in humans, and I'd like to see a drug or two come out of this. What the odds of that are, though, I couldn't say. . .

Comments (18) + TrackBacks (0) | Category: Drug Development

March 27, 2013

A Therapy Named After You?

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Posted by Derek

Back last fall I wrote about Prof. Magnus Essand and his oncoloytic virus research. He's gotten a good amount of press coverage, and has been trying all sorts of approaches to get further work funded. But here's one that I hadn't thought of: Essand and his co-workers are willing to name the therapy after anyone who can pony up the money to get it into a 20-patient human trial.

The more I think about that, the less problem I have with it. This looks at first like a pure angel investor move, and if people want to take a crack at something like this with their own cash, let them do the due diligence and make the call. Actually, Essand believes that his current virus is unpatentable (due to prior publication), so this is less of an a angel investment and more sheer philanthropy. But I have no objections at all to that, either.

Update: here's more on the story.

Comments (11) + TrackBacks (0) | Category: Cancer | Clinical Trials | Drug Development

The DNA-Encoded Library Platform Yields A Hit

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Posted by Derek

I wrote here about DNA-barcoding of huge (massively, crazily huge) combichem libraries, a technology that apparently works, although one can think of a lot of reasons why it shouldn't. This is something that GlaxoSmithKline bought by acquiring Praecis some years ago, and there are others working in the same space.

For outsiders, the question has long been "What's come out of this work?" And there is now at least one answer, published in a place where one might not notice it: this paper in Prostaglandins and Other Lipid Mediators. It's not a journal whose contents I regularly scan. But this is a paper from GSK on a soluble epoxide hydrolase inhibitor, and therein one finds:

sEH inhibitors were identified by screening large libraries of drug-like molecules, each attached to a DNA “bar code”, utilizing DNA-encoded library technology [10] developed by Praecis Pharmaceuticals, now part of GlaxoSmithKline. The initial hits were then synthesized off of DNA, and hit-to-lead chemistry was carried out to identify key features of the sEH pharmacophore. The lead series were then optimized for potency at the target, selectivity and developability parameters such as aqueous solubility and oral bioavailability, resulting in GSK2256294A. . .

That's the sum of the med-chem in the article, which certainly compresses things, and I hope that we see a more complete writeup at some point from a chemistry perspective. Looking at the structure, though, this is a triaminotriazine-derived compound (as in the earlier work linked to in the first paragraph), so yes, you apparently can get interesting leads that way. How different this compound is from the screening hit is a good question, but it's noteworthy that a diaminotriazine's worth of its heritage is still present. Perhaps we'll eventually see the results of the later-generation chemistry (non-triazine).

Comments (12) + TrackBacks (0) | Category: Chemical Biology | Chemical News | Drug Assays | Drug Development

The NIH, Pfizer, and Senator Wyden

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Posted by Derek

Senator Ron Wyden (D-Oregon) seems to be the latest champion of the "NIH discovers drugs and Pharma rips them off" viewpoint. Here's a post from John LaMattina on Wyden's recent letter to Francis Collins. The proximate cause of all this seems to be the Pfizer JAK3 inhibitor:

Tofacitinib (Xeljanz), approved last November by the U.S. Food and Drug Administration, is nearing the market as the first oral medication for the treatment of rheumatoid arthritis. Given that the research base provided by the National Institutes of Health (NIH) culminated in the approval of Xeljanz, citizens have the right to be concerned about the determination of its price and what return on investment they can expect. While it is correct that the expenses of drug discovery and preclinical and clinical development were fully undertaken by Pfizer, taxpayer-funded research was foundational to the development of Xeljanz.

I think that this is likely another case where people don't quite realize the steepness of the climb between "X looks like a great disease target" and "We now have an FDA-approved drug targeting X". Here's more from Wyden's letter:

Developing drugs in America remains a challenging business, and NIH plays a critically important role by doing research that might not otherwise get done by the private sector. My bottom line: When taxpayer-funded research is commercialized, the public deserves a real return on its investment. With the price of Xeljanz estimated at about $25,000 a year and annual sales projected by some industry experts as high as $2.5 billion, it is important to consider whether the public investment has assured accessibility and affordability.

This is going to come across as nastier than I intend it to, but my first response is that the taxpayer's return on this was that they got a new drug where there wasn't one before. And via the NIH-funded discoveries, the taxpayers stimulated Pfizer (and many other companies) to spend huge amounts of money and effort to turn the original discoveries in the JAK field into real therapies. I value knowledge greatly, but no human suffering whatsoever was relieved by the knowledge alone that JAK3 appeared to play a role in inflammation. What was there was the potential to affect the lives of patients, and that potential was realized by Pfizer spending its own money.

And not just Pfizer. Let's not forget that the NIH entered into research agreements with many other companies, and that the list of JAK3-related drug discovery projects is a long one. And keep in mind that not all of them, by any means, have ever earned a nickel for the companies involved, and that many of them never will. As for Pfizer, Xeljanz has been on the market for less than six months, so it's too early to say how the drug will do. But it's not a license to print money, and is in a large, extremely competitive market. And should it run into trouble (which I certainly hope doesn't happen), I doubt if Senator Wyden will be writing letters seeking to share some of the expenses.

Comments (35) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Development | Drug Prices | Regulatory Affairs

March 26, 2013

Automated Med-Chem, At Last?

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Posted by Derek

I've written several times about flow chemistry here, and a new paper in J. Med. Chem. prompts me to return to the subject. This, though, is the next stage in flow chemistry - more like flow med-chem:

Here, we report the application of a flow technology platform integrating the key elements of structure–activity relationship (SAR) generation to the discovery of novel Abl kinase inhibitors. The platform utilizes flow chemistry for rapid in-line synthesis, automated purification, and analysis coupled with bioassay. The combination of activity prediction using Random-Forest regression with chemical space sampling algorithms allows the construction of an activity model that refines itself after every iteration of synthesis and biological result.

Now, this is the point at which people start to get either excited or fearful. (I sometimes have trouble telling the difference, myself). We're talking about the entire early-stage optimization cycle here, and the vision is of someone topping up a bunch of solvent reservoirs, hitting a button, and leaving for the weekend in the expectation of finding a nanomolar compound waiting on Monday. I'll bet you could sell that to AstraZeneca for some serious cash, and to be fair, they're not the only ones who would bite, given a sufficiently impressive demo and slide deck.

But how close to this Lab of the Future does this work get? Digging into the paper, we have this:

Initially, this approach mirrors that of a traditional hit-to-lead program, namely, hit generation activities via, for example, high-throughput screening (HTS), other screening approaches, or prior art review. From this, the virtual chemical space of target molecules is constructed that defines the boundaries of an SAR heat map. An initial activity model is then built using data available from a screening campaign or the literature against the defined biological target. This model is used to decide which analogue is made during each iteration of synthesis and testing, and the model is updated after each individual compound assay to incorporate the new data. Typically the coupled design, synthesis, and assay times are 1–2 h per iteration.

Among the key things that already have to be in place, though, are reliable chemistry (fit to generate a wide range of structures) and some clue about where to start. Those are not givens, but they're certainly not impossible barriers, either. In this case, the team (three UK groups) is looking for BCL-Abl inhibitors, a perfectly reasonable test bed. A look through the literature suggested coupling hinge-binding motifs to DFG-loop binders through an acetylene linker, as in Ariad's ponatinib. This, while not a strategy that will earn you a big raise, is not one that's going to get you fired, either. Virtual screening around the structure, followed by eyeballing by real humans, narrowed down some possibilities for new structures. Further possibilities were suggested by looking at PDB structures of homologous binding sites and seeing what sorts of things bound to them.

So already, what we're looking at is less Automatic Lead Discovery than Automatic Patent Busting. But there's a place for that, too. Ten DFG pieces were synthesized, in Sonogashira-couplable form, and 27 hinge-binding motifs with alkynes on them were readied on the other end. Then they pressed the button and went home for the weekend. Well, not quite. They set things up to try two different optimization routines, once the compounds were synthesized, run through a column, and through the assay (all in flow). One will be familiar to anyone who's been in the drug industry for more than about five minutes, because it's called "Chase Potency". The other one, "Most Active Under Sampled", tries to even out the distributions of reactants by favoring the ones that haven't been used as often. (These strategies can also be mixed). In each case, the model was seeded with binding constants of literature structures, to get things going.

The first run, which took about 30 hours, used the "Under Sampled" algorithm to spit out 22 new compounds (there were six chemistry failures) and a corresponding SAR heat map. Another run was done with "Chase Potency" in place, generating 14 more compounds. That was followed by a combined-strategy run, which cranked out 28 more compounds (with 13 failures in synthesis). Overall, there were 90 loops through the process, producing 64 new products. The best of these were nanomolar or below.

But shouldn't they have been? The deck already has to be stacked to some degree for this technique to work at all in the present stage of development. Getting potent inhibitors from these sorts of starting points isn't impressive by itself. I think the main advantage to this is the time needed to generated the compound and the assay data. Having the synthesis, purification, and assay platform all right next to each other, with compound being pumped right from one to the other, is a much tighter loop than the usual drug discovery organization runs. The usual, if you haven't experienced it, is more like "Run the reaction. Work up the reaction. Run it through a column (or have the purification group run it through a column for you). Get your fractions. Evaporate them. Check the compound by LC/MS and NMR. Code it into the system and get it into a vial. Send it over to the assay folks for the weekly run. Wait a couple of days for the batch of data to be processed. Repeat."

The science-fictional extension of this is when we move to a wider variety of possible chemistries, and perhaps incorporate the modeling/docking into the loop as well, when it's trustworthy enough to do so. Now that would be something to see. You come back in a few days and find that the machine has unexpectedly veered off into photochemical 2+2 additions with a range of alkenes, because the Chase Potency module couldn't pass up a great cyclobutane hit that the modeling software predicted. And all while you were doing something else. And that something else, by this point, is. . .what, exactly? Food for thought.

Comments (16) + TrackBacks (0) | Category: Chemical News | Drug Assays | Drug Development

March 21, 2013

AstraZeneca Makes a Deal With Moderna. Wait, Who?

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Posted by Derek

AstraZeneca has announced another 2300 job cuts, this time in sales and administration. That's not too much of a surprise, as the cuts announced recently in R&D make it clear that the company is determined to get smaller. But their overall R&D strategy is still unclear, other than "We can't go on like this", which is clear enough.

One interesting item has just come out, though. The company has done a deal with Moderna Therapeutics of Cambridge (US), a relatively new outfit that's trying something that (as far as I know) no one else has had the nerve to. Moderna is trying to use messenger RNAs as therapies, to stimulate the body's own cells to produce more of some desired protein product. This is the flip side of antisense and RNA interference, where you throw a wrench into the transcription/translation machinery to cut down on some protein. Moderna's trying to make the wheels spin in the other direction.

This is the sort of idea that makes me feel as if there are two people inhabiting my head. One side of me is very excited and interested to see if this approach will work, and the other side is very glad that I'm not one of the people being asked to do it. I've always thought that messing up or blocking some process was an easier task than making it do the right thing (only more so), and in this case, we haven't even reliably shown that blocking such RNA pathways is a good way to a therapy.

I also wonder about the disease areas that such a therapy would treat, and how amenable they are to the approach. The first one that occurs to a person is "Allow Type I diabetics to produce their own insulin", but if your islet cells have been disrupted or killed off, how is that going to work? Will other cell types recognize the mRNA-type molecules you're giving, and make some insulin themselves? If they do, what sort of physiological control will they be under? Beta-cells, after all, are involved in a lot of complicated signaling to tell them when to make insulin and when to lay off. I can also imagine this technique being used for a number of genetic disorders, where we know what the defective protein is and what it's supposed to be. But again, how does the mRNA get to the right tissues at the right time? Protein expression is under so many constraints and controls that it seems almost foolhardy to think that you could step in, dump some mRNA on the process, and get things to work the way that you want them to.

But all that said, there's no substitute for trying it out. And the people behind Moderna are not fools, either, so you can be sure that these questions (and many more) have crossed their minds already. (The company's press materials claim that they've addressed the cellular-specificity problem, for example). They've gotten a very favorable deal from AstraZeneca - admittedly a rather desperate company - but good enough that they must have a rather convincing story to tell with their internal data. This is the very picture of a high-risk, high-reward approach, and I wish them success with it. A lot of people will be watching very closely.

Comments (37) + TrackBacks (0) | Category: Biological News | Business and Markets | Drug Development

March 19, 2013

Affymax In Trouble

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Posted by Derek

Affymax has had a long history, and it's rarely been dull. The company was founded in 1988, back in the very earliest flush of the Combichem era, and in its early years it (along with Pharmacopeia) was what people thought of when they thought of that whole approach. Huge compound libraries produced (as much as possible) by robotics, equally huge screening efforts to deal with all those compounds - this stuff is familiar to us now (all too familiar, in many cases), but it was new then. If you weren't around for it, you'll have to take the word of those who were that it could all be rather exciting and scary at first: what if the answer really was to crank out huge piles of amides, sulfonamides, substituted piperazines, aminotriazines, oligopeptides, and all the other "build-that-compound-count-now!" classes? No one could say for sure that it wasn't. Not yet.

Glaxo bought Affymax back in 1995, about the time they were buying Wellcome, which makes it seem like a long time ago, and perhaps it was. At any rate, they kept the combichem/screening technology and spun a new version of Affymax back out in 2001 to a syndicate of investors. For the past twelve years, that Affymax has been in the drug discovery and development business on its own.

And as this page shows, the story through most of those years has been peginesatide (brand name Omontys, although it was known as Hematide for a while as well). This is synthetic peptide (with some unnatural amino acids in it, and a polyethylene glycol tail) that mimics erythropoetin. What with its cyclic nature (a couple of disulfide bonds), the unnatural residues, and the PEGylation, it's a perfect example of what you often have to do to make an oligopeptide into a drug.

But for quite a while there, no one was sure whether this one was going to be a drug or not. Affymax had partnered with Takeda along the way, and in 2010 the companies announced some disturbing clinical data in kidney patients. While Omontys did seem to help with anemia, it also seemed to have a worse safety profile than Amgen's EPO, the existing competition. The big worry was cardiovascular trouble (which had also been a problem with EPO itself and all the other attempted competition in that field). A period of wranging ensued, with a lot of work on the clinical data and a lot of back-and-forthing with the FDA. In the end, the drug was actually approved one year ago, albeit with a black-box warning about cardiovascular safety.

But over the last year, about 25,000 patients got the drug, and unfortunately, 19 of them had serious anaphylactic reactions to it within the first half hour of exposure. Three patients died as a result, and some others nearly did. That is also exactly what one worries about with a synthetic peptide derivative: it's close enough to the real protein to do its job, but it's different enough to set off the occasional immune response, and the immune system can be very serious business indeed. Allergic responses had been noted in the clinical trials, but I think that if you'd taken bets last March, people would have picked the cardiovascular effects as the likely nemesis, not anaphylaxis. But that's not how it's worked out.

Takeda and Affymax voluntarily recalled the drug last month. And that looked like it might be all for the company, because this has been their main chance for some years now. Sure enough, the announcement has come that most of the employees are being let go. And it includes this language, which is the financial correlate of Cheyne-Stokes breathing:

The company also announced that it will retain a bank to evaluate strategic alternatives for the organization, including the sale of the company or its assets, or a corporate merger. The company is considering all possible alternatives, including further restructuring activities, wind-down of operations or even bankruptcy proceedings.

I'm sorry to hear it. Drug development is very hard indeed.

Comments (11) + TrackBacks (0) | Category: Business and Markets | Cardiovascular Disease | Drug Development | Drug Industry History | Toxicology

March 18, 2013

GlaxoSmithKline's CEO on the Price of New Drugs

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Posted by Derek

Well, GlaxoSmithKline CEO Andrew Witty has made things interesting. Here he is at a recent conference in London when the topic of drug pricing came up:

. . . Witty said the $1 billion price tag was "one of the great myths of the industry", since it was an average figure that includes money spent on drugs that ultimately fail.

In the case of GSK, a major revamp in the way research is conducted means the rate of return on R&D investment has increased by about 30 percent in the past three or four years because fewer drugs have flopped in late-stage testing, he said.

"If you stop failing so often you massively reduce the cost of drug development ... it's why we are beginning to be able to price lower," Witty said.

"It's entirely achievable that we can improve the efficiency of the industry and pass that forward in terms of reduced prices."

I have a feeling that I'm going to be hearing "great myths of the industry" in my email for some time, thanks to this speech, so I'd like to thank Andrew Witty for that. But here's what he's trying to get across: if you start research on for a new drug, name a clinical candidate, take it to human trials and are lucky enough to have it work, then get it approved by the FDA, you will not have spent one billion dollars to get there. That, though, is the figure for a single run-through when everything works. If, on the other hand, you are actually running a drug company, with many compounds in development, and after a decade or so you total up all the money you've spent, versus the number of drugs you got onto the market, well, then you may well average a billion dollars per drug. That's because so many of them wipe out in the clinic; the money gets spent and you get no return at all.

That's the analysis that Matthew Herper did here (blogged about here), and that same Reuters article makes reference to a similar study done by Deloitte (and Thomson Reuters!) that found that the average cost of a new drug is indeed about $1.1 billion when you have to pay for the failures.

And believe me, we have to pay for them. A lottery ticket may only cost a dollar, but by the time you've won a million dollars playing the lottery, you will have bought a lot of losing tickets. In fact, you'll have bought far more than a million dollar's worth, or no state would run a lottery, but that's a negative-expectations game, while drug research (like any business) is supposed to be positive-expectations. Is it? Just barely, according to that same Deloitte study:

In effect, the industry is treading water in the fight to deliver better returns on the billions of dollars ploughed into the hunt for new drugs each year.

With an average internal rate of return (IRR) from R&D in 2012 of 7.2 percent - against 7.7 percent and 10.5 percent in the two preceding years - Big Pharma is barely covering its average cost of capital, estimated at around 7 percent.

Keep that in mind next time you hear about how wonderfully profitable the drug business is. And those are still better numbers than Morgan Stanley had a couple of years before, when they estimated that our internal returns probably weren't keeping up with our cost of capital at all. (Mind you, it seems that their analysis may have been a bit off, since they used their figures to recommend an "Overweight" on AstraZeneca shares, a decision that looked smart for a few months, but one that a person by now would have regretted deeply).

But back to Andrew Witty. What he's trying to say is that it doesn't have to cost a billion dollars per drug, if you don't fail so often, and he's claiming that GSK is starting to fail less often. True, or not? The people I know at the company aren't exactly breaking out the party hats, for what that's worth, and it looks like the company's might have to add the entire Sirtris investment to the "sunk cost" pile. Overall, I think it's too soon to call any corners as having been turned, even if GSK does turn out to have been doing better. Companies can have runs of good fortune and bad, and the history of the industry is absolutely littered with the press releases of companies who say that they've Turned A New Page of Success and will now be cranking out the wonder drugs like nobody's business. If they keep it up, GSK will have plenty of chances to tell us all about it.

Now, one last topic. What about Witty's statement that this new trend to success will allow drug prices themselves to come down? That's worth thinking about all by itself, on several levels - here are my thoughts, in no particular order:

(1) To a first approximation, that's true. If you're selling widgets, your costs go down, you can cut prices, and you can presumably sell more widgets. But as mentioned above, I'm not yet convinced that GSK's costs are truly coming down yet. And see point three below, because GSK and the rest of us in this business are not, in fact, selling widgets.

(2) Even if costs are coming down, counterbalancing that are several other long-term trends, such as the low-hanging fruit problem. As we move into harder and harder sorts of targets and disease areas, I would assume that the success rate of drugs in the clinic will be hard pressed to improve. This is partly a portfolio management problem, and can be ameliorated and hedged against to some degree, but it is, I think, a long-term concern, unless we start to make some intellectual headway on these topics, and speed the day. On the other side of this balance are the various efforts to rationalize clinical trials and so on.

(3) A larger factor is that the market for innovative drugs is not very sensitive to price. This is a vast topic, covered at vast length in many places, but it comes down to there being (relatively) few entrants in any new therapeutic space, and to people, and governments, and insurance companies, being willing to spend relatively high amounts of money for human health. (The addition of governments into that list means also that various price-fixing schemes distort the market in all kinds of interesting ways as well). At any rate, price mechanisms don't work like classical econ-textbook widgets in the drug business.

So I'm not sure, really, how this will play out. GSK has only modest incentives to lower the prices of its drugs. Such a move won't, in many markets, allow them to sell more drugs to make up the difference on volume. And actually, the company will probably be able to offset some of the loss via the political capital that comes from talking about any such price changes. We might be seeing just that effect with Witty's speech.

Comments (30) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Prices

March 14, 2013

Does Baldness Get More Funding Than Malaria?

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Posted by Derek

OK, let's fact-check Bill Gates today, shall we?

Capitalism means that there is much more research into male baldness than there is into diseases such as malaria, which mostly affect poor people, said Bill Gates, speaking at the Royal Academy of Engineering's Global Grand Challenges Summit.

"Our priorities are tilted by marketplace imperatives," he said. "The malaria vaccine in humanist terms is the biggest need. But it gets virtually no funding. But if you are working on male baldness or other things you get an order of magnitude more research funding because of the voice in the marketplace than something like malaria."

Gates' larger point, that tropical diseases are an example of market failure, stands. But I don't think this example does. I have never yet worked on any project in industry that had anything to do with baldness, while I have actually touched on malaria. Looking around the scientific literature, I see many more publications on potential malaria drugs than I see potential baldness drugs (in fact, I'm not sure if I've ever seen anything on the latter, after minoxidil - and its hair-growth effects were discovered by accident during a cardiovascular program). Maybe I'm reading the wrong journals.

But then, Gates also seems to buy into the critical-shortage-of-STEM idea:

With regards to encouraging more students into STEM education, Gates said: "It's kind of surprising that we have such a deficit of people going into those fields. Look at where you can have the most interesting job that pays well and will have impact on society -- all three of those things line up to say science and engineering and yet in most rich countries we see decline. Asia is an exception."

The problem is, there aren't as many of these interesting, well-paying jobs around as there used to be. Any discussion of the STEM education issue that doesn't deal with that angle is (to say the least) incomplete.

Comments (28) + TrackBacks (0) | Category: Drug Development | Drug Industry History | Infectious Diseases

March 13, 2013

Who to Manufacture an API?

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Posted by Derek

Here's a very practical question indeed, sent in by a reader:

After a few weeks of trying to run down a possible API manufacturer for our molecule, I am stuck. We have a straightforward proven synthesis of a 300 weight lipid and need only 10 kg for our trials. Any readers have suggestions? Alternately, we will do it ourselves and find someone to help us with the documentation. Suggestions that way, too?

That's worth asking: who's your go-to for things like this, a reliable contract supplier for high-quality material with all the documentation? I'll say up front that I don't know who's been contacted already, or why the search has been as difficult as it has, but I'll see if I can get more details. Suggestions welcome in the comments. . .

Update: this post has generated a lot of very sound advice. Anyone who's approaching this stage for the first time (as my correspondent clearly is) is looking at a significant expenditure for something that could make or break a small research effort. I'm putting this note up for people who find this post in future searches - read the comments; you'll be glad you did.

Comments (65) + TrackBacks (0) | Category: Drug Development

Getting Down to Protein-Protein Compounds

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Posted by Derek

Late last year I wrote about a paper that suggested that some "stapled peptides" might not work as well as advertised. I've been meaning to link to this C&E News article on the whole controversy - it's a fine overview of the area.

And that also gives me a chance to mention this review in Nature Chemistry (free full access). It's an excellent look at the entire topic of going after alpha-helix protein-protein interactions with small molecules. Articles like this really give you an appreciation for a good literature review - this information is scattered across the literature, and the authors here (from Leeds) have really done everyone interested in this topic a favor by collecting all of it and putting it into context.

As they say, you really have two choices if you're going after this sort of protein-protein interaction (well, three, if you count chucking the whole business and going to truck-driving school, but that option is not specific to this field). You can make something that's helical itself, so as to present the side chains in what you hope will be the correct orientation, or you can go after some completely different structure that just happens to arrange these groups into the right spots (but has no helical architecture itself).

Neither of these is going to lead to attractive molecules. The authors address this problem near the end of the paper, saying that we may be facing a choice here: make potent inhibitors of protein-protein interactions, or stay within Lipinski-guideline property space. Doing both at the same time just may not be possible. On the evidence so far, I think they're right. How we're going to get such things into cells, though, is a real problem (note this entry last fall on macrocyclic compounds, where the same concern naturally comes up). Since we don't seem to know much about why some compounds make it into cells and some don't, perhaps the way forward (for now) is to find a platform where as many big PPI candidates as possible can be evaluated quickly for activity (both in the relevant protein assay and then in cells). If we can't be smart enough, or not yet, maybe we can go after the problem with brute force.

With enough examples of success, we might be able to get a handle on what's happening. This means, though, that we'll have to generate a lot of complex structures quickly and in great variety, and if that's not a synthetic organic chemistry problem, I'd like to know what is. This is another example of a theme I come back to - that there are many issues in drug discovery that can only be answered by cutting-edge organic chemistry. We should be attacking these and making a case for how valuable the chemical component is, rather than letting ourselves be pigeonholed as a bunch of folks who run Suzuki couplings all day long and who might as well be outsourced to Fiji.

Comments (10) + TrackBacks (0) | Category: Drug Assays | Drug Development | Pharmacokinetics

February 8, 2013

All Those Drug-Likeness Papers: A Bit Too Neat to be True?

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Posted by Derek

There's a fascinating paper out on the concept of "drug-likeness" that I think every medicinal chemist should have a look at. It would be hard to count the number of publications on this topic over the last ten years or so, but what if we've been kidding ourselves about some of the main points?

The big concept in this area is, of course, Lipinski criteria, or Rule of Five. Here's what the authors, Peter Kenny and Carlos Montanari of the University of São Paulo, have to say:

No discussion of drug-likeness would be complete without reference to the influential Rule of 5 (Ro5) which is essentially a statement of property distributions for compounds taken into Phase II clinical trials. The focus of Ro5 is oral absorption and the rule neither quantifies the risks of failure associated with non-compliance nor provides guidance as to how sub-optimal characteristics of compliant compounds might be improved. It also raises a number of questions. What is the physicochemical basis of Ro50s asymmetry with respect to hydrogen bond donors and acceptors? Why is calculated octanol/water partition coefficient (ClogP) used to specify Ro50s low polarity limit when the high polarity cut off is defined in terms of numbers of hydrogen bond donors and acceptors? It is possible that these characteristics reflect the relative inability of the octanol/water partitioning system to ‘see’ donors (Fig. 1) and the likelihood that acceptors (especially as defined for Ro5) are more common than donors in pharmaceutically-relevant compounds. The importance of Ro5 is that it raised awareness across the pharmaceutical industry about the relevance of physico- chemical properties. The wide acceptance of Ro5 provided other researchers with an incentive to publish analyses of their own data and those who have followed the drug discovery literature over the last decade or so will have become aware of a publication genre that can be described as ‘retrospective data analysis of large proprietary data sets’ or, more succinctly, as ‘Ro5 envy’.

There, fellow med-chemists, doesn't this already sound like something you want to read? Thought so. Here, have some more:

Despite widespread belief that control of fundamental physicochemical properties is important in pharmaceutical design, the correlations between these and ADMET properties may not actually be as strong as is often assumed. The mere existence of a trend is of no interest in drug discovery and strengths of trends must be known if decisions are to be accurately described as data-driven. Although data analysts frequently tout the statistical significance of the trends that their analysis has revealed, weak trends can be statistically significant without being remotely interesting. We might be confident that the coin that lands heads up for 51 % of a billion throws is biased but this knowledge provides little comfort for the person charged with predicting the result of the next throw. Weak trends can be beaten and when powered by enough data, even the feeblest of trends acquires statistical significance.

So, where are the authors going with all this entertaining invective? (Not that there's anything wrong with that; I'm the last person to complain). They're worried that the transformations that primary drug property data have undergone in the literature have tended to exaggerate the correlations between these properties and the endpoints that we care about. The end result is pernicious:

Correlation inflation becomes an issue when the results of data analysis are used to make real decisions. To restrict values of properties such as lipophilicity more stringently than is justified by trends in the data is to deny one’s own drug-hunting teams room to maneuver while yielding the initiative to hungrier, more agile competitors.

They illustrate this by reference to synthetic data sets, showing how one can get rather different impressions depending on how the numbers are handled along the way. Representing sets of empirical points by using their average values, for example, can cause the final correlations to appear more robust than they really are. That, the authors say, is just what happened in this study from 2006 ("Can we rationally design promiscuous drugs?) and in this one from 2007 ("The influence of drug-like concepts on decision-making in medicinal chemistry"). The complaint is that showing a correlation between cLogP and median compound promiscuity does not imply that there is one between cLogP and compound promiscuity per se. And the authors note that the two papers manage to come to opposite conclusions about the effect of molecular weight, which does make one wonder. The "Escape from flatland" paper from 2009 and the "ADMET rules of thumb" paper from 2008 (mentioned here) also come in for criticism on this point - binning averaged data from a large continuous set and then treated those as real objects for statistic analysis. Ones conclusions depend strongly on how many bins one uses. Here's a specific take on that last paper:

The end point of the G2008 analysis is ‘‘a set of simple interpretable ADMET rules of thumb’’ and it is instructive to examine these more closely. Two classifications (ClogP<4 and MW<400 Da; ClogP>4 or MW>400 Da) were created and these were combined with the four ionization state classifications to define eight classes of compound. Each combination of ADMET property and compound class was labeled according to whether the mean value of the ADMET property was lower than, higher than or not significantly different from the average for all compounds. Although the rules of thumb are indeed simple, it is not clear how useful they are in drug discovery. Firstly, the rules only say whether or not differences are significant and not how large they are. Secondly, the rules are irrelevant if the compounds of interest are all in the same class. Thirdly, the rules predict abrupt changes in ADMET properties going from one class to another. For example, the rules predict significantly different aqueous solubility for two neutral compounds with MW of 399 and 401 Da, provided that their ClogP values do not exceed 4. It is instructive to consider how the rules might have differed had values of logP and MW of 5 and 500 Da (or 3 and 300 Da) had been used to define them instead of 4 and 400 Da.

These problems also occur in graphical representations of all these data, as you'd imagine, and the authors show several of these that they object to. A particular example is this paper from 2010 ("Getting physical in drug discovery"). Three data sets, whose correlations in their primary data do not vary significantly, generate very different looking bar charts. And that leads to this comment:

Both the MR2009 and HY2010 studies note the simplicity of the relationships that the analysis has revealed. Given that drug discovery would appear to be anything but simple, the simplicity of a drug-likeness model could actually be taken as evidence for its irrelevance to drug discovery. The number of aromatic rings in a molecule can be reduced by eliminating rings or by eliminating aromaticity and the two cases appear to be treated as equivalent in both the MR2009 and HY2010 studies. Using the mnemonic suggested in MR2009 one might expect to make a compound more developable by replacing a benzene ring with cyclohexadiene or benzoquinone.

The authors wind up by emphasizing that they're not saying that things like lipophilicity, aromaticity, molecular weight and so on are unimportant - far from it. What they're saying, though, is that we need to be aware of how strong these correlations really are so that we don't fool ourselves into thinking that we're addressing our problems, when we really aren't. We might want to stop looking for huge, universally applicable sets of rules and take what we can get in smaller, local data sets within a given series of compounds. The paper ends with a set of recommendations for authors and editors - among them, always making primary data sets part of the supplementary material, not relying on purely graphical representations to make statistical points, and a number of more stringent criteria for evaluating data that have been partitioned into bins. They say that they hope that their paper "stimulates debate", and I think it should do just that. It's certainly given me a lot of things to think about!

Comments (13) + TrackBacks (0) | Category: Drug Assays | Drug Development | In Silico | The Scientific Literature

February 7, 2013

Addex Cuts Back: An Old Story, Told Again

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Posted by Derek

Addex Therapeutics has been trying to develop allosteric modulators as drugs. That's a worthy goal (albeit a tough one) - "allosteric" is a term that covers an awful lot of ground. The basic definition is a site that affects the activity of its protein, but is separate from the active or ligand-binding site itself. All sorts of regulatory sites, cofactors, protein-protein interaction motifs, and who knows what else can fit into that definition. It's safe to say that allosteric mechanisms account for a significant number of head-scratching assay results, but unraveling them can be quite a challenge.

It's proving to be one for Addex. They've announced that they're going to focus on a few clinical programs, targeting orphan diseases in the major markets, and to do that, well. . .:

In executing this strategy and to maximize potential clinical success in at least two programs over the next 12 months, the company will reduce its overall cost structure, particularly around its early-stage discovery efforts, while maintaining its core competency and expertise in allosteric modulation. The result will be a development-focused company with a year cash runway. In addition, the company will seek to increase its cash position through non-dilutive partnerships by monetizing its platform capability as well as current discovery programs via licensing and strategic transactions.

That is the sound of the hatches being battened down. And that noise can be heard pretty often in the small-company part of the drug business. Too often, it comes down to "We can advance this compound in the clinic, enough to try to get more money from someone, or we can continue to do discovery research. But not both. Not now." Some companies have gone through this cycles several times, laying off scientists and then eventually hiring people back (sometimes some of the same people) when the money starts flowing again. But in the majority of these cases, I'd say that this turns out to be the beginning of the end. The failure rates in the clinic see to that - if you have to have your compounds work there, the very next ones you have, the only things you have on hand in order to survive, then the odds are not with you.

But that's what every small biopharma company faces: something has to work, or the money will run out. A lot of the managing of such an outfit consists of working out strategies to keep things going long enough. You can start from a better position than usual, if that's an option. You can pursue deals with larger companies early on, if you actually have something that someone might want (but you won't get as good a deal as you would have later, if what you're partnering actually works out). You can beat all sorts of bushes to raise cash, and try all sorts of techniques to keep it from being spent so quickly, or on the wrong things (as much as you can tell what those are).

But eventually, something has to work, or the music stops. Ditching everything except the clinical candidates is one of the last resorts, so I wish Addex good luck, which they (and all of us) will need.

Comments (14) + TrackBacks (0) | Category: Business and Markets | Drug Development

January 25, 2013

CETP, Alzheimer's, Monty Hall, and Roulette. And Goats.

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Posted by Derek

CETP, now there's a drug target that has incinerated a lot of money over the years. Here's a roundup of compounds I posted on back last summer, with links to their brutal development histories. I wondered here about what's going to happen with this class of compounds: will one ever make it as a drug? If it does, will it just end up telling us that there are yet more complications in human lipid handling that we didn't anticipate?

Well, Merck and Lilly are continuing their hugely expensive, long-running atempts to answer these questions. Here's an interview with Merck's Ken Frazier in which he sounds realistic - that is, nervous:

Merck CEO Ken Frazier, speaking in Davos on the sidelines of the World Economic Forum, said the U.S. drugmaker would continue to press ahead with clinical research on HDL raising, even though the scientific case so far remained inconclusive.

"The Tredaptive failure is another piece of evidence on the side of the scale that says HDL raising hasn't yet been proven," he said.

"I don't think by any means, though, that the question of HDL raising as a positive factor in cardiovascular health has been settled."

Tredaptive, of course, hit the skids just last month. And while its mechanism is not directly relevant to CETP inhibition (I think), it does illustrate how little we know about this area. Merck's anacetrapib is one of the ugliest-looking drug candidates I've ever seen (ten fluorines, three aryl rings, no hydrogen bond donors in sight), and Lilly's compound is only slightly more appealing.

But Merck finds itself having to bet a large part of the company's future in this area. Lilly, for its part, is betting similarly, and most of the rest of their future is being plunked down on Alzheimer's. And these two therapeutic areas have a lot in common: they're both huge markets that require huge clinical trials and rest on tricky fundamental biology. The huge market part makes sense; that's the only way that you could justify the amount of development needed to get a compound through. But the rest of the setup is worth some thought.

Is this what Big Pharma has come to, then? Placing larger and larger bets in hopes of a payoff that will make it all work out? If this were roulette, I'd have no trouble diagnosing someone who was using a Martingale betting system. There are a few differences, although I'm not sure how (or if) they cancel out For one thing, the Martingale gambler is putting down larger and larger amounts of money in an attempt to win the same small payout (the sum of the initial bet!) Pharma is at least chasing a larger jackpot. But the second difference is that the house advantage at roulette is a fixed 5.26% (at least in the US), which is ruinous, but is at least a known quantity.

But mentioning "known quantities" brings up a third difference. The rules of casino games don't change (unless an Ed Thorp shows up, which was a one-time situation). The odds of drug discovery are subject to continuous change as we acquire more knowledge; it's more like the Monty Hall Paradox. The question is, have the odds changed enough in CETP (or HDL-raising therapies in general) or Alzheimer's to make this a reasonable wager?

For the former, well, maybe. There are theories about what went wrong with torcetrapib (a slight raising of blood pressure being foremost, last I heard), and Merck's compound seems to be dodging those. Roche's failure with dacetrapib is worrisome, though, since the official reason there was sheer lack of efficacy in the clinic. And it's clear that there's a lot about HDL and LDL that we don't understand, both their underlying biology and their effects on human health when they're altered. So (to put things in terms of the Monty Hall problem), a tiny door has been opened a crack, and we may have caught a glimpse of some goat hair. But it could have been a throw rug, or a gorilla; it's hard to say.

What about Alzheimer's? I'm not even sure if we're learned as much as we have with CETP. The immunological therapies have been hard to draw conclusions from, because hey, it's the immune system. Every antibody is different, and can do different things. But the mechanistic implications of what we've seen so far are not that encouraging, unless, of course, you're giving interviews as an executive of Eli Lilly. The small-molecule side of the business is a bit easier to interpret; it's an unrelieved string of failures, one crater after another. We've learned a lot about Alzheimer's therapies, but what we've mostly learned is that nothing we've tried has worked much. In Monty Hall terms, the door has stayed shut (or perhaps has opened every so often to provide a terrifying view of the Void). At any rate, the flow of actionable goat-delivered information has been sparse.

Overall, then, I wonder if we really are at the go-for-the-biggest-markets-and-hope-for-the-best stage of research. The big companies are the ones with enough resources to tackle the big diseases; that's one reason we see them there. But the other reason is that the big diseases are the only things that the big companies think can rescue them.

Comments (4) + TrackBacks (0) | Category: Alzheimer's Disease | Cardiovascular Disease | Clinical Trials | Drug Development | Drug Industry History

January 24, 2013

Daniel Vasella Steps Down at Novartis

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Posted by Derek

So Daniel Vasella, longtime chairman of Novartis, has announced that he's stepping down. (He'll be replaced by Joerg Reinhardt, ex-Bayer, who was at Novartis before that). Vasella's had a long run. People on the discovery side of the business will remember him especially for the decision to base the company's research in Cambridge, which has led to (or at the very least accelerated the process of) many of the other big companies putting up sites there as well. Novartis is one of the most successful large drug companies in the world, avoiding the ferocious patent expiration woes of Lilly and AstraZeneca, and avoiding the gigantic merger disruptions of many others.

That last part, though, is perhaps an accident. Novartis did buy a good-sized stake in Roche at one point, and has apparently made, in vain, several overtures over the years to the holders of Roche's voting shares (many of whom are named "Hoffman-LaRoche" and live in very nice parts of Switzerland). And Vasella did oversee the 1996 merger between Sandoz and Ciba-Geigy that created Novartis itself, and he wasn't averse to big acquisitions per se, as the 2006 deal to buy Chiron shows.

It's those very deals, though, that have some investors cheering his departure. Reading that article, which is written completely from the investment side of the universe, is quite interesting. Try this out:

“He’s associated with what we can safely say are pretty value-destructive acquisitions,” said Eleanor Taylor-Jolidon, who manages about 400 million Swiss francs at Union Bancaire Privee in Geneva, including Novartis shares. “Everybody’s hoping that there’s going to be a restructuring now. I hope there will be a restructuring.” . . .

. . .“The shares certainly reacted to the news,” Markus Manns, who manages a health-care fund that includes Novartis shares at Union Investment in Frankfurt, said in an interview. “People are hoping Novartis will sell the Roche stake or the vaccines unit and use the money for a share buyback.”

Oh yes indeed, that's what we're all hoping for, isn't it? A nice big share buyback? And a huge restructuring, one that will stir the pot from bottom to top and make everyone wonder if they'll have a job or where it might be? Speed the day!

No, don't. All this illustrates the different world views that people bring to this business. The investors are looking to maximize their returns - as they should - but those of us in research see the route to maximum returns as going through the labs. That's what you'd expect from us, of course, but are we wrong? A drug company is supposed to find and develop drugs, and how else are you to do that? The investment community might answer that differently: a public drug company, they'd say, is like any other public company. It is supposed to produce value for its shareholders. If it can do that by producing drugs, then great, everything's going according to plan - but if there are other more reliable ways to produce that value, then the company should (must, in fact) avail itself of them.

And there's the rub. Most methods of making a profit are more reliable than drug discovery. Our returns on invested capital for internal projects are worrisome. Even when things work, it's a very jumpy, jerky business, full of fits and starts, with everything new immediately turning into a ticking bomb of a wasting asset due to patent expiry. Some investors understand this and are willing to put up with it in the hopes of getting in on something big. Other investors just want the returns to be smoother and more predictable, and are impatient for the companies to do something to make that happen. And others just avoid us entirely.

Comments (18) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

January 23, 2013

Eating A Whole Bunch of Random Compounds

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Posted by Derek

Reader Andy Breuninger, from completely outside the biopharma business, sends along what I think is an interesting question, and one that bears on a number of issues:

A question has been bugging me that I hope you might answer.

My understanding is that a lot of your work comes down to taking a seed molecule and exploring a range of derived molecules using various metrics and tests to estimate how likely they are to be useful drugs.

My question is this: if you took a normal seed molecule and a standard set of modifications, generated a set of derived molecules at random, and ate a reasonable dose of each, what would happen? Would 99% be horribly toxic? Would 99% have no effect? Would their effects be roughly the same or would one give you the hives, another nausea, and a third make your big toe hurt?

His impression of drug discovery is pretty accurate. It very often is just that: taking one or more lead compounds and running variations on them, trying to optimize potency, specificity, blood levels/absorption/clearance, toxicology, and so on. So, what do most of these compounds do in vivo?

My first thought is "Depends on where you start". There are several issues: (1) We tend to have a defined target in mind when we pick a lead compound, or (if it's a phenotypic assay that got us there), we have a defined activity that we've already seen. So things are biased right from the start; we're already looking at a higher chance of biological activity than you'd have by randomly picking something out of a catalog or drawing something on a board.

And the sort of target can make a big difference. There are an awful lot of kinase enzymes, for example, and compounds tend to cross-react with them, at least in the nearby families, unless you take a lot of care to keep that from happening. Compounds for the G-protein coupled biogenic amines receptors tend to do that, too. On the other hand, you have enzymes like the cytochromes and binding sites like the aryl hydrocarbon receptor - these things are evolved to recognize all sorts of structually disparate stuff. So against the right (or wrong!) sort of targets, you could expect to see a wide range of potential side activities, even before hitting the random ones.

(2) Some structural classes have a lot more biological activity than others. A lot of small-molecule drugs, for example, have some sort of basic amine in them. That's an important recognition element for naturally occurring substances, and we've found similar patterns in our own compounds. So something without nitrogens at all, I'd say, has a lower chance of being active in a living organism. (Barry Sharpless seems to agree with this). That's not to say that there aren't plenty of CHO compounds that can do you harm, just that there are proportionally more CHON ones that can.

Past that rough distinction, there are pharmacophores that tend to hit a lot, sometimes to the point that they're better avoided. Others are just the starting points for a lot of interesting and active compounds - piperazines and imidazoles are two cores that come to mind. I'd be willing to bet that a thousand random piperazines would hit more things than a thousand random morpholines (other things being roughly equal, like molecular weight and polarity), and either of them would hit a lot more than a thousand random cyclohexanes.

(3) Properties can make a big difference. The Lipinski Rule-of-Five criteria come in for a lot of bashing around here, but if I were forced to eat a thousand random compounds that fit those cutoffs, versus having the option to eat a thousand random ones that didn't, I sure know which ones I'd dig my spoon into.

And finally, (4): the dose makes the poison. If you go up enough in dose, it's safe to say that you're going to see an in vivo response to almost anything, including plenty of stuff at the supermarket. Similarly, I could almost certainly eat a microgram of any compound we have in our company's files with no ill effect, although I am not motivated to put that idea to the test. Same goes for the time that you're exposed. A lot of compounds are tolerated for single-dose tox but fail at two weeks. Compounds that make it through two weeks don't always make it to six months, and so on.

How closely you look makes the poison, too. We find that out all the time when we do animal studies - a compound that seems to cause no overt effects might be seen, on necropsy, to have affected some internal organs. And one that doesn't seem to have any visible signs on the tissues can still show effects in a full histopathology workup. The same goes for blood work and other analyses; the more you look, the more you'll see. If you get down to gene-chip analysis, looking at expression levels of thousands of proteins, then you'd find that most things at the supermarket would light up. Broccoli, horseradish, grapefruit, garlic and any number of other things would kick a full expression-profiling assay all over the place.

So, back to the question at hand. My thinking is that if you took a typical lead compound and dosed it at a reasonable level, along with a large set of analogs, then you'd probably find that if any of them had overt effects, they would probably have a similar profile (for good or bad) to whatever the most active compound was, just less of it. The others wouldn't be as potent at the target, or wouldn't reach the same blood levels. The chances of finding some noticeable but completely different activity would be lower, but very definitely non-zero, and would be wildly variable depending on the compound class. These effects might well cluster into the usual sorts of reactions that the body has to foreign substances - nausea, dizziness, headache, and the like. Overall, odds are that most of the compounds wouldn't show much, not being potent enough at any given target, or getting high enough blood levels to show something, but that's also highly variable. And if you looked closely enough, you'd probably find that that all did something, at some level.

Just in my own experience, I've seen one compound out of a series of dopamine receptor ligands suddenly turn up as a vasodilator, noticeable because of the "Rudolph the Red-Nosed Rodent" effect (red ears and tail, too). I've also seen compound series where they started crossing the blood-brain barrier more more effectively at some point, which led to a sharp demarcation in the tolerability studies. And I've seen many cases, when we've started looking at broader counterscreens, where the change of one particular functional group completely knocked a compound out of (or into) activity in some side assay. So you can never be sure. . .

Comments (22) + TrackBacks (0) | Category: Drug Assays | Drug Development | Pharma 101 | Pharmacokinetics | Toxicology

January 22, 2013

The Theology of Ligand Efficiency

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Posted by Derek

So in my post the other day about halogen bonds, I mentioned my unease at sticking in things like bromine and iodine atoms, because of the molecular weight penalty involved. Now, it's only a penalty if you're thinking in terms of ligand efficiency - potency per size of the molecule. I think that it's a very useful concept - one that was unheard of when I started in the industry, but which has now made a wide impression. The idea is that you should try, as much as possible, to make every part of your molecule worth something. Don't hang a chain off unless you're getting binding energy for it, and don't hang a big group off unless you're getting enough binding energy to make it worthwhile.

But how does one measure "worthwhile", or measure ligand efficiency in general? There are several schools of thought. One uses potency divided by molecular weight - there are different ways to make this come out to some sort of standard number, but that's the key operation. Another way, though, is to use potency divided by number of heavy atoms. These two scales will give you answers that are quite close to each other if you're just working in the upper reaches of the periodic table - there's not much difference between carbon, nitrogen, and oxygen. Sulfur will start throwing things off, as will chlorine But where the scales really give totally different answers, at least in common med-chem practice, is with bromine and iodine atoms. A single bromine (edit: fixed from earlier "iodine") weighs as much as a benzene ring, so the molecular-weight-based calculation takes a torpedo, while the heavy atom count just registers one more of the things.

For that very reason, I've been in the molecular-weight camp. But TeddyZ of Practical Fragments showed up in the comments to the halogen bond post, recommending arguments for the other side. But now that I've checked those out, I'm afraid that I still don't find them very convincing.

That's because the post he's referring to makes the case against simple molecular weight cutoffs alone. I'm fine with that. There's no way that you can slice things up by a few mass units here and there in any meaningful way. But the issue here isn't just molecular weight, it's activity divided by weight, and in all the cases shown, the ligand efficiency for the targets of these compounds would have gone to pieces if the "smaller" analog were picked. From a ligand efficiency standpoint, these examples are straw men.

So I still worry about bromine and iodine. I think that they hurt a compound's properties, and that treating them as "one heavy atom", as if they were nitrogens, ignores that. Now, that halogen bond business can, in some cases, make up for that, but medicinal chemists should realize the tradeoffs they're making, in this case as in all the others. I wouldn't, for example, rule out an iodo compound as a drug candidate, just because it's an iodo compound. But that iodine had better be earning its keep (and probably would be doing so via a halogen bond). It has a lot to earn back, too, considering the possible effects on PK and compound stability. Those would be the first things I would check in detail if my iodo candidate led the list in the other factors, like potency and selectivity. Then I'd get it into tox as soon as possible - I have no feel whatsoever for how iodine-substituted compounds act in whole-animal tox studies, and I'd want to find out in short order. That, in fact, is my reaction to unusual structures of many kinds. Don't rule them out a priori; but get to the posteriori part, where you have data, as quickly as possible.

So, thoughts on heavy atoms? Are there other arguments to make in favor of ligand efficiency calculated that way, or do most people use molecule weight?

Comments (26) + TrackBacks (0) | Category: Drug Assays | Drug Development

January 21, 2013

That Many Compounds in Development? Really?

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Posted by Derek

So PhRMA has a press release out on the state of drug research, but it's a little hard to believe. This part, especially:

The report, developed by the Analysis Group and supported by PhRMA, reveals that more than 5,000 new medicines are in the pipeline globally. Of these medicines in various phases of clinical development, 70 percent are potential first-in-class medicines, which could provide exciting new approaches to treating disease for patients.

This set off discussion on Twitter and elsewhere about how these number could have been arrived at. Here's the report itself (PDF), and looking through it provides a few more details Using figures that show up in the body of the report, that looks like between 2164 compounds in Phase I, 2329 in Phase II, and 833 in Phase III. Of those, by far the greatest number are in oncology, where they have 1265, 1507, and 288 in Phase I, II, and III, respectively. Second is infectious disease (304/289/135), and third is neurology (256/273/74). It's worth noting that "Psychiatry" is a separate category all its own, by the way.

An accompanying report (PDF) gives a few more specific figures. It claims, among other things, 66 medicines currently in clinical trials for Hepatitis C, 61 projects for ALS, and 158 for ovarian cancer. Now, it's good to have the exact numbers broken down. But don't those seem rather high?

Here's the section on how these counts were obtained:

Except where otherwise noted, data were obtained from EvaluatePharma, a proprietary commercial database with coverage of over 4,500 companies and approximately 50,000 marketed and pipeline products (including those on-market, discontinued, and in development), and containing historical data from 1986 onward. Pipeline information is available for each stage of development, defined as: Research Project, Preclinical, Phase I, II, III, Filed, and Approved. EvaluatePharma collects and curates information from publicly available sources and contains drug-related information such as company sponsor and therapy area. The data were downloaded on December 12, 2011.

While our interest is in drugs in development that have the potential to become new treatment options for U.S. patients, it is difficult to identify ex ante which drugs in development may eventually be submitted for FDA approval – development activity is inherently global, although regulatory review, launch, and marketing are market-specific. Because most drugs are intended for marketing in the U.S., the largest drug market in the world, we have not excluded any drugs in clinical development (i.e., in Phases I, II, or III). However, in any counts of drugs currently in regulatory review, we have excluded drugs that were not filed with the FDA.

Unless otherwise noted, the analysis in this report is restricted to new drug applications for medicines that would be reviewed as new molecular entities (NMEs) and to new indications for already approved NMEs. . .

Products are defined as having a unique generic name, such that a single product is counted exactly once (regardless of the number of indications being pursued).

That gives some openings for the higher-than-expected numbers. For one, those databases of company activities always seem to run on the high side, because many companies keep things listed as development compounds when they're really ceased any work on them (or in extreme cases, never even really started work at all). Second, there may be some oddities from other countries in there, where the standards for press releases are even lower. But we can rule out a third possibility, that single compounds are being counted across multiple indications. I think that the first-in-class figures are surely pumped up by the cases where there are several compounds all in development for the same (as yet unrealized) target, though. Finally, I think that there's some shuffling between "compounds" and "projects" taking place, with the latter having even larger figures.

I'm going to see in another post if I can break down any of these numbers further - who know, maybe there are a lot more compounds in development than I think. But my first impression is that these numbers are much higher than I would have guessed. It would be very helpful if someone at PhRMA would release a list of the compounds they've counted from one of these indications, just to give us an idea. Any chance of that?

Comments (21) + TrackBacks (0) | Category: Clinical Trials | Drug Development

January 16, 2013

Drug Discovery With the Most Common Words

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Posted by Derek

I got caught up this morning in a challenge based on this XKCD strip, the famous "Up-Goer Five". If that doesn't ring a bell, have a look - it's an attempt to describe a Saturn V rocket while using only the most common 1000 words in English. You find, when you do that, that some of the words you really want to be able to use are not on the list - in the case of the Saturn V, "rocket" is probably the first obstacle of that sort you run into, thus "Up-Goer".

So I noticed on Twitter that people are trying to describe their own work using the same vocabulary list, and I thought I'd give it a try. (Here's a handy text editor that will tell you when you've stepped off the path). I quickly found that "lab", "chemical", "test", and "medicine" are not on the list, so there was enough of a challenge to keep me entertained. Here, then, is drug discovery and development, using the simple word list:

I find things that people take to get better when they are sick. These are hard to make, and take a lot of time and money. When we have a new idea, most of them don't actually work, because we don't know everything we need to about how people get sick in the first place. It's like trying to fix something huge, in the dark, without a book to help.

So we have to try over and over, and we often get surprised by what happens. We build our new stuff by making its parts bigger or smaller, or we join a new piece to one end, or we change one part out for another to see if it works better. Some of our new things are not strong enough. Others break down too fast or stay in the body too long, and some would do too many other things to the people who take them (and maybe even make them more sick than they were). To try to fix all of these at the same time is not easy, of course. When we think we've found one, it has to get past all of those problems, and then we have to be able to make a lot of it exactly the same way every time so that we can go to the next part.

And that part is where most of the money and time come in. First, we try our best idea out on a small animal to make sure that it works like we think it will. Only after that we can ask people to take it. First people who are not sick try it, just to make sure, then a few sick ones, then a lot of sick ones of many types. Then, if it still works, we take all our numbers and ask if it is all right to let everyone who is sick buy our new stuff, and to let a doctor tell them to take it.

If they say yes, we have to do well with it as fast as we can, which doesn't always work out, either. That's because there can still be a problem even after all that work. Even if there isn't, after some time (more than a year or two) someone else can let these people buy it, too, and for less. While all that is going on, we are back trying to find another new one before this one runs out, and we had better.

Not everyone likes us. Our stuff can be a lot of money for people. It may not work as well as someone wants it to, or they may not like how we talk with their doctor (and they may have a point there). Even so, many people have no idea of what we do, how hard it is, or how long it can take. But no one has got any other way to do it, at least not yet!

There, that's fairly accurate, and it even manages to sound like me in some parts. Pity there's no Latin on the list, though.

Update: here are some more people describing their work, in the comments over at Just Like Cooking. And I should note that someone has already remarked to me that "This is an explanation that even Marcia Angell could understand".

Comments (32) + TrackBacks (0) | Category: Drug Development

December 18, 2012

Lilly's Two-Drugs-a-Year Prediction

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Posted by Derek

Drug research consultant Bernard Munos popped in the comments here the other day and mentioned this story from 2010 in the Indiana Business Journal. That's where we can find Eli Lilly's prediction that they were going to start producing two new drugs per year, starting in 2013. Since that year is nearly upon us, how's that looking?

Not too well. Back in 2010, Lilly's CEO (John Lechleiter) was talking up the company's plans to weather its big patent expirations, including that two-a-year forecast. Since then, the company has had a brutal string of late-stage clinical failures. In addition to the ones in that article, Lilly's had to withdraw Xigris, and results for edivoxetine are mixed. No wonder we're hearing so much about the not-too-impressive Alzheimer's drugs from them.

But, as I said here, what would I have done differently, were I to have had to misfortune of having to run Eli Lilly? I might not have placed such a big bet on Alzheimer's, but I probably would have found equally unprofitable ways to spend the money. (And in the end, the company deserves credit for taking on such an intractable disease - just no one tell Marcia Angell; she doesn't think anyone in the drug industry does any such thing).

About the only thing I'm sure of is that I wouldn't have gone around telling people that we were going to start launching two drugs a year. No one's ever been able to keep to that pace, not even in the best of times, and these sure aren't the best of times. It's tempting to think about telling the investors and the analysts that we're going to work as hard as we can, using our brains as much as we can, and we're going to launch what we're going to launch, when it's darn well ready to be launched. And past that, no predictions, OK? The only problem is, the stock market wouldn't stand for it. Ken Frazier at Merck tried something a bit like this, and it sure didn't seem to last long. Is happy talk what everyone would rather hear?

Comments (14) + TrackBacks (0) | Category: Business and Markets | Drug Development

December 3, 2012

Marcia Angell's Interview: I Just Can't

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Posted by Derek

I have tried to listen to this podcast with Marcia Angell, on drug companies and their research, but I cannot seem to make it all the way through. I start shouting at the screen, at the speakers, at the air itself. In case you're wondering about whether I'm overreacting, at one point she makes the claim that drug companies don't do much innovation, because most of our R&D budget is spent on clinical trials, and "everyone knows how to do a clinical trial". See what I mean?

Angell has many very strongly held opinions on the drug business. But her take on R&D has always seemed profoundly misguided to me. From what I can see, she thinks that identifying a drug target is the key step, and that everything after that is fairly easy, fairly cheap, and very, very profitable. This is not correct. Really, really, not correct. She (and those who share this worldview, such as her co-author) believe that innovation has fallen off in the industry, but that this has happened mostly by choice. Considering the various disastrously expensive failures the industry has gone through while trying to expand into new diseases, new indications, and new targets, I find this line of argument hard to take.

So, I see, does Alex Tabarrok. I very much enjoyed that post; it does some of the objecting for me, and illustrates why I have such a hard time dealing point-by-point with Angell and her ilk. The misconceptions are large, various, and ever-shifting. Her ideas about drug marketing costs, which Tabarrok especially singles out, are a perfect example (and see some of those other links to my old posts, where I make some similar arguments to his).

So no, I don't think that Angell has changed her opinions much. I sure haven't changed mine.

Comments (60) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Drug Prices | Why Everyone Loves Us

November 30, 2012

A Broadside Against The Way We Do Things Now

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Posted by Derek

There's a paper out in Drug Discovery Today with the title "Is Poor Research the Cause of Declining Productivity in the Drug Industry? After reviewing the literature on phenotypic versus target-based drug discovery, the author (Frank Sams-Dodd) asks (and has asked before):

The consensus of these studies is that drug discovery based on the target-based approach is less likely to result in an approved drug compared to projects based on the physiological- based approach. However, from a theoretical and scientific perspective, the target-based approach appears sound, so why is it not more successful?

He makes the points that the target-based approach has the advantages of (1) seeming more rational and scientific to its practitioners, especially in light of the advances in molecular biology over the last 25 years, and (2) seeming more rational and scientific to the investors:

". . .it presents drug discovery as a rational, systematic process, where the researcher is in charge and where it is possible to screen thousands of compounds every week. It gives the image of industrialisation of applied medical research. By contrast, the physiology-based approach is based on the screening of compounds in often rather complex systems with a low throughput and without a specific theory on how the drugs should act. In a commercial enterprise with investors and share-holders demanding a fast return on investment it is natural that the drug discovery efforts will drift towards the target-based approach, because it is so much easier to explain the process to others and because it is possible to make nice diagrams of the large numbers of compounds being screened.

This is the "Brute Force bias". And he goes on to another key observation: that this industrialization (or apparent industrialization) meant that there were a number of processes that could be (in theory) optimized. Anyone who's been close to a business degree knows how dear process optimization is to the heart of many management theorists, consultants, and so on. And there's something to that, if you're talking about a defined process like, say, assembling pickup trucks or packaging cat litter. This is where your six-sigma folks come in, your Pareto analysis, your Continuous Improvement people, and all the others. All these things are predicated on the idea that there is a Process out there.

See if this might sound familiar to anyone:

". . .the drug dis- covery paradigm used by the pharmaceutical industry changed from a disease-focus to a process-focus, that is, the implementation and organisation of the drug discovery process. This meant that process-arguments became very important, often to the point where they had priority over scientific considerations, and in many companies it became a requirement that projects could conform to this process to be accepted. Therefore, what started as a very sensible approach to drug discovery ended up becoming the requirement that all drug dis- covery programmes had to conform to this approach – independently of whether or not sufficient information was available to select a good target. This led to dogmatic approaches to drug discovery and a culture developed, where new projects must be presented in a certain manner, that is, the target, mode-of-action, tar- get-validation and screening cascade, and where the clinical manifestation of the disease and the biological basis of the disease at systems-level, that is, the entire organism, were deliberately left out of the process, because of its complexity and variability.

But are we asking too much when we declare that our drugs need to work through single defined targets? Beyond that, are we even asking too much when we declare that we need to understand the details of how they work at all? Many of you will have had such thoughts (and they've been expressed around here as well), but they can tend to sound heretical, especially that second one. But that gets to the real issue, the uncomfortable, foot-shuffling, rather-think-about-something-else question: are we trying to understand things, or are we trying to find drugs?

"False dichotomy!", I can hear people shouting. "We're trying to do both! Understanding how things work is the best way to find drugs!" In the abstract, I agree. But given the amount there is to understand, I think we need to be open to pushing ahead with things that look valuable, even if we're not sure why they do what they do. There were, after all, plenty of drugs discovered in just that fashion. A relentless target-based environment, though, keeps you from finding these things at all.

What it does do, though, is provide vast opportunities for keeping everyone busy. And not just "busy" in the sense of working on trivia, either: working out biological mechanisms is very, very hard, and in no area (despite decades of beavering away) can we say we've reached the end and achieved anything like a complete picture. There are plenty of areas that can and will soak up all the time and effort you can throw at them, and yield precious little in the way of drugs at the end of it. But everyone was working hard, doing good science, and doing what looked like the right thing.

This new paper spends quite a bit of time on the mode-of-action question. It makes the point that understanding the MoA is something that we've imposed on drug discovery, not an intrinsic part of it. I've gotten some funny looks over the years when I've told people that there is no FDA requirement for details of a drug's mechanism. I'm sure it helps, but in the end, it's efficacy and safety that carry the day, and both of those are determined empirically: did the people in the clinical trials get better, or worse?

And as for those times when we do have mode-of-action information, well, here are some fighting words for you:

". . .the ‘evidence’ usually involves schematic drawings and flow-diagrams of receptor complexes involving the target. How- ever, it is almost never understood how changes at the receptor or cellular level affect the phy- siology of the organism or interfere with the actual disease process. Also, interactions between components at the receptor level are known to be exceedingly complex, but a simple set of diagrams and arrows are often accepted as validation for the target and its role in disease treatment even though the true interactions are never understood. What this in real life boils down to is that we for almost all drug discovery programmes only have minimal insight into the mode-of-action of a drug and the biological basis of a disease, meaning that our choices are essentially pure guess-work.

I might add at this point that the emphasis on defined targets and mode of action has been so much a part of drug discovery in recent times that it's convinced many outside observers that target ID is really all there is to it. Finding and defining the molecular target is seen as the key step in the whole process; everything past that is just some minor engineering (and marketing, naturally). That fact that this point of view is a load of fertilizer has not slowed it down much.

I think that if one were to extract a key section from this whole paper, though, this one would be a good candidate:

". . .it is not the target-based approach itself that is flawed, but that the focus has shifted from disease to process. This has given the target-based approach a dogmatic status such that the steps of the validation process are often conducted in a highly ritualised manner without proper scientific analysis and questioning whether the target-based approach is optimal for the project in question.

That's one of those "Don't take this in the wrong way, but. . ." statements, which are, naturally, always going to be taken in just that wrong way. But how many people can deny that there's something to it? Almost no one denies that there's something not quite right, with plenty of room for improvement.

What Sams-Dodd has in mind for improvement is a shift towards looking at diseases, rather than targets or mechanisms. For many people, that's going to be one of those "Speak English, man!" moments, because for them, finding targets is looking at diseases. But that's not necessarily so. We would have to turn some things on their heads a bit, though:

In recent years there have been considerable advances in the use of automated processes for cell-culture work, automated imaging systems for in vivo models and complex cellular systems, among others, and these developments are making it increasingly possible to combine the process-strengths of the target-based approach with the disease-focus of the physiology-based approach, but again these technologies must be adapted to the research question, not the other way around.

One big question is whether the investors funding our work will put up with such a change, or with such an environment even if we did establish it. And that gets back to the discussion of Andrew Lo's securitization idea, the talk around here about private versus public financing, and many other topics. Those I'll reserve for another post. . .

Comments (30) + TrackBacks (0) | Category: Drug Assays | Drug Development | Drug Industry History | Who Discovers and Why

November 29, 2012

When Drug Launches Go Bad

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Posted by Derek

For those connoisseurs of things that have gone wrong, here's a list of the worst drug launches of recent years. And there are some rough ones in there, such as Benlysta, Provenge, and (of course) Makena. And from an aesthetic standpoint, it's hard not to think that if you name your drug Krystexxa that you deserve what you get. Read up and try to avoid being part of such a list yourself. . .

Comments (8) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Drug Prices

Roche Repurposes

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Posted by Derek

Another drug repurposing initiative is underway, this one between Roche and the Broad Institute. The company is providing 300 failed clinical candidates to be run through new assays, in the hopes of finding a use for them.

I hope something falls out of this, because any such compounds will naturally have a substantial edge in further development. They should all have been through toxicity testing, they've had some formulations work done on them, a decent scale-up route has been identified, and so on. And many of these candidates fell out in Phase II, so they've even been in human pharmacokinetics.

On the other hand (there's always another hand), you could also say that this is just another set of 300 plausible-looking compounds, and what does a 300-compound screening set get you? The counterargument to this is that these structures have not only been shown to have good absorption and distribution properties (no small thing!), they've also been shown to bind well to at least one target, which means that they may well be capable of binding well to other similar motifs in other active sites. But the counterargument to that is that now you've removed some of those advantages in the paragraph above, because any hits will now come with selectivity worries, since they come with guaranteed activity against something else.

This means that the best case for any repurposed compound is for its original target to be good for something unanticipated. So that Roche collection of compounds might also be thought of as a collection of failed targets, although I doubt if there are a full 300 of those in there. Short of that, every repurposing attempt is going to come with its own issues. It's not that I think these shouldn't be tried - why not, as long as it doesn't cost too much - but things could quickly get more complicated than they might have seemed. And that's a feeling that any drug discovery researcher will recognize like an old, er, friend.

For more on the trickiness of drug repurposing, see John LaMattina here and here. And the points he raises get to the "as long as it doesn't cost too much" line in the last paragraph. There's opportunity cost involved here, too, of course. When the Broad Institute (or Stanford, or the NIH) screens old pharma candidates for new uses, they're doing what a drug company might do itself, and therefore possibly taking away from work that only they could be doing instead. Now, I think that the Broad (for example) already has a large panel of interesting screens set up, so running the Roche compounds through them couldn't hurt, and might not take that much more time or effort. So why not? But trying to push repurposing too far could end up giving us the worst of both worlds. . .

Comments (14) + TrackBacks (0) | Category: Drug Assays | Drug Development | Drug Industry History

November 28, 2012

Every Tiny Detail

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Posted by Derek

Via Chemjobber, we have here an excellent example of how much detail you have to get into if you're seriously making a drug for the market. When you have to account for every impurity, and come up with procedures that generate the same ones within the same tight limits every time, this is the sort of thing you have to pay attention to: how you dry your compound. And how long. And why. Because if you don't, huge amounts of money (time, lost revenue, regulatory trouble, lawsuits) are waiting. . .

Comments (5) + TrackBacks (0) | Category: Analytical Chemistry | Chemical News | Drug Development

November 19, 2012

The Novartis Pipeline

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Posted by Derek

This would seem to be inviting the wrath of the Drug Development Gods, and man, are they a testy bunch: "Novartis could produce 14 or more new big-selling 'blockbuster' drugs within five years . . ."

I'll certainly wish them luck on that, and it certainly seems true that Novartis research has been productive. But think back - how many press releases have you seen over the years where Drug Company A predicts X number of big product launches in the next Y years? And how many of those schedules have ever quite worked out? The most egregious examples of this take the form of claiming that your new strategy/platform/native genius/good looks have now allowed you to deliver these things on some sort of regular schedule. When you hear someone talking about how even though they haven't been able to do anything like it in the past, they're going to start unleashing a great new drug product launch every year (or every 18 months, what have you) from here on out, run.

Now, Novartis isn't talking like this, and they have a much better chance of delivering on this than most, but still. Might it not be better just to creep up on people with all those great new products in hand, rather than risk disappointment?

Comments (10) + TrackBacks (0) | Category: Business and Markets | Drug Development

November 13, 2012

Nassim Taleb on Scientific Discovery

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Posted by Derek

There's an interesting article posted on Nassim Taleb's web site, titled "Understanding is a Poor Substitute for Convexity (Antifragility)". It was recommended to me by a friend, and I've been reading it over for its thoughts on how we do drug research. (This would appear to be an excerpt from, or summary of, some of the arguments in the new book Antifragile: Things That Gain from Disorder, which is coming out later this month).

Taleb, of course, is the author of The Black Swan and Fooled by Randomness, which (along with his opinions about the recent financial crises) have made him quite famous.

So this latest article is certainly worth reading, although much of it reads like the title, that is, written in fluent and magisterial Talebian. This blog post is being written partly for my own benefit, so that I make sure to go to the trouble of a translation into my own language and style. I've got my idiosyncracies, for sure, but I can at least understand my own stuff. (And, to be honest, a number of my blog posts are written in that spirit, of explaining things to myself in the process of explaining them to others).

Taleb starts off by comparing two different narratives of scientific discovery: luck versus planning. Any number of works contrast those two. I'd say that the classic examples of each (although Taleb doesn't reference them in this way) are the discovery of penicillin and the Manhattan Project. Not that I agree with either of those categorizations - Alexander Fleming, as it turns out, was an excellent microbiologist, very skilled and observant, and he always checked old culture dishes before throwing them out just to see what might turn up. And, it has to be added, he knew what something interesting might look like when he saw it, a clear example of Pasteur's quote about fortune and the prepared mind. On the other hand, the Manhattan Project was a tremendous feat of applied engineering, rather than scientific discovery per se. The moon landings, often used as a similar example, are also the exact sort of thing. The underlying principles of nuclear fission had been worked out; the question was how to purify uranium isotopes to the degree needed, and then how to bring a mass of the stuff together quickly and cleanly enough. These processes needed a tremendous amount of work (it wasn't obvious how to do either one, and multiple approaches were tried under pressure of time), but the laws of (say) gaseous diffusion were already known.

But when you look over the history of science, you see many more examples of fortunate discoveries than you see of planned ones. Here's Taleb:

The luck versus knowledge story is as follows. Ironically, we have vastly more evidence for results linked to luck than to those coming from the teleological, outside physics —even after discounting for the sensationalism. In some opaque and nonlinear fields, like medicine or engineering, the teleological exceptions are in the minority, such as a small number of designer drugs. This makes us live in the contradiction that we largely got here to where we are thanks to undirected chance, but we build research programs going forward based on direction and narratives. And, what is worse, we are fully conscious of the inconsistency.

"Opaque and nonlinear" just about sums up a lot of drug discovery and development, let me tell you. But Taleb goes on to say that "trial and error" is a misleading phrase, because it tends to make the two sound equivalent. What's needed is an asymmetry: the errors need to be as painless as possible, compared to the payoffs of the successes. The mathematical equivalent of this property is called convexity; a nonlinear convex function is one with larger gains than losses. (If they're equal, the function is linear). In research, this is what allows us to "harvest randomness", as the article puts it.

An example of such a process is biological evolution: most mutations are harmless and silent. Even the harmful ones will generally just kill off the one organism with the misfortune to bear them. But a successful mutation, one that enhances survival and reproduction, can spread widely. The payoff is much larger than the downside, and the mutations themselves come along for free, since some looseness is built into the replication process. It's a perfect situation for blind tinkering to pay off: the winners take over, and the losers disappear.

Taleb goes on to say that "optionality" is another key part of the process. We're under no obligation to follow up on any particular experiment; we can pick the one that worked best and toss the rest. This has its own complications, since we have our own biases and errors of judgment to contend with, as opposed to the straightforward questions of evolution ("Did you survive? Did you breed?"). But overall, it's an important advantage.

The article then introduces the "convexity bias", which is defined as the difference between a system with equal benefit and harm for trial and error (linear) and one where the upsides are higher (nonlinear). The greater the split between those two, the greater the convexity bias, and the more volatile the environment, the great the bias is as well. This is where Taleb introduces another term, "antifragile", for phenomena that have this convexity bias, because they're equipped to actually gain from disorder and volatility. (His background in financial options is apparent here). What I think of at this point is Maxwell's demon, extracting useful work from randomness by making decisions about which molecules to let through his gate. We scientists are, in this way of thinking, members of the same trade union as Maxwell's busy creature, since we're watching the chaos of experimental trials and natural phenomena and letting pass the results we find useful. (I think Taleb would enjoy that analogy). The demon is, in fact, optionality manifested and running around on two tiny legs.

Meanwhile, a more teleological (that is, aimed and coherent) approach is damaged under these same conditions. Uncertainty and randomness mess up the timelines and complicate the decision trees, and it just gets worse and worse as things go on. It is, by these terms, fragile.

Taleb ends up with seven rules that he suggests can guide decision making under these conditions. I'll add my own comments to these in the context of drug research.

(1) Under some conditions, you'd do better to improve the payoff ratio than to try to increase your knowledge about what you're looking for. One way to do that is to lower the cost-per-experiment, so that a relatively fixed payoff then is larger in comparison. The drug industry has realized this, naturally: our payoffs are (in most cases) somewhat out of our control, although the marketing department tries as hard as possible. But our costs per experiment range from "not cheap" to "potentially catastrophic" as you go from early research to Phase III. Everyone's been trying to bring down the costs of later-stage R&D for just these reasons.

(2) A corollary is that you're better off with as many trials as possible. Research payoffs, as Taleb points out, are very nonlinear indeed, with occasional huge winners accounting for a disproportionate share of the pool. If we can't predict these - and we can't - we need to make our nets as wide as possible. This one, too, is appreciated in the drug business, but it's a constant struggle on some scales. In the wide view, this is why the startup culture here in the US is so important, because it means that a wider variety of ideas are being tried out. And it's also, in my view, why so much M&A activity has been harmful to the intellectual ecosystem of our business - different approaches have been swallowed up, and they they disappear as companies decide, internally, on the winners.

And inside an individual company, portfolio management of this kind is appreciated, but there's a limit to how many projects you can keep going. Spread yourself too thin, and nothing will really have a chance of working. Staying close to that line - enough projects to pick up something, but not so many as to starve them all - is a full-time job.

(3) You need to keep your "optionality" as strong as possible over as long a time as possible - that is, you need to be able to hit a reset button and try something else. Taleb says that plans ". . .need to stay flexible with frequent ways out, and counter to intuition, be very short term, in order to properly capture the long term. Mathematically, five sequential one-year options are vastly more valuable than a single five-year option." I might add, though, that they're usually priced accordingly (and as Taleb himself well knows, looking for those moments when they're not priced quite correctly is another full-time job).

(4) This one is called "Nonnarrative Research", which means the practice of investing with people who have a history of being able to do this sort of thing, regardless of their specific plans. And "this sort of thing" generally means a lot of that third recommendation above, being able to switch plans quickly and opportunistically. The history of many startup companies will show that their eventual success often didn't bear as much relation to their initial business plan as you might think, which means that "sticking to a plan", as a standalone virtue, is overrated.

At any rate, the recommendation here is not to buy into the story just because it's a good story. I might draw the connection here with target-based drug discovery, which is all about good stories.

(5) Theory comes out of practice, rather than practice coming out of theory. Ex post facto histories, Taleb says, often work the story around to something that looks more sensible, but his claim is that in many fields, "tinkering" has led to more breakthroughs than attempts to lay down new theory. His reference is to this book, which I haven't read, but is now on my list.

(6) There's no built-in payoff for complexity (or for making things complex). "In academia," though, he says, "there is". Don't, in other words, be afraid of what look like simple technologies or innovations. They may, in fact, be valuable, but have been ignored because of this bias towards the trickier-looking stuff. What this reminds me of is what Philip Larkin said he learned by reading Thomas Hardy: never be afraid of the obvious.

(7) Don't be afraid of negative results, or paying for them. The whole idea of optionality is finding out what doesn't work, and ideally finding that out in great big swaths, so we can narrow down to where the things that actually work might be hiding. Finding new ways to generate negative results quickly and more cheaply, which can means new ways to recognize them earlier, is very valuable indeed.

Taleb finishes off by saying that people have criticized such proposals as the equivalent of buying lottery tickets. But lottery tickets, he notes, are terribly overpriced, because people are willing to overpay for a shot at a big payoff on long odds. But lotteries have a fixed upper bound, whereas R&D's upper bound is completely unknown. And Taleb gets back to his financial-crisis background by pointing out that the history of banking and finance points out the folly of betting against long shots ("What are the odds of this strategy suddenly going wrong?"), and that in this sense, research is a form of reverse banking.

Well, those of you out there who've heard the talk I've been giving in various venues (and in slightly different versions) the last few months may recognize that point, because I have a slide that basically says that drug research is the inverse of Wall Street. In finance, you try to lay off risk, hedge against it, amortize it, and go for the steady payoff strategies that (nonetheless) once in a while blow up spectacularly and terribly. Whereas in drug research, risk is the entire point of our business (a fact that makes some of the business-trained people very uncomfortable). We fail most of the time, but once in a while have a spectacular result in a good direction. Wall Street goes short risk; we have to go long.

I've been meaning to get my talk up on YouTube or the like; and this should force me to finally get that done. Perhaps this weekend, or over the Thanksgiving break, I can put it together. I think it fits in well with what Taleb has to say.

Comments (27) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Who Discovers and Why

October 30, 2012

JQ1: Giving Up a Fortune?

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Posted by Derek

The Atlantic is out with a list of "Brave Thinkers", and one of them is Jay Bradner at Harvard Medical School. He's on there for JQ1, a small-molecule bromodomain ligand that was reported in 2010. (I note, in passing, that once again nomenclature has come to the opposite of our rescue, since bromodomains have absolutely nothing to do with bromine, in contrast to 98% of all the other words that begin with "bromo-")

These sorts of compounds have been very much in the news recently, as part of the whole multiyear surge in epigenetic research. Drug companies, naturally, are looking to the epigenetic targets that might be amenable to small-molecule intervention, and bromodomains seem to qualify (well, some of them do, anyway).

At any rate, JQ1 is a perfectly reasonable probe compound for bromodomain studies, but it got a lot of press a couple of months ago as a potential male contraceptive. I found all that wildly premature - a compound like this one surely sets off all kinds of effects in vivo, and disruption of spermatogenesis is only one of them. Note (PDF) that it hits a variety of bromodomain subtypes, and we only have the foggiest notion of what most of these are doing in real living systems.

The Atlantic, for its part, makes much of Bradner's publishing JQ1 instead of patenting it:

The monopoly on developing the molecule that Bradner walked away from would likely have been worth a fortune (last year, the median value for U.S.-based biotech companies was $370 million). Now four companies are building on his discovery—which delights Bradner, who this year released four new molecules. “For years, drug discovery has been a dark art performed behind closed doors with the shades pulled,” he says. “I would be greatly satisfied if the example of this research contributed to a change in the culture of drug discovery.”

But as Chemjobber rightly says, the idea that Bradner walked away from a fortune is ridiculous. JQ1 is not a drug, nor is it ever likely to become a drug. It has inspired research programs to find drugs, but they likely won't look much (or anything) like JQ1, and they'll do different things (for one, they'll almost surely be more selective). In fact, chasing after that sort of selectivity is one of the things that Bradner's own research group appears to be doing - and quite rightly - while his employer (Dana-Farber) is filing patent applications on JQ1 derivatives. Quite rightly.

Patents work differently in small-molecule drug research than most people seem to think. (You can argue, in fact, that it's one of the areas where the system works most like it was designed to, as opposed to often-abominable patent efforts in software, interface design, business methods, and the like). People who've never had to work with them have ideas about patents being dark, hidden boxes of secrets, but one of the key things about a patent is disclosure. You have to tell people what your invention is, what it's good for, and how to replicate it, or you don't have a valid patent.

Admittedly, there are patent applications that do not make all of these steps easy - a case in point would be the ones from Exelixis - I wrote here about my onetime attempts to figure out the structures of some of their lead compounds from their patent filings. Not long ago I had a chance to speak with someone who was there at the time, and he was happy to hear that I'd come up short, saying that this had been exactly the plan). But at the same time, all their molecules were in there, along with all the details of how to make them. And the claims of the patents detailed exactly why they were interested in such compounds, and what they planned to do with them as drugs. You could learn a lot about what Exelixis was up to; it was just that finding out the exact structure of the clinical candidate that was tricky. A patent application on JQ1 would have actually ended up disclosing most (or all) of what the publication did.

I'm not criticizing Prof. Bradner and his research group here. He's been doing excellent work in this area, and his papers are a pleasure to read. But the idea that Harvard Medical School and Dana-Farber would walk away from a pharma fortune is laughable.

Comments (33) + TrackBacks (0) | Category: Cancer | Chemical Biology | Drug Development | Patents and IP

October 17, 2012

Zafgen's Epoxide Adventure

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Posted by Derek

Zafgen is a startup in the Boston area that's working on a novel weight-loss drug called beloranib. Their initial idea was that they were inhibiting angiogenesis in adipose tissue, through inhibition of methionine aminopeptidase-2. But closer study showed that while the compound was indeed causing significant weight loss in animal models, it wasn't through that mechanism. Blood vessel formation wasn't affected, but the current thinking is that Met-AP2 inhibition is affecting fatty acid synthesis and causing more usage of lipid stores.

But when they say "novel", they do mean it. Behold one of the more unlikely-looking drugs to make it through Phase I:
Beloranib.png
Natural-product experts in the audience might experience a flash of recognition. That's a derivative of fumagillin, a compound from Aspergillus that's been kicking around for many years now. And its structure brings up a larger point about reactive groups in drug molecules, the kind that form covalent bonds with their targets.

I wrote about covalent drugs here a few years ago, and the entire concept has been making a comeback. (If anyone was unsure about that, Celgene's purchase of Avila was the convincer). Those links address the usual pros and cons of the idea: on the plus side, slow off rates are often beneficial in drug mechanisms, and you don't get much slower than covalency. On the minus side, you have to worry about selectivity even more, since you really don't want to go labeling across the living proteome. You have the mechanisms of the off-target proteins to worry about once you shut them down, and you also have the ever-present fear of setting off an immune response if the tagged protein ends up looking sufficiently alien.

I'm not aware of any published mechanistic studies of beloranib, but it is surely another one of this class, with those epoxides. (Looks like it's thought to go after a histidine residue, by analogy to fumagillin's activity against the same enzyme). But here's another thing to take in: epoxides are not as bad as most people think they are. We organic chemists see them and think that they're just vibrating with reactivity, but as electrophiles, they're not as hot as they look.

That's been demonstrated by several papers from the Cravatt labs at Scripps. (He still is at Scripps, right? You need a scorecard these days). In this work, they showed that some simple epoxides, when exposed to entire proteomes, really didn't label many targets at all compared to the other electrophiles on their list. And here, in an earlier paper, they looked at fumagillin-inspired spiroexpoxide probes specifically, and found an inhibitor of phosphoglycerate mutase 1. But a follow-up SAR study of that structure showed that it was very picky indeed - you had to have everything lined up right for the epoxide to react, and very close analogs had no effect. Taken together, the strong implication is that epoxides can be quite selective, and thus can be drugs. You still want to be careful, because the toxicology literature is still rather vocal on the subject, but if you're in the less reactive/more structurally complex/more selective part of that compound space, you might be OK. We'll see if Zafgen is.

Comments (21) + TrackBacks (0) | Category: Chemical Biology | Diabetes and Obesity | Drug Development

October 11, 2012

IGFR Therapies Wipe Out. And They're Not Alone.

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Posted by Derek

Here's a look at something that doesn't make many headlines: the apparent failure of an entire class of potential drugs. The insulin-like growth factor 1 receptor (IGF-1R) has been targeted for years now, from a number of different angles. There have been several antibodies tried against it, and companies have also tried small molecule approaches such as inhibiting the associated receptor kinase. (I was on such a project myself a few years back). So far, nothing has worked out.

And as that review shows, this was a very reasonable-sounding idea. Other growth factor receptors have been successful cancer targets (notably EGFR), and there was evidence of IGFR over-expression in several widespread cancer types (and evidence from mouse models that inhibiting it would have the desired effect). The rationale here was as solid as anything we have, but reality has had other ideas:

It is hardly surprising that even some of the field's pioneers are now pessimistic. “In the case of IGF-1R, one can protest that proper studies have not yet been carried out,” writes Renato Baserga, from the department of Cancer Biology, Thomas Jefferson University in Philadelphia. (J. Cell. Physiol., doi:10.1002/jcp.24217). A pioneer in IGF-1 research, Baserga goes on to list some avenues that may still be promising, such as targeting the receptor to prevent metastases in colorectal cancer patients. But in the end, he surmises: “These excuses are poor excuses, [they are] an attempt to reinvigorate a procedure that has failed.” Saltz agrees. “This may be the end of the story,” he says. “At one point, there were more than ten companies developing these drugs; now this may be the last one that gets put on the shelf.”

But, except for articles like these in journals like Nature Biotechnology, or mentions on web sites like this one, no one really hears about this sort of thing. We've talked about this phenomenon before; there's a substantial list of drug targets that looked very promising, got a lot of attention for years, but never delivered any sort of drug at all. Negative results don't make for much of a headline in the popular press, especially when the story develops over a multi-year period.

I think it would be worthwhile for people to hear about this, though. I once talked with someone who was quite anxious about an upcoming plane trip; they were worried on safety grounds. It occurred to me that if there were a small speaker on this person's desk announcing all the flights that had landed safely around the country (or around the world), that a few days of that might actually have an effect. Hundreds, thousands of announcements, over and over: "Flight XXX has landed safely in Omaha. Flight YYY has landed safely in Seoul. Flight ZZZ has landed safely in Amsterdam. . ." Such a speaker system wouldn't shut up for long suring any given day, that's for sure, and it would emphasize the sheer volume of successful air travel that takes place each day, over and over.

On the other hand, almost all drug research programs, or never even make it off the ground in the first place. In this field, actually getting a plane together, getting it into the air, and guiding it to a landing at the FDA only happens once in a rather long while, which is why there are plenty of people out there in early research who've never worked on anything that's made it to market. A list of all the programs that failed would be instructive, and might get across how difficult finding a drug really is, but no one's going to be able to put one of those together. Companies don't even announce the vast majority of their preclinical failures; they're below everyone else's limit of detection. I can tell you for sure that most of the non-delivering programs I've worked on have never seen daylight of any sort. They just quietly disappeared.

Comments (10) + TrackBacks (0) | Category: Cancer | Drug Development | Drug Industry History

September 24, 2012

The One-Stop CRO

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Posted by Derek

C&E News has a good articlehttp://cen.acs.org/articles/90/i39/One-Stop-Shops-Emerge-Drug.html out on the so-called "one-stop shop" contract research organizations in pharma - these are the Covances and WuXis of the world, who can take on all sorts of preclinical (and clinical) jobs for you under one umbrella.

The old debate over one-stop shopping has, however, become more nuanced in the current pharmaceutical industry environment. Service firms and their customers agree that much of the decision making comes down to where to outsource workhorse chemistry and where to outsource frontline science. Sources agree that a market still exists for boutique CROs that focus on one node along the discovery/development continuum. And some drug firms say they are working with more than one full-service vendor, negating the supposed advantage of one-stop shopping.


There's more of this sort of thing around than ever, of course, but the merits of the whole idea are still being debated. There's no questions that these companies can extend the reach of an organization that doesn't have all these specialities itself, but that doesn't mean that you can't mess things up, either.

Not every drug firm is scaling down internal research. Sonia Pawlak, manager of strategic outsourcing in chemical development at Gilead Sciences, says drug companies with fully developed R&D operations will likely not see much advantage in working with a one-stop-shop contractor. . .Geographical proximity to a supplier is important to Gilead, Pawlak adds, questioning whether linking research and manurfacturing assets across different continents saves the customer time.

I'm used to looking at these companies from the buying end. When you consider the whole CRO world from the other direction, though, you see a vision of de-risked pharma. These people are going to get paid, whether the preclinical program works out or not, whether the clinical trials work or not, whether the eventual drug is approved or not. It's a contract business.

But they're also never going to get paid more than what is in that contract - they will share in no windfalls, get pieces of no blockbusters. So eventually, you end up with two halves of the whole drug R&D business: a drug company that does little or no outsourcing (along with the small R&D discovery companies that outsource everything they can) are in the part that takes the big risks and goes for the big victories, while the CROs are the part that takes on (comparatively) no risk in exchange for a smaller guaranteed payout.

Comments (11) + TrackBacks (0) | Category: Drug Development

September 21, 2012

Transcelerate: What Is It, Exactly?

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Posted by Derek

A list of big pharma companies have announced that they're setting up a joint venture, Trancelerate, to try to address common precompetitive drug development problems. But that covers a broad area, and this collaboration is more narrowly focused:

Members of TransCelerate have identified clinical study execution as the initiative's initial area of focus. Five projects have been selected by the group for funding and development, including: development of a shared user interface for investigator site portals; mutual recognition of study site qualification and training; development of risk-based site monitoring approach and standards; development of clinical data standards; and establishment of a comparator drug supply model.

Now, that paragraph is hard to get through, I have to say. I understand what they're getting at, and these are all worthy objectives, but I think it could be boiled down to saying "We're going to try not to duplicate each other's work so much when we're setting up clinical trials and finding places to run them. They cost so much already that it's silly for us all to spend money doing the same things that have to be done every time." And other than this, details are few. The initiative will be headquartered in Philadelphia, but that seems to be about it so far.

But this it won't get at the fundamental problems in drug research. Our clinical failure rate of around 90% has very little to do with the factors that Transcelerate is addressing - what they're trying to do is make that failure rate less of a financial burden. That's certainly worth taking on, in lieu of figuring out why our drugs crash and burn so often. That one is a much tougher problem, easily proven by the fact that there are billions of dollars waiting to be picked up for even partial solutions to it.

Comments (17) + TrackBacks (0) | Category: Clinical Trials | Drug Development

September 18, 2012

Going After the Big Cyclic Ones

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Posted by Derek

I wrote last year about macrocyclic compounds and their potential as drugs. Now BioCentury has a review of the companies working in this area, and there are more of them than I thought. Ensemble and Aileron are two that come to mind (if you count "stapled peptides" as macrocycles, and I think they should). But there are also Bicycle, Encycle, Lanthio, Oncodesign, Pepscan, PeptiDream, Polyphor, Protagonist, and Transzyme. These companies have a lot of different approaches. Many of them (but not all) are using cyclic peptides, but there are different ways of linking these, different sorts of amino acids you can use in them, and so on. And the non-peptidic approaches have an even wider variety. So I've no doubt that there's room in this area for all these companies - but I also have no doubt that not all these approaches are going to work equally well. And we're just barely getting to the outer fringes of sorting that out:

While much of the excitement over macrocycles is due to their potential to disrupt intracellular protein-protein interactions, every currently disclosed lead program in the space targets an extracellular protein. This reality reflects the challenge of developing a potent and cell-penetrant macrocyclic compound.

Tranzyme and Polyphor are the only companies with macrocyclic compounds in the clinic. Polyphor’s lead compound is POL6326, a conformationally constrained peptide that antagonizes CXC chemokine receptor 4 (CXCR4; NPY3R). It is in Phase II testing to treat multiple myeloma (MM) using autologous transplantation of hematopoietic stem cells.

Tranzyme’s lead compound is TZP-102, an orally administered ghrelin receptor agonist in Phase IIb testing to treat diabetic gastroparesis.

Two weeks ago, Aileron announced it hopes to start clinical development of its lead internally developed program in 2013. The compound, ALRN-5281, targets the growth hormone-releasing hormone (GHRH) receptor.

Early days, then. It's understandable that the first attempts in this area will come via extracellular-acting, iv-administered agents - those are the lowest bars to clear for a new technology. But if this area is going to live up to its potential, it'll have to go much further along than that. We're going to have to learn a lot more about cellular permeability, which is a very large side effect (a "positive externality", as the economists say) of pushing the frontiers back like this: you figure these things out because you have to.

Comments (9) + TrackBacks (0) | Category: Drug Development | Pharmacokinetics

September 10, 2012

Geron, And The Risk of Cancer Therapies

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Posted by Derek

Geron's telomerase inhibitor compound, imetalstat, showed a lot of interesting results in vitro, and has been in Phase II trials all this year. Until now. The company announced this morning that the interim results of their breast-cancer trial are so unpromising that it's been halted, and that lung cancer data aren't looking good, either. The company's stock has been cratering in premarket trading, and this stock analyst will now have some thinking to do, as will the people who followed his advice last week.

I'm sorry to see the first telomerase inhibitor perform so poorly; we need all the mechanisms we can get in oncology. And this is terrible news for Geron, since they'd put all their money down on this therapeutic area. But this is drug discovery; this is research: a lot of good, sensible, promising ideas just don't work.

That phrase comes to mind after reading this article from the Telegraph about some Swedish research into cancer therapy. It's written in a breathless style - here, see for yourself:

Yet as things stand, Ad5[CgA-E1A-miR122]PTD – to give it the full gush of its most up-to-date scientific name – is never going to be tested to see if it might also save humans. Since 2010 it has been kept in a bedsit-sized mini freezer in a busy lobby outside Prof Essand's office, gathering frost. ('Would you like to see?' He raises his laptop computer and turns, so its camera picks out a table-top Electrolux next to the lab's main corridor.)
Two hundred metres away is the Uppsala University Hospital, a European Centre of Excellence in Neuroendocrine Tumours. Patients fly in from all over the world to be seen here, especially from America, where treatment for certain types of cancer lags five years behind Europe. Yet even when these sufferers have nothing else to hope for, have only months left to live, wave platinum credit cards and are prepared to sign papers agreeing to try anything, to hell with the side-effects, the oncologists are not permitted – would find themselves behind bars if they tried – to race down the corridors and snatch the solution out of Prof Essand's freezer.

(By the way, does anyone have anything to substantiate that "five years behind Europe" claim? I don't.) To be sure, Prof. Essand tries to make plain to the reporter (Alexander Masters) that this viral therapy has only been tried in animals, that a lot of things work in animals that don't work in man, and so on. But given Masters' attitude towards medical research, there's only so much that you can do:

. . .Quacks provide a very useful service to medical tyros such as myself, because they read all the best journals the day they appear and by the end of the week have turned the results into potions and tinctures. It's like Tommy Lee Jones in Men in Black reading the National Enquirer to find out what aliens are up to, because that's the only paper trashy enough to print the truth. Keep an eye on what the quacks are saying, and you have an idea of what might be promising at the Wild West frontier of medicine. . .

I have to say, in my experience, that this is completely wrong. Keep an eye on what the quacks are saying, and you have an idea of what might have been popular in 1932. Or 1954. Quacks seize onto an idea and never, ever, let it go, despite any and all evidence, so quackery is an interminable museum of ancient junk. New junk is added all the time, though, one has to admit. You might get some cutting-edge science, if your idea of cutting-edge is an advertisement in one of those SkyMall catalogs you get on airplanes. A string of trendy buzzwords super-glued together does not tell you where science is heading.

But Masters means well with this piece. He wants to see Essend's therapy tried out in the clinic, and he wants to help raise money to do that (see the end of the article, which shows how to donate to a fund at Uppsala). I'm fine with that - as far as I can tell, longer shots than this one get into the clinic, so why not? But I'd warn people that their money, as with the rest of the money we put into this business, is very much at risk. If crowdsourcing can get some ideas a toehold in the clinical world, I'm all for it, but it would be a good thing in general if people realized the odds. It would also be a good idea if more people realized how much money would be needed later on, if things start to look promising. No one's going to crowdsource a Phase III trial, I think. . . .

Comments (12) + TrackBacks (0) | Category: Cancer | Clinical Trials | Drug Development

September 6, 2012

Accelerated Approval And Its Discontents

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Posted by Derek

This may sound a little odd coming from someone in the drug industry, but I have a lot of sympathy for the FDA. I'm not saying that I always agree with them, or that I think that they're doing exactly what we need them to do all the time. But I would hate to be the person that would have to decide how they should do things differently. And I think that no matter what, the agency is going to have a lot of people with reasons to complain.

These thoughts are prompted by this article in JAMA on whether or not drug safety is being compromised by the growing number of "Priority Review" drug approvals. There are three examples set out in detail: Caprelsa (vandetanib) for thyroid cancer, Gilenya (fingolimod) for multiple sclerosis, and the anticoagulant Pradaxa (dabigatran). In each of these accelerated cases, safety has turned out to be more of a concern than some people expected, and the authors of this paper are asking if the benefits have been worth the risks.

Pharmalot has a good summary of the paper, along with a reply from the FDA. Their position is that various forms of accelerated approval have been around for quite a few years now, and that the agency is committed to post-approval monitoring in these cases. What they don't say - but it is, I think, true - is that there is no way to have accelerated approvals without occasional compromises in drug safety. Can't be done. You have to try to balance these things on a drug-by-drug basis: how much the new medication might benefit people without other good options, versus how many people it might hurt instead. And those are very hard calls, which are made with less data than you would have under non-accelerated conditions. If these three examples are indeed problematic drugs that made it through the system, no one should be surprised at all. Given the number of accelerated reviews over the years, there have to be some like this. In fact, this goes to show you that the accelerated review process is not, in fact, a sham. If everything that passed through it turned out to be just as clean as things that went through the normal approval process, that would be convincing evidence that the whole thing was just window dressing.

If that's true - and as I said, I certainly believe it is - then the question is "Should there be such a thing as accelerated approval at all?" If you decide that the answer to that is "Yes", then the follow-up is "Is the risk-reward slider set to the right place, or are we letting a few too many things through?" This is the point the authors are making, I'd say, that the answer to that question is "Yes", and we need to move the settings back a bit. But here comes an even trickier question: if you do that, how far back do you go before the whole accelerated approval process is not worth the effort any more? (If you try to make it so that nothing problematic makes it through at all, you've certainly crossed into that territory, to my way of thinking). So if three recent examples like these represent an unacceptable number (and it may be), what is acceptable? Two? One? Those numbers, but over a longer period of time?

And if so, how are you going to do that without tugging on the other end of the process, helping patients who are waiting for new medications? No, these are very, very hard questions, and no matter how you answer them, someone will be angry with you. I have, as I say, a lot of sympathy for the FDA.

Comments (7) + TrackBacks (0) | Category: Drug Development | Regulatory Affairs | Toxicology

September 4, 2012

A New Malaria Compound

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Posted by Derek

There have been many headlines in recent days about a potential malaria cure. I'm not sure what set these off at this time, since the paper describing the work came out back in the spring, but it's certainly worth a look.

This all came out of the Medicines for Malaria Venture, a nonprofit group that has been working with various industrial and academic groups in many areas of malaria research. This is funded through a wide range of donors (corporations, foundations, international agencies), and work has taken place all over the world. In this case (PDF), things began with a collection of about 36,000 compounds (biased towards kinase inhibitor scaffolds) from BioFocus in the UK. These were screened (high-throughput phenotypic readout) at the Eskitis Institute in Australia, and a series of compounds was identified for structure-activity studies. This phase of the work was a three-way collaboration between a chemistry team at the University of Cape Town (led by Prof. Kelly Chibale), biology assay teams at the Swiss Tropical and Public Health Institute, and pharmacokinetics at the Center for Drug Candidate Optimization at Monash University in Australia.
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An extensive SAR workup on the lead series identified some metabolically labile parts of the molecule over on that left-hand side pyridine. These could fortunately be changed without impairing the efficacy against the malaria parasites. The sulfonyl group seems to be required, as does the aminopyridine. These efforts led to the compound shown, MMV390048, which has good blood levels, passes in vitro safety tests, and is curative in a Plasmodium berghei mouse model at a single dose of 30 mg/kg. That's a very promising compound, from the looks of it, since that's better than the existing antimalarials can do. It's also active against drug-resistant strains, as well it might be (see below). Last month the MMV selected it for clinical development.

So how does this compound work? The medicinal chemists in the audience will have looked at that structure and said "kinase inhibitor", and that has to be where to put your money. That, in fact, appears to have been the entire motivation to screen the BioFocus collection. Kinase targets in Plasmodium have been getting attention for several years now; the parasite has a number of enzymes in this class, and they're different enough from human kinases to make attractive targets. (To that point, I have not been able to find results of this latest compound's profile when run against a panel of human kinases, although you'd think that this has surely been done by now). Importantly, none of the existing antimalarials work through such mechanisms, so the parasites have not had a chance to work up any resistance.

But resistance will come. It always does. The best hope for the kinase-based inhibitors is that they'll hit several malaria enzymes at once, which gives the organisms a bigger evolutionary barrier to jump over. The question is whether you can do that without hitting anything bad in the human kinome, but for the relatively short duration of acute malaria treatment, you should be able to get away with quite a bit. Throwing this compound and the existing antimalarials at the parasites simultaneously will really give them something to occupy themselves.

I'll follow the development of this compound with interest. It's just about to hit the really hard part of drug research - human beings in the clinic. This is where we have our wonderful 90% or so failure rates, although those figures are generally better for anti-infectives, as far as I can tell. Best of luck to everyone involved. I hope it works.

Comments (27) + TrackBacks (0) | Category: Drug Development | Infectious Diseases

August 31, 2012

Eli Lilly's Drumbeat of Bad News

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Posted by Derek

Eli Lilly has been getting shelled with bad news recently. There was the not-that-encouraging-at-all failure of its Alzheimer's antibody solanezumab to meet any of its clinical endpoints. But that's the good news, since that (at least according to the company) it showed some signs of something in some patients.

We can't say that about pomaglumetad methionil (LY2140023), their metabotropic glutamate receptor ligand for schizophrenia, which is being halted. The first large trial of the compound failed to meet its endpoint, and an interim analysis showed that the drug was unlikely to have a chance of making its endpoints in the second trial. It will now disappear, as will the money spent on it so far. (The first drug project I ever worked on was a backup for an antipsychotic with a novel mechanism, which also failed to do a damned thing in the clinic, and which experience perhaps gave me some of the ideas I have now about drug research).

This compound is an oral prodrug of LY404039, which has a rather unusual structure. The New York Times did a story about the drug's development a few years ago, which honestly makes rather sad reading in light of the current news. It was once thought to have great promise. Note the cynical statement in that last link about how it really doesn't matter if the compound works or not - but you know what? It did matter in the end. This was the first compound of its type, an attempt at a real innovation through a new mechanism to treat mental illness, just the sort of thing that some people will tell you that the drug industry never gets around to doing.

And just to round things off, Lilly announced the results of a head-to-head trial of its anticoagulant drug Effient versus (now generic) Plavix in acute coronary syndrome. This is the sort of trial that critics of the drug industry keep saying never gets run, by the way. But this one was, because Plavix is the thing to beat in that field - and Effient didn't beat it, although there might have been an edge in long-term followup.

Anticoagulants are a tough field - there are a lot of patients, a lot of money to be made, and a lot of room (in theory) for improvement over the existing agents. But just beating heparin is hard enough, without the additional challenge of beating cheap Plavix. It's a large enough patient population, though, that more than one drug is needed because of different responses.

There have been a lot of critics of Lilly's research strategy over the years, and a lot of shareholders have been (and are) yelling for the CEO's head. But from where I sit, it looks like the company has been taking a lot of good shots. They've had a big push in Alzheimer's, for example. Their gamma-secretase inhibitor, which failed in terrible fashion, was a first of its kind. Someone had to be the first to try this mechanism out; it's been a goal of Alzheimer's research for over twenty years now. Solanezumab was a tougher call, given the difficulties that Elan (and Wyeth/Pfizer, J&J, and so on) have had with that approach over the years. But immunology is a black box, different antibodies do different things in different people, and Lilly's not the only company trying the same thing. And they've been doggedly pursuing beta-secretase as well. These, like them or not, are still some of the best ideas that anyone has for Alzheimer's therapy. And any kind of win in that area would be a huge event - I think that Lilly deserves credit for having the nerve to go after such a tough area, because I can tell you that I've been avoiding it ever since I worked on it in the 1990s.

But what would I have spent the money on instead? It's not like there are any low-risk ideas crowding each other for attention. Lilly's portfolio is not a crazy or stupid one - it's not all wild ideas, but it's not all full of attempts to play it safe, either. It looks like the sort of thing any big (and highly competent) drug research organization could have ended up with. The odds are still very much against any drug making it through the clinic, which means that having three (or four, or five) in a row go bad on you is not an unusual event at all. Just a horribly unprofitable one.

Comments (26) + TrackBacks (0) | Category: Cardiovascular Disease | Clinical Trials | Drug Development | Drug Industry History | The Central Nervous System

August 29, 2012

How Did the Big Deals of 2007 Work Out?

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Posted by Derek

Startup biopharma companies: they've gotta raise money, right? And the more money, the better, right? Not so right, according to this post by venture capitalist Bruce Booth. Companies need money, for sure, but above a certain threshold there's no correlation with success, either for the company's research portfolio or its early stage investors. (I might add that the same holds true for larger drug companies as well, for somewhat different reasons. Perhaps Pfizer's strategy over the last twenty years has had one (and maybe only one) net positive effect: it's proven that you cannot humungous your way to success in this business. And yes, since you ask, that's the last time I plan to use "humungous" as a verb for a while).

There's also a fascinating look back at FierceBiotech's 2007 "Top Deals", to see what became of the ten largest financing rounds on the list. Some of them have worked out, and some of them most definitely haven't: 4 of the ten were near-total losses. One's around break-even, two are "works in progress" but could come through, and three have provided at least 2x returns. (Read his post to attach names to these!) And as Booth shows, that's pretty much what you'd expect from the distribution over the entire biotech industry, including all the wild-eyed stuff and the riskiest small fry. Going with the biggest, most lucratively financed companies bought you, in this case, no extra security at all.

A note about those returns: one of the winners on the list is described as having paid out "modest 2x returns" to the investors. That's the sort of quote that inspires outrage among the clueless, because (of course) a 100% profit is rather above the market returns for the last five years. But the risk/reward ratio has not been repealed. You could have gotten those market returns by doing nothing, just by parking the cash in a couple of index funds and sitting back. Investing in startup companies requires a lot more work, because you're taking on a lot more risk.

It was not clear which of those ten big deals in 2007 would pay out, to put it mildly. In fact, if you take Booth's figures so far, an equal investment in each of the top seven companies on the list in 2007 would leave you looking at a slight net loss to date, and that includes one company that would have paid you back at about 3x to 4x. Number eight was the big winner on the list (5x, if you got out at the perfect peak, and good luck with that), and number 9 is the 2x return (while #10 is ongoing, but a likely loss). As any venture investor knows, you're looking at a significant risk of losing your entire investment whenever you back a startup, so you'd better (a) back more than one and (b) do an awful lot of thinking about which ones those are. This is a job for the deeply pocketed.

And when you think about it, a very similar situation obtains inside a given drug company. The big difference is that you don't have the option of not playing the game - something always has to be done. There are always projects going, some of which look more promising than others, some of which will cost more to prosecute than others, and some of which are aimed at different markets than others. You might be in a situation where there are several that look like they could be taken on, but your development organization can't handle so many. What to do? Partner something, park something that can wait (if anything can)?Or you might have the reverse problem, of not enough programs that look like they might work. Do you push the best of a bad lot forward and hope for the best? If not, do you still pay your development people even if they have nothing to develop right now, in the hopes that they soon will?

Which of these clinical programs of yours have the most risk? The biggest potential? Have you balanced those properly? You're sure to lose your entire investment on the majority - the great majority - of them, so choose as wisely as you can. The ones that make it through are going to have to pay for all the others, because if they don't, everyone's out of a job.

This whole process, of accumulating capital and risking it on new ventures, is important enough that we've named an entire economic system for it. It's a high-wire act. Too cautious, and you might not keep up enough to survive. Too risky, and you could lose too much. They do focus one's attention, such prospects, and the thought that other companies are out there trying to get a step on you helps keep you moving, too. It's not a pretty system, but it isn't supposed to be. It's supposed to work.

Comments (1) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

August 23, 2012

Pharma: Geniuses or Con Men?

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Posted by Derek

So here's a comment to this morning's post on stock buybacks, referring both to it and my replies to Donald Light et al. last week. I've added links:

Did you not spend two entire posts last week telling readers how only pharma "knows" how to do drug research and that we should "trust" them and their business model. Now you seem to say that they are either incompetent or conmen looking for a quick buck. So what is it? Does pharma (as it exists today) have a good business model or are they conmen/charlatans out for money? Do they "know" what they are doing? Or are they faking competence?

False dichotomy. My posts on the Donald Light business were mostly to demonstrate that his ideas of how the drug industry works are wrong. I was not trying to prove that the industry itself is doing everything right.

That's because it most certainly isn't. But it is the only biopharma industry we have, and before someone comes along with a scheme to completely rework it, one should ask whether that's a good idea. In this very context, the following quote from Chesterton has been brought up, and it's very much worth keeping in mind:

In the matter of reforming things, as distinct from deforming them, there is one plain and simple principle; a principle which will probably be called a paradox. There exists in such a case a certain institution or law; let us say, for the sake of simplicity, a fence or gate erected across a road. The more modern type of reformer goes gaily up to it and says, "I don't see the use of this; let us clear it away." To which the more intelligent type of reformer will do well to answer: "If you don't see the use of it, I certainly won't let you clear it away. Go away and think. Then, when you can come back and tell me that you do see the use of it, I may allow you to destroy it."

This paradox rests on the most elementary common sense. The gate or fence did not grow there. It was not set up by somnambulists who built it in their sleep. It is highly improbable that it was put there by escaped lunatics who were for some reason loose in the street. Some person had some reason for thinking it would be a good thing for somebody. And until we know what the reason was, we really cannot judge whether the reason was reasonable. It is extremely probable that we have overlooked some whole aspect of the question, if something set up by human beings like ourselves seems to be entirely meaningless and mysterious. There are reformers who get over this difficulty by assuming that all their fathers were fools; but if that be so, we can only say that folly appears to be a hereditary disease. But the truth is that nobody has any business to destroy a social institution until he has really seen it as an historical institution. If he knows how it arose, and what purposes it was supposed to serve, he may really be able to say that they were bad purposes, that they have since become bad purposes, or that they are purposes which are no longer served. But if he simply stares at the thing as a senseless monstrosity that has somehow sprung up in his path, it is he and not the traditionalist who is suffering from an illusion.

The drug industry did not arise out of random processes; it looks the way it does now because of a long, long series of decisions. Because we live in a capitalist system, many of these decisions were made to answer the question "Which way would make more money?" That is not guaranteed to give you the best outcome. But neither is it, as some people seem to think, a guarantee of the worst one. Insofar as the need for new and effective drugs is coupled to the ability to make money by doing so, I think the engine works about as well as anything could. Where these interests decouple (tropical diseases, for one), we need some other means.

My problem with stock buybacks is that I think that executives are looking at that same question ("Which way would make more money?") and answering it incorrectly. But under current market conditions, there are many values of "wrong". In the long run, I think (as does Bruce Booth) that it would be more profitable, both for individual companies and for the industry as a whole, to invest more in research. In fact, I think that's the only thing that's going to get us out of the problems that we're in. We need to have more reliable, less expensive ways to discover and develop drugs, and if we're not going to find those by doing research on how to make them happen, then we must be waiting for aliens to land and tell us.

But that long run is uncertain, and may well be too long for many investors. Telling the shareholders that Eventually Things Will Be Better, We Think, Although We're Not Sure How Just Yet will not reassure them, especially in this market. Buying back shares, on the other hand, will.

Comments (22) + TrackBacks (0) | Category: Business and Markets | Drug Development

August 21, 2012

Genentech's Big Worry: Roche?

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Posted by Derek

There's no telling if this is true - it's part of a lawsuit. But a former Genentech employee is claiming that the company rushed trials of its PI3K inhibitor. And why? Worries about their partner:

The suit alleges that the Pi3 Kinase team was guilty of "illegal and unethical conduct" by skirting established scientific and ethical standards required of drug researchers. Juliet Kniley claims she complained in 2008 and then was sidelined in 2009 with a demotion after being instructed to push ahead on the study. And she says she was told twice that Roche would "take this molecule away from us" if they saw her proposed timelines.

Genentech denies the allegations. But you have to wonder if there's still a window here into the relationship between the two companies. . .

Comments (24) + TrackBacks (0) | Category: Drug Development

August 17, 2012

Good Forum for a Response on Drug Innovation?

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Posted by Derek

I wanted to mention that a version of my first post on the Light/Lexchin article is now up over at the Discover magazine site. And if you've been following the comments to that one and to Light's response here, you'll note that readers here have found a number of problems with the original paper's analysis. I've found a few of my own, and I expect there are more.

The British Medical Journal has advised me that they consider a letter to the editor to be the appropriate forum for a response to one of their published articles. I don't think publishing this one did them much credit, but what's done is done. I'm still shopping for a venue for a detailed response on my part - I've had a couple of much-appreciated offers, but I'd like to continue to see what options are out there to get this out to the widest possible audience.

Comments (22) + TrackBacks (0) | Category: Drug Development | Drug Prices

August 15, 2012

A Quick Tour Through Drug Development Reality

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Posted by Derek

I wanted to let people know that I'm working on a long, detailed reply to Donald Light's take on drug research, but that I'm also looking at a few other publication venues for it. More on this as it develops.

But in trying to understand his worldview (and Marcia Angell's, et al.), I think I've hit on at least one fundamental misconception that these people have. All of them seem to think that the key step in drug discovery is target ID - once you've got a molecular target, you're pretty much home free, and all that was done by NIH money, etc., etc. It seems that these people have a very odd idea about high-throughput screening: they seem to think that we screen our vast collections of molecules and out pops a drug.

Of course, out is what a drug does not pop, if you follow my meaning. What pops out are hits, some of which are not what they say on the label any more. And some of the remaining ones just don't reproduce when you run the same experiment again. And even some of the ones that do reproduce are showing up as hits not because they're affecting your target, but because they're hosing up your assay by some other means. Once you've cleared all that underbrush out, you can start to talk about leads.

Those lead molecules are not created equal, either. Some of them are more potent than others, but the more potent ones might be much higher molecular weights (and thus not as ligand efficient). Or they might be compounds from another project and already known to hit a target that you don't want to hit. Once you pick out the ones that you actually want to do some chemistry on, you may find, as you start to test new molecules in the series, that some of them have more tractable structure-activity relationships than others. There are singletons out there, or near-singletons: compounds that have some activity as they stand, but for which every change in structure represents a step down. The only way to find that out is to test analogs. You might have some more in your files, or you might be able to buy some from the catalogs. But in many cases, you'll have to make them yourself, and a significant number of those compounds you make will be dead ends. You need to know which ones, though, so that's valuable information.

Now you're all the way up to lead series territory, a set of compounds that look like they can be progressed to be more potent and more selective. As medicinal chemists know, though, there's more to life. You need to see how these compounds act on real cells, and in real animals. Do they attain reasonable blood levels? Why or why not? What kinds of metabolites do they produce - are those going to cause trouble? What sort of toxicity do you see at higher doses, or more long-running ones? Is that related to your mechanism of action (sorry to hear it!), or something off-target to do with that particular structure? Can you work your way out of that problem with more new compound variations without losing all of what you've been building in so far? Prepare to go merrily chasing down some blind alleys while you work all this stuff out; the lights are turned off inside the whole maze, and the only illumination is what you can bring yourself.

Now let's assume that you've made it far enough to narrow down to one single compound, the clinical candidate. The fun begins! How about formulations - can this compound be whipped up into a solid form that resembles a real drug that people can put in their mouths, leave on their medicine cabinet shelves, and stock in their warehouses and pharmacies? Can you make enough of the compound to get to that stage, reliably? Most of the time the chemistry has to change at that point, and you'd better hope that some tiny new impurities from the new route aren't going to pop up and be important. You'd really better hope that some new solid form (polymorph) of your substance doesn't get discovered during that new route, because some of those are bricks and their advent is nearly impossible to predict.

Hey, now it's time to go to the clinic. Break out the checkbook, because the money spent here is going to make the preclinical expenses look like roundoff errors. Real human beings are going to take your compound, and guess what? Of all the compounds (the few, the proud) that actually get this far, all the way up to some volunteer's tongue. . .well, a bit over ninety per cent of those are going to fail in trials. Good luck!

While you're nervously checking the clinical results (blood levels and tolerability in Phase I), you have more questions to ask. Do you have good commercial suppliers for all the starting materials, and the right manufacturing processes in place to make the drug, formulate it, and package it? High time you thought about that stuff; your compound is about to go into the first sick humans it's ever seen, in Phase II. You finally get to find out if that target, that mechanism, actually works in people. And if it does (congratulations!), then comes the prize. You get to spend the real money in Phase III: lots and lots of patients, all sorts of patients, in what's supposed to be a real-world shakedown. Prepare to shell out more than you've spent in the whole process to date, because Phase III trials will empty your pockets for sure.

Is your compound one of the five or ten out of a hundred that makes it through Phase III? Enjoy the sensation, because most medicinal chemists experience that only once in their careers, if that. Now you're only a year or two away from getting your drug through the FDA and seeing if it will succeed or fail on the market. And good luck there, too. Contrary to what you might read, not all drugs earn back their costs, so the ones that do had better earn out big-time.

There. That wasn't so easy, was it? And I know that I've left things out, too. The point of all this is that most people have no idea of all these steps - what they're like, how long they can take, that they even exist. It wouldn't surprise me if many people imagine drug discovery, when they imagine it at all, to be the reach-in-the-pile-and-find-a-drug process that I mentioned in the second paragraph. Everything else is figuring out what color to make the package and how much to overcharge for it.

That's why I started this blog back in 2002 - because I was spending all my time on a fascinating, tricky, important job that no one seemed to know anything about. All these details consume the lives and careers of vast numbers of researchers - it's what I've been doing since 1989 - and I wanted, still want, to let people know that we exist.

In the meantime, for the Donald Lights of the world, the Marcia Angells, and the people who repeat their numbers despite apparently knowing nothing about how drugs actually get developed - well, here are some more details for you. The readers of this site with experience in the field will be able to tell you if I haven't described it pretty much as it is. It's not like I and others haven't tried to tell you before.

Comments (60) + TrackBacks (0) | Category: Drug Development | Drug Prices

August 13, 2012

Donald Light Responds on Drug Innovation and Costs

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Posted by Derek

Here's a response from Prof. Light to my post the other day attacking his positions on drug research. I've taken it out of that comments thread to highlight it - he no longer has to wonder if I'll let people here read what he has to say.

I'll have a response as well, but that'll most likely be up tomorrow - I actually have a very busy day ahead of me in the lab, working on a target that (as far as any of us in my group can tell) no one has ever attacked, for a disease that (as far as any of us in my group can tell) no one has ever found a therapy. And no, I am not making that up.

It's hard to respond to so many sarcastic and baiting trashings by Dr. Lowe and some of his fan club, but let me try. I wonder if Dr. Lowe allows his followers to read what I write here without cutting and editing.

First, let me clarify some of the mis-representations about the new BMJ article that claims the innovation crisis is a myth. While the pharmaceutical industry and its global network of journalists have been writing that the industry has been in real trouble because innovation has been dropping, all those articles and figures are based on the decline of new molecules approved since a sharp spike. FDA figures make it clear that the so-called crisis has been simply a return to the long-term average. In fact, in recent years, companies have been getting above-average approvals for new molecules. Is there any reasonably argument with these FDA figures? I see none from Dr. Lowe or in the 15 pages of comments.

Second, the reported costs of R&D have been rising sharply, and we do not go into these; but here are a couple of points. We note that the big picture, total additional investments in R&D (which are self-reported from closely held figures) over the past 15 years were matched by six times greater increase in revenues. We can all guess various reasons why, but surely a 6-fold return is not a crisis or "unsustainable." In fact, it's evidence that companies know what they are doing.

Another point from international observers is that the costs of clinical trials in the U.S. are much higher than in equally affluent countries and much higher than they need to be, because everyone seems to make money the higher they are in the U.S. market. I have not looked into this but I think it would be interesting to see in what ways costly clinical trials are a boon for several of the stakeholders.

Third, regarding that infamously low cost of R&D that Dr. Lowe and readers like to slam, consider this: The low estimate is based on the same costs of R&D reported by companies (which are self-reported from closely held figures) to their leading policy research center as were used to estimate the average cost is $1.3 bn (and soon to be raised again). Doesn't that make you curious enough to want to find out how we show what inflators were used to ramp the reported costs up, which use to do the same in reverse? Would it be unfair to ask you to actually read how we took this inflationary estimate apart? Or is it easier just to say our estimate is "idiotic" and "absurd"? How about reading the whole argument at www.pharmamyths.net and then discuss its merits?

Our estimate is for net, median corporate cost of D(evelopment) for that same of drugs from the 1990s that the health economists supported by the industry used to ramp up the high estimate. Net, because taxpayer subsidies which the industry has fought hard to expand pay for about 44% of gross R&D costs. Median, because a few costly cases which are always featured raise the average artificially. Corporate, because a lot of R(eseach) and some D is paid for by others "“ governments, foundations, institutes. We don't include an estimate for R(eseach) because no one knows what it is and it varies so much from a chance discovery that costs almost nothing to years and decades of research, failures, dead ends, new angles, before finally an effective drug is discovered.

So it's an unknown and highly variable R plus more knowable estimate of net, median, corporate costs. Even then, companies never so show their books, and they never compare their costs of R&D to revenues and profits. They just keep telling us their unverifiable costs of R&D are astronomical.

We make clear that neither we nor anyone else knows either the average gross cost or the net, median costs of R&D because major companies have made sure we cannot. Further, the "average cost of R&D" estimate began in 1976 as a lobbying strategy to come up with an artificial number that could be used to wow Congressmen. It's worked wonderfully, mythic as it may be.

Current layoffs need to be considered (as do most things) from a 10-year perspective. A lot industry observers have commented on companies being "bloated" and adding too many hires. Besides trimming back to earlier numbers, the big companies increasingly realize (it has taken them years) that it's smarter to let thousands of biotechs and research teams try to find good new drugs, rather than doing it in-house. To regard those layoffs as an abandonment of research misconstrues the corporate strategies.

Fourth, we never use "me-too." We speak of minor variations, and we say it's clinically valuable to have 3-4 in a given therapeutic class, but marginal gains fall quite low after that.

Fifth, our main point about innovation is that current criteria for approval and incentives strongly reward companies doing exactly what they are doing, developing scores of minor variations to fill their sales lines and market for good profits. We don't see any conspiracy here, only rational economic behavior by smart businessmen.

But while all new drug products are better than placebo or not too worse than a comparator, often against surrogate end points, most of those prove to be little better than last year's "better" drugs, or the years before"¦ You can read detailed assessments by independent teams at several sites. Of course companies are delighted when new drugs are really better against clinical outcomes; but meantime we cite evidence that 80 percent of additional pharmaceutical costs go to buying newly patented minor variations. The rewards to do anything to get another cancer drug approved are so great that independent reviewers find few of them help patients much, and the area is corrupted by conflict-of-interest marketing.

So we conclude there is a "hidden business model" behind the much touted business model, to spend billions on R&D to discover breakthrough drugs that greatly improve health and works fine until the "patent cliff" sends the company crashing to the canyon floor. The heroic tale is true to some extent and sometimes; but the hidden business model is to develop minor variations and make solid profits from them. That sounds like rational economic behavior to me.
The trouble is, all these drugs are under-tested for risks of harm, and all drugs are toxic to one degree or another. My book, The Risks of Prescription Drugs, assembles evidence that there is an epidemic of harmful side effects, largely from hundreds of drugs with few or no advantages to offset their risks of harm.

Is that what we want? My neighbors want clinically better drugs. They think the FDA approves clinically better drugs and don't realize that's far from the case. Most folks think "innovation" means clinically superior, but it doesn't. Most new molecules do not prove to be clinically superior. The term "innovation" is used vaguely to signal better drugs for patients; but while many new drugs are technically innovative, they do not help patients much. The false rhetoric of "innovative" and "innovation" needs to be replaced by what we want and mean: "clinically superior drugs."

If we want clinically better drugs, why don't we ask for them and pay according to added value "“ no more if no better and a lot more if substantially better? Instead, standards for testing effectiveness and risk of harms is being lowered, and "“ guess what "“ that will reward still more minor variations by rational economic executives, not more truly superior "innovative" drugs.

I hope you find some of these points worthwhile and interesting. I'm trying to reply to 20 single-space pages of largely inaccurate criticism, often with no reasoned explanation for a given slur or dismissal. I hope we can do better than that. I thought the comments by Matt #27 and John Wayne #45 were particularly interesting.

Donald W. Light

Comments (71) + TrackBacks (0) | Category: "Me Too" Drugs | Drug Development | Drug Prices

August 9, 2012

Getting Drug Research Really, Really Wrong

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Posted by Derek

The British Medical Journal says that the "widely touted innovation crisis in pharmaceuticals is a myth". The British Medical Journal is wrong.

There, that's about as direct as I can make it. But allow me to go into more detail, because that's not the the only thing they're wrong about. This is a new article entitled "Pharmaceutical research and development: what do we get for all that money?", and it's by Joel Lexchin (York University) and Donald Light of UMDNJ. And that last name should be enough to tell you where this is all coming from, because Prof. Light is the man who's publicly attached his name to an estimate that developing a new drug costs about $43 million dollars.

I'm generally careful, when I bring up that figure around people who actually develop drugs, not to do so when they're in the middle of drinking coffee or working with anything fragile, because it always provokes startled expressions and sudden laughter. These posts go into some detail about how ludicrous that number is, but for now, I'll just note that it's hard to see how anyone who seriously advances that estimate can be taken seriously. But here we are again.

Light and Lexchin's article makes much of Bernard Munos' work (which we talked about here), which shows a relatively constant rate of new drug discovery. They should go back and look at his graph, because they might notice that the slope of the line in recent years has not kept up with the historical rate. And they completely leave out one of the other key points that Munos makes: that even if the rate of discovery were to have remained linear, the costs associated with it sure as hell haven't. No, it's all a conspiracy:

"Meanwhile, telling "innovation crisis" stories to politicians and the press serves as a ploy, a strategy to attract a range of government protections from free market, generic competition."

Ah, that must be why the industry has laid off thousands and thousands of people over the last few years: it's all a ploy to gain sympathy. We tell everyone else how hard it is to discover drugs, but when we're sure that there are no reporters or politicians around, we high-five each other at how successful our deception has been. Because that's our secret, according to Light and Lexchin. It's apparently not any harder to find something new and worthwhile, but we'd rather just sit on our rears and crank out "me-too" medications for the big bucks:

"This is the real innovation crisis: pharmaceutical research and development turns out mostly minor variations on existing drugs, and most new drugs are not superior on clinical measures. Although a steady stream of significantly superior drugs enlarges the medicine chest from which millions benefit, medicines have also produced an epidemic of serious adverse reactions that have added to national healthcare costs".

So let me get this straight: according to these folks, we mostly just make "minor variations", but the few really new drugs that come out aren't so great either, because of their "epidemic" of serious side effects. Let me advance an alternate set of explanations, one that I call, for lack of a better word, "reality". For one thing, "me-too" drugs are not identical, and their benefits are often overlooked by people who do not understand medicine. There are overcrowded therapeutic areas, but they're not common. The reason that some new drugs make only small advances on existing therapies is not because we like it that way, and it's especially not because we planned it that way. This happens because we try to make big advances, and we fail. Then we take what we can get.

No therapeutic area illustrates this better than oncology. Every new target in that field has come in with high hopes that this time we'll have something that really does the job. Angiogenesis inhibitors. Kinase inhibitors. Cell cycle disruptors. Microtubules, proteosomes, apoptosis, DNA repair, metabolic disruption of the Warburg effect. It goes on and on and on, and you know what? None of them work as well as we want them to. We take them into the clinic, give them to terrified people who have little hope left, and we watch as we provide with them, what? A few months of extra life? Was that what we were shooting for all along, do we grin and shake each others' hands when the results come in? "Another incremental advance! Rock and roll!"

Of course not. We're disappointed, and we're pissed off. But we don't know enough about cancer (yet) to do better, and cancer turns out to be a very hard condition to treat. It should also be noted that the financial incentives are there to discover something that really does pull people back from the edge of the grave, so you'd think that we money-grubbing, public-deceiving, expense-padding mercenaries might be attracted by that prospect. Apparently not.

The same goes for Alzheimer's disease. Just how much money has the industry spent over the last quarter of a century on Alzheimer's? I worked on it twenty years ago, and God knows that never came to anything. Look at the steady march, march, march of failure in the clinic - and keep in mind that these failures tend to come late in the game, during Phase III, and if you suggest to anyone in the business that you can run an Alzheimer's Phase III program and bring the whole thing in for $43 million dollars, you'll be invited to stop wasting everyone's time. Bapineuzumab's trials have surely cost several times that, and Pfizer/J&J are still pressing on. And before that you had Elan working on active immunization, which is still going on, and you have Lilly's other antibody, which is still going on, and Genentech's (which is still going on). No one has high hopes for any of these, but we're still burning piles of money to try to find something. And what about the secretase inhibitors? How much time and effort has gone into beta- and gamma-secretase? What did the folks at Lilly think when they took their inhibitor way into Phase III only to find out that it made Alzheimer's slightly worse instead of helping anyone? Didn't they realize that Professors Light and Lexchin were on to them? That they'd seen through the veil and figured out the real strategy of making tiny improvements on the existing drugs that attack the causes of Alzheimer's? What existing drugs to target the causes of Alzheimer are they talking about?

Honestly, I have trouble writing about this sort of thing, because I get too furious to be coherent. I've been doing this sort of work since 1989, and I have spent the great majority of my time working on diseases for which no good therapies existed. The rest of the time has been spent on new mechanisms, new classes of drugs that should (or should have) worked differently than the existing therapies. I cannot recall a time when I have worked on a real "me-too" drug of the sort of that Light and Lexchin seem to think the industry spends all its time on.

That's because of yet another factor they have not considered: simultaneous development. Take a look at that paragraph above, where I mentioned all those Alzheimer's therapies. Let's be wildly, crazily optimistic and pretend that bapineuzumab manages to eke out some sort of efficacy against Alzheimer's (which, by the way, would put it right into that "no real medical advance" category that Light and Lexchin make so much of). And let's throw caution out the third-floor window and pretend that Lilly's solanezumab actually does something, too. Not much - there's a limit to how optimistic a person can be without pharmacological assistance - but something, some actual efficacy. Now here's what you have to remember: according to people like the authors of this article, whichever of these antibodies that makes it though second is a "me-too" drug that offers only an incremental advance, if anything. Even though all this Alzheimer's work was started on a risk basis, in several different companies, with different antibodies developed in different ways, with no clue as to who (if anyone) might come out on top.

All right, now we get to another topic that articles like this latest one are simply not complete without. That's right, say it together: "Drug companies spend a lot more on marketing than they do on research!" Let's ignore, for the sake of argument, the large number of smaller companies that spend all of their money on R&D and none on marketing, because they have nothing to market yet. Let's even ignore the fact that over the years, the percentage of money being spent on drug R&D has actually been going up. No, let's instead go over this in a way that even professors at UMDNJ and York can understand it:

Company X spends, let's say, $10 a year on research. (We're lopping off a lot of zeros to make this easier). It has no revenues from selling drugs yet, and is burning through its cash while it tries to get its first on onto the market. It succeeds, and the new drug will bring in $100 dollars a year for the first two or three years, before the competition catches up with some of the incremental me-toos that everyone will switch to for mysterious reasons that apparently have nothing to do with anything working better. But I digress; let's get back to the key point. That $100 a year figure assumes that the company spends $30 a year on marketing (advertising, promotion, patient awareness, brand-building, all that stuff). If the company does not spend all that time and effort, the new drug will only bring in $60 a year, but that's pure profit. (We're going to ignore all the other costs, assuming that they're the same between the two cases).

So the company can bring in $60 dollars a year by doing no promotion, or it can bring in $70 a year after accounting for the expenses of marketing. The company will, of course, choose the latter. "But," you're saying, "what if all that marketing expense doesn't raise sales from $60 up to $100 a year?" Ah, then you are doing it wrong. The whole point, the raison d'etre of the marketing department is to bring in more money than they are spending. Marketing deals with the profitable side of the business; their job is to maximize those profits. If they spend more than those extra profits, well, it's time to fire them, isn't it?

R&D, on the other hand, is not the profitable side of the business. Far from it. We are black holes of finance: huge sums of money spiral in beyond our event horizons, emitting piteous cries and futile streams of braking radiation, and are never seen again. The point is, these are totally different parts of the company, doing totally different things. Complaining that the marketing budget is bigger than the R&D budget is like complaining that a car's passenger compartment is bigger than its gas tank, or that a ship's sail is bigger than its rudder.

OK, I've spend about enough time on this for one morning; I feel like I need a shower. Let's get on to the part where Light and Lexchin recommend what we should all be doing instead:

What can be done to change the business model of the pharmaceutical industry to focus on more cost effective, safer medicines? The first step should be to stop approving so many new drugs of little therapeutic value. . .We should also fully fund the EMA and other regulatory agencies with public funds, rather than relying on industry generated user fees, to end industry’s capture of its regulator. Finally, we should consider new ways of rewarding innovation directly, such as through the large cash prizes envisioned in US Senate Bill 1137, rather than through the high prices generated by patent protection. The bill proposes the collection of several billion dollars a year from all federal and non-federal health reimbursement and insurance programmes, and a committee would award prizes in proportion to how well new drugs fulfilled unmet clinical needs and constituted real therapeutic gains. Without patents new drugs are immediately open to generic competition, lowering prices, while at the same time innovators are rewarded quickly to innovate again. This approach would save countries billions in healthcare costs and produce real gains in people’s health.

One problem I have with this is that the health insurance industry would probably object to having "several billion dollars a year" collected from it. And that "several" would not mean "two or three", for sure. But even if we extract that cash somehow - an extraction that would surely raise health insurance costs as it got passed along - we now find ourselves depending on a committee that will determine the worth of each new drug. Will these people determine that when the drug is approved, or will they need to wait a few years to see how it does in the real world? If the drug under- or overperforms, does the reward get adjusted accordingly? How, exactly, do we decide how much a diabetes drug is worth compared to one for multiple sclerosis, or TB? What about a drug that doesn't help many people, but helps them tremendously, versus a drug that's taken by a lot of people, but has only milder improvements for them? What if a drug is worth a lot more to people in one demographic versus another? And what happens as various advocacy groups lobby to get their diseases moved further up the list of important ones that deserve higher prizes and more incentives?

These will have to be some very, very wise and prudent people on this committee. You certainly wouldn't want anyone who's ever been involved with the drug industry on there, no indeed. And you wouldn't want any politicians - why, they might use that influential position to do who knows what. No, you'd want honest, intelligent, reliable people, who know a tremendous amount about medical care and pharmaceuticals, but have no financial or personal interests involved. I'm sure there are plenty of them out there, somewhere. And when we find them, why stop with drugs? Why not set up committees to determine the true worth of the other vital things that people in this country need each day - food, transportation, consumer goods? Surely this model can be extended; it all sounds so rational. I doubt if anything like it has ever been tried before, and it's certainly a lot better than the grubby business of deciding prices and values based on what people will pay for things (what do they know, anyway, compared to a panel of dispassionate experts?)

Enough. I should mention that when Prof. Light's earlier figure for drug expense came out that I had a brief correspondence with him, and I invited him to come to this site and try out his reasoning on people who develop drugs for a living. Communication seemed to dry up after that, I have to report. But that offer is still open. Reading his publications makes me think that he (and his co-authors) have never actually spoken with anyone who does this work or has any actual experience with it. Come on down, I say! We're real people, just like you. OK, we're more evil, fine. But otherwise. . .

Comments (75) + TrackBacks (0) | Category: "Me Too" Drugs | Business and Markets | Cancer | Drug Development | Drug Industry History | Drug Prices | The Central Nervous System | Why Everyone Loves Us

July 16, 2012

AstraZeneca Admits It Spent Too Much Money

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Posted by Derek

Looks like AstraZeneca's internal numbers agree with Matthew Herper's. The company was talking about its current R&D late last week, and this comment stands out:

Discovery head Mene Pangalos told reporters on Thursday that mistakes had been in the past by encouraging quantity over quality in early drug selection.

"If you looked at our output in terms of numbers of candidates entering the clinic, we were one of the most productive companies in the world, dollar for dollar. If you rated us by how many drugs we launched, we were one of the least successful," he said.

Yep, sending compounds to the clinic is easy - you just declare them to be Clinical Candidates, and the job is done. Getting them through the clinic, now, that's harder, because at that point you're encountering things that can't be rah-rah-ed. Viruses and bacteria, neurons and receptors and tumor cells, they don't care so much about your goals statement and your Corporate Commitment to Excellence. In the end, that's one of the things I like most about research: the real world has the last laugh.

The news aggregator Biospace has a particularly misleading headline on all this: "AstraZeneca Claims Neuroscience Shake-Up is Paying Off ; May Advance at Least 8 Drugs to Final Tests by 2015". I can't find anyone from AZ putting it in quite those terms, fortunately. That would be like saying that my decision, back in Boston, to cut costs by not filling my gas tank is paying off as I approach Philadelphia.

Comments (27) + TrackBacks (0) | Category: Business and Markets | Clinical Trials | Drug Development

June 26, 2012

The Next Five Years in the Drug Industry

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Posted by Derek

Nature Reviews Drug Discovery has an article on the current state of drug development, looking at what's expected to be launched from 2012 to 2016. There's a lot of interesting information, but this is the sentence that brought me up short: "the global pipeline has stopped growing". The total number of known projects in the drug industry (preclinical to Phase III) now appears to have peaked in 2009, at just over 7700. It's now down to 7400, and the biggest declines are in the early stages, so the trend is going to continue for a while.

But before we all hit the panic button, it looks like this is a somewhat artificial decline, since it was based on an artificial peak. In 2006, the benchmark year for the 2007-2011 cohort of launched drugs, there were only about 6100 projects going. I'm not sure what led to the rise over the next three years after that, but we're still running higher. So while I can't say that it's healthy that the number of projects has been declining, we may be largely looking at some sort of artifact in the data. Worth keeping an eye on.

And the authors go on to say that this larger number of new projects, compared to the previous five-year period, should in fact lead to a slight rise in the number of new drugs approved, even if you assume that the success rates drop off a bit. They're guessing 30 to 35 launches per year, well above the post-2000 average. Peak sales for these new products, though, are probably not going to match the historical highs, so that needs to be taken into account.

More data: the coming cohort of new drugs is expected to be a bit more profitable, and a bit more heavily weighted towards small molecules rather than biologics. Two-thirds of the revenues from this coming group are expected to be from drugs that are already in some sort of partnership arrangement, and you'd have to think that this number will increase further for the later-blooming candidates. The go-it-alone blockbuster compound really does seem to be a relative rarity - the complexity and cost of large clinical trials, and the worldwide regulatory and marketing landscape have seen to that.

As for therapeutic area, oncology has the highest number of compounds in development (26% of them as of 2011). It's to the point that the authors wonder if there's an "oncology bubble" on the way, since there are between 2 and 3 compounds chasing each major oncology target. Personally, I think that these compounds are probably still varied enough to make places for themselves, considering the wildly heterogeneous nature of the market. But it's going to be a messy process, figuring out what compounds are useful for which cases.

So in the near term, overall, it looks like things are going to hold together. Past that five-year mark, though, predictions get fuzzier, and the ten-year situation is impossible to forecast at all. That, in fact, is going to be up to those of us doing early research. The shape we're in by that time will be determined, perhaps, by what we go out into the labs and do today. I have a tool compound to work up, to validate (I hope) an early assay, and another project to pay attention to this afternoon. 2022 is happening now.

Update: here are John LaMattina's thoughts on this analysis, asking about some things that may not have been taken into account.

Comments (16) + TrackBacks (0) | Category: Business and Markets | Drug Development

June 13, 2012

Live By The Bricks, Die By The Bricks

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Posted by Derek

I wanted to highlight a couple of recent examples from the literature to show what happens (all too often) when you start to optimize med-chem compounds. The earlier phases of a project tend to drive on potency and selectivity, and the usual way to get these things is to add more stuff to your structures. Then as you start to produce compounds that make it past those important cutoffs, your focus turns more to pharmacokinetics and metabolism, and sometimes you find you've made your life rather difficult. It's an old trap, and a well-known one, but that doesn't stop people from sticking a leg into it.

Take a look at these two structures from ACS Chemical Biology. The starting structure is a pretty generic-looking kinase inhibitor, and as the graphic to its left shows, it does indeed hit a whole slew of kinases. These authors extended the structure out to another loop of the their desired target, c-Src, and as you can see, they now have a much more selective compound.
kinase%20inhibitor.png
But at such a price! Four more aromatic rings, including the dread biphenyl, and only one sp3 carbon in the lot. The compound now tips the scales at MW 555, and looks about as soluble as the Chrysler building. To be fair, this is an academic group, which mean that they're presumably after a tool compound. That's a phrase that's used to excuse a lot of sins, but in this case they do have cellular assay data, which means that despite this compound's properties, it's managing to do something. Update: see this comment from the author on this very point. Be warned, though, if you're in drug discovery and you follow this strategy. Adding four flat rings and running up the molecular weight might work for you, but most of the time it will only lead to trouble - pharmacokinetics, metabolic clearance, toxicity, formulation.

My second example is from a drug discovery group (Janssen). They report work on a series of gamma-secretase modulators (GSMs) for Alzheimer's. You can tell from the paper that they had quite a wild ride with these things - for one, the activity in their mouse model didn't seem to correlate at all with the concentration of the compounds in the brain. Looking at those structures, though, you have to think that trouble is lurking, and so it is.
secretase.png

"In all chemical classes, the high potency was accompanied by high lipophilicity (in general, cLogP >5) and a TPSA [topological polar surface area] below 75 Å, explaining the good brain penetration. However, the majority of compounds also suffered from hERG binding with IC50s below 1 μM, CyP inhibition and low solubility, particularly at pH = 7.4 (data not shown). These unfavorable ADME properties can likely be attributed to the combination of high lipophilicity and low TPSA.

That they can. By the time they got to that compound 44, some of these problems had been solved (hERG, CyP). But it's still a very hard-to-dose compound (they seem to have gone with a pretty aggressive suspension formulation) and it's still a greasy brick, despite its impressive in vivo activity. And that's my point. Working this way exposes you to one thing after another. Making greasy bricks often leads to potent in vitro assay numbers, but they're harder to get going in vivo. And if you get them to work in the animals, you often face PK and metabolic problems. And if you manage to work your way around those, you run a much higher risk of nonspecific toxicity. So guess what happened here? You have to go to the very end of the paper to find out:

As many of the GSMs described to date, the series detailed in this paper, including 44a, is suffering from suboptimal physicochemical properties: low solubility, high lipophilicity, and high aromaticity. For 44a, this has translated into signs of liver toxicity after dosing in dog at 20 mg/kg. Further optimization of the drug-like properties of this series is ongoing.

Back to the drawing board, in other words. I wish them luck, but I wonder how much of this structure is going to have to be ripped up and redone in order to get something cleaner?

Comments (38) + TrackBacks (0) | Category: Alzheimer's Disease | Cancer | Drug Development | Pharmacokinetics | Toxicology

June 12, 2012

Predicting Toxicology

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Posted by Derek

One of the major worries during a clinical trial is toxicity, naturally. There are thousands of reasons a compound might cause problem, and you can be sure that we don't have a good handle on most of them. We screen for what we know about (such as hERG channels for cardiovascular trouble), and we watch closely for signs of everything else. But when slow-building low-incidence toxicity takes your compound out late in the clinic, it's always very painful indeed.

Anything that helps to clarify that part of the business is big news, and potentially worth a lot. But advanced in clinical toxicology come on very slowly, because the only thing worse than not knowing what you'll find is thinking that you know and being wrong. A new paper in Nature highlights just this problem. The authors have a structural-similarity algorithm to try to test new compounds against known toxicities in previously tested compounds, which (as you can imagine) is an approach that's been tried in many different forms over the years. So how does this one fare?

To test their computational approach, Lounkine et al. used it to estimate the binding affinities of a comprehensive set of 656 approved drugs for 73 biological targets. They identified 1,644 possible drug–target interactions, of which 403 were already recorded in ChEMBL, a publicly available database of biologically active compounds. However, because the authors had used this database as a training set for their model, these predictions were not really indicative of the model's effectiveness, and so were not considered further.

A further 348 of the remaining 1,241 predictions were found in other databases (which the authors hadn't used as training sets), leaving 893 predictions, 694 of which were then tested experimentally. The authors found that 151 of these predicted drug–target interactions were genuine. So, of the 1,241 predictions not in ChEMBL, 499 were true; 543 were false; and 199 remain to be tested. Many of the newly discovered drug–target interactions would not have been predicted using conventional computational methods that calculate the strength of drug–target binding interactions based on the structures of the ligand and of the target's binding site.

Now, some of their predictions have turned out to be surprising and accurate. Their technique identified chlorotrianisene, for example, as a COX-1 inhibitor, and tests show that it seems to be, which wasn't known at all. The classic antihistamine diphenhydramine turns out to be active at the serotonin transporter. It's also interesting to see what known drugs light up the side effect assays the worst. Looking at their figures, it would seem that the topical antiseptic chlorhexidine (a membrane disruptor) is active all over the place. Another guanidine-containing compound, tegaserod, is also high up the list. Other promiscuous compounds are the old antipsychotic fluspirilene and the semisynthetic antibiotic rifaximin. (That last one illustrates one of the problems with this approach, which the authors take care to point out: toxicity depends on exposure. The dose makes the poison, and all that. Rifaximin is very poorly absorbed, and it would take very unusual dosing, like with a power drill, to get it to hit targets in a place like the central nervous system, even if this technique flags them).

The biggest problem with this whole approach is also highlighted by the authors, to their credit. You can see from those figures above that about half of the potentially toxic interactions it finds aren't real, and you can be sure that there are plenty of false negatives, too. So this is nowhere near ready to replace real-world testing; nothing is. But where it could be useful is in pointing out things to test with real-world assays, activities that you probably hadn't considered at all.

But the downside of that is that you could end up chasing meaningless stuff that does nothing but put the fear into you and delays your compound's development, too. That split, "stupid delay versus crucial red flag", is at the heart of clinical toxicology, and is the reason it's so hard to make solid progress in this area. So much is riding on these decisions: you could walk away from a compound, never developing one that would go on to clear billions of dollars and help untold numbers of patients. Or you could green-light something that would go on to chew up hundreds of millions of dollars of development costs (and even more in opportunity costs, considering what you could have been working on instead), or even worse, one that makes it onto the market and has to be withdrawn in a blizzard of lawsuits. It brings on a cautious attitude.

Comments (21) + TrackBacks (0) | Category: Drug Development | In Silico | Toxicology

June 5, 2012

Merck Finds Its Phase II Candidates For Sale on the Internet

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Posted by Derek

Via Pharmalot, it appears that a former WuXi employee helped himself to samples of two Merck Phase II clinical candidates that were under evaluation. The samples were then offered for sale.

Here's a link to a Google Translate version of a Chinese news report. It looks like gram quantities were involved, along with NMR spectra, with the compounds being provided to a middleman. It's not clear who bought them from him, but the article gives the impression that someone did, was satisfied with the transaction, and wanted more. But in the meantime, Merck did pick up on an offer made by this middleman to sell one of the compounds online, and immediately went after him, which unraveled the whole scheme. (The machine translation is pretty rocky, but I did appreciate that an idiom came through: it mentions that having these valuable samples in an unlocked cabinet was like putting fish in front of a cat).

I would think that this kind of thing is just the nightmare that WuXi's management fears - and if it isn't, it should be. The cost advantage to doing business with them (and other offshore contract houses) is still real, but not as large as it used to be. Stories like this can close that price gap pretty quickly.

Comments (45) + TrackBacks (0) | Category: Business and Markets | Drug Development | The Dark Side

June 4, 2012

Scaling Up Arteminisin

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Posted by Derek

A recent article in Science illustrates a number of points about drug development and scale-up. It's about artemisinin, the antimalarial. Peter Seeberger, a German professor of chemistry (Max Planck-Potsdam), has worked out what looks like a good set of conditions for a key synthetic step (dihydroartemisinic acid to artemisinin), and would like to see these used on large scale to bring the cost of the drug down.

That sounds like a reasonably simple story, but it isn't. Here are a few of the complications:

But Seeberger's method has yet to prove its mettle. It needs to be scaled up, and he can't say how much prices would come down if it worked. Using it in a large facility would require a massive investment, and so far, nobody has stepped up to the plate. What's more, pharma giant Sanofi will open a brand-new facility later this year to make artemisinin therapies based on Amyris's technology: yeast cells that produce a precursor of the drug. Although Seeberger says his discovery would complement that process, Sanofi says it's too late now to adopt it.

The usual route has been to extract arteminisin from its source, Artemisia annua. That's been quite a boom-and-bust cycle over the years, and the price has never really been steady (or particularly low, either). Amyris worked for some years to engineer yeast to produce artemisinic acid, which can then be extracted and converted into the final drug, and this is what's now being scaled up with Sanofi-Aventis.

That process also uses a photochemical oxidation, but in batch mode. I'm a big fan of flow chemistry, and I've done some flow photochemistry myself, and I can agree that when it's optimized, it can be a great improvement over such batch conditions. Seeberger's method looks promising, but Sanofi isn't ready to retool to use it when they have their current conditions worked out. Things seem to be at an impass:

But what will happen with Seeberger's discovery is still unclear. Sanofi's plant is about to open, and the company isn't going to bet on an entirely new technique that has yet to prove that it can be scaled up. In an e-mail to Science, the company calls Seeberger's solution “a clever approach,” but says that “so far the competitivity of this technique has not been demonstrated.”

The ideal solution would be if other companies adopt the combination of Amyris's yeast cells and Seeberger's method, [Michigan supply-chain expert] Yadav says; “then, the price for the drugs could go down significantly.” But a spokesperson for OneWorld Health, the nonprofit pharmaceutical company that has backed Sanofi's project, says there are no plans to make the yeast cells available to any other party.

Seeberger himself is trying to make something happen:

On 19 April, Seeberger invited interested parties to a meeting in Berlin to explore the options. They included representatives of Artemisia growers and extractors, pharmaceutical companies GlaxoSmithKline and Boehringer Ingelheim, as well as the Clinton Foundation, UNITAID, and the German Agency for International Cooperation. (The Bill and Melinda Gates Foundation canceled at the last minute.) None of the funders wanted to discuss the meeting with Science. Seeberger says he was asked many critical questions—“But then the next day, my phone did not stop ringing.” He is now in discussions with several interested parties, he says.

As I say, I like his chemistry. But I can sympathize with the Sanofi people as well. Retooling a working production route is not something you undertake lightly, and the Seeberger chemistry will doubtless need some engineering along the way to reach its potential. The best solution seems to me to be basically what's happening: Sanofi cranks out the drug using its current process, which should help a great deal with the supply in the short term. Meanwhile, Seeberger tries to get his process ready for the big time, with the help of an industrial partner. I wish him luck, and I hope things don't stall out along the way. More on all this as it develops over the next few months.

Comments (22) + TrackBacks (0) | Category: Drug Development

May 24, 2012

An Oral Insulin Pill?

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Posted by Derek

Bloomberg has an article on Novo Nordisk and their huge ongoing effort to come up with an orally available form of insulin. That's been a dream for a long time now, but it's always been thought to be very close to impossible. The reasons for this are well known: your gut will treat a big protein like insulin pretty much like it treats a hamburger. It'll get digested, chopped into its constituent amino acids, and absorbed as non-medicinally-active bits which are used as raw material once inside the body. That's what digestion is. The gut wall specifically guards against letting large biomolecules through intact.

So you're up against a lot of defenses when you try to make something like oral insulin. Modifying the protein itself to make it more permeable and stable will be a big part of it, and formulating the pill to escape the worst of the gut environments will be another. Even then, you have to wonder about patient-to-patient variability in digestion, intestinal flora, and so on. The dosing is probably going to have to be pretty strict with respect to meals (and the content of those meals).

But insulin dosing is always going to be strict, because there's a narrow window to work in. That's one of the factors that's helped to sink so many other alternative-dosing schemes for it, most famously Pfizer's Exubera. The body's response to insulin in brittle in the extreme. If you take twice as much antihistamine as you should, you may feel funny. If you take twice as much insulin as you should, you're going to be on the floor, and you may stay there.

So I salute Novo Nordisk for trying this. The rewards will be huge if they get it to work, but it's a long way from working just yet.

Comments (32) + TrackBacks (0) | Category: Diabetes and Obesity | Drug Development | Pharmacokinetics

May 23, 2012

Another Vote Against Rhodanines

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Posted by Derek

For those of you who'd had to explain to colleagues (in biology or chemistry) why you're not enthusiastic about the rhodanine compounds that came out of your high-throughput screening effort, there's now another paper to point them to.

The biological activity of compounds possessing a rhodanine moiety should be considered very critically despite the convincing data obtained in biological assays. In addition to the lack of selectivity, unusual structure–activity relationship profiles and safety and specificity problems mean that rhodanines are generally not optimizable.

That's well put, I think, although this has been a subject of debate. I would apply the same language to the other "PAINS" mentioned in the Baell and Holloway paper, which brought together a number of motifs that have set off alarm bells over the years. These structures are guilty until proven innocent. If you have a high-value target and feel that it's worth the time and trouble to prove them so, that may well be the right decision. But if you have something else to advance, you're better off doing so. As I've said here before, ars longa, pecunia brevis.

Comments (3) + TrackBacks (0) | Category: Drug Assays | Drug Development

May 22, 2012

The NIH's Drug Repurposing Initiative: Will It Be a Waste?

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Posted by Derek

The NIH's attempt to repurpose shelved development compounds and other older drugs is underway:

The National Institutes of Health (NIH) today announced a new plan for boosting drug development: It has reached a deal with three major pharmaceutical companies to share abandoned experimental drugs with academic researchers so they can look for new uses. NIH is putting up $20 million for grants to study the drugs.

"The goal is simple: to see whether we can teach old drugs new tricks," said Health and Human Services Secretary Kathleen Sebelius at a press conference today that included officials from Pfizer, AstraZeneca, and Eli Lilly. These companies will give researchers access to two dozen compounds that passed through safety studies but didn't make it beyond mid-stage clinical trials. They shelved the drugs either because they didn't work well enough on the disease for which they were developed or because a business decision sidelined them.

There are plenty more where those came from, and I certainly wish people luck finding uses for them. But I've no idea what the chances for success might be. On the one hand, having a compound that's passed all the preclinical stages of development and has then been into humans is no small thing. On that ever-present other hand, though, randomly throwing these compounds against unrelated diseases is unlikely to give you anything (there aren't enough of them to do that). My best guess is that they have a shot in closely related disease fields - but then again, testing widely might show us that there are diseases that we didn't realized were related to each other.

John LaMattina is skeptical:

Well, the NIH has recently expanded the remit of NCATS. NCATS will now be testing drugs that have been shelved by the pharmaceutical industry for other potential uses. The motivation for this is simple. They believe that these once promising but failed compounds could have other uses that the inventor companies haven’t yet identified. I’d like to reiterate the view of Dr. Vagelos – it’s fairy time again.

My views on this sort of initiative, which goes by a variety of names – “drug repurposing,” “drug repositioning,” “reusable drugs” – have been previously discussed in my blog. I do hope that people can have success in this type of work. But I believe successes are going to be rare.

The big question is, rare enough to count the money and time as wasted, or not? I guess we'll find out. Overall, I'd rather start with a compound that I know does what I want it to do, and then try to turn it into a drug (phenotypic screening). Starting with a compound that you know is a drug, but doesn't necessarily do what you want it to, is going to be tricky.

Comments (33) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development | Drug Industry History

May 21, 2012

A New Way to Kill Amoebas, From An Old Drug

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Posted by Derek

Here's a good example of phenotypic screening coming through with something interesting and worthwhile: they screened against Entamoeba histolytica, the protozooan that causes amoebic dysentery and kills tens of thousands of people every year. (Press coverage here).

It wasn't easy. The organism is an anaerobe, which is a bad fit for most robotic equipment, and engineering a decent readout for the assay wasn't straightforward, either. They did have a good positive control, though - the nitroimidazole drug metronidazole, which is the only agent approved currently against the parasite (and to which it's becoming resistant). A screen of nearly a thousand known drugs and bioactive compounds showed eleven hits, of which one (auranofin) was much more active than metronidazole itself.

Auranofin's an old arthritis drug. It's a believable result, because the compound has also been shown to have activity against trypanosomes, Leishmania parasites, and Plasmodium malaria parasites. This broad-spectrum activity makes some sense when you realize that the drug's main function is to serve as a delivery vehicle for elemental gold, whose activity in arthritis is well-documented but largely unexplained. (That activity is also the basis for persistent theories that arthritis may have an infectious-disease component).

The target in this case may well be arsenite-inducible RNA-associated protein (AIRAP), which was strongly induced by drug treatment. The paper notes that arsenite and auranofin are both known inhibitors of thioredoxin reductase, which strongly suggests that this is the mechanistic target here. The organism's anaerobic lifestyle fits in with that; this enzyme would presumably be its main (perhaps only) path for scavenging reactive oxygen species. It has a number of important cysteine residues, which are very plausible candidates for binding to a metal like gold. And sure enough, auranofin (and two analogs) are potent inhibitors of purified form of the amoeba enzyme.

The paper takes the story all the way to animal models, where auranofin completely outperforms metronidazole. The FDA has now given it orphan-drug status for amebiasis, and the way appears clear for a completely new therapeutic option in this disease. Congratulations to all involved; this is excellent work.

Comments (10) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development | Infectious Diseases

A Molecular Craigslist?

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Posted by Derek

Mat Todd at the University of Sydney (whose open-source drug discovery work on schistosomiasis I wrote about here) has an interesting chemical suggestion. His lab is also involved in antimalarial work (here's an update, for those interested, and I hope to post about this effort more specifically). He's wondering about whether there's room for a "Molecular Craigslist" for efforts like these:

Imagine there is a group somewhere with expertise in making these kinds of compounds, and who might want to make some analogs as part of a student project, in return for collaboration and co-authorship? What about a Uni lab which might be interested in making these compounds as part of an undergrad lab course?

Wouldn’t it be good if we could post the structure of a molecule somewhere and have people bid on providing it? i.e. anyone can bid – commercial suppliers, donators, students?

Is there anything like this? Well, databases like Zinc and Pubchem can help in identifying commercial suppliers and papers/patents where groups have made related compounds, but there’s no tendering process where people can post molecules they want. Science Exchange has, I think, commercial suppliers, but not a facility to allow people to donate (I may be wrong), or people to volunteer to make compounds (rather than be listed as generic suppliers. Presumably the same goes for eMolecules, and Molport?

Is there a niche here for a light client that permits the process I’m talking about? Paste your Smiles, post the molecule, specifying a purpose (optional), timeframe, amount, type of analytical data needed, and let the bidding commence?

The closest thing I can think of is Innocentive, which might be pretty close to what he's talking about. It's reasonably chemistry-focused as well. Any thoughts out there?

Comments (19) + TrackBacks (0) | Category: Academia (vs. Industry) | Business and Markets | Drug Development | Infectious Diseases

May 17, 2012

A Preventative Trial for Alzheimer's: The Right Experiment

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Posted by Derek

Alzheimer's disease is in the news, as the first major preventative drug trial gets underway. I salute the people who have made this happen, because we're bound to learn a lot from the attempt, even while I fear the chances for success are not that good.

A preventative trial for Alzheimer's would, under normal circumstances, be a nightmarish undertaking. The disease is quite variable and comes on slowly, and it's proven very difficult to predict who might start to show symptoms as they age. You'd be looking at dosing a very large number of people (thousands, even tens of thousands?) for a very long time (years, maybe a decade or two?) in order to have a chance at statistical significance. And you would, in the course of things, be giving a lot of drug to a lot of people who (in the end) would have turned out not to need it. No, it's no surprise that no one's gone that route.

But there's a way out of that impasse: find a population with some sort of amyloid-pathway mutation. Now you know exactly who will come down with symptoms, and (unfortunately) you also know that they're going to come down with them earlier and more quickly as well. There are several of these around the world; the "Swedish" and "Dutch" mutations are probably the most famous. There's a Colombian mutation too, with a well-defined patient population that's been studied for years, and that's where this new study will take place.

About 300 people will be given an experimental antibody therapy to amyloid protein, crenezumab. This was developed by AC Immune in Switzerland and licensed to Genentech, and is one of many amyloid-targeted antibodies that have come along over the years. (The best-known is bapineuzumab, currently in Phase III). Genentech (Roche) will be putting up the majority of the money for the trial ($65 million, with $16 million from the NIH and $15 million in private foundation money). Just in passing, weren't some people trying to convince everyone a year ago that it only costs $43 million total to develop a new drug? Har, har.

100 people with the mutation will get the antibody every two weeks, and 100 more will get placebo. There are also 100 non-carriers mixed in, who will all get placebo, because some carriers have indicated that they don't want to know their status. Everyone will go through a continuing battery of cognitive and psychological tests, as well as brain imaging and a great deal of blood work, which (if we're lucky) could furnish tips towards clinical biomarkers for future trials.

So overall, I think that this trial is an excellent idea, and I very much hope that a lot of useful information comes out of it. But I've no firm hopes that it will pan out therapeutically. This will be a direct test of the amyloid hypothesis for Alzheimer's, and although there's a tremendous amount of evidence for that line of thought, there's a lot against it as well. Anyone who really thinks they know what will happen in this situation hasn't thought hard enough about it. But that's the best kind of experiment, isn't it?

Comments (18) + TrackBacks (0) | Category: Alzheimer's Disease | Clinical Trials | Drug Development

May 11, 2012

Competitive Intelligence: Too Much or Too Little?

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Posted by Derek

Drug companies are very attuned to competitive intelligence. There's a lot of information sloshing around out there, and you'd be wise to pay attention to it. Publications in journals are probably the least of it - by the time something written up for publication from inside a pharma company, it's either about to be on the drugstore shelves or it never will be at all. Patents are far more essential, and if you're going to watch anything, you should watch the patent applications in your field.

But there's more. Meetings are a big source of disclosure, as witness the Wall Street frenzies around ASCO and the like. Talks and posters release information that won't show up in the literature for a long time (if indeed it ever does). And there are plenty of other avenues. The question is, though, how much time and money do you want to spend on this sort of thing?

There are commercial services (such as Integrity) that monitor companies, compounds, and therapeutic areas in this fashion, and they're happy to sell you their services, which are not cheap. But figuring out the cost/benefit ratio isn't easy. My guess is that these things, while useful, can be thought of as insurance. You're paying to make sure that something big doesn't happen that you're unware or (or unaware of in enough time).

So here's a question for the readership: has competitive intelligence ever made a big difference for you? Positive and negative results both welcome; "I'm so glad we found out about X" versus "I really wish we'd known about Y". Any thoughts?

Comments (15) + TrackBacks (0) | Category: Drug Development

May 3, 2012

A Long-Delayed COX2 Issue Gets Settled - For $450 Million?

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Posted by Derek

Has the last shot been fired, very quietly, in the COX-2 discovery wars? Here's the background, in which some readers of this site have probably participated at various times. Once it was worked out that the nonsteroidal antiinflammatory drugs (aspirin, ibuprofen et al.) were inhibitors of the enzyme cyclooxygenase, it began to seem likely that there were other forms of the enzyme as well. But for a while, no one could put their hands on one. That changed in the early 1990s, when Harvey Herschman at UCLA reported the mouse COX2 gene. The human analog was discovered right on the heels of that one, with priority usually given to Dan Simmons of BYU, with Donald Young of the University of Rochester there at very nearly the same time.

The Rochester story is one that many readers will be familiar with. The university, famously, obtained a patent for compounds that exerted a therapeutic effect through inhibition of COX-2, without specifying what compounds those might be. They did not, in fact, have any, nor did they give any hints about what they'd look like, and this is what sank them in the end when the university lost its case against Searle (and its patent) for not fulfilling the "written description" requirement.

But there was legal action on the BYU end of things, too. Simmons and the university filed suit several years ago, saying that Simmons had entered into a contract with Monsanto in 1991 to discover COX2 inhibitors. The suit claimed that Monsanto had (wrongly) advised Simmons not to file for a patent on his discoveries, and had also reversed course, terminating the deal to concentrate on the company's internal efforts instead once it had obtained what it needed from the Simmons work.

That takes us to the tangled origin of the COX2 chemical matter. The progenitor compound is generally taken to be DuP-697, which was discovered and investigated before the COX-2 enzyme was even characterized. The compound had a strong antiinflammatory profile which was nonetheless different from the NSAIDS, which led to strong suspicions that it was indeed acting through the putative "other cyclooxygenase". And so it proved, once the enzyme was discovered, and a look at its structure versus the marketed drugs shows that it was a robust series of structures indeed.

One big difference between the BYU case and the Rochester case was the Simmons did indeed have a contract, and it was breach-of-contract that formed the basis for the suit. The legal maneuverings have been going on for several years now. But now Pfizer has issued a press release saying that they have reached "an amicable settlement on confidential terms". The only real detail given is that they're going to establish the Dan Simmons Chair at BYU in recognition of his work.

But there may be more to it than that. Pfizer has also reported taking a $450 million charge against earnings related to this whole matter, which certainly makes one think of Latin sayings, among them post hoc, ergo propter hoc and especially quid pro quo. We may not ever get the full details, since part of the deal would presumably include not releasing them. But it looks like a substantial sum has changed hands.

Comments (12) + TrackBacks (0) | Category: Drug Development | Drug Industry History | Patents and IP

April 30, 2012

India's First Drug Isn't India's First Drug

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Posted by Derek

There have been a number of headlines the last few days about Ranbaxy's Synriam, an antimalarial that's being touted as the first new drug developed inside the Indian pharma industry (and Ranbaxy as the first Indian company to do it).

But that's not quite true, as this post from The Allotrope makes clear. (Its author, Akshat Rathi, found one of my posts when he started digging into the story). Yes, Synriam is a mixture of a known antimalarial (piperaquine) and arterolane. And arterolane was definitely not discovered in India. It was part of a joint effort from the US, UK, Australia, and Switzerland, coordinated by the Swiss-based Medicines for Malaria Venture.

Ranbaxy did take on the late-stage development of this drug combination, after MMV backed out due to no-so-impressive performance in the clinic. As Rathi puts it:

Although Synriam does not qualify as ‘India’s first new drug’ (because none of its active ingredients were wholly developed in India), Ranbaxy deserves credit for being the first Indian pharmaceutical company to launch an NCE before it was launched anywhere else in the world.

And that's something that not many countries have done. I just wish that Ranbaxy were a little more honest about that in their press release.

Comments (8) + TrackBacks (0) | Category: Drug Development | Infectious Diseases

April 12, 2012

A Federation of Independent Researchers?

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Posted by Derek

I've had an interesting e-mail from a reader who wants to be signed as "Mrs. McGreevy", and it's comprehensive enough that I'm going to reproduce it in full below.

As everyone but the editorial board of C&E News has noticed, jobs in chemistry are few and far between right now. I found your post on virtual biotechs inspiring, but it doesn't look like anyone has found a good solution for how to support these small firefly businesses until they find their wings, so to speak. Lots of editorials, lots of meetings, lots of rueful headshaking, no real road map forward for unemployed scientists.

I haven't seen this proposed anywhere else, so I'm asking you and your readership if this idea would fly:

What about a voluntary association of independent research scientists?

I'm thinking about charging a small membership fee (for non-profit administration and hard costs) and using group buying power for the practical real-world support a virtual biotech would need:

1. Group rates on health and life insurance.

How many would-be entrepreneurs are stuck in a job they hate because of the the health care plan, or even worse, are unemployed or underemployed and uninsurable, quietly draining their savings accounts and praying no one gets really sick? I have no idea how this would work across state lines, or if it is even possible,but would it hurt to find out? Is anyone else looking?

2. Group rates on access to journals and library services.

This is something I do know a bit about. My M.S. is in library science, and I worked in the Chemistry Library in a large research institution for years during grad school. What if there were one centralized virtual library to which unaffiliated researchers across the country could log in for ejournal access? What if one place could buy and house the print media that start-ups would need to access every so often, and provide a librarian to look things up-- it's not like everyone needs their own print copy of the Canada & US Drug Development Industry & Outsourcing Guide 2012 at $150 a pop. (But if 350 people paid $1 a year for a $350/yr online subscription . . . )

Yes, some of you could go to university libraries and look these things up and print off articles to read at home, but some of you can't. You're probably violating some sort of terms of service agreement the library and publisher worked out anyway. It's not like anyone is likely to bust you unless you print out stacks and stacks of papers, but still. It's one more hassle for a small company to deal with, and everyone will have to re-invent the wheel and waste time and energy negotiating access on their own.

3. How about an online community for support and networking-- places for blogs, reviews, questions, answers, exchanges of best practices, or even just encouragement for that gut-wrenching feeling of going out on your own as a new entrepreneur?

4. What sort of support for grantwriting is out there? Is there a hole that needs to be filled?

5. How about a place to advertise your consulting services or CRO, or even bid for a contract? Virtual RFP posting?

6. Would group buying power help negotiate rates with CROs? How about rates for HTS libraries, for those of you who haven't given up on it completely?

Is there a need for this sort of thing? Would anyone use it if it were available? How much would an unaffiliated researcher be willing to pay for the services? Does anyone out there have an idea of what sort of costs are involved, and what sort of critical mass it would take to achieve the group buying power needed to make this possible?

I'd be happy to spark a discussion on what a virtual biotech company needs besides a spare bedroom and a broadband connection, even if the consensus opinion is that the OP an ill-informed twit with an idea that will never fly. What do you need to get a virtual biotech started? How do we make it happen? There are thousands of unemployed lab scientists, and I refuse to believe that the only guy making a living these days from a small independently-funded lab is Bryan Cranston.

A very worthy topic indeed, and one whose time looks to have come. Thoughts on how to make such a thing happen?

Comments (59) + TrackBacks (0) | Category: Business and Markets | Drug Development | General Scientific News | The Scientific Literature

April 4, 2012

The Artificial Intelligence Economy?

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Posted by Derek

Now here's something that might be about to remake the economy, or (on the other robotic hand) it might not be ready to just yet. And it might be able to help us out in drug R&D, or it might turn out to be mostly beside the point. What the heck am I talking about, you ask? The so-called "Artificial Intelligence Economy". As Adam Ozimek says, things are looking a little more futuristic lately.

He's talking about things like driverless cars and quadrotors, and Tyler Cowen adds the examples of things like Apple's Siri and IBM's Watson, as part of a wider point about American exports:

First, artificial intelligence and computing power are the future, or even the present, for much of manufacturing. It’s not just the robots; look at the hundreds of computers and software-driven devices embedded in a new car. Factory floors these days are nearly empty of people because software-driven machines are doing most of the work. The factory has been reinvented as a quiet place. There is now a joke that “a modern textile mill employs only a man and a dog—the man to feed the dog, and the dog to keep the man away from the machines.”

The next steps in the artificial intelligence revolution, as manifested most publicly through systems like Deep Blue, Watson and Siri, will revolutionize production in one sector after another. Computing power solves more problems each year, including manufacturing problems.

Two MIT professors have written a book called Race Against the Machine about all this, and it appears to be sort of a response to Cowen's earlier book The Great Stagnation. (Here's an article of theirs in The Atlantic making their case).

One of the export-economy factors that it (and Cowen) bring up is that automation makes a country's wages (and labor costs in general) less of a factor in exports, once you get past the capital expenditure. And as the size of that expenditure comes down, it becomes easier to make that leap. One thing that means, of course, is that less-skilled workers find it harder to fit in. Here's another Atlantic article, from the print magazine, which looked at an auto-parts manufacturer with a factory in South Carolina (the whole thing is well worth reading):

Before the rise of computer-run machines, factories needed people at every step of production, from the most routine to the most complex. The Gildemeister (machine), for example, automatically performs a series of operations that previously would have required several machines—each with its own operator. It’s relatively easy to train a newcomer to run a simple, single-step machine. Newcomers with no training could start out working the simplest and then gradually learn others. Eventually, with that on-the-job training, some workers could become higher-paid supervisors, overseeing the entire operation. This kind of knowledge could be acquired only on the job; few people went to school to learn how to work in a factory.
Today, the Gildemeisters and their ilk eliminate the need for many of those machines and, therefore, the workers who ran them. Skilled workers now are required only to do what computers can’t do (at least not yet): use their human judgment.

But as that article shows, more than half the workers in that particular factory are, in fact, rather unskilled, and they make a lot more than their Chinese counterparts do. What keeps them employed? That calculation on what it would take to replace them with a machine. The article focuses on one of those workers in particular, named Maddie:

It feels cruel to point out all the Level-2 concepts Maddie doesn’t know, although Maddie is quite open about these shortcomings. She doesn’t know the computer-programming language that runs the machines she operates; in fact, she was surprised to learn they are run by a specialized computer language. She doesn’t know trigonometry or calculus, and she’s never studied the properties of cutting tools or metals. She doesn’t know how to maintain a tolerance of 0.25 microns, or what tolerance means in this context, or what a micron is.

Tony explains that Maddie has a job for two reasons. First, when it comes to making fuel injectors, the company saves money and minimizes product damage by having both the precision and non-precision work done in the same place. Even if Mexican or Chinese workers could do Maddie’s job more cheaply, shipping fragile, half-finished parts to another country for processing would make no sense. Second, Maddie is cheaper than a machine. It would be easy to buy a robotic arm that could take injector bodies and caps from a tray and place them precisely in a laser welder. Yet Standard would have to invest about $100,000 on the arm and a conveyance machine to bring parts to the welder and send them on to the next station. As is common in factories, Standard invests only in machinery that will earn back its cost within two years. For Tony, it’s simple: Maddie makes less in two years than the machine would cost, so her job is safe—for now. If the robotic machines become a little cheaper, or if demand for fuel injectors goes up and Standard starts running three shifts, then investing in those robots might make sense.

At this point, some similarities to the drug discovery business will be occurring to readers of this blog, along with some differences. The automation angle isn't as important, or not yet. While pharma most definitely has a manufacturing component (and how), the research end of the business doesn't resemble it very much, despite numerous attempts by earnest consultants and managers to make it so. From an auto-parts standpoint, there's little or no standardization at all in drug R&D. Every new drug is like a completely new part that no one's ever built before; we're not turning out fuel injectors or alternators. Everyone knows how a car works. Making a fundamental change in that plan is a monumental challenge, so the auto-parts business is mostly about making small variations on known components to the standards of a given customer. But in pharma - discovery pharma, not the generic companies - we're wrenching new stuff right out of thin air, or trying to.

So you'd think that we wouldn't be feeling the low-wage competitive pressure so much, but as the last ten years have shown, we certainly are. Outsourcing has come up many a time around here, and the very fact that it exists shows that not all of drug research is quite as bespoke as we might think. (Remember, the first wave of outsourcing, which is still very much a part of the business, was the move to send the routine methyl-ethyl-butyl-futile analoging out somewhere cheaper). And this takes us, eventually, to the Pfizer-style split between drug designers (high-wage folks over here) and the drug synthesizers (low-wage folks over there). Unfortunately, I think that you have to go the full reducio ad absurdum route to get that far, but Pfizer's going to find out for us if that's an accurate reading.

What these economists are also talking about is, I'd say, the next step beyond Moore's Law: once we have all this processing power, how do we use it? The first wave of computation-driven change happened because of the easy answers to that question: we had a lot of number-crunching that was being done by hand, or very slowly by some route, and we now had machines that could do what we wanted to do more quickly. This newer wave, if wave it is, will be driven more by software taking advantage of the hardware power that we've been able to produce.

The first wave didn't revolutionize drug discovery in the way that some people were hoping for. Sheer brute force computational ability is of limited use in drug discovery, unfortunately, but that's not always going to be the case, especially as we slowly learn how to apply it. If we really are starting to get better at computational pattern recognition and decision-making algorithms, where could that have an impact?

It's important to avoid what I've termed the "Andy Grove fallacy" in thinking about all this. I think that it is a result of applying first-computational-wave thinking too indiscriminately to drug discovery, which means treating it too much like a well-worked-out human-designed engineering process. Which it certainly isn't. But this second-wave stuff might be more useful.

I can think of a few areas: in early drug discovery, we could use help teasing patterns out of large piles of structure-activity relationship data. I know that there are (and have been) several attempts at doing this, but it's going to be interesting to see if we can do it better. I would love to be able to dump a big pile of structures and assay data points into a program and have it say the equivalent of "Hey, it looks like an electron-withdrawing group in the piperidine series might be really good, because of its conformational similarity to the initial lead series, but no one's ever gotten back around to making one of those because everyone got side-tracked by the potency of the chiral amides".

Software that chews through stacks of PK and metabolic stability data would be worth having, too, because there sure is a lot of it. There are correlations in there that we really need to know about, that could have direct relevance to clinical trials, but I worry that we're still missing some of them. And clinical trial data itself is the most obvious place for software that can dig through huge piles of numbers, because those are the biggest we've got. From my perspective, though, it's almost too late for insights at that point; you've already been spending the big money just to get the numbers themselves. But insights into human toxicology from all that clinical data, that stuff could be gold. I worry that it's been like the concentration of gold in seawater, though: really there, but not practical to extract. Could we change that?

All this makes me actually a bit hopeful about experiments like this one that I described here recently. Our ignorance about medicine and human biochemistry is truly spectacular, and we need all the help we can get in understanding it. There have to be a lot of important things out there that we just don't understand, or haven't even realized the existence of. That lack of knowledge is what gives me hope, actually. If we'd already learned what there is to know about discovering drugs, and were already doing the best job that could be done, well, we'd be in a hell of a fix, wouldn't we? But we don't know much, we're not doing it as well as we could, and that provides us with a possible way out of the fix we're in.

So I want to see as much progress as possible in the current pattern-recognition and data-correlation driven artificial intelligence field. We discovery scientists are not going to automate ourselves out of business so quickly as factory workers, because our work is still so hypothesis-driven and hard to define. (For a dissenting view, with relevance to this whole discussion, see here). It's the expense of applying the scientific method to human health that's squeezing us all, instead, and if there's some help available in that department, then let's have it as soon as possible.

Comments (32) + TrackBacks (0) | Category: Drug Assays | Drug Development | Drug Industry History | In Silico | Pharmacokinetics | Toxicology

March 28, 2012

Winning Ugly and Failing Gracefully

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Posted by Derek

A recent discussion with colleagues turned around the question: "Would you rather succeed ugly or fail gracefully?" In drug discovery terms, that could be rephrased "Would you rather get a compound through the clinic after wrestling with a marginal structure, worrying about tox, having to fix the formulation three times, and so on, or would you rather work on something that everyone agrees is a solid target, with good chemical matter, SAR that makes sense, leading to a potent, selective, clean compound that dies anyway in Phase II?"

I vote for option number one, if those are my choices. But here's the question at the heart of a lot of the debates about preclinical criteria: do more programs like that die, or do more programs like option number two die? I tend to think that way back early in the process, when you're still picking leads, that you're better off with non-ugly chemical matter. We're only going to make it bigger and greasier, so start with as pretty a molecule as you can. But as things go on, and as you get closer to the clinic, you have to face up to the fact that no matter how you got there, no one really knows what's going to happen once you're in humans. You don't really know if your mechanism is correct (Phase II), and you sure don't know if you're going to see some sort of funny tox or long-term effect (Phase III). The chances of those are still higher if your compound is exceptionally greasy, so I think that everyone can agree that (other things being equal) you're better off with a lower logP. But what else can you trust? Not much.

The important thing is getting into the clinic, because that's where all the big questions are answered. And it's also where the big money is spent, so you have to be careful, on the other side of the equation, and not just shove all kinds of things into humans. You're going to run out of time and cash, most likely, before something works. But if you kill everything off before it gets that far, you're going to run out of both of those, too, for sure. You're going to have to take some shots at some point, and those will probably be with compounds that are less than ideal. A drug is a biologically active chemical compound that has things wrong with it.

There's another component to that "fail gracefully" idea, though, and it's a less honorable one. In a large organization, it can be to a person's advantage to make sure that everything's being done in the approved way, even if that leads off the cliff eventually. At least that way you can't be blamed, right? So you might not think that an inhibitor of Target X is such a great idea, but the committee that proposes new targets does, so you keep your head down. And you may wonder about the way the SAR is being prosecuted, but the official criteria say that you have to have at least so much potency and at least so much selectivity, so you do what you have to to make the cutoffs. And on it goes. In the end, you deliver a putative clinical candidate that may not have much of a chance at all, but that's not your department, because all the boxes got checked. More to the point, all the boxes were widely seen to be checked. So if it fails, well, it's just one of those things. Everyone did everything right, everyone met the departmental goals: what else can you do?

This gets back to the post the other day on unlikely-looking drug structures. There are a lot of them; I'll put together a gallery soon. But I think it's important to look these things over, and to realize that every one of them is out there on the market. They're on the pharmacy shelves because someone had the nerve to take them into the clinic, because someone was willing to win with an ugly compound. Looking at them, I realize that I would have crossed off billions of dollars just because I didn't feel comfortable with these structures, which makes me wonder if I haven't been overvaluing my opinion in these matters. You can't get a drug on the market without offending someone, and it may be you.

Comments (36) + TrackBacks (0) | Category: Drug Development | Life in the Drug Labs

March 27, 2012

Virtual Biotech, Like It or Not

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Posted by Derek

We've all been hearing for a while about "virtual biotechs". The term usually refers to a company with only a handful of employees and no real laboratory space of its own. All the work is contracted out. That means that what's left back at the tiny headquarters (which in a couple of cases is as small as one person's spare bedroom) is the IP. What else could it be? There's hardly any physical property at all. It's as pure a split as you can get between intellectual property (ideas, skills, actual patents) and everything else. Here's a 2010 look at the field in San Diego, and here's a more recent look from Xconomy. (I last wrote about the topic here).

Obviously, this gets easier to do earlier in the whole drug development process, where less money is involved. That said, there are difficulties at both ends. A large number of these stories seem to involve people who were at a larger company when it ran out of money, but still had some projects worth looking at. The rest of the cases seem to come out of academia. In other words, the ideas themselves (the key part of the whole business) were generated somewhere with more infrastructure and funding. Trying to get one of these off the ground otherwise would be a real bootstrapping problem.

And at the other end of the process, getting something all the way through the clinic like this also seems unlikely. The usual end point is licensing out to someone with more resources, as this piece from Xconomy makes clear:

In the meantime, one biotech model gaining traction is the single asset, infrastructure-lite, development model, which deploys modest amounts of capital to develop a single compound to an early clinical data package which can be partnered with pharma. The asset resides within an LLC, and following the license transaction, the LLC is wound down and distributes the upfront, milestone and royalty payments to the LLC members on a pro rata basis. The key to success in this model is choosing the appropriate asset/indication – one where it is possible to get to a clinical data package on limited capital. This approach excludes many molecules and indications often favored by biotech, and tends to drive towards clinical studies using biomarkers – directly in line with one of pharma’s favored strategies.

This is a much different model, of course, than the "We're going to have an IPO and become our own drug company!" one. But the chances of that happening have been dwindling over the years, and the current funding environment makes it harder than ever, Verastem aside. It's even a rough environment to get acquired in. So licensing is the more common path, and (as this FierceBiotech story says), that's bound to have an effect on the composition of the industry. People aren't holding on to assets for as long as they used to, and they're trying to get by with as little of their own money as they can. Will we end up with a "field of fireflies" model, with dozens, hundreds of tiny companies flickering on and off? What will the business look like after another ten years of this - better, or worse?

Comments (25) + TrackBacks (0) | Category: Business and Markets | Chemical News | Drug Development | Drug Industry History

March 26, 2012

What's the Ugliest Drug? Or The Ugliest Drug Candidate?

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Posted by Derek

I was having one of those "drug-like properties" discussions with colleagues the other day. Admittedly, if you're not in drug discovery yourself, you probably don't have that one very often, but even for us, you'd think that a lot of the issues would be pretty settled by now. Not so.

While everyone broadly agrees that compounds shouldn't be too large or too greasy, where one draws the line is always up for debate. And the arguments gets especially fraught in the earlier stages of a project, when you're still deciding on what chemical series to work on. One point of view (the one I subscribe to) says that almost every time, the medicinal chemistry process is going to make your compound larger and greasier, so you'd better start on the smaller and leaner side to give everyone room to work in. But sometimes, Potency Rules, at least for some people and in some organizations, and there's a lead which might be stretching some definitions but is just too active to ignore. (That way, in my experience, lies heartbreak, but there are people who've made successes out of it).

We've argued these same questions here before, more than once. What I'm wondering today is, what's the least drug-like drug that's made it? It's dangerous to ask that question, in a way, because it gives some people what they see as a free pass to pursue ugly chemical matter - after all, Drug Z made it, so why not this one? (That, to my mind, ignores the ars longa, vita brevis aspect: since there's an extra one-in-a-thousand factor with some compounds, given the long odds already, why would you make them even longer?)

But I think it's still worth asking the question, if we can think of what extenuating circumstances made some of these drugs successful. "Sure, your molecular weight isn't as high as Drug Z, which is on the market, but do you have Drug Z's active transport/distribution profile/PK numbers in mice? If not, just why do you think you're going to be so lucky?"

Antibiotics are surely going to make up some of the top ten candidates - some of those structures are just bizarre. There's a fairly recent oncology drug that I think deserves a mention for its structure, too. Anyone have a weirder example of a marketed drug?

What's still making its way through the clinic can be even stranger-looking. Some of the odder candidates I've seen recently have been for the hepatitis C proteins NS5A and NS5B. Bristol-Myers Squibb has disclosed some eye-openers, such as BMS-790052. (To be fair, that target seems to really like chemical matter like this, and the compound, last I heard, was moving along through the clinic.)

And yesterday, as Carmen Drahl reported from the ACS meeting in San Diego, the company disclosed the structure of BMS-791325, a compound targeting NS5B. That's a pretty big one, too - the series it came from started out reasonably, then became not particularly small, and now seems to have really bulked up, and for the usual reasons - potency and selectivity. But overall, it's a clear example of the sort of "compound bloat" that overtakes projects as they move on.

So, nominations are open for three categories: Ugliest Marketed Drug, Ugliest Current Clinical Candidate, and Ugliest Failed Clinical Candidate. Let's see how bad it gets!

Comments (58) + TrackBacks (0) | Category: Drug Development | Drug Industry History

March 19, 2012

Dealing with the Data

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Posted by Derek

So how do we deal with the piles of data? A reader sent along this question, and it's worth thinking about. Drug research - even the preclinical kind - generates an awful lot of information. The other day, it was pointed out that one of our projects, if you expanded everything out, would be displayed on a spreadsheet with compounds running down the left, and over two hundred columns stretching across the page. Not all of those are populated for every compound, by any means, especially the newer ones. But compounds that stay in the screening collection tend to accumulate a lot of data with time, and there are hundreds of thousands (or millions) of compounds in a good-sized screening collection. How do we keep track of it all?

Most larger companies have some sort of proprietary software for the job (or jobs). The idea is that you can enter a structure (or substructure) of a compound and find out the project it was made for, every assay that's been run on it, all its spectral data and physical properties (experimental and calculated), every batch that's been made or bought (and from whom and from where, with notebook and catalog references), and the bar code of every vial or bottle of it that's running around the labs. You obviously don't want all of those every time, so you need to be able to define your queries over a wide range, setting a few common ones as defaults and customizing them for individual projects while they're running.

Displaying all this data isn't trivial, either. The good old fashioned spreadsheet is perfectly useful, but you're going to need the ability to plot and chart in all sorts of ways to actually see what's going on in a big project. How does human microsomal stability relate to the logP of the right-hand side chain in the pyrimidinyl-series compounds with molecular weight under 425? And how do those numbers compare to the dog microsomes? And how do either of those compare to the blood levels in the whole animal, keeping in mind that you've been using two different dosing vehicles along the way? To visualize these kinds of questions - perfectly reasonable ones, let me tell you - you'll need all the help you can get.

You run into the problem of any large, multifunctional program, though: if it can do everything, it may not do any one thing very well. Or there may be a way to do whatever you want, if only you can memorize the magic spell that will make it happen. If it's one of those programs that you have to use constantly or run the risk of totally forgetting how it goes, there will be trouble.

So what's been the experience out there? In-house home-built software? Adaptations of commercial packages? How does a smaller company afford to do what it needs to do? Comments welcome. . .

Comments (66) + TrackBacks (0) | Category: Drug Assays | Drug Development | Life in the Drug Labs

March 16, 2012

Merck's CALIBR Venture

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Posted by Derek

So the news is that Merck is now going to start its own nonprofit drug research institute in San Diego: CALIBR, the California Institute for Biomedical Research. It'll be run by Peter Schultz of Scripps, and they're planning to hire about 150 scientists (which is good news, anyway, since the biomedical employment picture out in the San Diego area has been grim).

Unlike the Centers for Therapeutic Innovation that Pfizer, a pharmaceutical company based in New York, has established in collaboration with specific academic medical centres around the country, Calibr will not be associated with any particular institution. (Schultz, however, will remain at Scripps.) Instead, academics from around the world can submit research proposals, which will then be reviewed by a scientific advisory board, says Kim. The institute itself will be overseen by a board of directors that includes venture capitalists. Calibr will not have a specific therapeutic focus.

Merck, meanwhile, will have the option of an exclusive licence on any proteins or small-molecule therapeutics to emerge. . .

They're putting up $90 million over the next 7 years, which isn't a huge amount. It's not clear if they have any other sources of funding - they say that they'll "access" such, but I have to wonder, since that would presumably complicate the IP for Merck. It's also not clear what they'll be working on out there; the press release is, well, a press release. The general thrust is translational research, a roomy category, and they'll be taking proposals from academic labs who would like to use their facilities and expertise.

So is this mainly a way for Merck to do more academic collaborations without the possible complications (for universities) of dealing directly with a drug company? Will it preferentially take on high-risk, high-reward projects? There's too little to go on yet. Worth watching with interest as it gets going - and if any readers find themselves interviewing there, please report back!

Comments (47) + TrackBacks (0) | Category: Academia (vs. Industry) | Business and Markets | Drug Development

March 15, 2012

Not Quite So Accelerated, Says PhRMA

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Posted by Derek

We've spent a lot of time here talking about provisional approval of drugs, most specifically Avastin (when its approval for metastatic breast cancer was pulled). But the idea isn't to put drugs on the market that have to be taken back; it's to get them out more quickly in case they actually work.

There's legislation (the TREAT Act) that is attempting to extend the range of provisional approvals. But according to this column by Avik Roy, an earlier version of the bill went much further: it would have authorized new approval pathways for the first drugs to treat specific subpopulations of an existing disease, nonresponders to existing therapies, compounds with demonstrable improvements in safety or efficacy, or (in general) compounds that "otherwise satisfy an unmet medical need". As with the existing accelerated approval process, drugs under these categories could (after negotiation with the FDA) be provisionally marketed after Phase II results, if those were convincing enough, with possible revocation after Phase III results came in.

Unlike the various proposals to put compounds on the market after Phase I (which I fear would be an invitation to game the system), this one strikes me as aggressive but sensible. It would, ideally, encourage companies to run more robust Phase II trials in the hopes of going straight to the market, and it would allow really outstanding drugs a chance to start earning back their R&D costs much earlier. As long as everyone understood that Phase III trials are no slam dunk any more (if they ever were), and that some of these drugs would turn out not to be as good as they looked, I think that on balance, everyone would come out ahead.

According to Roy, this version of the bill had (as you'd expect) attracted strong backers and strong opponents. On the "pro" side was BIO, the biotech industry group, which is no surprise. On the "anti" side, the FDA itself wasn't ready for this big a change, which isn't much of a shock, either. (To be fair to them, this would increase their workload substantially - you'd really want to couple a reform like this with more people on their end). And there were advocacy groups that worried that this new regulatory regime would water down drug safety requirements too much. The article doesn't name any groups, but anyone who's observed the industry can fill in some likely names.

But there was another big group opposing the change: PhRMA. Yes, the trade organization for the large drug companies. Opinions vary as to the reason. The official explanations are that they, too, were concerned for patient safety, and they wanted the PDUFA legislation renewed as is, without these extra provisions (a "bird in the hand" argument). But Roy's piece advances a less charitable thesis:

Sen. Hagan’s proposal would have been devastating to the big pharma R&D oligopoly. If small biotech companies could get their drugs tentatively approved after inexpensive phase II studies, they would have far less need to partner those drugs with big pharma. They could keep the upside themselves and attract far more interest from investors. Big pharma, on the other hand, would be without its largest source for innovative new medicines: the small biotech farm team.

I'd like to be able to doubt this reasoning more than I do. . .

Comments (19) + TrackBacks (0) | Category: Drug Development | Regulatory Affairs

March 14, 2012

The Blackian Demon of Drug Discovery

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Posted by Derek

There's an on-line appendix to that Nature Reviews Drug Discovery article that I've been writing about, and I don't think that many people have read it yet. Jack Scannell, one of the authors, sent along a note about it, and he's interested to see what the readership here makes of it.

It gets to the point that came up in the comments to this post, about the order that you do your screening assays in (see #55 and #56). Do you run everything through a binding assay first, or do you run things through a phenotypic assay first and then try to figure out how they bind? More generally, with either sort of assay, is it better to do a large random screen first off, or is it better to do iterative rounds of SAR from a smaller data set? (I'm distinguishing those two because phenotypic assays provide very different sorts of data density than do focused binding assays).

Statistically, there's actually a pretty big difference there. I'll quote from the appendix:

Imagine that you know all of the 600,000 or so words in the English language and that you are asked to guess an English word written in a sealed envelope. You are offered two search strategies. The first is the familiar ‘20 questions’ game. You can ask a series of questions. You are provided with a "yes" or "no" answer to each, and you win if you guess the word in the envelope having asked 20 questions or fewer. The second strategy is a brute force method. You get 20,000 guesses, but you only get a "yes" or "no" once you have made all 20,000 guesses. So which is more likely to succeed, 20 questions or 20,000 guesses?

A skilled player should usually succeed with 20 questions (since 600,000 is less than than 2^20) but would fail nearly 97% of the time with "only" 20,000 guesses.

Our view is that the old iterative method of drug discovery was more like 20 questions, while HTS of a static compound library is more like 20,000 guesses. With the iterative approach, the characteristics of each molecule could be measured on several dimensions (for example, potency, toxicity, ADME). This led to multidimensional structure–activity relationships, which in turn meant that each new generation of candidates tended to be better than the previous generation. In conventional HTS, on the other hand, search is focused on a small and pre-defined part of chemical space, with potency alone as the dominant factor for molecular selection.

Aha, you say, but the game of twenty questions is equivalent to running perfect experiments each time: "Is the word a noun? Does it have more than five letters?" and so on. Each question carves up the 600,000 word set flawlessly and iteratively, and you never have to backtrack. Good experimental design aspires to that, but it's a hard standard to reach. Too often, we get answers that would correspond to "Well, it can be used like a noun on Tuesdays, but if it's more than five letters, then that switches to Wednesday, unless it starts with a vowel".

The authors try to address this multi-dimensionality with a thought experiment. Imagine chemical SAR space - huge number of points, large number of parameters needed to describe each point.

Imagine we have two search strategies to find the single best molecule in this space. One is a brute force search, which assays a molecule and then simply steps to the next molecule, and so exhaustively searches the entire space. We call this "super-HTS". The other, which we call the “Blackian demon” (in reference to the “Darwinian demon”, which is used sometimes to reflect ideal performance in evolutionary thought experiments, and in tribute to James Black, often acknowledged as one of the most successful drug discoverers), is equivalent to an omniscient drug designer who can assay a molecule, and then make a single chemical modification to step it one position through chemical space, and who can then assay the new molecule, modify it again, and so on. The Blackian demon can make only one step at a time, to a nearest neighbour molecule, but it always steps in the right direction; towards the best molecule in the space. . .

The number of steps for the Blackian demon follows from simple geometry. If you have a d dimensional space with n nodes in the space, and – for simplicity – these are arranged in a neat line, square, cube, or hypercube, you can traverse the entire space, from corner to corner with d x (n^(1/d)-1) steps. This is because each vertex is n nodes in length, and there are d vertices. . .When the search space is high dimensional (as is chemical space) and there is a very large number of nodes (as is the case for drug-like molecules), the Blackian demon is many orders of magnitude more efficient than super-HTS. For example, in a 10 dimensional space with 10^40 molecules, the Blackian demon can search the entire space in 10^5 steps (or less), while the brute force method requires 10^40 steps.

These are idealized cases, needless to say. One problem is that none of us are exactly Blackian demons - what if you don't always make the right step to the next molecule? What if your iteration only gives one out of ten molecules that get better, or one out of a hundred? I'd be interested to see how that affects the mathematical argument.

And there's another conceptual problem: for many points in chemical space, the numbers are even much more sparse. One assumption with this thought experiment (correct me if I'm wrong) is that there actually is a better node to move to each time. But for any drug target, there are huge regions of flat, dead, inactive, un-assayable chemical space. If you started off in one of those, you could iterate until your hair fell out and never get out of the hole. And that leads to another objection to the ground rules of this exercise: no one tries to optimize by random HTS. It's only used to get starting points for medicinal chemists to work on, to make sure that they're not starting in one of those "dead zones". Thoughts?

Comments (45) + TrackBacks (0) | Category: Drug Assays | Drug Development | Drug Industry History

March 12, 2012

The Brute Force Bias

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Posted by Derek

I wanted to return to that Nature Reviews Drug Discovery article I blogged about the other day. There's one reason the authors advance for our problems that I thought was particularly well stated: what they call the "basic research/brute force" bias.

The ‘basic research–brute force’ bias is the tendency to overestimate the ability of advances in basic research (particularly in molecular biology) and brute force screening methods (embodied in the first few steps of the standard discovery and preclinical research process) to increase the probability that a molecule will be safe and effective in clinical trials. We suspect that this has been the intellectual basis for a move away from older and perhaps more productive methods for identifying drug candidates. . .

I think that this is definitely a problem, and it's a habit of thinking that almost everyone in the drug research business has, to some extent. The evidence that there's something lacking has been piling up. As the authors say, given all the advances over the past thirty years or so, we really should have seen more of an effect in the signal/noise of clinical trials: we should have had higher success rates in Phase II and Phase III as we understood more about what was going on. But that hasn't happened.

So how can some parts of a process improve dramatically, yet important measures of overall performance remain flat or decline? There are several possible explanations, but it seems reasonable to wonder whether companies industrialized the wrong set of activities. At first sight, R&D was more efficient several decades ago , when many research activities that are today regarded as critical (for example, the derivation of genomics-based drug targets and HTS) had not been invented, and when other activities (for example, clinical science, animal-based screens and iterative medicinal chemistry) dominated.

This gets us back to a topic that's come up around here several times: whether the entire target-based molecular-biology-driven style of drug discovery (which has been the norm since roughly the early 1980s) has been a dead end. Personally, I tend to think of it in terms of hubris and nemesis. We convinced ourselves that were were smarter than we really were.

The NRDD piece has several reasons for this development, which also ring true. Even in the 1980s, there were fears that the pace of drug discovery was slowing. and a new approach was welcome. A second reason is a really huge one: biology itself has been on a reductionist binge for a long time now. And why not? The entire idea of molecular biology has been incredibly fruitful. But we may be asking more of it than it can deliver.

. . .the ‘basic research–brute force’ bias matched the scientific zeitgeist, particularly as the older approaches for early-stage drug R&D seemed to be yielding less. What might be called 'molecular reductionism' has become the dominant stream in biology in general, and not just in the drug industry. "Since the 1970s, nearly all avenues of biomedical research have led to the gene". Genetics and molecular biology are seen as providing the 'best' and most fundamental ways of understanding biological systems, and subsequently intervening in them. The intellectual challenges of reductionism and its necessary synthesis (the '-omics') appear to be more attractive to many biomedical scientists than the messy empiricism of the older approaches.

And a final reason for this mode of research taking over - and it's another big one - is that it matched the worldview of many managers and investors. This all looked like putting R&D on a more scientific, more industrial, and more manageable footing. Why wouldn't managers be attracted to something that looked like it valued their skills? And why wouldn't investors be attracted to something that looked as if it could deliver more predictable success and more consistent earnings? R&D will give you gray hairs; anything that looks like taming it will find an audience.

And that's how we find ourselves here:

. . .much of the pharmaceutical industry's R&D is now based on the idea that high-affinity binding to a single biological target linked to a diseases will lead to medical benefit in humans. However, if the causal link between single targets and disease states is weaker than commonly thought, or if drugs rarely act on a single target, one can understand why the molecules that have been delivered by this research strategy into clinical development may not necessarily be more likely to succeed than those in earlier periods.

That first sentence is a bit terrifying. You read it, and part of you thinks "Well, yeah, of course", because that is such a fundamental assumption of almost all our work. But what if it's wrong? Or just not right enough?

Comments (64) + TrackBacks (0) | Category: Drug Development | Drug Industry History

March 6, 2012

Drug Discovery for Physicists

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Posted by Derek

There's a good post over at the Curious Wavefunction on the differences between drug discovery and the more rigorous sciences. I particularly liked this line:

The goal of many physicists was, and still is, to find three laws that account for at least 99% of the universe. But the situation in drug discovery is more akin to the situation in finance described by the physicist-turned-financial modeler Emanuel Derman; we drug hunters would consider ourselves lucky to find 99 laws that describe 3% of the drug discovery universe.

That's one of the things that you get used to in this field, but when you step back, it's remarkable: so much of what we do remains relentlessly empirical. I don't just mean finding a hit in a screening assay. It goes all the way through the process, and the further you go, the more empirical it gets. Cell assays surprise you compared to enzyme preps, and animals are a totally different thing than cells. Human clinical trials are the ultimate in empirical data-gathering: there's no other way to see if a drug is truly safe (or effective) in humans other than giving it to a whole big group of humans. We do all sorts of assays to avoid getting to that stage, or to feel more confident when we're about to make it there, but there's no substituted for actually doing it.

There's a large point about reductionism to be made, too:

Part of the reason drug discovery can be challenging to physicists is because they are steeped in a culture of reductionism. Reductionism is the great legacy of twentieth-century physics, but while it worked spectacularly well for particle physics it doesn't quite work for drug design. A physicist may see the human body or even a protein-drug system as a complex machine whose understandings we can completely understand once we break it down into its constituent parts. But the chemical and biological systems that drug discoverers deal with are classic examples of emergent phenomena. A network of proteins displays properties that are not obvious from the behavior of the individual proteins. . .Reductionism certainly doesn't work in drug discovery in practice since the systems are so horrendously complicated, but it may not even work in principle.

And there we have one of the big underlying issues that needs to be faced by the hardware engineers, software programmers, and others who come in asking why we can't be as productive as they are. There's not a lot of algorithmic compressibility in this business. Whether they know it or not, many other scientists and engineers are living in worlds where they're used to it being there when they need it. But you won't find much here.

Comments (22) + TrackBacks (0) | Category: Drug Assays | Drug Development

February 22, 2012

Scaling Up a Strange Dinitro Compound (And Others)

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Posted by Derek

I wrote here about a very unusual dinitro compound that's in the clinic in oncology. Now there's a synthetic chemistry follow-up, in the form of a paper in Organic Process R&D.
dinitro.png

It's safe to say that most process and scale-up chemists are never going to have to worry about making a gem-dinitroazetidine - or, for that matter, a gem-dinitroanything. But the issues involved are the same ones that come up over and over again. See if this rings any bells:

Gram quantities of (3) for initial anticancer screening were originally prepared by an unoptimized approach that was not suitable for scale-up and failed to address specific hazards of the reaction intermediates and coproducts. The success of (3) in preclinical studies prompted the need for a safe, reliable, and scalable synthesis to provide larger supplies of the active pharmaceutical ingredient (API) for further investigation and eventual clinical trials.

Yep, it's when you need large, reliable batches of something that the inadequacies of your chemistry really stand out. The kinds of chemistry that people like me do, back in the discovery labs, often has to be junked. It's fine for making 100mg of something to put in the archives - and tell me, when was the last time you put as much as 100 milligrams of a new compound into the archives? But there are usually plenty of weak points as you try to go to gram, then hundreds of grams, then kilos and up. Among them are:

(1) Exothermic chemistry. Excess heat is easy to shed from a 25-mL round-bottom flask. Heat is not so easily lost from larger vessels, though, and the number of chemists who have had to discover this the hard way is beyond counting. The world is very different when everything in the flask is no longer just 1 cm away from a cold glass wall.

(2) Stirring. This can be a pain even on the small scale, so imagine what a headache it is by the kilo. Gooey precipitates, thick milkshake-like reactions, lumps of crud - what's inconvenient when small can turn into a disaster later on, because poor stirring leads to localized heating (see above), incomplete reactions, side products, and more.

(3) Purification. Just run it down a column? Not so fast, chief. Where, exactly, do you find the columns to run kilos of material across? And the pumps to force the stuff through? And the wherewithal to dispose of all that solid-phase stuff once you've turned it all those colors and it can't be used again? And the time and money to evaporate all that solvent that you're using? No, the scale-up people will go a long way to avoid chromatography. Precipitations and crystallizations are the way to go, if at all possible.

Reproducibility. All of these factors influence this part. One of the most important things about a good chemical process is that it works the same flippin' way every single time. As has been said before around here, a route that generates 97% yield most of the time, but with an occasional mysterious 20% flop, is useless. Worse than useless. Squeezing the mystery out of the synthesis is the whole point of process chemistry: you want to know what the side products are, why they form, and how to control every variable.

Oh yeah. Cost.Cost-of-goods is rarely a deal-breaker in drug research, but that's partly because people are paying attention to it. In the med-chem labs, we think nothing of using exotic reagents that the single commercial supplier marks up to the sky. That will not fly on scale. Cutting out three steps with a reagent that isn't obtainable in quantity doesn't help the scale-up people one bit. (The good news is that some of these things turn out to be available when someone really wants them - the free market in action).

There are other factors, but those are some of the main ones. It's a different world, and it involves thinking about things that a discovery chemist just never thinks about. (Does your product tend to create a fine dust on handling? The sort that might fill a room and explode with static electricity sparks? Can your reaction mixture be pumped through a pipe as a slurry, or not? And so on.) It looks as if the dinitro compound has made it through this gauntlet successfully, but every day, there's someone at some drug company worrying about the next candidate.

Comments (19) + TrackBacks (0) | Category: Drug Development | Life in the Drug Labs

February 10, 2012

The Terrifying Cost of a New Drug

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Posted by Derek

Matthew Herper at Forbes has a very interesting column, building on some data from Bernard Munos (whose work on drug development will be familiar to readers of this blog). What he and his colleague Scott DeCarlo have done is conceptually simple: they've gone back over the last 15 years of financial statements from a bunch of major drug companies, and they've looked at how many drugs each company has gotten approved.

Over that long a span, things should even out a bit. There will be some spending which won't show up in the count, that took place on drugs that got approved during the earlier part that span, but (on the back end) there's spending on drugs in there that haven't made it to market yet, too. What do the numbers look like? Hideous. Appalling. Unsustainable.

AstraZeneca, for example, got 5 drugs on the market during this time span, the worst performance on this list, and thus spent spent nearly $12 billion dollars per drug. No wonder they're in the shape they're in. GSK, Sanofi, Roche, and Pfizer all spent in the range of $8 billion per approved drug. Amgen did things the cheapest by this measure, 9 drugs approved at about 3.7 billion per drug.

Now, there are several things to keep in mind about these numbers. First - and I know that I'm going to hear about this from some people - you might assume that different companies are putting different things under the banner of R&D for accounting purposes. But there's a limit to how much of that you can do. Remember, there's a separate sales and marketing budget, too, of course, and people never get tired of pointing out that it's even larger than the R&D one. So how inflated can these figures be? Second, how can these numbers jibe with the 800-million-per-new-drug (recently revised to $1 billion), much less with the $43 million per new drug figure (from Light and Warburton) that was making the rounds a few months ago?

Well, I tried to dispose of that last figure at the time. It's nonsense, and if it were true, people would be lining up to start drug companies (and other people would be throwing money at them to help). Meanwhile, the drug companies that already exist wouldn't be frantically firing thousands of people and selling their lab equipment at auction. Which they are. But what about that other estimate, the Tufts/diMasi one? What's the difference?

As Herper rightly says, the biggest factor is failure. The Tufts estimate is for the costs racked up by one drug making it through. But looking at the whole R&D spend, you can see how money is being spent for all the stuff that doesn't get through. And as I and many of the other readers of this blog can testify, there's an awful lot of it. I'm now in my 23rd year of working in this industry, and nothing I've touched has ever made it to market yet. If someone wins $500 from a dollar slot machine, the proper way to figure the costs is to see how many dollars, total, they had to pump into the thing before they won - not just to figure that they spent $1 to win. (Unless, of course, they just sat down, and in this business we don't exactly have that option).

No, these figures really show you why the drug business is in the shape it's in. Look at those numbers, and look at how much a successful drug brings in, and you can see that these things don't always do a very good job of adding up. That's with the expenses doing nothing but rising, and the success rate for drug discovery going in the other direction, too. No one should be surprised that drug prices are rising under these conditions. The surprise is that there are still people out there trying to discover drugs.

Comments (62) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Drug Prices

January 26, 2012

Putting a Number on Chemical Beauty

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Posted by Derek

There's a new paper out in Nature Chemistry called "Quantifying the Chemical Beauty of Drugs". The authors are proposing a new "desirability score" for chemical structures in drug discovery, one that's an amalgam of physical and structural scores. To their credit, they didn't decide up front which of these things should be the miost important. Rather, they took eight properties over 770 well-known oral drugs, and set about figuring how much to weight each of them. (This was done, for the info-geeks among the crowd, by calculating the Shannon entropy for each possibility to maximize the information contained in the final model). Interestingly, this approach tended to give zero weight to the number of hydrogen-bond acceptors and to the polar surface area, which suggests that those two measurements are already subsumed in the other factors.

And that's all fine, but what does the result give us? Or, more accurately, what does it give us that we haven't had before? After all, there have been a number of such compound-rating schemes proposed before (and the authors, again to their credit, compare their new proposal with the others head-to-head). But I don't see any great advantage. The Lipinski "Rule of 5" is a pretty simple metric - too simple for many tastes - and what this gives you is a Rule of 5 with both categories smeared out towards each other to give some continuous overlap. (See the figure below, which is taken from the paper). That's certainly more in line with the real world, but in that real world, will people be willing to make decisions based on this method, or not?
QED%20paper%20chart%20png.png
The authors go for a bigger splash with the title of the paper, which refers to an experiment they tried. They had chemists across AstraZeneca's organization assess some 17,000 compounds (200 or so for each) with a "Yes/No" answer to "Would you undertake chemistry on this compound if it were a hit?" Only about 30% of the list got a "Yes" vote, and the reasons for rejecting the others were mostly "Too complex", followed closely by "Too simple". (That last one really makes me wonder - doesn't AZ have a big fragment-based drug design effort?) Note also that this sort of experiment has been done before.

Applying their model, the mean score for the "Yes" compounds was 0.67 (s.d.0.16), and the mean score for the "No" compounds was 0.49 (s.d. 0.23, which they say was statistically significant, although that must have been a close call. Overall, I wouldn't say that this test has an especially strong correlation with medicinal chemists' ideas of structural attractiveness, but then, I'm not so sure of the usefulness of those ideas to start with. I think that the two ends of the scale are hard to argue with, but there's a great mass of compounds in the middle that people decide that they like or don't like, without being able to back up those statements with much data. (I'm as guilty as anyone here).

The last part of the paper tries to extend the model from hit compounds to the targets that they bind to - a druggability assessment. The authors looked through the ChEMBL database, and ranked the various target by the scores of the ligands that are associated with them. They found that their mean ligand score for all the targets in there is 0.478. For the targets of approved drugs, it's 0.492, and for the orally active ones it's 0.539 - so there seems to be a trend, although if those differences reached statistical significance, it isn't stated in the paper.

So overall, I find nothing really wrong with this paper, but nothing spectacularly right with it, either. I'd be interested in hearing other calls on it as it gets out into the community. . .

Comments (22) + TrackBacks (0) | Category: Drug Development | Drug Industry History | In Silico | Life in the Drug Labs

January 18, 2012

Fun With Epigenetics

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Posted by Derek

If you've been looking around the literature over the last couple of years, you'll have seen an awful lot of excitement about epigenetic mechanisms. (Here's a whole book on that very subject, for the hard core). Just do a Google search with "epigenetic" and "drug discovery" in it, any combination you like, and then stand back. Articles, reviews, conferences, vendors, journals, startups - it's all there.

Epigenetics refers to the various paths - and there are a bunch of them - to modify gene expression downstream of just the plain ol' DNA sequence. A lot of these are, as you'd imagine, involved in the way that the DNA itself is wound (and unwound) for expression. So you see enzymes that add and remove various switches to the outside of various histone proteins. You have histone acyltransferases (HATs) and histone deacetylases (HDACs), methyltransferases and demethylases, and so on. Then there are bromodomains (the binding sites for those acetylated histones) and several other mechanisms, all of which add up to plenty o' drug targets.

Or do they? There are HDAC compounds out there in oncology, to be sure, and oncology is where a lot of these other mechanisms are being looked at most intensively. You've got a good chance of finding aberrant protein expression levels in cancer cells, you have a lot of unmet medical need, a lot of potential different patient populations, and a greater tolerance for side effects. All of that argues for cancer as a proving ground, although it's certainly not the last word. But in any therapeutic area, people are going to have to wrestle with a lot of other issues.

Just looking over the literature can make you both enthusiastic and wary. There's an awful lot of regulatory machinery in this area, and it's for sure that it isn't there for jollies. (You'd imagine that selection pressure would operate pretty ruthlessly at the level of gene expression). And there are, of course, an awful lot of different genes whose expression has to be regulated, at different levels, in different cell types, at different phases of their development, and in response to different environmental signals. We don't understand a whole heck of a lot of the details.

So I think that there will be epigenetic drugs coming out of this burst of effort, but I don't think that they're going to exactly be the most rationally designed things we've ever seen. That's fine - we'll take drug candidates where we can get them. But as for when we're actually going to understand all these gene regulation pathways, well. . .

Comments (15) + TrackBacks (0) | Category: Biological News | Cancer | Drug Development

January 16, 2012

Biogen: A "Decimated" Pipeline?

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Posted by Derek

You don't want coverage like this: "Biogen CEO Tries to Refill Early-Stage Pipeline He Decimated". That would be George Scanos:

. . .Scangos and his research chief eliminated about 17 early-stage drug projects in 2010 and last year to hone the company's focus, leaving it with only about four early-stage compounds. Biogen exited oncology and cardiovascular research and is now targeting drugs to treat neurological and autoimmune conditions. . .

"We didn't want to fund projects that were unlikely to generate value," Scangos said in an interview on the sidelines of the J.P. Morgan health-care conference in San Francisco this week. . .But even if Biogen's late-stage pipeline delivers successful new drugs soon, the company needs more compounds in early-stage testing to sustain long-term growth. So it is licensing drugs from other companies. . .

The article itself (from Peter Loftus, originally in the Wall Street Journal isn't quite as harsh as the headline. As as that excerpt shows, part of the problem is that Scanos thought that the company was in some therapeutic areas that they shouldn't have been in at all, so that pipeline he's refilling isn't exactly the same one he cleared out. (And a note to the WSJ headline writers: "decimated" isn't a synonym for "got rid of a lot", although that horse, I fear, left the barn a long time ago. The mental image of decimating a pipeline isn't the sharpest vision ever conjured up by a headline, either, but I understand that these things are done on deadline.)

No, if I had to pick the biggest expensive reversal done under Biogen's new management, I'd pick the construction site a few blocks from here where they're putting up the company's new Cambridge headquarters. Those are the offices that used to be in. . .well, Cambridge, until former CEO Jim Mullen moved them out to Weston just a couple of years ago. I don't know how long it's going to take them to finish those buildings (right now, they're just past the bare-ground stage), but maybe eventually they can all work there for a few months before someone else decides to move them to Northhampton, Nashua, or Novosibirsk.

Comments (20) + TrackBacks (0) | Category: Drug Development

January 12, 2012

Welcome To the Jungle! Here's Your Panther.

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Posted by Derek

English has no word of its own for schadenfreude, so we've had to appropriate the German one, and we're in the process of making it our own - just as we did with "kindergarten", not to mention "ketchup" and "pyjamas", among fifty zillion more. That's because the emotion is not peculiar to German culture, oh no. We can feel shameful joy at others' discomfort with the best of them - like, for example, when people start to discover from experience just how hard drug discovery really is.

John LaMattina has an example over at Drug Truths. Noting the end of a research partnership between Eli Lilly and the Indian company Zydus Cadila, he picked up on this language:

“Developing a new drug from scratch is getting more expensive due to increased regulatory scrutiny and high costs of clinical trials. Lowering costs through a partnership with an Indian drug firm was one way of speeding up the process, but the success rate has not been very high.”

And that, as he correctly notes, is no slam on the Indian companies involved, just as it won't be one on the Chinese companies when they run into the same less-than-expected returns. No, the success rate has not been very high anywhere. Going to India and China might cut your costs a bit (although that window is slowly closing as we watch), but for early-stage research, the costs are not the important factor.

Everything we do in preclinical is a roundoff error compared to a big Phase III trial, as far as direct costs go. What we early-stage types specialize in, God help us, are opportunity costs, and those don't get reported on the quarterly earnings statements. There's no GAAP way to handle the cost of going for the wrong series of lead compounds on the way to the clinic, starting a program on the wrong target entirely, or not starting one instead on something that would have actually panned out. These are the big decisions in early stage research, and they're all judgment calls based on knowledge that is always incomplete. You will not find the answers to the questions just by going to Shanghai or Bangalore. The absolute best you can hope for is to spend a bit less money while searching for them, and thus shave some dollars off what is the smallest part of your R&D budget to start with. Sound like a good deal?

Relative to the other deals on offer, it might just be worthwhile. Such is the state of things, and such are the savings that people are willing to reach for. But when you're in the part of drug discovery that depends on feeling your way into unknown territory - the crucial part - you shouldn't expect any bargains.

Comments (18) + TrackBacks (0) | Category: Business and Markets | Drug Development

January 6, 2012

Do We Believe These Things, Or Not?

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Posted by Derek

Some of the discussions that come up here around clinical attrition rates and compound properties prompts me to see how much we can agree on. So, are these propositions controversial, or not?

1. Too many drugs fail in clinical trials. We are having a great deal of trouble going on with these failure rates, given the expense involved.

2. A significant number of these failures are due to lack of efficacy - either none at all, or not enough.

2a. Fixing efficacy failures is hard, since it seems to require deeper knowledge, case-by-case, of disease mechanisms. As it stands, we get a significant amount of this knowledge from our drug failures themselves.

2b. Better target selection without such detailed knowledge is hard to come by. Good phenotypic assays are perhaps the only shortcut, but a good phenotypic assays are not easy to develop and validate.

3. Outside of efficacy, a significant number of clinical failures are also due to side effects/toxicity. These two factors (efficacy and tox) account for the great majority of compounds that drop out of the clinic.

3a. Fixing tox/side effect failures through detailed knowledge is perhaps hardest of all, since there are a huge number of possible mechanisms. There are far more ways for things to go wrong than there are for them to work correctly.

3b. But there are broad correlations between molecular structures and properties and the likelihood of toxicity. While not infallible, these correlations are strong enough to be useful, and we should be grateful for anything we can get that might diminish the possibility of later failure.

Example of such structural features are redox-active groups like nitros and quinones, which really are associated with trouble - not invariably, but enough to make you very cautious. More broadly, high logP values are also associated with trouble in development - not as strongly, but strong enough to be worth considering.

So, is everyone pretty much in agreement with these things? What I'm saying is that if you take a hundred aryl nitro compounds into development, versus a hundred that don't have such a group, the latter cohort of compounds will surely have a higher success rate. And if you take a hundred compounds with logP values of 1 to 3 into development, these will have a higher success rate than a hundred compounds, against the same targets, with logP of 4 to 6. Do we believe this, or not?

Comments (34) + TrackBacks (0) | Category: Drug Assays | Drug Development | Toxicology

January 5, 2012

Lead-Oriented Synthesis - What Might That Be?

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Posted by Derek

A new paper in Angewandte Chemie tries to open another front in relations between academic and drug industry chemists. It's from several authors at GSK-Stevenage, and it proposes something they're calling "Lead-Oriented Synthesis". So what's that?

Well, the paper itself starts out as a quick tutorial on the state and practice of medicinal chemistry. That's a good plan, since Angewandte Chemie is not primarily a med-chem journal (he said with a straight face). Actually, it has the opposite reputation, a forum where high-end academic chemistry gets showplaced. So the authors start off by reminded the readership what drug discovery entails. And although we've had plenty of discussions around here about these topics, I think that most people can agree on the main points laid out:

1. Physical properties influence a drug's behavior.
2. Among those properties, logP may well be the most important single descriptor,
3. Most successful drugs have logP values between 1 and perhaps 4 or 5. Pushing the lipophilicity end of things is, generally speaking, asking for trouble.
4. Since optimization of lead compounds almost always adds molecular weight, and very frequently adds lipophilicity, lead compounds are better found in (and past) the low ends of these property ranges, to reduce the risk of making an unwieldy final compound.

As the authors take pains to say, though, there are many successful drugs that fall outside these ranges. But many of those turn out to have some special features - antibacterial compounds (for example) tend to be more polar outliers, for reasons that are still being debated. There is, though, no similar class of successful less polar than usual drugs, to my knowledge. If you're starting a program against a target that you have no reason to think is an outlier, and assuming you want an oral drug for it, then your chances for success do seem to be higher within the known property ranges.

So, overall, the GSK folks maintain that lead compounds for drug discovery are most desirable with logP values between -1 and 3, molecular weights from around 200 to 350, and no problematic functional groups (redox-active and so on). And I have to agree; given the choice, that's where I'd like to start, too. So why are they telling all this to the readers of Angewandte Chemie? Because these aren't the sorts of compounds that academic chemists are interested in making.

For example, a survey of the 2009 issues of the Journal of Organic Chemistry found about 32,700 compounds indexed with the word "preparation" in Chemical Abstracts, after organometallics, isotopically labeled compounds, and commercially available ones were stripped out. 60% of those are outside the molecular weight criteria for lead-like compounds. Over half the remainder fail cLogP, and most of the remaining ones fail the internal GSK structural filters for problematic functional groups. Overall, only about 2% of the JOC compounds from that year would be called "lead-like". A similar analysis across seven other synthetic organic journals led to almost the same results.

Looking at array/library synthesis, as reported in the Journal of Combinatorial Chemistry and from inside GSK's own labs, the authors quantify something else that most chemists suspected: the more polar structures tend to drop out as the work goes on. This "cLogP drift" seems to be due to incompatible chemistries or difficulties in isolation and purification, and this could also illustrate why many new synthetic methods aren't applied in lead-like chemical space: they don't work as well there.

So that's what underlies the call for "lead-oriented synthesis". This paper is asking for the development of robust reactions which will work across a variety of structural types, will be tolerant of polar functionalities, and will generate compounds without such potentially problematic groups as Michael acceptors, nitros, and the like. That's not so easy, when you actually try to do it, and the hope is that it's enough of a challenge to attract people who are trying to develop new chemistry.

Just getting a high-profile paper of this sort out into the literature could help, because it's something to reference in (say) grant applications, to show that the proposed research is really filling a need. Academic chemists tend, broadly, to work on what will advance or maintain their positions and careers, and if coming up with new reactions of this kind can be seen as doing that, then people will step up and try it. And the converse applies, too, and how: if there's no perceived need for it, no one will bother. That's especially true when you're talking about making molecules that are smaller than the usual big-and-complex synthetic targets, and made via harder-than-it-looks chemistry.

Thoughts from the industrial end of things? I'd be happy to see more work like this being done, although I think it' going to take more than one paper like this to get it going. That said, the intersection with popular fragment-based drug design ideas, which are already having an effect in the purely academic world of diversity-oriented synthesis, might give an extra impetus to all this.

Comments (34) + TrackBacks (0) | Category: Chemical News | Drug Assays | Drug Development | The Scientific Literature

December 22, 2011

More From Hua - A Change of Business Plans?

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Posted by Derek

You may remember the mention of Hua Pharmaceuticals here back in August, and the follow-up with details from the company. They're trying to in-license drugs from other companies and get them approved as quickly as possible in China. The original C&E News article made them sound wildly ambitious, while the company's own information just made them sound very ambitious.

Now we have some more information: Roche has licensed their glucokinase activator program (for diabetes) to Hua (that's a development effort I wrote about here). And that's an interesting development, because the Hua folks told me that:

"Hua Medicine intends to in-license patented drugs from the US and EU, and get them on the market and commercialized in the 4 year timeframe in China. This is about the average time it takes imported drugs (drugs that are approved and marketed in the US or EU but are coming newly into the Chinese market) to get approved by the SFDA in China."

And that's fine, but Roche's glucokinase activators haven't been approved or marketed anywhere yet. In fact, I'm not at all sure of the lead compound ever even made it to Phase III, so there's a lot of expensive work to be done yet, and on a groundbreaking mechanism, too. The only thing I can say is that approval in the US for diabetes drugs has gotten a lot harder over the years - the market is pretty well-served, for one thing, and the safety requirements (particularly cardiovascular) have gotten much more stringent. Perhaps these concerns are not so pressing in China, leading to an easier development path?

Easier or not, these compounds have a lot of time and money left to be put into them, which is not the sort of program that Hua seemed to be targeting before. One wonders if there just weren't any safer bets available. At any rate, good luck to them, and to their financial backers. Some will be needed; it always is.

Comments (8) + TrackBacks (0) | Category: Business and Markets | Diabetes and Obesity | Drug Development

December 13, 2011

The Sirtuin Saga

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Posted by Derek

Science has a long article detailing the problems that have developed over the last few years in the whole siturin story. That's a process that I've been following here as well (scrolling through this category archive will give you the tale), but this is a different, more personality-driven take. The mess is big enough to warrant a long look, that 's for sure:

". . .The result is mass confusion over who's right and who's wrong, and a high-stakes effort to protect reputations, research money, and one of the premier theories in the biology of aging. It's also a story of science gone sour: Several principals have dug in their heels, declined to communicate, and bitterly derided one another. . ."

As the article shows, one of the problems is that many of the players in this drama came out of the same lab (Leonard Guarente's at MIT), so there are issues even beyond the usual ones. Mentioned near the end of the article is the part of the story that I've spent more time on here, the founding of Sirtris and its acquisition by GlaxoSmithKline. It's safe to say that the jury is still out on that one - from all that anyone can tell from outside, it could still work out as a big diabetes/metabolism/oncology success story, or it could turn out to have been a costly (and arguably preventable) mistake. There are a lot of very strongly held opinions on both sides.

Overall, since I've been following this field from the beginning, I find the whole thing a good example of how tough it is to make real progress in fundamental biology. Here you have something that is (or at the very least has appeared to be) very interesting and important, studied by some very hard-working and intelligent people all over the world for years now, with expenditure of huge amounts of time, effort, and money. And just look at it. The questions of what sirtuins do, how they do it, and whether they can be the basis of therapies for human disease - and which diseases - are all still the subject of heated argument. Layers upon layers of difficulty and complexity get peeled back, but the onion looks to be as big as it ever was.

I'm going to relate this to my post the other day about the engineer's approach to biology. This sort of tangle, which differs only in degree and not in kind from many others in the field, illustrates better than anything else how far away we are from formalism. Find some people who are eager to apply modern engineering techniques to medical research, and ask them to take a crack at the sirtuins. Or the nuclear receptors. Or autoimmune disease, or schizophrenia therapies. Turn 'em loose on one of those problems, come back in a year, and see what color their remaining hair is.

Comments (9) + TrackBacks (0) | Category: Aging and Lifespan | Drug Development | Drug Industry History

December 9, 2011

Drugs, Airplanes, and Radios

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Posted by Derek

Wavefunction has a good post in response to this article, which speculates "If we designed airplanes the way we design drugs. . ." I think the original article is worth reading, but some - perhaps many - of its points are arguable. For example:

Every drug that fails in a clinical trial or after it reaches the market due to some adverse effect was “bad” from the day it was first drawn by the chemist. State-of-the-art in silico structure–property prediction tools are not yet able to predict every possible toxicity for new molecular structures, but they are able to predict many of them with good enough accuracy to eliminate many poor molecules prior to synthesis. This process can be done on large chemical libraries in very little time. Why would anyone design, synthesize, and test molecules that are clearly problematic, when so many others are available that can also hit the target? It would be like aerospace companies making and testing every possible rocket motor design rather than running the simulations that would have told them ahead of time that disaster or failure to meet performance specifications was inevitable for most of them.

This particular argument mixes up several important points which should remain separate. Would these simulations have predicted those adverse-effect failures the author mentions? Can they do so now, ex post facto? That would be a very useful piece of information, but in its absence I can't help but wonder if the tools he's talking about would have cheerfully passed Vioxx, or torcetrapib, or the other big failures of recent years. Another question to ask is how many currently successful drugs these tox simulations would have killed off - any numbers there?

The whole essay recalls Lazebnik's famous paper "Can A Biologist Fix A Radio?" (PDF). This is an excellent place to start if you want to explore what I've called the Andy Grove Fallacy. Lazebnik's not having any of the reasons I give for it being a fallacy - for example:

A related argument is that engineering approaches are not applicable to cells because these little wonders are fundamentally different from objects studied by engineers. What is so special about cells is not usually specified, but it is implied that real biologists feel the difference. I consider this argument as a sign of what I call the urea syndrome because of the shock that the scientific community had two hundred years ago after learning that urea can be synthesized by a chemist from inorganic materials. It was assumed that organic chemicals could only be produced by a vital force present in living organisms. Perhaps, when we describe signal transduction pathways properly, we would realize that their similarity to the radio is not superficial. . .

That paper goes on to call for biology to come up with some sort of formal language and notation to describe biochemical systems, something that would facilitate learning and discovery in the same way as circuit diagrams and the like. And that's a really interesting proposal on several levels: would that help? Is it even possible? If so, where to even start? Engineers, like the two authors of the papers I've quoted from, tend to answer "Yes", "Certainly", and "Start anywhere, because it's got to be more useful than what you people have to work with now". But I'm still not convinced.

I've talked about my reasons for this before, but let me add another one: algorithmic complexity. Fields more closely based on physics can take advantage of what's been called "the unreasonable effectiveness" of mathematics. And mathematics, and the principles of physics that can be stated in that form, give an amazingly compact and efficient description of the physical world. Maxwell's equations are a perfect example: there's classical electromagnetism for you, wrapped up into a beautiful little sculpture.

But biological systems are harder to reduce - much harder. There are so many nonlinear effects, so many crazy little things that can add up to so much more than you'd ever think. Here's an example - I've been writing about this problem for years now. It's very hard to imagine compressing these things into a formalism, at least not one that would be useful enough to save anyone time or effort.

That doesn't mean it isn't worth trying. Just the fact that I have trouble picturing something doesn't mean it can't exist, that's for sure. And I'd definitely like to be wrong about this one. But where to begin?

Comments (36) + TrackBacks (0) | Category: Drug Development | Drug Industry History

December 6, 2011

Riding to the Rescue of Rhodanines

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Posted by Derek

There's a new paper coming to the defense of rhodanines, a class of compound that has been described as "polluting the scientific literature". Industrial drug discovery people tend to look down on them, but they show up a lot, for sure.

This new paper starts off sounding like a call to arms for rhodanine fans, but when you actually read it, I don't think that there's much grounds for disagreement. (That's a phenomenon that's worth writing about sometime by itself - the disconnects between title/abstract and actual body text that occur in the scientific literature). As I see it, the people with a low opinion of rhodanines are saying "Look out! These things hit in a lot of assays, and they're very hard to develop into drugs!". And this paper, when you read the whole thing, is saying something like "Don't throw away all the rhodanines yet! They hit a lot of things, but once in a while one of them can be developed into a drug!" The argument is between people who say that elephants are big and people who say that they have trunks.

The authors prepared a good-sized assortment of rhodanines and similar heterocycles (thiohydantoins, hydantoins, thiazolidinediones) and assayed them across several enzymes. Only the ones with double-bonded sulfur (rhodanines and thiohydantoins) showed a lot of cross-enzyme potency - that group has rather unusual electronic properties, which could be a lot of the story. Here's the conclusion, which is what makes me think that we're all talking about the same thing:

We therefore think that rhodanines and related scaffolds should not be regarded as problematic or promiscuous binders per se. However, it is important to note that the intermolecular interaction profile of these scaffolds makes them prone to bind to a large number of targets with weak or moderate affinity. It may be that the observed moderate affinities of rhodanines and related compounds, e.g. in screening campaigns, has been overinterpreted in the past, and that these compounds have too easily been put forward as lead compounds for further development. We suggest that particularly strong requirements, i.e. affinity in the lower nanomolar range and proven selectivity for the target, are applied in the further assessment of rhodanines and related compounds. A generalized "condemnation" of these chemotypes, however, appears inadequate and would deprive medicinal chemists from attractive building blocks that possess a remarkably high density of intermolecular interaction points.

That's it, right there: the tendency to bind off-target, as noted by these authors, is one of the main reasons that these compounds are regarded with suspicion in the drug industry. We know that we can't test for everything, so when you have one of these structures, you're always fearful of what else it can do once it gets into an animal (or a human). Those downstream factors - stability, pharmacokinetics, toxicity - aren't even addressed in this paper, which is all about screening hits. And that's another source of the bad reputation, for industry people: too many times, people who aren't so worried about those qualities have screening commercial compound collections, come up with rhodanines, and published them as potential drug leads, when (as this paper illustrates), you have to be careful even using them as tool compounds. Given a choice, we'd just rather work on something else. . .

Comments (7) + TrackBacks (0) | Category: Drug Assays | Drug Development | The Scientific Literature

November 18, 2011

Pushing Onwards with CETP: The Big Money and the Big Risks

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Posted by Derek

Remember torcetrapib? Pfizer always will. The late Phase III failure of that CETP inhibitor wiped out their chances for an even bigger HDL-raising follow-up to LDL-lowering Lipitor, the world's biggest drug, and changed the future of the company in ways that are still being played out.

But CETP inhibition still makes sense, biochemically. And the market for increasing HDL levels is just as huge as it ever was, since there's still no good way to do it. Merck is pressing ahead with anacetrapib, Roche with dalcetrapib, and Lilly is out with recent data on evacetrapib. All three companies have tried to learn as much as they could from Pfizer's disaster, and are keeping a close eye on the best guesses for why it happened (a small rise in blood pressure and changes in aldosterone levels). So far, so good - but that only takes you so far. Those toxicological changes are reasonable, but they're only hypotheses for why torcetrapib showed a higher death rate in the drug treatment group than it did in the controls. And even that only takes you up to the big questions.

Which are: will raising HDL really make a difference in cardiovascular morbidity and mortality? And if so, is inhibiting CETP the right way to do it? Human lipidology is not nearly as well worked out as some people might think it is, and these are both still very open questions. But such drugs, and such trials, are the only way that we're going to find out the answers. All three companies are risking hundreds of millions of dollars (in an area that's already had one catastrophe) in an effort to find out, and (to be sure) in the hope of making billions of dollars if they're correct.

Will anyone make it through? Will they fail for tox like Pfizer did, telling us that we don't understand CETP inhibitors? Or will they make it past that problem, but not help patients as much as expected, telling us that we don't understand CETP itself, or HDL? Or will all three work as hoped, and arrive in time to split up the market ferociously, making none of them as profitable as the companies might have wanted? If you want to see what big-time drug development is like, I can't think of a better field to illustrate it.

Comments (17) + TrackBacks (0) | Category: Cardiovascular Disease | Drug Development | Toxicology

October 31, 2011

"You Guys Don’t Do Innovation. The iPad. That’s Innovative"

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Posted by Derek

Thoughts from Matthew Herper at Forbes about Steve Jobs, modern medicine, what innovation means, and why it can be so hard in some fields. This is relevant to this post and its precursors.

Comments (41) + TrackBacks (0) | Category: Drug Development | Who Discovers and Why

October 26, 2011

Francis Collins Speaks

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Posted by Derek

With all the recent talk about the NIH's translational research efforts, and the controversy about their drug screening efforts, this seems like a good time to note this interview with Francis Collins over at BioCentury TV. (It's currently the lead video, but you'll be able to find it in their "Show Guide" afterwards as well).

Collins says that they're not trying to compete with the private sector, but taking a look at the drug development process "the way an engineer would", which takes me back to this morning's post re: Andy Grove. One thing he emphasizes is that he believes that the failure rate is too high because the wrong targets are being picked, and that target validation would be a good thing to improve.

He's also beating the drum for new targets to come out of more sequencing of human genomes, but that's something I'll reserve judgment on. The second clip has some discussion of the DARPA-backed toxicology chip and some questions on repurposing existing drugs. The third clip talks about the FDA's role in all this, and tries to clarify what NIH's role would be in outlicensing any discoveries. (Collins also admits along the way that the whole NCATS proposal has needed some clarifying as well, and doesn't sound happy with some of the press coverage).

Part 5 (part 4 is just a short wrap-up) discusses the current funding environment, and then moves into ethics and conflicts of interest - other people's conflicts, I should note. Worth a lunchtime look!

Comments (16) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development

A Note to Andy Grove

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Posted by Derek

Readers will recall my occasional pieces on Intel legend Andy Grove's idea for drug discovery. (The first one wasn't too complimentary; the second was a bit more neutral). You always wonder, when you have a blog, if the people you're writing about have a chance to see what you've said - well, in this case, that question's been answered. Here's a recent article by Lisa Krieger in the San Jose Mercury News, detailing Grove's thoughts on medical innovation. Near the end, there's this:

Some biotech insiders are angered by Grove's dismissal of their dedication to the cause.

"It would be daft to suggest that if biopharma simply followed the lead of the semiconductor industry, all would be well," wrote Kevin Davies in the online journal Bio-IT World.com. "The semiconductor industry doesn't have the complex physiology of the human body -- or the FDA, for that matter, to contend with."

In his blog "In The Pipeline," biochemist Derek Lowe called Grove "rich, famous, smart and wrong." Grove's recent editorial, Lowe said, "is not a crazy idea, but I think it still needs some work. ... The details of it, which slide by very quickly in Grove's article, are the real problems. Aren't they always?"

Grove sighed.

"Sticks and stones. ... There were brutal comments but I don't care. The typical comment is 'Chips are not people, go (expletive) yourself.' But to not look over to the other side to see what other people in other professions have done -- that is a lazy intellectual activity."

My purpose in these posts, of course, has not been to insult Andy Grove. That doesn't get any of us anywhere. What I'd like to do, though, since he's clearly sincere about trying to speed up the pace of drug discovery (and with good reason), is to help get him up to speed on what it's like to actually discover drugs. It's not his field; it is mine. But I should note here that being an "expert" in drug discovery doesn't exactly give you a lot of great tools to insure success, unfortunately. What it does give you is the rough location of a lot of sinkholes that you might want to try to avoid. ("So you can go plunge into new, unexplored sinkholes", says a voice from the back.)

Grove's certainly a man worth taking seriously, and I hope that he, in turn, takes seriously those of us over here in the drug industry. This really is a strange business, and it's worth getting to know it. People like me - and there are still a lot of us, although it seems from all the layoffs that there are fewer every month - are the equivalents of the chip designers and production engineers at Intel. We have one foot in the labs, trying to troubleshoot this or that process, and figure out what the latest results mean. And we have one foot in the offices, where we try to see where the whole effort is going, and where it should go next. I think that perspectives from this level of drug research would be useful for someone like Andy Grove to experience: not so far down in the details that you can't see the sky, but not so far up in the air that all you see are the big, sweeping vistas.

And conversely, I think that we should take him up on his offer to look at what people in the chip industry (and others) have done. It can't hurt; we definitely need all the help we can get over here. I can't, off the top of my head, see many things that we could pick up on, for the reasons given in those earlier posts, but then again, I haven't worked over there, in the same way that Andy Grove hasn't worked over here. It's worth a try - and if anyone out there in the readership (journalist, engineer, what have you) would like to forward that on to Grove himself, please do. I'm always surprised at just how many people around the industry read this site, and to start a big discussion among people who actually do drug discovery, you could do worse.

Comments (46) + TrackBacks (0) | Category: Drug Development

October 17, 2011

Harvard to the Rescue

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Posted by Derek

Harvard is announcing a big initiative in systems biology, which is an interdisciplinary opportunity if there ever was one.

The Initiative in Systems Pharmacology is a signature component of the HMS Program in Translational Science and Therapeutics. There are two broad goals: first, to increase significantly our knowledge of human disease mechanisms, the nature of heterogeneity of disease expression in different individuals, and how therapeutics act in the human system; and second — based on this knowledge — to provide more effective translation of ideas to our patients, by improving the quality of drug candidates as they enter the clinical testing and regulatory approval process, thereby aiming to increase the number of efficacious diagnostics and therapies reaching patients.

All worthy stuff, of course. But there are a few questions that come up. These drug candidates that Harvard is going to be improving the quality of. . .whose are those, exactly? Harvard doesn't develop drugs, you know, although you might not realize that if you just read the press releases. And the e-mail announcement sent out to the Harvard Medical School list is rather less modest about the whole effort:

With this Initiative in Systems Pharmacology, Harvard Medical School is reframing classical pharmacology and marshaling its unparalleled intellectual resources to take a novel approach to an urgent problem: The alarming slowdown in development of new and lifesaving drugs.

A better understanding of the whole system of biological molecules that controls medically important biological behavior, and the effects of drugs on that system, will help to identify the best drug targets and biomarkers. This will help to select earlier the most promising drug candidates, ultimately making drug discovery and development faster, cheaper and more effective. A deeper understanding will also help clinicians personalize drug therapies, making better use of medicine we already have.

Again with all those drug candidates - and again, whose candidates are they going to be selecting? Don't get me wrong; I actually wish everyone well in this effort. There really are a lot of excellent scientists at Harvard, even if they tell you so, and this is the sort of problem that can take (and has taken) everything that people can throw at it. But it's also worth remembering Harvard's approach to licensing and industrial collaboration. It's. . .well, let's just say that they didn't get that endowment up to its present size by letting much slip through their fingers. Many are those who've negotiated with the university and come away wanting to add ". . .et Pecunia" to that Latin motto.

So we'll see what comes out of this. But Harvard Medical School is indeed on the case.

Comments (41) + TrackBacks (0) | Category: Drug Development

October 11, 2011

Too Many Cancer Drugs? Too Few? About Right?

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Posted by Derek

According to Bruce Booth (@LifeSciVC on Twitter), Ernst & Young have estimated the proportion of drugs in the clinic in the US that are targeting cancer. Anyone want to pause for a moment to make a mental estimate of their own?

Well, I can tell you that I was a bit low. The E&Y number is 44%. The first thought I have is that I'd like to see that in some historical perspective, because I'd guess that it's been climbing for at least ten years now. My second thought is to wonder if that number is too high - no, not whether the estimate is too high. Assuming that the estimate is correct, is that too high a proportion of drug research being spent in oncology, or not?

Several factors led to the rise in the first place - lots of potential targets, ability to charge a lot for anything effective, an overall shorter and more definitive clinical pathway, no need for huge expensive ad campaigns to reach the specialists. Have these caused us to overshoot?

Comments (22) + TrackBacks (0) | Category: Cancer | Clinical Trials | Drug Development | Drug Industry History

October 7, 2011

Different Drug Companies Make Rather Different Compounds

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Posted by Derek

Now here's a paper, packed to the edges with data, on what kinds of drug candidate compounds different companies produce. The authors assembled their list via the best method available to outsiders: they looked at what compounds are exemplified in patent filings

What they find is that over the 2000-2010 period that not much change has taken place, on average, in the properties of the molecules that are showing up. Note that we're assuming, for purposes of discussion, that these properties - things like molecular weight, logP, polar surface area, amount of aromaticity - are relevant. I'd have to say that they are. They're not the end of the discussion, because there are plenty of drugs that violate one or more of these criteria. But there are even more that don't, and given the finite amount of time and money we have to work with, you're probably better off approaching a new target with five hundred thousand compounds that are well within the drug-like properties boxes rather than five hundred thousand that aren't. And at the other end of things, you're probably better off with ten clinical candidates that mostly fit versus ten that mostly don't.

But even if overall properties don't seem to be changing much, that doesn't mean that there aren't differences between companies. That's actually the main thrust of the paper: the authors compare Abbott, Amgen, AstraZeneca, Bayer-Schering, Boehringer, Bristol-Myers Squibb, GlaxoSmithKline, J&J, Lilly, Merck, Novartis, Pfizer, Roche, Sanofi, Schering-Plough, Takeda, Wyeth, and Vertex. Of course, these organizations filed different numbers of patents, on different targets, with different numbers of compounds. For the record, Merck and GSK filed the most patents during those ten years (over 1500), while Amgen and Takeda filed the fewest (under 300). Merck and BMS had the largest number of unique compounds (over 70,000), and Takeda and Bayer-Schering had the fewest (in the low 20,000s). I should note that AstraZeneca just missed the top two in both patents and compounds.
radar%20plot.jpg
If you just look at the raw numbers, ignoring targeting and therapeutic areas, Wyeth, Bayer-Schering, and Novartis come out looking the worst for properties, while Vertex and Pfizer look the best. But what's interesting is that even after you correct for targets and the like, that organizations still differ quite a bit in the sorts of compounds that they turn out. Takeda, Lilly, and Wyeth, for example, were at the top of the cLogP rankings (numberically, "top" meaning the greasiest). Meanwhile, Vertex, Pfizer, and AstraZeneca were at the other end of the scale in cLogP. In molecular weight, Novartis, Boehringer, and Schering-Plough were at the high end (up around 475), while Vertex was at the low end (around 425). I'm showing a radar-style plot from the paper where they cover several different target-unbiased properties (which have been normalized for scale), and you can see that different companies do cover very different sorts of space. (The numbers next to the company names are the total number of shared targets found and the total number of shared-target observations used - see the paper if you need more details on how they compiled the numbers).

Now, it's fair to ask how relevant the whole sweep of patented compounds might be, since only a few ever make it deep into the clinic. And some companies just have different IP approaches, patenting more broadly or narrowly. But there's an interesting comparison near the end of the paper, where the authors take a look at the set of patents that cover only single compounds. Now, those are things that someone has truly found interesting and worth extra layers of IP protection, and they average to significantly lower molecular weights, cLogP values, and number of rotatable bonds than the general run of patented compounds. Which just gets back to the points I was making in the first paragraph - other things being equal, that's where you'd want to spend more of your time and money.

What's odd is that the trends over the last ten years haven't been more pronounced. As the paper puts it:

blockquote>Over the past decade, the mean overall physico-chemical space used by many pharmaceutical companies has not changed substantially, and the overall output remains worryingly at the periphery of historical oral drug chemical space. This is despite the fact that potential candidate drugs, identified in patents protecting single compounds, seem to reflect physiological and developmental pressures, as they have improved drug-like properties relative to the full industry patent portfolio. Given these facts, and the established influence of molecular properties on ADMET risks and pipeline progression, it remains surprising that many organizations are not adjusting their strategies.

The big question that this paper leaves unanswered, because there's no way for them to answer it, is how these inter-organizational differences get going and how they continue. I'll add my speculations in another post - but speculations they will be.

Comments (30) + TrackBacks (0) | Category: Drug Assays | Drug Development | Drug Industry History

September 2, 2011

How Many New Drug Targets Aren't Even Real?

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Posted by Derek

So, are half the interesting new results in the medical/biology/med-chem literature impossible to reproduce? I linked earlier this year to an informal estimate from venture capitalist Bruce Booth, who said that this was his (and others') experience in the business. Now comes a new study from Bayer Pharmaceuticals that helps put some backing behind those numbers.

To mitigate some of the risks of such investments ultimately being wasted, most pharmaceutical companies run in-house target validation programmes. However, validation projects that were started in our company based on exciting published data have often resulted in disillusionment when key data could not be reproduced. Talking to scientists, both in academia and in industry, there seems to be a general impression that many results that are published are hard to reproduce. However, there is an imbalance between this apparently widespread impression and its public recognition. . .

Yes, indeed. The authors looked back at the last four years worth of oncology, women's health, and cardiovascular target validation efforts inside Bayer (this would put it right after they combined with Schering AG of Berlin). They surveyed all the scientists involved in early drug discovery in those areas, and had them tally up the literature results they'd acted on and whether they'd panned out or not. I should note that this is the perfect place to generate such numbers, since the industry scientists are not in it for publication glory, grant applications, or tenure reviews: they're interested in finding drug targets that look like they can be prosecuted, in order to find drugs that could make them money. You may or may not find those to be pure or admirable motives (I have no problem at all with them, personally!), but I think we can all agree that they're direct and understandable ones. And they may be a bit orthogonal to the motives that led to the initial publications. . .so, are they? The results:

"We received input from 23 scientists (heads of laboratories) and collected data from 67 projects, most of them (47) from the field of oncology. This analysis revealed that only in ~20–25% of the projects were the relevant published data completely in line with our in-house findings. In almost two-thirds of the projects, there were inconsistencies between published data and in-house data that either considerably prolonged the duration of the target validation process or, in most cases, resulted in termination of the projects. . ."

So Booth's estimate may actually have been too generous. How does this gap get so wide? The authors suggest a number of plausible reasons: small sample sizes in the original papers, leading to statistical problems, for one. The pressure to publish in academia has to be a huge part of the problem - you get something good, something hot, and you write that stuff up for the best journal you can get it into - right? And it's really only the positive results that you hear about in the literature in general, which can extend so far as (consciously or unconsciously) publishing just on the parts that worked. Or looked like they worked.

But the Bayer team is not alleging fraud - just irreproducibility. And it seems clear that irreproducibility is a bigger problem than a lot of people realize. But that's the way that science works, or is supposed to. When you see some neat new result, your first thought should be "I wonder if that's true?" You may have no particular reason to doubt it, but in an area with as many potential problems as discovery of new drug targets, you don't need any particular reasons. Not all this stuff is real. You have to make every new idea perform the same tricks in front of your own audience, on your own stage under bright lights, before you get too excited.

Comments (51) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development

September 1, 2011

GlaxoSmithKline Reviews the Troops

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Posted by Derek

Several readers sent along this article from the Times of London (via the Ottawa Citizen) on GlaxoSmithKline's current research setup. You can tell that the company is trying to get press for this effort, because otherwise these are the sorts of internal arrangements that would never be in the newspapers. (The direct quotes from the various people in the article are also a clear sign that GSK wants the publicity).

The piece details the three-year cycle of the company's Drug Performance Units (DPUs), which have to come and justify their existence at those intervals. We're just now hitting the first three-year review, and as the article says, not all the DPUs are expected to make it through:

In 2008, the company organized its scientists into small teams, some with just a handful of staff, and set them to work on different diseases. At the time, every one of these drug performance units (DPUs) had to plead its case for a slice of Glaxo’s four-billion-pound research and development budget. Three years on and each of the 38 DPUs is having to plead its case for another dollop of funding to 2014. . .

. . .Such a far-reaching overhaul of a fundamental part of the business has proved painful to achieve. Witty said: “If you look across research and development at Glaxo, I would say we are night-and-day different from where we were three, four, five years ago. It has been a tough period of change and challenge for people in the company. When you go through that period, of course there are moments when morale is challenged and people are worried about what will happen.”

But he said it has been worth the upheaval: “The research and development organization has never been healthier in terms of its performance and in terms of its potential.”

I'm not in a position to say whether he's right or not. One problem (mentioned by an executive in the story) is that three years isn't really long enough to say whether things are working out or not. That might give you a read on the number of preclinical projects, whether that seems to be increasing or not. But that number is notoriously easy to jigger around - just lower the bar a bit, and your productivity problem is solved, on paper. The big question is the quality of those compounds and projects, and that takes a lot more time to evaluate. And then there's the problem that the extent that you can actually improve that quality may still not be enough to really affect your clinical failure rates much, anyway, depending on the therapeutic area.

Is this a sound idea, though? It could be - asking projects and therapeutic areas to justify their existence every so often could keep them from going off the rails and motivate them to produce results. Or, on the other hand, it could motivate them to tell management exactly what they want to hear, whether that corresponds to reality or not. All of these tools can cut in both directions, and I've no idea which way the blades are moving at GSK.

There's another consideration that applies to any new management scheme. How long will GSK give this system? How many three-year cycles will be needed to really say if it's effective, and how many will actually be run? Has any big drug company kept its R&D arrangements stable for as long as nine years, say, in recent history?

Comments (35) + TrackBacks (0) | Category: Drug Development | Drug Industry History

August 29, 2011

Chinese Pharma: No Shortage of Ambition, Anyway

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Posted by Derek

When does China take the next step in drug research? They already have a huge contract research industry, and they have branches of many of the major pharma companies. But when does a Chinese startup, doing its own research with its own people in China, develop its own international-level drug pipeline? (We'll leave aside the problem that not even all the traditional drug companies seem to be able to do that these days). It still seems clear that we're eventually going to have a Chinese Merck, or a Chinese Novartis or what have you - a company to join North America, Western Europe, and Japan in the big leagues. The Chinese government, especially, would seem to find this idea very appealing.

Opinions differ, to put it mildly, about how far away this prospect is. But Chemical and Engineering News is out with an article on homegrown Chinese research that explores just this sort of question. But you run into passages like this:

In a meeting room in a building resembling a residential home in Shanghai’s Zhangjiang Hi-Tech Park, Li Chen and John Choi describe the business plan of their new company. Called Hua Medicine, the firm will launch breakthrough drugs within four years, they predict. Hua will manufacture the compounds and sell them with its own sales force. It will also license its internally developed drugs to multinational companies.

Yet right now, Hua is a modest operation that employs eight people. Hua doesn’t have an R&D lab yet, let alone a manufacturing facility. It operates in a loaned building formerly used by the administrators of the industrial park...

It can be easy to dismiss such ambitious business plans as simply talk aimed at gullible investors or government officials handing out subsidies. Except several start-ups are led by people who have long track records of success. Moreover, the money financing these start-ups comes not from relatives and friends, but from savvy investors knowledgeable about the drug industry.

Well. . .yeah. Let me join those who dismiss business plans that are as ambitious as that one. The way I understand the drug industry, if you're planning on launching a breakthrough drug within four years, you must have that drug in your hand right now, and it has to have had a lot of preclinical work done on it already (and in most therapeutic areas, it needs to have already hit the clinic). And note, these guys aren't talking about their one pet compound, they're talking about launching drugs, plural. Drugs that they discover, develop, manufacture and sell. And they have 8 people and no labs.

No, something is off here. I get the same feeling from this that I get from a lot of leapfrog-the-world plans, the feeling that something just isn't quite right and that the world doesn't allow itself to be hopped over on such a deliberate schedule. Thoughts?

Comments (47) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

August 5, 2011

Bernard Munos Rides Again

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Posted by Derek

I've been meaning to link to Matthew Herper's piece on Bernard Munos and his ideas on what's wrong with the drug business. Readers will recall several long discussions here about Munos and his published thoughts (Parts one, two, three and four). A take-home message:

So how can companies avoid tossing away billions on medicines that won’t work? By picking better targets. Munos says the companies that have done best made very big bets in untrammeled areas of pharmacology. . .Munos also showed that mergers—endemic in the industry—don’t fix productivity and may actually hurt it. . . What correlated most with the number of new drugs approved was the total number of companies in the industry. More companies, more successful drugs.

I should note that the last time I saw Munos, he was emphasizing that these big bets need to be in areas where you can get a solid answer in the clinic in the shortest amount of time possible - otherwise, you're really setting yourself up with too much risk. Alzheimer's, for example, is a disease that he was advising that drug developers basically stay away from: tricky unanswered medical questions, tough drug development problems, followed up by big huge long expensive clinical trials. If you're going to jump into a wild, untamed medical area (as he says you should), then pick one where you don't have to spend years in the clinic. (And yes, this would seem to mean a focus on an awful lot of orphan diseases, the way I look at it).

But, as the article goes on to say, the next thought after all this is: why do your researchers need to be in the same building? Or the same site? Or in the same company? Why not spin out the various areas and programs as much as possible, so that as many new ideas get tried out as can be tried? One way to interpret that is "Outsource everything!" which is where a lot of people jump off the bus. But he's not thinking in terms of "Keep lots of central control and make other people do all your grunt work". His take is more radical:

(Munos) points to the Pentagon’s Defense Advanced Research Projects Agency, the innovation engine of the military, which developed GPS, night vision and biosensors with a staff of only 140 people—and vast imagination. What if drug companies acted that way? What areas of medicine might be revolutionized?

DARPA is a very interesting case, which a lot of people have sought to emulate. From what I know of them, their success has indeed been through funding - lightly funding - an awful lot of ideas, and basically giving them just enough money to try to prove their worth before doling out any more. They have not been afraid of going after a lot of things that might be considered "out there", which is to their credit. But neither have they been charged with making money, much less reporting earnings quarterly. I don't really know what the intersection of DARPA and a publicly traded company might look like (the old Bell Labs?), or if that's possible today. If it isn't, so much the worse for us, most likely.

Comments (114) + TrackBacks (0) | Category: Alzheimer's Disease | Business and Markets | Clinical Trials | Drug Development | Drug Industry History | Who Discovers and Why

July 29, 2011

2011 Drug Approvals Are Up: We Rule, Right?

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Posted by Derek

I've been meaning to comment on this article from the Wall Street Journal - the authors take a look at the drug approval numbers so far this year, and speculate that the industry is turning around.

Well, put me in the "not so fast" category. And I have plenty of company there. Neither Bruce Booth (from the venture capital end), John LaMattina (ex-Pfizer R&D head) nor Matthew Herper at Forbes are buying it either.

One of the biggest problems with the WSJ thesis is that most of these drugs have been in development for longer than the authors seem to think. Bruce Booth's post goes over this in detail, and he's surely correct that these drugs were basically all born in the 1990s. Nothing that's changed in the research labs in the last 5 to 10 years is likely to have significantly affected their course; we're going to have to wait several more years to see any effects. (And even then it's unlikely that we're going to get any unambiguous signals; there are too many variables in play). That, as many people have pointed out over the years, is one of the trickiest parts about drug R&D: the timelines are so long and complex that it's very hard to assign cause and effect to any big changes that you make. If your car only responds to the brake pedal and steering wheel a half hour after you touch them, how can you tell if that fancy new GPS you bought is doing you any good?

Comments (8) + TrackBacks (0) | Category: Drug Development | Drug Industry History | Press Coverage | Regulatory Affairs

July 20, 2011

Will Macrocycles Get It Done?

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Posted by Derek

Here's an article from Xconomy on Ensemble Therapeutics, a company that spun off from work in David Liu's lab at Harvard. Their focus these days is on a huge library of macrocyclic compounds (prepared by using DNA tags to bring the reactants together, which is a topic for a whole different post). They're screening against several targets, and with several partners. Why macrocycles?

Well, there's been a persistent belief, with some evidence behind it, that medium- and large-ring compounds are somehow different. Cyclic peptides certainly can be distinguished from their linear counterparts - some of that can be explained by their being unnatural (and poor) substrates for some of the proteases that would normally clear them out, but there can be differences in distribution and cell penetration as well. The great majority of non-peptidic macrocycles that have been studied in biological systems are natural products - plenty of classic antibiotics and the like are large rings. I worked on one for my PhD, although I never quite closed the ring on the sucker.

You can look that that natural product distribution in two ways: one view might be that we have an exaggerated idea of the hit rate of macrocycles, because we've been looking at a bunch of evolutionarily optimized compounds. But the other argument is that macrocycles aren't all that easy to make, therefore evolutionary pressures must have led to so many of them for some good reasons, and we should try to take advantage of the evidence that's in front of us.

What's for sure is that macrocyclic compounds are under-represented in drug industry screening collections, so there's an argument to be made just on that basis. (You do see them once in a while). And the chemical space that they cover is probably not something that other compounds can easily pick up. Large rings are a bit peculiar - they have some conformational flexibility, in most cases, but only within a limited range. So if you're broadly in the right space for hitting a drug target, you probably won't pay as big an entropic penalty when a macrocycle binds. It already had its wings clipped to start with. And as mentioned above, there's evidence that these compounds can do a better job of crossing membranes than you'd guess from their size and functionality. One hope is that these properties will allow molecular weight ranges to be safely pushed up a bit, allowing a better chance for hitting nontraditional targets such as protein-protein interactions.

All this has led to a revival of med-chem interest in the field, so Ensemble is selling their wares at just the right time. One reason that there haven't been so many macrocycles in the screening decks is that they haven't been all that easy to make. But besides Liu's DNA templating, some other interesting synthetic methods have been coming along - the Nobel-worthy olefin metathesis reaction has been recognized for some time as a good entry into the area, and Keith James out at Scripps has been publishing on macrocyclic triazoles via the copper-catalyzed click reaction. Here's a recent review in J. Med. Chem., and here's another. It's going to be interesting to see how this all works out - and it's also a safe bet that this won't be the only neglected and tricky area that we're going to find ourselves paying more attention to. . .

Comments (31) + TrackBacks (0) | Category: Chemical News | Drug Development

July 7, 2011

Phenotypic Screening For the Win

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Posted by Derek

Here's another new article in Nature Reviews Drug Discovery that (for once) isn't titled something like "The Productivity Crisis in Drug Research: Hire Us And We'll Consult Your Problems Away". This one is a look back at where drugs have come from.

Looking over drug approvals (259 of them) between 1999 and 2008, the authors find that phenotypic screens account for a surprising number of the winners. (For those not in the business, a phenotypic screen is one where you give compounds to some cell- or animal-based assay and look for effects. That's in contrast to the target-based approach, where you identify some sort of target as being likely important in a given disease state and set out to find a molecule to affect it. Phenotypic screens were the only kinds around in the old days (before, say, the mid-1970s or thereabouts), but they've been making a comeback - see below!)

Out of the 259 approvals, there were 75 first-in-class drugs and 164 followers (the rest were imaging agents and the like). 100 of the total were discovered using target-based approaches, 58 through phenotypic approaches, and 18 through modifying natural substances. There were also 56 biologics, which were all assigned to the target-based category. But out of the first-in-class small molecules, 28 of them could be assigned to phenotypic assays and only 17 to target-based approaches. Considering how strongly tilted the industry has been toward target-based drug discovery, that's really disproportionate. CNS and infectious disease were the therapeutic areas that benefited the most from phenotypic screening, which makes sense. We really don't understand the targets and mechanisms in the former, and the latter provide what are probably the most straightforward and meaningful phenotypic assays in the whole business. The authors' conclusion:

(this) leads us to propose that a focus on target-based drug discovery, without accounting sufficiently for the MMOA (molecular mechanism of action) of small-molecule first-in-class medicines, could be a technical reason contributing to high attrition rates. Our reasoning for this proposal is that the MMOA is a key factor for the success of all approaches, but is addressed in different ways and at different points in the various approaches. . .

. . .The increased reliance on hypothesis-driven target-based approaches in drug discovery has coincided with the sequencing of the human genome and an apparent belief by some that every target can provide the basis for a drug. As such, research across the pharmaceutical industry as well as academic institutions has increasingly focused on targets, arguably at the expense of the development of preclinical assays that translate more effectively into clinical effects in patients with a specific disease.

I have to say, I agree (and have said so here on the blog before). It's good to see some numbers put to that belief, though. This, in fact, was the reason why I thought that the NIH funding for translational research might be partly spent on new phenotypic approaches. Will we look back on the late 20th century/early 21st as a target-based detour in drug discovery?

Comments (36) + TrackBacks (0) | Category: Drug Assays | Drug Development | Drug Industry History

July 2, 2011

Innovation and Return (Europe vs. the US)

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Posted by Derek

Here's another look at the productivity problems in drug R&D. The authors are looking at attrition rates, development timelines, targets and therapeutic areas, and trying to find some trends to explain (or at least illuminate) what's been going on.

Their take? Attrition rates have been rising at all phases of drug development, and most steeply in Phase III. (This sounds right to me). Here are their charts:
Attrition%20rates.png
And when they look at where the drug R&D efforts have been going, they find that comparatively more time and money has been spent on targets with lower probability of success. That means (among other things) more oncology, Alzheimer's, arthritis, Parkinson's et al. and less cardiovascular and anti-HIV.

That makes sense, too, in a paradoxical way. If we were to get drugs in those areas, the expected returns would be higher than if we found them in the well-established ones. The regulatory barriers would be smaller, the competition thinner, the potential markets are enthusiastic about new therapies - everything's lined up. If you can find a drug, that is. The problem is the higher failure rates. We knew that going in, of course, but the expectation was that the greater rewards would cancel that out. But what if they don't? What if, for a protracted period, there are no rewards at all?

The paper also has a very interesting analysis of European firms versus US ones. Instead of looking at where companies might be headquartered, the authors used the addresses of the inventors on patent filings as a better location indicator. Over 18,000 projects started by companies or public research organizations between 1990 and 2007 were examined, and they found:

Although at a first glance, European organizations seem to have higher success rates compared with US organizations, after controlling for the larger share of biotechnology companies and PROs in the United States and for differences in the composition of R&D portfolios, there is no significant gap between European and US organizations in this respect. Unconditional differences (that is, differences arising when no controls are taken into account) are driven by the higher propensity of US organizations to focus on novel R&D methodologies and riskier therapeutic endeavours. . .as an average US organization takes more risk, when successful, they attain higher price premiums than the European organizations.

The other take-home has to do with "me-too" compounds versus first-in-class ones, and is worth considering:

". . .both private and public payers discourage incremental innovation and investments in follow-on drugs in already established therapeutic classes, mostly by the use of reference pricing schemes and bids designed to maximize the intensity of price competition among different molecules. Indeed, in established markets, innovative patented drugs are often reimbursed at the same level as older drugs. As a consequence, R&D investments tend to focus on new therapeutic targets, which are characterized by high uncertainty and difficulty, but lower expected post-launch competition. Our empirical investigation indicates that this reorienting of investments accounts for most of the recent decline in productivity in pharmaceutical R&D, as measured in terms of attrition rates, development times and the number of NMEs launched."

So, rather than being in trouble for not trying to be innovative enough, according to these guys, we're in trouble for innovating too much. . .

Comments (26) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

June 28, 2011

Drug R&D Spending Now Down (But Look at the History)

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Posted by Derek

I hate to be such a shining beacon of happiness today, but this news can't very well be ignored, can it? For the first time ever, total drug R&D spending seems to have declined:

The global drug industry cut its research spending for the first time ever in 2010, after decades of relentless increases, and the pace of decline looks set to quicken this year.

Overall expenditure on discovering and developing new medicines amounted to an estimated $68 billion last year, down nearly 3 percent on the $70 billion spent in both 2008 and 2009, according to Thomson Reuters data released on Monday.

The fall reflects a growing disillusionment with poor returns on pharmaceutical R&D. Disappointing research productivity is arguably the biggest single factor behind the declining valuations of the sector over the past decade.

This is not good - although, to be sure, we've had plenty of warning that this day would be coming. But looking at it from another perspective, you might wonder what's taken so long. Matthew Herper has a piece up highlighting the chart below, from the Boston Consulting Group. It plots new drugs versus R&D spending in constant dollars, and if you're wondering what the Good Old Days looked like, here they are. Or were:
R%26D%20constant%20dollar%20graph.png
What's most intriguing to me about this graph is the way it seems to validate the "low-hanging fruit" argument. This looks like the course of an industry that has, from the very beginning of its modern era, been finding it steadily, relentlessly harder to mine the ore that it runs on. But that analogy leaves out another key factor that makes that line go down: good drugs don't go away. They just go generic, and get cheaper than ever. You can also interpret this graph as showing the gradual buildup of cheap, effective generics for a number of major conditions (cardiovascular, in particular).

There's one other factor that ties in with those thoughts - the therapeutic areas that we've been able to address. Look at that spike in the 1990s, labeled PDUFA and HIV. Part of that jump is, as a colleague theorized with me just this morning, the fact that a completely new disease appeared. And it was one that, in the end, we could do something about - as opposed to, say, Alzheimer's. So if you want to be completely evil about it, then the Huey Lewis model of fixing pharma has it wrong: we don't need a new drug. We need a new disease. Or several.

Well, that's clearly not the way to look at it. I don't actually think that we need to add to the list of human ailments; it's long enough already. But given all the factors listed (and the ever-tightening regulatory/safety environment, on top of them), another colleague of mine looked at this chart and asked if we ever could have expected it to look any different. Could that line go anywhere else but down? The promise of things like the genomics frenzy was, I think, that it would turn things around (and that hope still lives on in the heart of Francis Collins), even though some people argue that it did the reverse.

Comments (60) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

June 16, 2011

What Translational Research Should Academia Do?

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Posted by Derek

We've talked quite a bit around here about academic (and nonindustrial) drug discovery, but those posts have mostly divided into two parts. There's the early-stage discovery work that really gets done in some places, and then there's the proposal for the big push into translational research by the NIH. That, broadly defined, is (a) the process of turning an interesting idea into a real drug target, or (b) turning an interesting compound into a real drug. One of the things that the recent survey of academic centers made clear, I'd say, is that the latter kind of work is hardly being done at all outside of industry. The former is a bit more common, but still suffers from the general academic bias: walking away too soon in order to move on to the next interesting thing. Both these translational processes involve a lot of laborious detail work, of the kind that does not mint fresh PhDs nor energize the post-docs.

But if there's funding to do it, it'll get done in some fashion, and we can expect to see a lot of people trying their hand at these things. Many universities are all for it, too, since they imagine that there will be some lucrative technology transfers waiting at the end of the process. (One of the remarkable things about the drug industry is how many people outside it see it as the place to get rich).

I had an e-mail from Jonathan Gitlin on this subject, who asks the question: if academia is going to do these things, what should they be doing to keep the money from being wasted? It's definitely worth thinking about, since there are so many drains for the money to go spiraling down. Mind you, most money spent on these things is (in the most immediate sense) wasted, since most ideas for drug targets turn out to be mistaken, and most compounds turn out not to be drugs. No matter what, we're going to have to be braced for that - even strong improvements in both those percentages would still leave us with what (to people with fresh eyes) would seem horrific failure rates.

And what I'd really like is for people to avoid the "translational research fallacy", as I've called it. That's the (seemingly pervasive) idea that there are just all sorts of great ideas for new drugs and new targets just gathering dust on university shelves, waiting for some big drug company to get around to noticing them. That, unfortunately, does not seem to be true, but it's a tempting idea, and I worry that people are going to be unable to resist chasing after it.

But that said, where would be the best place for the academic money to go? I have a few nominees. If we're breaking things down by therapeutic area, one of the most intractable and underserved is central nervous system disease. I note that there's already talk of a funding crisis in this area (although that article is more focused on Europe). It may come as a surprise to people outside medical research, but we still have very little concrete knowledge of what goes on in the brain during depression, schizophrenia, and other illnesses. That, unfortunately, is not for lack of trying. Looked at from the other end, we know vastly more than we used to, but it's still nowhere near enough.

If we're looking at general translational platforms and ideas, then I would suggest trying to come up with solid small-organism models for phenotypic screening. A good phenotypic screen, where you run compounds past a living system to see which ones give you the effects you want, can be a wonderful thing, since it doesn't depend on you having to unravel all the biochemistry behind a disease process. (It can, in fact, reveal biochemistry that you never knew existed). But good screens of this type are rare, outside of the infectious disease area, and are tricky to validate. Everyone would love to have more of them - and if an academic lab can come up with one, then those folks can naturally have first crack at screening a compound collection past them.

More suggestions welcome in the comments - it looks like this is going to happen, so perhaps we can at least seed this newly plowed field with something that we'd like to see when it sprouts.

Comments (26) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Development

May 31, 2011

Extreme Outsourcing

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Posted by Derek

My local NPR station had this report on this morning, on one-person drug companies. Can't outsource much more than that!

Here are the two companies profiled: LipimetiX and Deuteria. The former is using helical peptides to affect lipoprotein clearance, and the latter is (as you'd guess) in the deuterated-drug game, which I've most recently blogged on here. (That one's run by Sheila DeWitt, who used to work down the hall from me in grad school 25 years ago). And there are several other outfits that they could have mentioned - some of them are not quite down to one person, but you can count the employees on your fingers. In all of these cases, everything is being contracted out.

There are downsides, of course. For one thing, these are, almost by necessity, single-drug companies. It's enough of a strain just getting one project through under those conditions, let alone running a whole portfolio. So the risk is higher, given the typical failure rates in this line of work. And you have to trust your contractors, naturally. That's a bit easier to do in the Boston area (and a few other places), since you can get a lot of work sourced locally. That doesn't make it as much of a Bargain, Bargain, Bargain as it might be overseas, but at least you can drop in and see how things are going.

Another thing the NPR piece didn't address was where these projects come from. Many of them, I'd guess, are abandoned efforts from other companies that still have some possibilities. Those and the up-from-academia ideas probably take care of the whole list, wouldn't you think? Has anyone heard of one of these virtual-company ideas where the lead compound came from some sort of outsourced screen? And is an outsourced screen even possible? Now there's a business idea. . .

Comments (24) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

May 26, 2011

Pfizer's Brave New Med-Chem World

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Posted by Derek

OK, here's how I understand the way that medicinal chemistry now works at Pfizer. This system has been coming on for quite a while now, and I don't know if it's been fully rolled out in every therapeutic area yet, but this seems to be The Future According to Groton:

Most compounds, and most actual chemistry bench work, is apparently going to be done at WuXi (or perhaps other contract houses?) Back here in the US, there will be a small group of experienced medicinal chemists at the bench, who will presumably be doing the stuff that can't be easily shipped out (time-critical, difficult chemistry, perhaps even IP-critical stuff, one wonders?) But these people are not, as far as I can tell, supposed to have ideas of their own.

No, ideas are for the Drug Designers, which is where the rest of Pfizer's remaining medicinal chemistry head count are to be found. These are the people who keep trac of the SAR, decided what needs to be made next, and tell the folks in China to make it. It's presumably their call, what to send away for and what to do in-house, but one gets the sense that they're strongly encouraged to ship as much stuff out as possible. Cheaper that way, right? And it's not like there's a whole lot of stateside capacity, anyway, at this point.

What if someone working in the lab has (against all odds) their own thoughts about where the chemistry should go next? I presume that they're going to have to go and consult a Drug Designer, thereby to get the official laying-on of hands. That process will probably work smoothly in some cases, but not so smoothly in others, depending on the personalities involved.

So we have one group of chemists that are supposed to be all hands and no head, and one group that's supposed to be all head and no hands. And although that seems to me to be carrying specialization one crucial step too far, well, it apparently doesn't seem that way to Pfizer's management, and they're putting a lot of money down on their convictions.

And what about the whole WuXi/China angle? The bench chemists there are certainly used to keeping their heads down and taking orders, for better or worse, so that won't be any different. But running entire projects outsourced can be a tricky business. You can end up in a situation where you feel as if you're in a car that only allows you to move the steering wheel every twenty minutes or so. Ah, a package has arrived, a big bunch of analogs that aren't so relevant any more, but what the heck. And that last order has to be modified, and fast, because we just got the assay numbers back, and the PK of the para substituted series now looks like it's not reproducing. And we're not sure if that nitrogen at the other end really needs to be modified any more at this point, but that's the chemistry that works, and we need to keep people busy over there, so another series of reductive aminations it is. . .

That's how I'm picturing it, anyway. It doesn't seem like a particularly attractive (or particularly efficient) picture to me, but it will at least appear to spend less money. What comes out the other end, though, we won't know for a few years. And who knows, someone may have changed their mind by then, anyway. . .

Comments (114) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Life in the Drug Labs

May 24, 2011

Maybe It Really Is That Hard?

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Posted by Derek

Here's an interesting note from the Wall Street Journal's Health Blog. I can't summarize it any better than they have:

"When former NIH head Elias Zerhouni ran the $30 billion federal research institute, he pushed for so-called translational research in which findings from basic lab research would be used to develop medicines and other applications that would help patients directly.

Now the head of R&D at French drug maker Sanofi, Zerhouni says that such “bench to bedside” research is more difficult than he thought."

And all across the industry, people are muttering "Do tell!" In fairness to Zerhouni, he was, in all likelihood, living in sort of a bubble at NIH. There probably weren't many people around him who'd ever actually done this sort of work, and unless you have, it's hard to picture just how tricky it is.

Zerhouuni is now pushing what he calls an "open innovation" model for Sanofi-Aventis. The details of this are a bit hazy, but it involves:

". . .looking for new research and ideas both internally and externally — for example, at universities and hospitals. In addition, the company is focusing on first understanding a disease and then figuring out what tools might be effective in treating it, rather than identifying a potential tool first and then looking for a disease area in which it could be helpful."

Well, I don't expect to see Sanofi's whole strategy laid out in the press, but that one doesn't even sound as impressive as it sounds. The "first understanding a disease" part sounds like what Novartis has been saying for some time now - and honestly, it really is one of the things that we need, but that understanding is painfully slow to dawn. Look at, oh, Alzheimer's, to pick one of those huge unmet medical needs that we'd really like to address in this business.

With a lot of these things, if you're going to first really understand them, you could have a couple of decades' wait on your hands, and that's if things go well. More likely, you'll end up doing what we've been doing: taking your best shot with what's known at the moment and hoping that you got something right. Which leads us to the success rates we have now.

On the other hand, maybe Zerhouni should just call up Marcia Angell or Donald Light, so that they can set him straight on the real costs of drug R&D. Why should we listen to a former head of the NIH who's now running a major industrial research department, when we can go to the folks who really know what they're talking about, right? And I'd also like to know what he thinks of Francis Collins' plan for a new NIH translational research institute, too, but we may not get to hear about that. . .

Comments (34) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Development | Drug Industry History

May 17, 2011

Imperfect Pitch

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Posted by Derek

Venture capitalist Bruce Booth has moved his blog over to the Forbes network, and in his latest post he has some solid advice for people who are preparing to pitch him (and people like him) some ideas for a new company. It's very sensible stuff, including the need to bring as much solid data as you can possibly bring, not to spend too much time talking about how great everyone on your team is, and not to set off the hype detectors. (Believe it, everyone who's dealt with early-stage biotech and pharma has a very sensitive, broad-spectrum hype detector, and the "off" switch stopped working a long time ago).

He also has some advice that might surprise people who haven't been watching the startup industry over the last few years: "Unless you are really convinced you have a special story that Wall Street will love, please don’t use that three-letter word synonymous with so much value destruction: I-P-O." That's the state of things these days, for better or worse - the preferred exit strategy is to do a good-sized deal with a larger company, and most likely to be bought outright.

And this is advice that I wish that more seminar speakers would follow, not just folks pitching a company proposal:

It's annoying when an entrepreneur touting a discovery-stage cancer program has multiple slides on how big the market is for cancer drugs, what the sales of Avastin were last year, what the annual incidence of the big four cancers are, etc… These slides give me a huge urge to reach for my Blackberry. We know cancer is huge. Unless you’ve got a particular angle on a disease or market that’s unique or unappreciated, don’t bother wasting time on the macro metrics of these diseases, especially when you’re in drug discovery.

Yes indeed, and that goes for anyone who's talking outside the range of their expertise. If you're giving a talk, it should be on something that you know a lot about - more than your audience, right? So why do we have to sit through so many chemists talking about molecular biology, molecular biologists talking about market size, and so on? My rule on that stuff is to hold it down to one slide if possible, and to skip through it lightly even then. I've even seen candidates come in for an interview and spend precious time, time that could be spent showing what they can do and why they should be hired, on telling everyone things that they already know and don't care to hear again.

Comments (24) + TrackBacks (0) | Category: Business and Markets | Drug Development | How To Get a Pharma Job

May 13, 2011

Process Chemistry Makes the Headlines

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Posted by Derek

Not a common occurrence, that. But this Wall Street Journal article goes into details on some efforts to improve the synthetic route to Viread (tenofovir) (or, to be more specific, TDF, the prodrug form of it, which is how it's dosed). This is being funded by former president Bill Clinton's health care foundation:

The chasm between the need for the drugs and the available funding has spurred wide-ranging efforts to bring down the cost of antiretrovirals, from persuading drug makers to share patents of antiretrovirals to conducting trials using lower doses of existing drugs.

Beginning in 2005, the Clinton team saw a possible path in the laboratory to lowering the price of the drugs. Mr. Clinton's foundation had brokered discounts on first-line AIDS drugs, many of which were older and used relatively simple chemistry. Newer drugs, with advantages such as fewer side effects, were more complex and costly to make. . .A particularly difficult step in the manufacture of the antiretroviral drug tenofovir comes near the end. The mixture at that point is "like oatmeal, making it very difficult to stir," explained Prof. Fortunak. That slows the next reaction, a problem because the substance that will become the drug is highly unstable and decomposing, sharply lowering the yield.

Fortunak himself is a former Abbott researcher, now at Howard University. One of his students does seem to have improved that step, thinning out the reaction mixture (which was gunking up with triethylammonium salts) and improving the stability of the compound in it. (Here's the publication on this work, which highlights that step, formation of a phosphate ester, which is greatly enhanced with addition of tetrabutylammonium bromide). This review has more on production of TDF and other antiretrovirals.

This is a pure, 100% real-world process chemistry problem, as the readers here who do it for a living will confirm, and it's very nice to see this kind of work get the publicity that it deserves. People who've never synthesized or (especially) manufactured a drug generally don't realize what a tricky business it can be. The chemistry has to work on large scale (above all!), and do so reproducibly, hitting the mark every time using the least hazardous reagents possible, which have to be reliably sourced at reasonable prices. And physically, the route has to avoid extremes of temperature or pressure, with mixtures that can be stirred, pumped from reactor to reactor, filtered, and purified without recourse to the expensive techniques that those of us in the discovery labs use routinely. Oh, and the whole process has to produce the least objectionable waste stream that you can come up with, too, in case you've got all those other factors worked out already. Not an easy problem, in most cases, and I wish that some of those people who think that drug companies don't do any research of their own would come down and see how it's done.

To give you an example of these problems, the paper on this tenofovir work mentions that the phosphate alkylation seems to work best with magnesium t-butoxide, but that the yield varies from batch to batch, depending on the supplier. And in the workup to that reaction, you can lose product in the cake of magnesium salts that have to be filtered out, a problem that needs attention on scale.

According to the article, an Indian generic company is using the Howard route for tenofovir that's being sold in South Africa. (Tenofovir is not under patent protection in India). Interestingly, two of the big generic outfits (Mylan and Cipla) say that they'd already made their own improvements to the process, but the question of why that didn't bring down the price already is not explored. Did the Clinton foundation improve a published Gilead route that someone else had already fixed? Cipla apparently does the same phosphate alkylation (PDF), but the only patent filing of theirs that I can find that addresses tenofovir production is this one, on its crystalline form. Trade secret?

Comments (21) + TrackBacks (0) | Category: Chemical News | Drug Development | Drug Prices | Infectious Diseases

May 9, 2011

What Medicinal Chemists Really Make

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Posted by Derek

Chemists who don't (or don't yet) work in drug discovery often wonder just what sort of chemistry we do over here. There are a lot of jokes about methyl-ethyl-butyl-futile, which have a bit of an edge to them for people just coming out of a big-deal total synthesis group in academia. They wonder if they're really setting themselves up for a yawn-inducing lab career of Suzuki couplings and amide formation, gradually becoming leery of anything that takes more than three steps to make.

Well, now there's some hard data on that topic. The authors took the combined publication output from their company, Pfizer, and GSK, as published in the Journal of Medicinal Chemistry, Bioorganic Med Chem Letters and Bioorganic and Medicinal Chemistry, starting in 2008. And they analyzed this set for what kinds of reactions were used, how long the synthetic routes were, and what kinds of compounds were produced. Their motivation?

. . .discussions with other chemists have revealed that many of our drug discovery colleagues outside the synthetic community perceive our syntheses to consist of typically six steps, predominantly composed of amine deprotections to facilitate amide formation reactions and Suzuki couplings to produce biaryl derivatives. These “typical” syntheses invariably result in large, flat, achiral derivatives destined for screening cascades. We believed these statements to be misconceptions, or at the very least exaggerations, but noted there was little if any hard evidence in the literature to support our case.

Six steps? You must really want those compounds, eh? At any rate, their data set ended up with about 7300 reactions and about 3600 compounds. And some clear trends showed up. For example, nearly half the reactions involved forming carbon-heteroatom bonds, with half of those (22% of the total) being acylations. mostly amide formation. But only about one tenth of the reactions were C-C bond-forming steps (40% of those were Suzuki-style couplings and 18% were Sonogoshira reactions). One-fifth were protecting group manipulations (almost entirely on COOH and amine groups), and eight per cent were heterocycle formation, and everything else was well down into the single digits.

There are some interesting trends in those other reactions, though. Reduction reactions are much more common than oxidations - the frequency of nitro-to-amine reductions is one factor behind that, followed by other groups down to amines (few of these are typically run in the other direction). Among those oxidations, alcohol-to-aldehyde is the favorite. Outside of changes in reduction state, alcohol-to-halide is the single most favorite functional group transformation, followed by acid to acid chloride, both of which make sense from their reactivity in later steps.

Overall, the single biggest reaction is. . .N-acylation to an amide. So that part of the stereotype is true. At the bottom of the list, with only one reaction apiece, were N-alkylation of an aniline, benzylic/allylic oxidation, and alkene oxidation. Sulfonation, nitration, and the Heck reaction were just barely represented as well.

Analyzing the compounds instead of the reactions, they found that 99% of the compounds contained at least one aromatic ring (with almost 40% showing an aryl-aryl linkage) and over half have an amide, which totals aren't going to do much to dispel the stereotypes, either. The most popular heteroaromatic ring is pyridine, followed by pyrimidine and then the most popular of the five-membered ones, pyrazole. 43% have an aliphatic amine, which I can well believe (in fact, I'm surprised that it's not even higher). Most of those are tertiary amines, and the most-represented of those are pyrrolidines, followed closely by piperazines.

In other functionality, about a third of the compounds have at least one fluorine atom in them, and 30% have an aryl chloride. In contrast to the amides, there are only about 10% of the compounds with sulfonamides. 35% have an aryl ether (mostly methoxy), 10% have an aliphatic alcohol (versus only 5% with a phenol). The least-represented functional groups (of the ones that show up at all!) are carbonate, sulfoxide, alkyl chloride, and aryl nitro, followed by amidines and thiols. There's not a single alkyl bromide or aliphatic nitro in the bunch.

The last part of the paper looks at synthetic complexity. About 3000 of the compounds were part of traceable synthetic schemes, and most of these were 3 and 4 steps long. (The distribution has a pretty long tail, though, going out past 10 steps). Molecular weights tend to peak at between 350 and 550, and clogP peaks at around 3.5 to 5. These all sound pretty plausible to me.

Now that we've got a reasonable med-chem snapshot, though, what does it tell us? I'm going to use a whole different post to go into that, but I think that my take-away was that, for the most part, we have a pretty accurate mental picture of the sorts of compounds we make. But is that a good picture, or not?

Comments (24) + TrackBacks (0) | Category: Chemical News | Drug Development | Life in the Drug Labs | The Scientific Literature

May 5, 2011

Translation Needed

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Posted by Derek

The "Opinionator" blog at the New York Times is trying here, but there's something not quite right. David Bornstein, in fact, gets off on the wrong foot entirely with this opening:

Consider two numbers: 800,000 and 21.

The first is the number of medical research papers that were published in 2008. The second is the number of new drugs that were approved by the Food and Drug Administration last year.

That’s an ocean of research producing treatments by the drop. Indeed, in recent decades, one of the most sobering realities in the field of biomedical research has been the fact that, despite significant increases in funding — as well as extraordinary advances in things like genomics, computerized molecular modeling, and drug screening and synthesization — the number of new treatments for illnesses that make it to market each year has flatlined at historically low levels.

Now, "synthesization" appears to be a new word, and it's not one that we've been waiting for, either. "Synthesis" is what we call it in the labs; I've never heard of synthesization in my life, and hope never to again. That's a minor point, perhaps, but it's an immediate giveaway that this piece is being written by someone who knows nothing about their chosen topic. How far would you keep reading an article that talked about mental health and psychosization? A sermon on the Book of Genesization? Right.

The point about drug approvals being flat is correct, of course, although not exactly news by now, But comparing it to the total number of medical papers published that same year is bizarre. Many of these papers have no bearing on the discovery of drugs, not even potentially. Even if you wanted to make such a comparison, you'd want to run the clock back at least twelve years to find the papers that might have influenced the current crop of drug approvals. All in all, it's a lurching start.

Things pick up a bit when Bornstein starts focusing on the Myelin Repair Foundation as an example of current ways to change drug discovery. (Perhaps it's just because he starts relaying information directly that he's been given?) The MRF is an interesting organization that's obviously working on a very tough problem - having tried to make neurons grow and repair themselves more than once in my career, I can testify that it's most definitely nontrivial. And the article tries to make a big distinction between they way that they're funding research as opposed to the "traditional NIH way".

The primary mechanism for getting funding for biomedical research is to write a grant proposal and submit it to the N.I.H. or a large foundation. Proposals are reviewed by scientists, who decide which ones are most likely to produce novel discoveries. Only a fraction get funded and there is little encouragement for investigators to coordinate research with other laboratories. Discoveries are kept quiet until they are published in peer-reviewed journals, so other scientists learn about them only after a delay of years. In theory, once findings are published, they will be picked up by pharmaceutical companies. In practice, that doesn’t happen nearly as often as it should.

Now we're back to what I'm starting to think of as the "translational research fallacy". I wrote about that here; it's the belief that there are all kinds of great ideas and leads in drug discovery that are sitting on the shelf, because no one in the industry has bothered to take a look. And while it's true that some things do slip past, I'm really not sure that I can buy into this whole worldview. My belief is that many of these things are not as immediately actionable as their academic discoverers believe them to be, for one thing. (And as for the ones that clearly are, those are worth starting a company around, right?) There's also the problem that not all of these discoveries can even be reproduced.

Bornstein's article does get it right about this topic, though:

What’s missing? For a discovery to reach the threshold where a pharmaceutical company will move it forward what’s needed is called “translational” research — research that validates targets and reduces the risk. This involves things like replicating and standardizing studies, testing chemicals (potentially millions) against targets, and if something produces a desired reaction, modifying compounds or varying concentration levels to balance efficacy and safety (usually in rats). It is repetitive, time consuming work — often described as “grunt work.” It’s vital for developing cures, but it’s not the kind of research that will advance the career of a young scientist in a university setting.

“Pure science is what you’re rewarded for,” notes Dr. Barres. “That’s what you get promoted for. That’s what they give the Nobel Prizes for. And yet developing a drug is a hundred times harder than getting a Nobel Prize. . .

That kind of research is what a lot of us spend all our days doing, and there's plenty of work to fill them. As for developing a drug being harder than getting a Nobel Prize, well, apples and oranges, but there's something to it, still. The drug will cost you a lot more money along the way, but with the potential of making a lot more at the end. Bornstein's article goes off the rails again, though, when he says that companies are reluctant to go into this kind of work when someone else owns the IP rights. That's technically true, but overall, the Bayh-Dole Act on commercialization of academic research (despite complications) has brought many more discoveries to light than it's hindered, I'd say. And he's also off base about how this is the reason that drug companies make "me too" compounds. No, it's not because we don't have enough ideas to work on, unfortunately. It's because most of them (and more over the years) don't go anywhere.

Bornstein's going to do a follow-up piece focusing more on the Myelin Repair people, so I'll revisit the topic then. What I'm seeing so far is an earnest, well-meaning attempt to figure out what's going on with drug discovery - but it's not a topic that admits of many easy answers. That's a problem for journalists, and a problem for those of us who do it, too.

Comments (26) + TrackBacks (0) | Category: "Me Too" Drugs | Academia (vs. Industry) | Drug Development | Who Discovers and Why

April 27, 2011

Off the Beaten Track. Way, Way, Off.

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Posted by Derek

Now here's a structure that you don't see every day. A company called RadioRx is developing compounds as radiotherapy sensitizers for oncology, designed to release reactive free radicals and intensify the cell-killing effects of ionizing radiation. And these compounds are not from the usual sources. As they put it:

In collaboration with a major defense contractor, RadioRx is developing its first lead candidate, RRx-001, a best-in-class small molecule, adapted from an energetic solid rocket propellant. The development candidate is scheduled to enter first-in-man phase 1 clinical studies by Q1 2011.

I've been forwarded a report that this is the structure of their compound, which would make their defense-contractor partner Thiokol (the assignee where that compound appears in the patent literature). (Here's one of RadioRx's own patents in this area). And I truly have to salute these guys for going forward with such an out-there structure. Can anyone doubt that this is the first gem-dinitroazetidine to reach the clinic? And with a bromoamide on the other end of it, yet?
dinitro.png
It's easy to look at something like this and mutter "Only in oncology", but at the same time, it takes some nerve and imagination to go forward with compounds this odd. I hope that they work - and I hope that everyone else looks at their own chemical matter and decides that hey, maybe there's more to life than Suzuki couplings and benzo-fused heterocycles.

Comments (27) + TrackBacks (0) | Category: Cancer | Drug Development

April 11, 2011

R&D Is For Losers?

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Posted by Derek

Now here's a piece that I'm looking for good reasons to dismiss. And I think its author, Jim Edwards, wouldn't mind some, too. You've probably heard that Valeant Pharmaceuticals is making a hostile offer for Cephalon, a company that's dealing with some pipeline/patent problems (and, not insignificantly, the recent death of their founder and CEO).

Valeant's CEO, very much alive, is making no secret of his business plan for Cephalon should he prevail: ditch R&D as quickly as possible:

“His approach isn’t one that most executives in the drug business take,” (analyst Timothy) Chiang said in telephone interview last week. “He’s even said in past presentations: ‘We’re not into high science R&D; we’re into making money.’ I think that’s why Valeant sort of trades in a league of its own.”

. . .Pearson’s strategy and viewpoint on research costs have been consistent. When he combined Valeant with drugmaker Biovail Corp. in September, he cut about 25 percent of the workforce, sliced research spending and established a performance-based pay model tied to Valeant’s market value.

“I recognize that many of you did not sign up for either this strategy or operating philosophy,” Pearson wrote in a letter to staff at the time. “Many of you may choose not to continue to work for the new Valeant.”

Valeant does, in fact, make plenty of money. But my first thought (and the first thought of many of you, no doubt) is that it's making money because other people are willing to do the R&D that they themselves are taking a pass on. In other words, there's room for a few Valeants in the industry, but you couldn't run the whole thing that way, because pretty soon there'd be nothing for those whip-cracking revenue-maximizing managers to sell. Would there?

But we don't have to go quite that far. Edwards, for his part, goes on to wonder (as many have) whether the drug industry should settle out into two groups: the people that do the R&D and the people that sell the drugs. This idea has been proposed as a matter of explicit government policy (a nonstarter), but short of that, has been kicked around many times. Most of the time, this scheme involves smaller companies doing the research, with the big ones turning into the regulatory/sales engines, but maybe not:

If you agree that there ought to be a division of labor in the pharma business — that some companies should develop drugs and then sell those products to the companies that have the salesforces to market them — then this says some interesting things about recent corporate strategy moves among the largest companies. Pfizer (PFE) is downsizing its R&D operations and Johnson & Johnson (JNJ) is said to be on the prowl for a ~$10 billion acquisition.

Merck, on the other hand, is doubling down on its own research and stopped giving Wall Street guidance in hopes of lessening the scrutiny paid to its R&D expense base.

.

The heralds of this restructuring of the industry haven't quite called it this way, but instead splitting from each other, perhaps the big companies will divide into two camps (Merck vs. Pfizer) and the smaller ones, too (Valeant vs. your typical small pharma). Prophecy's not an exact science - Marx thought that Germany and England would be the first countries to go Communist, you know.

For my part, I think that there are game-theory reasons why a big company won't explicitly renounce R&D. As it is, a big company can signal that "Yes, we'd like to do a deal for your drug (or your whole company), but you know, there are other things for us to do with the money if this doesn't work out." But if you're only inlicensing, then no, there aren't so many other things for you to do with the money. Everyone else can look around the industry and see what's available for you to buy, and thus the price of your deals goes up. You have no hidden cards from your internal R&D to play (or to at least pretend like you're holding). This signaling, by the way, is directed to the current and potential shareholders as well: "Buy our stock, because you never know what our brilliant people are going to come up with next". That's a more interesting come-on line than "Buy our stock. You never know who we're going to buy next." Isn't it?

And that's a separate question from the even bigger one of whether there are enough compounds out there to inlicense in the first place. No, I think that big companies will hold onto their own R&D in one form or another. But we'll see who's right.

Comments (47) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

March 31, 2011

Your Comments on the NIH's CNS Drug Program?

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Posted by Derek

After my post the other day on the NIH neurological disease effort, I heard from Rebecca Farkas there, who's leading the medicinal chemistry effort on the program. She's glad to get feedback from people in the industry, and in fact is inviting questions and comments on the whole program. Contact her at farkasr-at-ninds-dot-nih-dotgov (perhaps putting the address in that form will give the spam filters at NIH a bit less to do than otherwise).

She also sends word that they'll be advertising soon for a Project Manager position for this effort, and is looking for suggestions on how to reach the right audience for a good selection of candidates. This post might help a bit, but she's interesting in suggestions on where to advertise and who to contact for good leads.

Comments (2) + TrackBacks (0) | Category: Drug Development | The Central Nervous System

March 29, 2011

The NIH Goes For the Gusto

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Posted by Derek

Here's an interesting funding opportunity from NIH:

Recent advances in neuroscience offer unprecedented opportunities to discover new treatments for nervous system disorders. However, most promising compounds identified through basic research are not sufficiently drug-like for human testing. Before a new chemical entity can be tested in a clinical setting, it must undergo a process of chemical optimization to improve potency, selectivity, and drug-likeness, followed by pre-clinical safety testing to meet the standards set by the Food and Drug Administration (FDA) for clinical testing. These activities are largely the domain of the pharmaceutical industry and contract research organizations, and the necessary expertise and resources are not commonly available to academic researchers.

To enable drug development by the neuroscience community, the NIH Blueprint for Neuroscience Research is establishing a ‘virtual pharma’ network of contract service providers and consultants with extensive industry experience. This Funding Opportunity Announcement (FOA) is soliciting applications for U01 cooperative agreement awards from investigators with small molecule compounds that could be developed into clinical candidates within this network. This program intends to develop drugs from medicinal chemistry optimization through Phase I clinical testing and facilitate industry partnerships for their subsequent development. By initiating development of up to 20 new small-molecule compounds over two years (seven projects were launched in 2011), we anticipate that approximately four compounds will enter Phase 1 clinical trials within this program.

My first thought is that I'd like to e-mail that first paragraph to Marcia Angell and to all the people who keep telling me that NIH discovers most of the drugs on the market. (And as crazy as that sounds, I still keep running into people who are convinced that that's one of those established facts that Everyone Knows). My second thought is that this is worth doing, especially for targeting small or unusual diseases. There could well be interesting chemical matter or assay ideas floating around out there, looking for the proper environment to have something made of them.

My third thought, though, is that this could well end up being a real education for some of the participants. Four Phase I compounds out of twenty development candidates - it's hard to say if that's optimistic or not, because the criteria for something to be considered a development candidate can be slippery. And that goes for the drug industry too, I hasten to add. Different organizations have different ideas about what kinds of compounds are worth taking to the clinic, and those criteria vary by disease area, too. (Sad to say, they can also vary by time of the year and the degree to which bonuses are tied to hitting number-of-clinical-candidate goals, and anyone who's been around the business a while will have seen that happen, to their regret).

It'll be interesting to see how many people apply for this; the criteria look pretty steep to me:

Applicants must have available small-molecule compounds with strong evidence of disease-related activity and the potential for optimization through iterative medicinal chemistry. Applicants must also be able to conduct bioactivity and efficacy testing to assess compounds synthesized in the development process and provide all pre-clinical validation for the desired disease indication. . .This initiative is not intended to support development of new bioactivity assays, thus the applicant must have in hand well-characterized assays and models.

Hey, there are small companies out there that don't come up to that standard. To clarify, though, the document does say that "Evaluation of the approach should focus primarily on the rationale and strengths/weaknesses of proposed bioactivity studies and compound "druggability," since all other drug development work (e.g., medicinal chemistry, PK/tox, phase I clinical testing) will be designed and implemented by NIH-provided consultants and contractors after award", which must come as something of a relief.

What's interesting to me, though, is that the earlier version of this RFA (from lsat year) had the following language:

The ultimate goals of this Neurotherapeutics Grand Challenge are to produce at least one novel and effective drug for a nervous system disorder that is currently poorly treated and to catalyze industry interest in novel disease targets by demonstrating early-stage success.

That's missing this time around, which is a good thing. If they're really hoping for a drug to come out of four Phase I candidates in poorly-treated CNS disorders, then I'd advise them to keep that thought well hidden. The overall attrition rate in the clinic in CNS is somewhere around (and maybe north of) 90%, and if you're going to go after the tough end of that field it's going to be even steeper.

Comments (7) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Development | The Central Nervous System

March 28, 2011

Value in Structure?

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Posted by Derek

A friend on the computational/structural side of the business sent along this article from Nature Reviews Drug Discovery. The authors are looking through the Thomson database at drug targets that are the subject of active research in the industry, and comparing the ones that have structural information available to the ones that don't: enzyme targets (with high-resolution structures) and and GPCRs without it. They're trying to to see if structural data is worth enough to show up in the success rates (and thus the valuations) of the resulting projects.

Overall, the Thomson database has over a thousand projects in it from these two groups, a bit over 600 from the structure-enabled enzymes and just under 500 GPCR projects. What they found was that 70% of the projects in the GPCR category were listed as "suspended" or "discontinued", but only 44% of the enzyme projects were so listed. In order to correct for probability of success across different targets, the authors picked ten targets from each group that have led, overall, to similar numbers of launched drugs. Looking at the progress of the two groups, the structure-enabled projects are again lower in the "stopped" categories, with corresponding increases in discovery and the various clinical phases.

You have to go to the supplementary info for the targets themselves, but here they are: for the enzymes, it's DPP-IV, BCR-ABL, HER2 kinase, renin, Factor Xa, HDAC, HIV integrase, JAK2, Hep C protease, and cathepsin K. For the receptor projects, the list is endothelin A receptor, P2Y12, CXCR4, angiogensin II receptor, sphingosine-1-phosphate receptor, NK1, muscarinic M1, vasopressin V2, melatonin receptor, and adenosine A2A.

Looking over these, though, I think that the situation is more complicated than the authors have presented. For example, DPP-IV has good structural information now, but that's not how people got into the area. The cyanopyrrolidine class of inhibitors, which really jump-started the field, were made by analogy to a reported class of prolyl endopeptidase inhibitors (BOMCL 1996, p. 1163). Three years later, the most well-characterized Novartis compound in the series was being studied by classic enzymology techniques, because it still wasn't possible to say just how it was binding. But even more to the point, this is a well-trodden area now. Any DPP-IV project that's going on now is piggybacking not only on structural information, but on an awful lot of known SAR and toxicology.

And look at renin. That's been a target forever, structure or not. And it's safe to say that it wasn't lack of structural information that was holding the area back, nor was it the presence of it that got a compound finally through the clinic. You can say the same things about Factor Xa. The target was validated by naturally occurring peptides, and developed in various series by classical SAR. The X-ray structure of one of the first solid drug candidates in the area (rivaroxaban) bound to its target, came after the compound had been identified and the SAR had been optimized. Factor Xa efforts going on now also are standing on the shoulders of an awful lot of work.

In the case of histone deacetylase, the first launched drug in that category (SAHA, vorinostat) has already been identified before any sort of X-ray structure was available. Overall, that target is an interesting addition to the list, since there are actually a whole series of them, some of which have structural information and some of which don't. The big difficulty in that area is that we don't really know what the various roles of the different isoforms are, and thus how the profiles of different compounds might translate to the clinic, so I wouldn't say that structural data is helping with the rate-determining steps in the field.

On the receptor side, I also wouldn't say that it's lack of structural information that's necessarily holding things back in all of those cases, either. Take muscarinic M1 - muscarinic ligands have been known for a zillion years. That encompasses fairly selective antagonists, and hardly-selective-at-all agonists, so I'm not sure which class the authors intended. If they're talking about antagonists, then there are plenty already known. And if they're talking about agonists, I doubt that even detailed structural information would help, given the size of the native ligand (acetylcholine).

And the vasopressin V2 case is similar to some of the enzyme ones, in that there's already an approved drug in this category (tolvaptan), with several others in the same structural class chasing it. Then you have the adenosine A2A field, where long lists of agonists and antagonists have been found over the years, structure or not. The problem there has been finding a clinical use for them; all sorts of indications have been chased over the years, a problem that structural information would have not helped with in the least.

Now, it's true that there are projects in these categories where structure has helped out quite a bit, and it's also true that detailed GPCR structures would be welcome (and are slowly coming along, for that matter). I'm not denying either of those. But what does strike me is that there are so many confounding variables in this particular comparison, especially among the specific targets that are the subject of the article's featured graphic, that I just don't think that its conclusions follow.

Comments (32) + TrackBacks (0) | Category: Drug Development | Drug Industry History | In Silico

March 24, 2011

More on KV and Makena's Pricing

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Posted by Derek

I wanted to do some follow-up on the Makena story - the longtime progesterone ester drug that has now been newly FDA-approved and newly made two order of magnitude more expensive. (That earlier post has the details, for those who might not have been following).

Steve Usdin at BioCentury has, in the newsletter's March 21st issue, gone into some more detail about the whole process where KV Pharmaceuticals stepped in under the Orphan Drug Act to pick up exclusive marketing rights to the drug. The company, he says, "arguably has played a marginal role" in getting the drug back onto the market.

Here's the timeline, from that article and some digging around of my own: in 1956, Squibb got FDA approval for the exact compound (progesterone caproate) for the exact indication (preventing preterm labor), under the brand name Delalutin. But at that time, the FDA didn't require proof of efficacy, just safety. There were several small, inconclusive academic studies during the 1960s. In 1971, the FDA noted that the drug was effective for abnormal uterine bleeding and other indications, and was "probably effective" for preventing preterm delivery. In 1973, though, based on further data from the company, the agency went back on that statement, and said that there was now evidence of birth defects from the use of Delalutin in pregnant women, and removed any of these as approved uses. In the late 1970s, warning language was further added. In 1989, the agency said that its earlier concerns (heart and limb defects) were unfounded, but warned of others. By 1999, the FDA had concluded that progesterone drugs were too varied in their effects to be covered under a single set of warnings, and took the warning labels off.

In 1998, the National Institute of Child Health and Human Development launched a larger, controlled study, but this was an example of bad coordination all the way. By this time, Bristol-Myers Squibb had requested that Delalutin's NDAs be revoked, saying that they hadn't even sold the compound for several years. This seems to have also been a move, though, in response to FDA complaints about earlier violations of manufacturing guidelines and a request to recall the outstanding stocks of the drug. So the NICHD study was terminated after a year, with no results, and the drug's NDA was revoked as of September, 2000.

The NICHD had started another study by then, however, although I'm not sure how they solved their supply problems. This is the one that reported data in 2003, and showed a real statistical benefit for preterm labor. More physicians began to prescribe the drug, and in 2008, the American College of Obstetricians and Gynecologists recommended its use.

So much for the medical efficacy side of the story. Now we get back to the regulatory and marketing end of things. In March of 2006, a company called CUSTOpharm asked the FDA to determine if the drug had been withdrawn for reasons of safety or efficacy - basically, was it something that could be resubmitted as an ANDA? The agency determined that the compound was so eligible.

Meanwhile, another company called Adeza Biomedical was moving in the same direction (as far as I can tell, they and CUSTOpharm had nothing to do with each other, but I don't have all the details). Adeza submitted an NDA in July 2006, under the FDA's provision for using data that that applicant had not generated - in fact, they used the NICHD study results. They called the compound Gestiva, and asked for accelerated approval, since preterm delivery was accepted as a surrogate for infant mortality. An advisory committee recommended this in August of 2006, by a 12 to 9 vote. (Scroll down to the bottom of this page for the details).

The agency sent Adeza an "approvable" letter in October 2006 which asked for more animal studies. The next year, Adeza was bought by Cytec, who were bought by Hologic, who sold the Gestiva rights to KV Pharmaceuticals in January 2008. So that's how KV enters the story: they bought the drug program from someone who bought it from someone who just used a government agency's clinical data.

The NDA was approved by the FDA in February 2011, along with a name change to Makena. By this time, KV and Hologic had modified their agreement - KV had already paid up nearly $80 million, with another $12.5 million due with the approval, and has further payments to make to Hologic which would take the total purchase price up to nearly $200 million. That's been their main expense for the drug, by far. The FDA has asked them to continue two ongoing studies of Makena - one placebo-controlled trial to look at neonatal mortality and morbidity, and one observational study to see if there are any later developmental effects. Those studies will report in late 2016, and KV has said that their costs will be in the "tens of millions". So they paid more for the rights to Makena than it's costing them to get it studied in the clinic.

That only makes sense if they can charge a lot more than the generic price for the drug had been, of course, and that's what takes us up to today, with the uproar over the company's proposed price tag of $1500 per treatment. But the St. Louis Post-Dispatch (thanks to FiercePharma for the link) says that the company has now filed its latest 10-Q with the SEC, and is notifying investors that its pricing plans are in doubt:

The success of the Company’s commercialization of Makena™ is dependent upon a number of factors, including: (i) the Company’s ability to maintain certain net pricing levels for Makena™; (ii) successfully obtaining agreements for coverage and reimbursement rates on behalf of patients and medical practitioners prescribing Makena™ with third-party payors, including government authorities, private health insurers and other organizations, such as HMOs, insurance companies, and Medicaid programs and administrators, and (iii) the extent to which pharmaceutical compounders continue to produce non-FDA approved purported substitute product. The Company has been criticized regarding the list pricing of Makena™ in a number of news articles and internet postings. In addition, the Company has received, and expects to continue to receive, letters criticizing the Company’s list pricing of Makena™ from several medical practitioners and several advocacy groups, including the March of Dimes, American College of Obstetricians and Gynecologists, American Academy of Pediatrics and the Society for Maternal Fetal Medicine. Further, the Company has received one letter from a United States Senator and expect to receive another letter from a number of members of the United States Congress asking the Company to reduce its indicated pricing of Makena™, and the same Senator, together with a second Senator, has sent a letter to the Federal Trade Commission asking the agency to initiate an investigation of our pricing of Makena™.

The Company is responding to these criticisms and events in a number of respects. . .The success of the Company is largely dependent upon these efforts and appropriately responding to both the media and governmental concerns regarding the pricing of Makena™.

Personally, I'm torn a bit by the whole situation. I think that people and companies have the right to charge what the market will bear for their goods and services. But at the same time, I find myself also very irritated by KV in this case, because I truly think that they are taking advantage of the regulatory framework. As I said in the last post, it's not like they took on much risk here - they didn't discover this drug, didn't do the key clinical work on it, and don't even manufacture it themselves. Their business plan involves sitting back and collecting the rent, but that's what the law allows them to do.

In the end, if political pressure forces them to back down on their pricing, this will come down to a poor business decision. Companies should, in fact, charge what the market will bear - but KV may have neglected some other factors when they calculated what that price should be. Before setting a price, you should ask "Will the insurance companies pay?" and "Will Medicare pay?" and "Will people pay out of their own pocket?", but you should also ask "Will this price bring down so much controversy that we won't be able to make it stick?"

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March 11, 2011

Makena's Price: What to Do?

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Posted by Derek

The situation with KV Pharmaceuticals and the premature birth therapy Makena has been all over the news in the last couple of days. Briefly, Makena is an injectable progesterone formulation, given to women at risk of delivering prematurely. It went off the market in the early 1990s, because of side effect concerns and worries about overall efficacy, but since 2003 it's made an off-label comeback, thanks largely to a study at Wake Forest. This seemed to tip the risk/benefit ratio over to the favorable side.

Comes now the FDA and the provisions for orphan drugs. There is an official program offering market exclusivity to companies that are willing to take up such non-approved therapies and give them the full clinical and regulatory treatment. The idea, which is well-intentioned, as so many ideas are, was to bring these things in from the cold and give them more medical, scientific, and legal standing as things that had been through the whole review process. And that's what KV did. But this system says nothing about what the price of the drug will be during the years of exclusivity, in the same way that the approval process for new drugs says nothing about what their price will be when they come to market.

KV has decided that the price will now be about $1500 per patient, as opposed to about $15 before under the off-label regime. The reaction has been exactly what one would expect, and why not? Here, then are some thoughts:

Unfortunately, this should not have come as a surprise. It seems to have, though. The news stories are full of quotes from patients, doctors, and insurance companies saying that they never saw this coming. Look, though, at what happened recently with colchicine. Same situation. Same price jump. Same outrage, understandably. As long as these same incentives exist, any no-name generic company that comes along to adopt an old therapy and bring it into the modern regulatory regime can be assumed to be planning to run the price up to what they think the market will bear. That's why they're going to the trouble.

KV seems to have guessed correctly about the price. You wouldn't think so, with a hundred-fold increase. And the news stories, as I say, are full of (understandably) angry quotes from people at the insurance companies who will now be asked to pay. But (as that NPR link in the first paragraph says), Aetna, outraged or not, is going to pony up. It's going to cost them $20 to $30 million per year, most of which is going to go directly to KV's bottom line, but they're going to pay. And the other big health insurance providers seem to be doing the same. Meanwhile, the company has announced a program to provide low-cost treatment to people without insurance. From what I can see, it looks like basically everyone who had access to the drug before will have it now, the main difference being that the payers with deeper pockets will now be getting hammered on by KV. This is not a nice way to run a business, and it's not something I would sleep well on after having done myself. But there it is.

How much is regulatory approval worth, anyway? That seems to be what we're really arguing about. After all, patients are getting the same drug, in the same formulation, dosed the same way as before. But now it's **FDA Approved**. For new substances, I think regulatory approval is worth quite a bit. There are all kinds of things that can go wrong. But how about drugs that have been dosed in humans for years? And already run through the equivalent of Phase II trials by other people? The main thing that's being added is some confirmation that yes, the dose that everyone's been using is about right, and yes, the effects that are being seen are, in fact, real. And that's not worthless, not at all - but how much is it worth, really? The agency itself seems to place a pretty high value on it - seven years of market exclusivity, to be exact, and we can see by example just what that goes for on the market.

This does the drug industry no good, either. We have a bad enough reputation as it is, wouldn't you think? What's irritating, to someone like me who works at a "find a new drug" type of company, is that these no-name generic outfits (KV in this case, URL Pharma for colchicine) are doing pretty much what critics of the industry think that we all do, all the time. That is, walk up to situations where other people have done a lot of the work, a good amount of it with public/NIH money, and step right in and profit. Now it's true that these companies have to basically run Phase II/Phase III trials to take the data to the FDA, and that's a significant amount of money. But their risks in doing so have been watered down immensely by the history of these drugs in the medical community. When a research company closes its eyes, holds its breath, and jumps into the clinic with a new molecule, that's one thing. And that's where those 90% failure rates come from. But the failure rate of drugs that have been used for years in human patients already, and already studied under clinical conditions, is not anything like 90%. Is it zero per cent? Has anyone failed yet, taking one of these old medications back to the FDA? Even once?

The company picked its target carefully. I will say this, that KV's trials have presumably clarified the question of whether progesterone therapy actually does help. You'd think that the 2003 study would have answered that, and as it turned out, it had. A review of the field in 2006 concluded that it was a worthwhile therapy, from a cost/benefit standpoint, as did another review in 2007. (Mind you, that wasn't at any $1500 a throw, was it?) But a Cochrane review from last year concluded that there still wasn't enough evidence to recommend the whole idea. And progesterone therapy doesn't seem to help with twin or tripletpregnancies or with some other gestational problems. No, the 2003 study seemed fairly strong, and has the greatest relevance to public health, so that's what the company went for. From one viewing angle, the system worked.

My take, though, is that as long as the regulatory environment is set to value FDA's stamp of approval for old drugs this highly, that people will continue to take advantage of it. You subsidize something; you're going to get it. Personally, I don't think that the balance is right, but I'm open to suggestion about what to do about it. A shorter period of market exclusivity would just mean, I think, that the prices go up even higher once a drug gets re-approved. Just throwing up our hands and letting all that old stuff stand is a possibility, but there may well still be some of these things that aren't as effective as we think, or aren't being dosed right, and we have to decide what the cost is of letting those situations stand.

Update: see also Alex Tabarrok's thoughts on the effects of the Orphan Drug Act in general.

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March 10, 2011

The Cost to Develop a Drug: Your Own Numbers?

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Posted by Derek

Bruce Booth over at Atlas Venture (a VC fund here in Cambridge) has been following the Light and Warburton drug-cost estimate with interest. And now he's got a form up on his site for people to enter their own estimates of the costs. Take a look - it's bound to come up with a number that's more in tune with reality! For one thing, he's actually asking people who have, you know, developed drugs. . .

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March 8, 2011

That $43 Million R&D Figure

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Posted by Derek

One of the readers in the comments section to the last post noticed Rebecca Warburton trying to clarify that absurd $43-million-per-drug R&D figure. You'll find her response in the comments section to the Slate piece that brought this whole study so much attention. Says Warburton:

. . .Our estimate of $59 million is the median development (the “D” in R&D) cost per average drug, not just NMEs (new chemicals) and does not include basic research costs, for which there is no reasonable estimate available.

But that explanation won't wash, as some of the readers over at Slate noticed as well. If you read the Light and Warburton article itself, you find the authors talking about nothing but "R&D" all the way through. In the one section where they do start to make a distinction, they brush aside expenses for basic research, on the grounds that drug companies hardly do any:

Companies under pressure from quarterly reports have difficulty justifying long searches for breakthrough drugs to investors. . .Little company R&D is devoted to basic research. Although industry association reports, based on unverified numbers from its members, claim that companies invest on average 17–19 per cent of sales in R&D, the most authoritative data come from the long-standing survey by the US National Science Foundation (2003). Its data document that pharmaceutical firms invest 12.4 per cent of gross domestic sales on R&D. Of this, 18 per cent, or 2.4 per cent of sales, went to basic research. More detailed reports from the industry indicate the percentage of R&D going to basic research is even smaller, about 9.3 per cent (or 1.2 per cent of sales) (Light, 2006). Thus the net corporate investment in research to discover important new drugs is about 1.2 per cent of sales, not 17–19 per cent.

So no, claiming that the $43 million figure is only supposed to represent the "D" part of R&D is disingenuous. There's another line from this paper, quoting Marcia Angell, that I think gets to one of the roots of the problem with the way these authors have characterized drug research. Angell is quoted here with approval - everything she and Merril Goozner have to say is quoted with approval:

It is also unclear how far back one should go to count up the costs of discovery, given that often there are several strands of research that are pieced together. In Angell’s view, the critical step in ‘discovering’ a new drug is understanding how the disease works and finding one or two good targets of vulnerability in the defences of a disease for intervention. Basic research ‘is almost always carried out at universities or government research labs, either in this country or abroad’ (Angell, 2004, p. 23).

And there you have it. The critical step is understanding how the disease works, you see, and finding one or two good targets. By that definition, the vast amount of money that gets spent in the drug industry is then non-critical. This is a viewpoint that can only be held by someone who has never tried to discover a drug, or never held a serious conversation with anyone who has.

Let's poke a few holes in that worldview. First off, if we waited to "understand" diseases before trying to develop drugs for them, we'd hardly have a damned thing on the drugstore shelves. Look at Alzheimer's - the medical community is still having fist-waving arguments about its cause, while drug companies continue to sink piles of money into trying to treat it. (Almost all of which has gone down the tubes, I might add, and I helped flush some of it through myself, earlier in my career).

Then you have to find one or two good targets. Peachy! Where do you find those thingies, anyway? And how do you know that they're good targets? I wish that Marcia Angell, Donald Light, or Rebecca Warburton would let the rest of us in on those secrets. As it is, we have to take chances on some pretty tenuous stuff, and often the only way to find out if a target really has any connection to human health is to. . .well, to discover a drug candidate that hits it. And develop it, and get it through tox, and into humans, and through Phase I, and into Phase II, and more likely than not these days, into Phase III before you really find out if, you know, it was actually a good target. We pass on those results to the rest of the world at that point. But that doesn't count as research, apparently.

And how about the drugs that have been developed without good mechanisms or targets at all? Metformin, ezetimibe, rosiglitazone and pioglitazone: none of these had any detailed mechanisms worked out for them while the money was being spent to develop them. These are the sorts of things we do around here in between having meetings to decide what color the package should be, and right after we do that thing where we all jump around in rooms knee-deep in hundred-dollar bills. Exhausting stuff, that money-wading.

But what I'd really like to ask Light and Warburton about is this: if you do think that the Tufts/diMasi estimate is crap, why did you feel as if the antidote was more crap from the opposite direction? Honestly, I'd think that intelligent people of good will might be more interested in decreasing the total amount of crap out there instead. . .

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March 7, 2011

The Costs of Drug Research: Beginning a Rebuttal

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Posted by Derek

Note: a follow-up post to this one can be found here.

I've had a deluge of emails asking me about this article from Slate on the costs of drug research. It's based on this recent publication from Donald Light and Rebecca Warburton in the London School of Economics journal Biosocieties, and it's well worth discussing.

But let's get a few things out of the way first. The paper is a case for the prosecution, not a dispassionate analysis. The authors have a great deal of contempt for the pharmaceutical industry, and are unwilling (or unable) to keep it from seeping into their prose. I'm tempted to reply in kind, but I'm supposed to be the scientist in this discussion. We'll see how well I manage.

Another thing to mention immediately is that this paper is, in fact, not at all worthless. In between the editorializing, they make some serious points, and most of these are about the 2003 Tufts (diMasi) estimate of drug development costs. This is the widely-cited $802 million figure, and the fact that it's widely cited is what seems to infuriate the authors of this paper the most.

Here are their problems with it: the Tufts study surveyed 24 large drug companies, of which 10 agreed to participate. (In other words, this is neither a random nor a comprehensive sample). The drugs used for the study numbers were supposed to be "self-originated", but since we don't know which drugs they were, it's impossible to check this. And since the companies reported their own numbers, these would be difficult to check, even if they were made available drug-by-drug (which they aren't). Nor can anyone be sure that variations in how companies assign costs to R&D haven't skewed the data as well. We may well be looking at the most expensive drugs of the whole sample; it's impossible to say.

All of these are legitimate objections - the Tufts numbers are just not transparent. Companies are not willing to completely spread their books out for outside observers, in any industry, so any of these estimates are going to be fuzzy. Light and Warburton go on to some accounting issues, specifically the cost-of-capital estimate that took their estimated cost for a new drug from 400 million to 800 million. That topic has been debated around this blog before, and it's important to break that argument into two parts.

The first one is whether it's appropriate to consider opportunity costs at all. I still say that it is, and I don't have much patience for the "argument from unfamiliarity". If you commit to some multi-year use of your money, you really are forgoing what you could have earned with it otherwise. You're giving it up - it's a cost, whether you're used to thinking of it that way or not. But the second part of the argument is, just how much could you have earned? The problem here is that the Tufts study assumes 11% returns, which is just not anywhere near realistic. Mind you, it's on the same order of fantasy as the returns that have been assumed in the past inside many pension plans, but we're going to be dealing with that problem for years to come, too. No, the Tufts opportunity cost numbers are just too high.

Then there's the tax situation. I am, I'm very happy to say, no expert on R&D tax accounting. But it's enough to say that there's arguing room about the effects of the various special tax provisions for expenditures in this area. And it's complicated greatly by different treatment in different part of the US and the world. The Tufts study does not reduce the gross costs of R&D by tax savings, while Light and Warburton argue otherwise. Among other points, they argue that the industry is trying to have it both ways - that cost-of-capital arguments make R&D expenditures look like a long-term investment, while for tax purposes, many of these are deductible each year as more of an ordinary business expense.

Fine, then - I'm in agreement, on general principles, with Light and Warburton when they say that the Tufts study estimates are hard to check and likely too high. But here's where we part company. Not content to make this point, the authors turn around and attempt to replace one shaky number with another. The latter part of their paper, to me, is one one attempt after another to push their own estimate of drug R&D costs into a world of fantasy. Their claim is that the median R&D cost for a new drug is about $43 million. This figure is wrong.

For example, they have total clinical trial and regulatory review time dropping (taken from this reference - note that Light and diMasi, lead author of the Tufts study, are already fighting it out in the letter section). But if that's true why isn't the total time from discovery to approval going down? I've been unable to find any evidence that it is, and my own experience certainly doesn't make me think that the process is going any faster.

The authors also claim that corporate R&D risks are much lower than reported. Here they indulge in some rhetoric that makes me wonder if they understand the process at all:

Reports by industry routinely claim that companies must test 5000-10000 compounds to discover one drug that eventually comes to market. Marcia Angell (2004) points out that these figures are mythic: they could say 20,000 and it would not matter much, because the initial high-speed computer screenings consume a small per cent of R&D costs. . .

The truth is, even a screen of 20,000 compounds is tiny. And those are real, physical, compounds, not "computer screenings". It's true, though, that high-throughput screening is a small part of R&D costs. But the authors are mixing up screening and the synthesis of new compounds. We don't find our drug candidates in the screening deck - at least, not in any project I've worked on since 1989. We find leads there, and then people like me make all kinds of new structures - in flasks, dang it, not on computers - and we test those. Here, read this.

The authors go on to say:

Many products that 'fail' would be more accurately described as 'withdrawn', usually because trial results are mixed; or because a company estimates that the drug will not meet their high sales threshold for sufficient profitability. The difference between 'failure' and 'withdrawal' is important, because many observers suspect that companies withdraw or abandon therapeutically important drugs for commercial reasons. . .

Bring out some of those observers, then! And bring on the list of therapeutically important drugs that have been dropped out of the clinic just for commercial reasons. Please, give us some examples to work with here, and tell me how the disappointing data that the companies reported at the time (missed endpoints, tox problems) were fudged. Now, I have seen a compound fall out of actual production because of commercial reasons (Pfizer's Exubera), but that was partly because it didn't turn out to be as therapeutically important as the company convinced itself that it would be.

And here's another part I especially like:

Company financial risk is not only much lower than usually conveyed by the '1 in 5000' rhetoric, but companies spread their risks over a number of projects. The larger companies are, and the more they merge with or buy up other companies, the less risk they bear for any one R&D project. The corporate risk of R&D for companies like Pfizer or GlaxoSmithKinen are thus lower than for companies like Intel that have only a few innovations on which sales rely.

Well, then. That means that Pfizer, as the biggest and most-merged-up drug company in the world, must have minimized its risk more than anyone in the industry. Right? And they should be doing just fine by that? Not laying people off right and left? Not closing any huge research sites? Not wondering frantically how they're going to replace the lost revenue from Lipitor? Not telling people that they're actually ditching several therapeutic areas completely because they don't think than can compete in them, given the risks? Not announcing a stock buyback program, because they apparently (and rather shamefully) think that's a better use of their money than putting it back into more R&D? I mean, how can Intel be doing better than that? It's almost like chip design is a different sort of R&D business entirely.

Well, this post is already too long, and there's more to discuss in another one, at least. But I wanted to add one more argument from economic reality, an extension of those little questions about Pfizer. If the cost of R&D for a new drug really were $43 million, as Light and Warburton would have it, and the financial and tax advantages so great, why isn't everyone pouring money into the drug industry? Why aren't VC firms lining up to get in on this sweet deal? I mean, $43 million for a drug, you should be able to raise that pretty easily, even in this climate - and then you just stand back as the money gushes into the sky. Don't you?

Why are drug approval rates so flat (or worse?) Why all the layoffs? Why all the doom and gloom? We're apparently doing great, and we never even knew.

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February 28, 2011

Down In Phase III. Again.

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Posted by Derek

Past performance (Phase II results) are no guarantee of future success (Phase III). That warning has been proven over and over in this business, and an awful lot of time, effort, and money have gone down the waste chute in the process. To give you an idea, though, of how hard it is to break out of that cycle, consider Renovo.

As the InVivoBlog details, Renovo was founded to try out ideas to reduce scar tissue formation. And their whole strategy was to go into humans as quickly as possible, to firm up the clinical relevance of their candidate therapies. That's a bit easier to do with something like scarring, if you can find patients willing to have small cuts made in their skin. That's just how one of the Phase II trials was run for the company's Juvista (recombinant TGF beta 3) - two cuts, one treated with the drug and one without. And the results looked quite good.

But not in Phase III. Earlier this month, the company announced that Juvista has completely, utterly missed its endpoints in the larger trial, and no one seems to know why. According to the InVivoBlog, investors were reduced on the conference call to asking if somehow the data collection had been messed up - surely some of the placebo group and the treatment group had been, uh, switched somehow? But no.

It's worth remembering, though, that not all the Phase II data were so convincing. In retrospect, the earlier trials that looked bad were predictive, while the impressive numbers appear to have been artifacts. But how do you figure that out in advance? And how do you run only the trials that will be predictive, and how do you know to trust them? I'm tempted to ask Francis Collins to get on this for all of us, but that would be unfair. I think.

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February 23, 2011

Gonna Focus on Re-Engineering the Tools for the Process

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Posted by Derek

I have tried several times to get my hands around what NIH head Francis Collins is talking about here (note: open-access article), but I now admit defeat. Allow me to quote a bit, and we'll see if anyone else out there has more luck:

We have seen a deluge of new discoveries in the last few years on the molecular basis of disease. . .(But despite) increasing investments by the private sector, there has been a downturn in the number of approved new molecular entities over the last few years. Also, drug development research remains very expensive and the failure rate is extremely high.

Perhaps in part responding to these factors, and to the downturn in the economy, pharmaceutical companies have cut back their investments in research and development. We can't count on the biotech community to step in and fill that void either, because they are hurting from an absence of long-term venture capital support. So, we have this paradox: we have a great opportunity to develop truly new therapeutic approaches, but are undergoing a real constriction of the pipeline. One solution is to come up with a non-traditional way of fostering drug development — through increased NIH involvement.

Hmm. I may have missed the deluge that he's talking about, but we'll set that concern aside. What might this "non-traditional way" look like? Collins again:

I like to think of this in a broad sense of “what kind of paradigm can we initiate and expand between academic researchers and the private sector to move the therapeutic agenda forward?” . . .By having the NIH more engaged in the pipeline, we can also ask whether we can improve the success rates of drug development. . .We need to re-engineer the process, with a lot more focus on the front end.

Right! Another thick block of wobbling gelatin. Let's see, we're going to get the NIH engaged, and, um, give them the tools, and re-engineer things, and oh yeah, focus. Definitely going to focus. Any more details to add?

There are a lot of moving parts to this set of resources that ultimately need to be synthesized into a smooth process. One of my goals over the next year is to try to identify ways to put these together into a more seamless enterprise.

Good to hear. Please, those of you with access to (see above) Nature Reviews Drug Discovery, where this interview appeared, take a look and see if you can condense anything more out of it than I did. I mean, King Lear had a more concrete plan of action than this one: "I will do such things - what they are, yet I know not, but they shall be the terrors of the earth."

Update: an NRDD editor has let me know that the interview is open access. He also points out that the piece was done before the official announcement of the NCATS idea. My take is while that might account for a bit of the fuzziness, everything I've seen since then has been similarly soft-focus. . .

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February 14, 2011

New Cures! Faster! Faster!

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Posted by Derek

I wrote here the other day about the NIH's new translational medicine plans. The New York Times article that brought this to wide attention didn't go over well with director Francis Collins, who ended up trying to disabuse people of the idea that the NIH was going to set up its own drug company.

But there's been an overwhelming negative response from the academic research community, largely driven (it seems) by worries about funding. Given the state of the budget, flat funding would be seen as a victory by NIH, so this isn't the best environment to be talking about putting together a great new institute. The money for it will, after all, have to come out of someone else's pile. Collins spends most of that statement linked above denying this, but it's hard to see how there won't be problems.

I think, though, that there's an even more fundamental problem here. In the latest BioCentury, there's an interesting sidelight on all this:

In comments submitted to NIH, Joseph Zaia, associate director of the Center for Biomedical Mass Spectrometry at the Boston University School of Medicine, argued against setting timetables for research results. “I do not believe that running medical science on a short sighted business time schedule will produce more cures faster. It will, however, deplete NIH resources very rapidly and possibly tear down an infrastructure of knowledge that took decades to create.”

Zaia complained that the NCATS “process seems to be driven by the FasterCures movement sponsored by Michael Milken,” which he said has “been masterful in manipulating the political system for their purposes, and forcing NIH into this reorganization.”

FasterCures’ Margaret Anderson, executive director of the non-profit group that advocates for accelerating medical innovation, submitted a letter strongly endorsing NCATS, which she said “will provide a significant stimulus to moving ideas out of the lab and into the clinic.”

And that's the problem. Over the last few years, an idea has taken hold that there are all kinds of great ideas for all kinds of diseases that no one is doing anything with. Now, I'm not going to claim that everyone is trying every single thing that could possibly be tried, but I really don't see how there's this treasure chest of great discoveries that aren't being followed up on. Drug companies of all sizes are always watching for such opportunities - I've been a part of many such efforts to jump on these as they show up.

My guess is that many of these advocates have a different definition of what a "great discovery" is than I do. There are all kinds of things that come out in the literature, often with breathless press releases from the university PR office, that make it sound like the latest JBC paper has the cure for cancer in it. But the huge majority of these things don't pan out, generally because they're just part of a much, much larger (and more complicated) story. And that's why things tend to fail on the way to (and through) the clinic.

Am I exaggerating? Well, many advocates in this area have taken to using the phrase "valley of death" to describe the gap between basic research and success in the clinic. Here's Amy Rick of the Parkinson's Action Network:

Rick said patient groups are concerned that the valley of
death is growing, and they want government to help bridge it. The prospect that there are “good discoveries that are basically collecting dust” is “terrifying to patients,” she said.

“What we are finding from a patient perspective is that discoveries that are being made in very exciting basic research are not being acted upon,” Rick told BioCentury This Week. “They are not moving through the pipeline. So the patient community is pushing very hard — if private money isn’t filling that space, the government should be moving some of its funding into that space.”

I have a great deal of sympathy for the patient population - they're our customers in this business, after all, and any one of us could join their ranks at any time. (Drug company researchers come down with all the maladies that everyone else does). But the patient population is not the group of people discovering and developing drugs. What looks like agonizingly slow progress from outside is often just the best that can be done. It can be hard to imagine how crazy, complex, and frustrating medical research can be unless you've tried doing it. Nothing else quite compares.

I worry that some of these people have an unrealistic view of how things work (or should work). This all reminds me of Andrew Grove, ex-Intel, and his complaints that the drug research business wasn't moving as fast as the semiconductor industry. It sure isn't. That's because it's a lot harder.

The Biocentury article is right in line with my thinking here:

FASEB’s Talman argues that patient groups and the public are overly optimistic about the breakthroughs that could be made by shifting resources to translational science. He believes basic scientists are partly to blame because “there is too much of a tendency for basic or clinical scientists to sell our work.” In the process, he said, “we can come across as saying that the newest discovery can lead to a cure.”

Senior NIH officials have contributed to the belief that cures are around the corner by dangling the prospect of quick payoffs in front of congressional appropriators. For example, in 1999, Gerald Fischbach, then director of the National Institute of Neurological Diseases and Stroke, told a Senate committee that with sufficient funding it was reasonable to expect a cure for Parkinson’s disease within five years. The NINDS budget has increased from $902 million in FY99 to $1.6 billion in FY10, but PD hasn’t been cured.

Starting in 2004, National Cancer Institute Director Andrew von Eschenbach claimed in numerous public speeches that it would be possible to “end suffering and death from cancer by 2015,” a claim that current NCI Director Harold Varmus has repudiated.

When he led the human genome sequencing effort, NIH Director Collins himself made comments that the press, public and politicians interpreted as promising that it would directly and quickly lead to new medicines for common diseases.

“There is a real danger of over-promising,” Keith Yamamoto, executive vice dean of the University of California San Francisco School of Medicine, told BioCentury. “Scientists too often take an intellectual short cut. They think they will not be able to explain the nuances of why basic discovery takes so long, so they just say if you give me the money we are about to cure the disease.”

He added: “That’s thin ice — it is our responsibility to explain why things are as difficult as they are.”

It sure is. I know that patients and the general public get tired of hearing about how it's hard, how discoveries take time, all that sort of thing, while the diseases just keep marching on and on. But it's all true. I honestly don't think that most people realize, despite that huge amounts of knowledge we've managed to accumulate, just how little we know about what we're doing.

Comments (39) + TrackBacks (0) | Category: Academia (vs. Industry) | Cancer | Drug Development | The Central Nervous System

February 11, 2011

Drug Problems: A Diagnosis

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Posted by Derek

There's no shortage of "What's Wrong With the Drug Industry" article these days. I wanted to call attention to another one that's just appeared in JPET. I don't agree with all of it, but it does make some important points.

If I had to give a one-line summary of its thesis, it would be "Drug discovery forgot pharmacology and lost its way". The author, Michael Williams of Northwestern (and of 35 years at Merck, Novartis, Abbott, and Cephalon) is a pharmacologist himself, and feels that the genomics era (and indeed, the whole target-driven molecular biology era) has a lot to answer for. He also thinks that people have become seduced by technology:

Rather than creating synergies by using multiple complementary
technologies to find answers to discrete questions in a focused and coherent manner, technology-driven drug discovery has become a discipline that justifies its existence by searching for questions. An example of this is the proteomics approach to target validation, where the intrinsic complexity of the protein component of a cell or tissue necessitates a reductionistic approach where experimental samples must be separated into bins to facilitate analysis with timelines for data generation that can stretch into months or years.

To those with a technology bent, new iterations on a technology, regardless of its utility, inevitably become “must haves,” with acquisition and implementation becoming ends unto themselves. . .

One place I disagree with him is in his assertion that "Implicit in the HTS/combinatorial chemistry paradigm was/is that each target was equally facile as a starting point for a drug discovery project". That hasn't been my experience at all - there's always been a lot of arguing about which targets should be taken to screening and of what kind (how many GPCRs versus enzymes versus what-have you). Williams makes his point in the context of the genomics frenzy, when it was thought that all kinds of targets would be emerging. But at least where I worked, the hope was that genomics would provide a lot of good, tractable target that we hadn't known about, rather than just a long list of orphan receptors and whatzitases. (Mind you, that list is exactly what we ended u with).

Williams then discusses the problem of whether some targets are, in the end, truly intractable. The "just one more whack at it, and we'll get there" approach sometimes works, but it does try the patience:

Drugs active at opioid receptors remain the gold standard of analgesic care and include morphine, codeine, and oxycodone. With the discovery of the mu, delta, and kappa receptor subtypes in the 1970s, it was anticipated that development of selective agonists for these receptors would result in drugs that had a reduced liability for the respiratory depression, tolerance, constipation, and addiction associated with classical opioids. Some 40 years later, despite considerable efforts in medicinal chemistry and molecular biology to refine/define the structural characteristics of receptor-selective NCEs, the ”holy grail” of side effect-free opioids appears as elusive as ever, with a multitude of compounds showing compelling preclinical data but failing to demonstrate these properties in the clinic. . .

Another of his examples in this line are the muscarinic ligands, which I know from personal experience, as a search of my name through the literature and patent databases will show. And although GPCRs are among the most valuable target classes of all, we still have to face up to some disturbing facts about them:

Thus, for both of these G protein-coupled receptor families, a major question is whether their function is so critical, nuanced, and complex as to preclude advances based on the molecular approaches currently being used that may lack the necessary heuristic relationship to the complexity/redundancies of the systems present in a more physiological or disease-related milieu. Based on progress over the past 40 years, it may well be concluded that the opioid and muscarinic receptor families represent intractable targets in the search for improved small-molecule therapeutics. But maybe the next NCE….???

At the end of the article is a table of possible approaches to get out of the preclinical swamp. Interestingly, it's noted that it was "generated at the request of one of the reviewers", who probably asked what the author proposed to do about all this. I won't reproduce it all here, but it boils down to being more rigorous about data and statistics, using the hardest, most real-world models, and giving people the time to pursue these approaches even if they're going against the crowd while doing so. I don't see any his recommendations that I disagree with, but (and this isn't his fault), I don't see any of them that I haven't seen before, either. There needs no ghost, my lord, come from the grave, to tell us this.

Comments (23) + TrackBacks (0) | Category: Drug Development | Drug Industry History

February 7, 2011

Fragments Versus DOS: A Showdown

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Posted by Derek

Nature has side-by-side editorial pieces about fragment-based drug discovery versus diversity-oriented synthesis (DOS). I've written about both topics here before (DOS here and here, fragments here and here), and it should be fairly clear that I favor the former. But both ideas deserve a hearing.

Background, for those who aren't having to think about this stuff: the fragment-based approach is to screen a reasonable set (hundreds to low thousands) of small (MW 150 to 300) molecules. You won't find any nanomolar hits that way, but you will find things that (for that molecular weight) are binding extremely efficiently. If you can get a structure (X-ray, most of the time), you can then use that piece as a starting point and build out, trying to keep the binding efficiency high as you go. Diversity-oriented synthesis, on the other hand, tries to make larger molecules that are in structural spaces not found in nature (or in other screening collections, either). It's a deliberate attempt to make wild-blue-yonder compounds in untried areas, and is often used to screen against similarly untried targets that haven't shown much in conventional screening.

The two articles make their cases, but spend some time talking past each other. Abbott's Phil Hajduk takes the following shots at DOS: that it's tended to produce compounds whose molecular weights are too high (and whose other properties are also undesirable), and that it needs (in order to cover any meaningful amount of chemical space at those molecular weights) to produce millions of compounds, all of which must then be screened. Meanwhile, Warren Galloway and David Spring of Cambridge make the following charges about fragment work: that it only works when you have a specific molecular target in mind (and that only then when you have high-quality structural information), that it tends to perform poorly against the less tractable targets (such as protein-protein interactions), and that fragments (and the molecules derived from them) tend not to be three-dimensional enough.

Here's my take: I like phenotypic screening, where you run compound collections across cells/tissues/small animal models and see what works. And fragment are indeed next to useless for that purpose. But I agree with Hajduk that most of the DOS compound libraries I've seen are far too large and ugly to furnish anything more than a new probe compound from such screens. There are many academic labs for whom that's a perfectly good end point, and they publish a paper saying, in short, We Found the First Compound That Makes X Cells Do Y. Which is interesting, and can even be important, but there's often no path whatsoever from that compound to an actual drug. I'd prefer that DOS collections not get quite so carried away, and explore new structural motifs more in the range of druglike space. But that's not easy - new structures are a lot easier to come by if you're willing to make compounds with molecular weights of 500 to 1000, since (a) not so many people have made such beasts before, and (b) there are a lot more possible structures up there.

Now, if I have a defined target, and can get structures, I'd much prefer to do things the fragment way. But this is where the two editorial talk past each other - they both beat the drum for what they do well, but they do different things well. It's the parts where they overlap that I find most interesting. One of those is, as just mentioned, the problem that DOS compounds tend to be too large and undevelopable (with one solution being to go back and make them more tractable to start with). The other overlap is whether fragment collections can hit well against tough targets like protein-protein interactions. I don't know the answer to that one myself - I'd be glad to hear of examples both pro and con.

So we'll call this a struggle still in progress. With any luck, both techniques will keep each other's partisans on their toes and force them to keep improving.

Comments (33) + TrackBacks (0) | Category: Drug Assays | Drug Development

February 1, 2011

The NIH's New Drug Discovery Center: Heading Into the Swamp?

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Posted by Derek

I've been meaning to comment on the NIH's new venture into drug discovery, the National Center for Advancing Translational Sciences. Curious Wavefunction already has some thoughts here, and I share his concerns. We're both worried about the gene-o-centric views of Francis Collins, for example:

Creating the center is a signature effort of Dr. Collins, who once directed the agency’s Human Genome Project. Dr. Collins has been predicting for years that gene sequencing will lead to a vast array of new treatments, but years of effort and tens of billions of dollars in financing by drug makers in gene-related research has largely been a bust.

As a result, industry has become far less willing to follow the latest genetic advances with expensive clinical trials. Rather than wait longer, Dr. Collins has decided that the government can start the work itself.

“I am a little frustrated to see how many of the discoveries that do look as though they have therapeutic implications are waiting for the pharmaceutical industry to follow through with them,” he said.

Odd how the loss of tens of billions of dollars - and vast heaps of opportunity cost along the way - will make people reluctant to keep going. And where does this new center want to focus in particular? The black box that is the central nervous system:

Both the need for and the risks of this strategy are clear in mental health. There have been only two major drug discoveries in the field in the past century; lithium for the treatment of bipolar disorder in 1949 and Thorazine for the treatment of psychosis in 1950.

Both discoveries were utter strokes of luck, and almost every major psychiatric drug introduced since has resulted from small changes to Thorazine. Scientists still do not know why any of these drugs actually work, and hundreds of genes have been shown to play roles in mental illness — far too many for focused efforts. So many drug makers have dropped out of the field.

So if there are far too many genes for focused efforts (a sentiment with which I agree), what, exactly, is this new work going to focus on? Wavefunction, for his part, suggests not spending so much time on the genetic side of things and working, for example, on one specific problem, such as Why Does Lithium Work for Depression? Figuring that out in detail would have to tell us a lot about the brain along the way, and boy, is there a lot to learn.

Meanwhile, Pharmalot links to a statement from the industry trade group (PhRMA) which is remarkably vapid. It boils down to "research heap good", while beating the drum a bit for the industry's own efforts. And as an industrial researcher myself, it would be easy for me to continue heaping scorn on the whole NIH-does-drug-discovery idea.

But I actually wish them well. There really are a tremendous number of important things that we don't know about this business, and the more people working on them, the better. You'd think. What worries me, though, is that I can't help but believe that a good amount of the work that's going to be done at this new center will be misapplied. I'm really not so sure that the gene-to-disease-target paradigm just needs more time and money thrown at it, for example. And although there will be some ex-industry people around, the details of drug discovery are still likely to come as a shock to the more academically oriented people.

Put simply, the sorts of discoveries and project that make stellar academic careers, that get into Science and Nature and all the rest of them, are still nowhere near what you need to make an actual drug. It's an odd combination of inventiveness and sheer grunt work, and not everyone's ready for it. One likely result is that some people will just avoid the stuff as much as possible and spend their time and money doing something else that pleases them more.

What do I think that they should be doing, then? One possibility is the Pick One Big Problem option that Wavefunction suggests. What I'd recommend would also go against the genetic tracery stuff: I'd put money into developing new phenotypic assays in cells, tissues, and whole animals. Instead of chasing into finer and finer biochemical details in search of individual targets, I'd try to make the most realistic testbeds of disease states possible, and let the screening rip on that. Targets can be chased down once something works.

But it doesn't sound like that's what's going to happen. So, reluctantly, I'll make a prediction: if years of effort and billions of dollars thrown after genetic target-based drug discovery hasn't worked out, when done by people strongly motivated to make money off their work, then an NIH center focused on the same stuff will, in all likelihood, add very little more. It's not like they won't stay busy. That sort of work can soak up all the time and money that you can throw at it. And it will.

Comments (35) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development | Drug Industry History

January 31, 2011

What's the Most Worthwhile New Drug Since 1990?

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Posted by Derek

A query from a reader prompts me to ask this question, in preparation for a rather long post in the new future. What do you think is the most worthwhile new pharmaceutical brought to market since 1990? That's an arbitrary cutoff, but twenty years is a reasonable sample size. And I'll let everyone define "worthwhile" as they see fit - improvement over existing drugs, opening new therapeutic areas, cost-effectiveness, what have you. Just be sure to make your case, briefly, when you nominate a candidate. Let's see, first off, if it's a topic that can be agreed on at all.

Comments (61) + TrackBacks (0) | Category: Drug Development | Drug Industry History

January 21, 2011

Oh, And While You're At It. . .

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Posted by Derek

Well, this is a question that (I must admit) had not crossed my mind. Courtesy of Slate, though, we can now ask how we can make pharmaceuticals more environmentally friendly. No, not the manufacturing processes: this article's worried about the drugs that are excreted into the water supply.

It's worth keeping an eye on this issue, but I haven't been able, so far, to get very worked up about it. It's true that there have been many studies that show detectable amounts of prescription drugs in the waste water stream. The possible environmental effects mentioned in the article, though, are seen at much higher concentrations. I think that much of the attention given to this issue comes from the power of modern analytical techniques -if you look for things at parts-per-billion level (or below), you'll find them. Of course, you'll also find a huge number of naturally occurring substances that are also physiologically active: can the synthetic estrogen ligands out there really compete against the huge number of phytoestrogens? I have to wonder. To me, the sanest paragraph of the article is this one:

Developing "benign-by-design" drugs poses a series of vexing challenges. In general, the qualities that make drugs effective and stable—bioactivity and resistance to degradation—are the same ones that cause them to persist disturbingly after they've done their job. And presumably even hard-core eco-martyrs (the ones who keep the thermostat at 60 all winter and renounce air travel) would hesitate to sacrifice medical efficacy for the sake of aquatic wildlife. What's more, the molecular structures of pharmaceuticals are, in the words of Carnegie Mellon chemist Terry Collins, "exquisitely specific." Typically, you can't just tack on a feature like greenness to a drug without affecting its entire design, including important medical properties.

And even that one has its problems. That "persist disturbingly" phrase makes it sound like pharmaceuticals are like little polyethylene bags fluttering around the landscape and never wearing down. But it's worth remembering that most drugs taken by humans are metabolized on their way out of the body, and most of these metabolites don't maintain the activity of the parent compound. Other organisms have similar metabolic powers - as living creatures, we've evolved a pretty robust ability to deal with constant low levels of unknown chemicals. (Here's a good chance to point out this article by Bruce Ames and Lois Swirsky Gold on that topic as it relates to cancer; many of the same points apply here).

No one can guarantee, though, that pharmaceutical residue will always be benign. As I say, it's worth keeping an eye on the possibility. But it will indeed be hard to do something about it, for just the reasons quoted above. As it is, getting a drug molecule that hits its target, does something useful when that happens, doesn't hit a lot of other things, works in enough patients to be marketable, has blood levels sufficient for a convenient dose, doesn't cause toxic effects on the side, and can be manufactured reproducibly in bulk and formulated into a stable pill. . .well, that's enough of a challenge right there. We don't actually seem to be able to do that well enough as it stands. Making the molecules completely eco-friendly at the same time. . .

Comments (47) + TrackBacks (0) | Category: Drug Development | Toxicology

January 20, 2011

Merck's Vorapaxar: Bleeding, Indeed

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Posted by Derek

So, as had been suspected, the reason that Merck's thrombin antagonist vorapaxar ran into clinical trouble was excessive bleeding. This is always the first thing to suspect when an anticoagulant has difficulty in human trials.

It's really a delicate balance, the human clotting cascade, and it's all too easy to end up on the wrong side of it. When you think about it, the whole pathway has to be under very tight regulation - I mean, here's the fluid that transports oxygen and nutrients and removes waste. Absolutely crucial to the life of every cell in the body. And here's an option to have that fluid thicken up and turn to jelly, very quickly, and once it happens it can't be reversed. No, you're going to want a lot of safeguards around that switch. But if you lean over too far the other way, well. . .there's a lot of vascular plumbing in the body, and it gets a lot of stress. Leaks and rips are inevitable. You have to have a method for patching holes, and it has to be ready to go everywhere, at all times. Dial it down just a bit too much, and hemorrhages are inevitable. Thus all the different clotting mechanism steps, and the different drugs targeting them.

As Matthew Herper explains at that link above, the prospect for this drug are completely dependent on which side of the line it ends up on. In this patient population, it's already stepped over - another result like this one, and vorapaxar could be completely sunk.

Comments (8) + TrackBacks (0) | Category: Cardiovascular Disease | Clinical Trials | Drug Development

January 13, 2011

Merck's Thrombin Antagonist In Trouble

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Posted by Derek

Very bad news today for Merck (and the Schering-Plough people therein). Their thrombin receptor antagonist vorapaxar (formerly SCH 530348) has run into trouble.

A review board monitoring the compound's clinical trials has suddenly halted two of them. All we know at the moment is that the drug is "not appropriate for stroke patients", and it's also being pulled from a study in people who have had mild heart attacks. The best guess, as with any drug in the clotting field, is that it may be causing bleeding instead, but we'll have to see. Problem is, those are two of the more important patient populations that a company would be targeting, and if there's trouble in those groups, then it could be waiting to show up in others as well.

Vorapaxar has an unusual history at Schering-Plough (I wrote about it here, with some personal experiences from my own time at the company thrown in). I'm very sorry to see this news - sorry for the patients involved (and those who won't be helped later on), for the researchers involved (several of whom I've worked with in the past), and for Merck's investors, who are taking about a 6% trim today on the NYSE.

This compound wasn't the whole reason for Merck to buy Schering-Plough, but it wasn't a small part of the deal, either. That other stuff had better work out. . .

Comments (12) + TrackBacks (0) | Category: Business and Markets | Cardiovascular Disease | Clinical Trials | Drug Development

January 12, 2011

Gassing Your Crystals

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Posted by Derek

Now, this is a pretty neat trick. One of the things that drug development people have to worry about a lot is the crystal forms of the new compound. You might imagine (if you haven't had to do this stuff) that if a compound is crystalline, then that's that - you've got the solid form now, and full speed ahead.

But many substances can crystallize in all sorts of forms - here's one with at least seven different solved crystal structures (and it has more that haven't yielded an X-ray structure yet). By the time you bring in solvates, where the molecule crystallizes along with the solvent it was last in, or with water dragged in from the air, or what have you, you can go well up into the double digits, and we haven't even begun talking about salt forms yet. Each one of those starts the whole counter running all over again. These polymorphs have different melting points, different rates of dissolution, and different behavior when they hit the stomach, and these are all things that you have to worry about.

There have been several real holdups in the drug industry, where a compound that had been developed as one form suddenly decided that it would rather be another one when the chemistry was scaled up. That blows out all the blood levels and dosing protocols that were worked out before. Sometimes the new form can be used, once all the data are re-acquired, but sometimes it turns out to be unusably worse than the old form. The challenge then is: how do you get it to be one rather than the other? And how can you be sure that it'll happen every time?

So we're always interested in ways to make molecules take on different crystal forms, and in ways to make them switch from one to another. That's where this latest paper comes in. They've found that you can expose solvated crystals to pressurized carbon dioxide gas and alter the crystalline forms. The gas molecules work their way into the crystal lattice, displace the solvate molecules, and then when the pressure is taken off, they work their way back out again (or can be persuaded to with a little heat). It's an ingenious idea, and you can bet that development scientists all over the industry have saved copies of this paper already. We need all the help we can get!

Comments (16) + TrackBacks (0) | Category: Drug Development

January 5, 2011

How to Fund a Nonprofit Drug Company - And Others?

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Posted by Derek

Here's a business idea for a nonprofit drug company, sent along by reader and entrepreneur Matt Grosso. I don't necessarily think that it would work (see below), but it's worth talking about, since some of its features are worthwhile. Others, though, illustrate what may be some common misperceptions of how drug development works. Here's the key feature:

The idea here is to create a non-profit which would accept contributions for testing and bringing to market specific drugs. . .Members would vote with their contribution dollars for specific drugs. Paid staff would curate a wiki that supported periodic comparisons between various candidates approaching readiness for a specific market, which would ensure that that member votes had the benefit of the best available information and expert opinion.

This could create an alternate route for drug startups focused on particular compounds to get their product to market.

I think that the ability to specifically take in contributions is a good one - people and organizations are more likely to fund defined aims that they agree with. One big problem, though, is that there's a limit to which we can define such things in this business. And that might make the whole idea break down.

To be honest, if a nonprofit really took in contributions for the development of specific drugs, they'd run a great risk of disappointing and enraging their donation base. That's because the honking huge majority of specific drugs in development never make it. The success rates in the clinic are pretty well known: roughly 90% of everything that goes into clinical trials never makes it to market. That's a hard sell for contributors! And if you moved the point at which you asked for donations back into the preclinical stage, the situation would get much, much worse. At the "Hey, we just thought of a neat new target" step, you'd be offering your contributors worse odds and payoffs than they could get in the state lottery.

For new compounds and new modes of action, the risks decrease in roughly the following order. At the same time, the time it takes to get an answer increases in the roughly the same way:

1. Specific single compound with a defined mechanism. Hold your breath, and good luck!
2. Defined chemical class of compounds targeting the same mechanism. Now you've got some fallback, although it might not be enough to help in case of trouble.
3. Specific mechanism, with several chemical series. This gives you several shots, although if your mechanism of action is off, all will still be in vain.
4. Phenotypic readout with a range of compounds (that is, they seem to do the right thing, but you're not sure how). Risk varies according to how realistic your assays are, and how many different compounds you've picked up.
5. Targeting a broad class of related mechanisms - for example, "reduce LDL", "disrupt bacterial membranes", "interrupt inflammatory cascade". Note that we're now getting farther and farther away from individual compounds.
6. Targeting one specific therapeutic area: antivirals, Alzheimer's, osteoporosis, etc.
7. Trying to balance things out with several therapeutic areas, with projects in each one at varying levels of risk.

Note that we've also illustrated the progression from "wing and a prayer startup" to "fully integrated drug company". That follows exactly from the levels of risk involved, which correlates with the amount of money on the table as well, in exactly the way the ranking of poker hands correlates with how likely they are to occur. Note also that even in that final stage, we apparently still have not mitigated the risks enough, given our cost structure. (Look at the state of the industry).

To get back to the nonprofit idea, another thing that might work out less well in practice than it does in principle might be that wiki for the potential investors/donors. This is what companies try to do internally: comparing their programs by the same criteria, head to head, then determining how to resource them. 'Taint easy. I don't know of any organization that truly thinks that they do as well at this as they should. Even a bunch of perfectly clear-headed and honest assessments (which, by the way, cannot be universally assumed) are still complicated by unquantifiable risks. I think that people might be alarmed by the number of times you just have to push things ahead to see what's going to happen.

Even after all these qualifications, though, I think that there's merit in the idea of breaking out individual drug development programs. I've long kicked around the idea of whether a company could fund programs by essentially selling shares in its various clinical candidates, with a cut of the profits coming if things work out. It would be an accounting mess, and everyone would have to keep those failure rates in mind, but there are still people who'd be willing to take a crack at it, for a given level of possible return. Those donors/investors might even be less put out than the charitable/nonprofit ones - everyone's had investments go bad, but no one wants to feel like their charitable donation was wasted. Thoughts?

Comments (20) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

November 30, 2010

More Advice From Andrew Witty

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Posted by Derek

Andrew Witty of GSK has a one-page essay in The Economist on the problems of the drug industry. None of the background he gives will be news to anyone who reads this site, as you'd imagine - lower rates of success in discovery, higher costs, patent expirations, etc.

Here's his take on research and development:

. . .it is clear that the size of the industry will continue to contract in the drive for efficiency. For some players, more mergers and acquisitions are likely, but others will plan to shrink, and all parts of the value chain from R&D through to production and sales and marketing will be affected. . .

. . .In the past the problem of R&D in big pharmaceutical companies has been “fixed” by spending more and by using scale to “industrialise” the research process. These are no longer solutions: shareholders are not prepared to see more money invested in R&D without tangible success. If anything, based on a rational allocation of capital, R&D should now be consuming less resource.

Yikes. I'm not sure where that last sentence comes from, to be honest with you. Does Witty think that we now know so much about what we're doing that it shouldn't cost so much for us to do it? Or that it shouldn't cost so much to comply with the regulatory authorities, for some reason? I'm a bit baffled, and if someone can explain that "rational allocation" that he speaks of, I'd be grateful.

And I'd like to say that the rest of the piece advances some useful ideas, but I can't do that with a straight face. (To be fair, if Andrew Witty has some great ideas for making GSK more productive, he's most certainly not going to lay them out for everyone in The Economist). So it's all innovative business models, dynamic partnerships, recapturing creative talent in the drug labs, and so on. That last line will no doubt inspire a lot of bitter comment, considering what things have been like at GSK in the last few years.

His main pitch seems to be that drug companies need a "fair reward for innovation", and that's one of those things that's hard to disagree with on the surface. But unpacking it, that's the tough part, because everyone involved will start disagreeing on what's innovative, what might constitute a reward, and (especially) what's fair. Witty has been giving speeches on this for a while now, and I'd say that this latest article is just the condensed version.

Comments (55) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

November 23, 2010

Of Deck Chairs, Six Sigma, And What Really Ails Us

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Posted by Derek

We talked a little while back here about "Lean Six Sigma" as applied to drug discovery organizations, and I notice that the AstraZeneca team is back with another paper on the subject. This one, also from Drug Discovery Today, at least doesn't have eleventeen co-authors. It also addresses the possibility that not everyone in the research labs might welcome the prospect of a business-theory-led revolution in the way that they work, and discusses potential pitfalls.

But I'm not going to discuss them here, at least not today. Because this reminds me of the post last week about the Novartis "Lab of the Future" project, and of plenty of other initiatives, proposals, alliances, projects, and ideas that are floating around this industry. Here's what they have in common: they're all distractions.

Look, no one can deny that this industry has some real problems. We're still making money, to be sure, but the future of our business model is very much in doubt. And those doubts come from both ends of the business - we're not sure that we're going to be able to get the prices that we've been counting on once we have something to sell, and we're not sure that we're going to have enough things to sell in the first place. (There, that summarized about two hundred op-ed pieces, some of them mine, in one sentence. Good thing that I'm not paid by the word for this blog.) These problems are quite real - we're not hallucinating here - and we're going to have to deal with them one way or another. Or they're going to deal with us, but good.

I just don't think that tweaking the way that we do things will be enough. We're not going to do it by laying out the labs differently, or putting different slogans up on the walls, or trying schemes that promise to make the chemists 7.03% more productive or reduce downtime in the screening group by 0.65 assays/month. This is usually where people trot out that line about rearranging deck chairs on the Titanic, but the difference is, we don't have to sink. The longer things go on, though, the more I worry that incremental improvements aren't going to bail us out.

This is a bit of a reversal for me. I've said for several years that the low success rates in the industry mean that we don't necessarily have to make some huge advance. After all, if we made it up to just 80% failure in the clinic, that would double the number of drugs reaching the market. That's still true - but the problem is, I don't see any signs of that happening. If success rates are improving anywhere, up and down the whole process from target selection to Phase III, it's sure not obvious from the data we have.

What worries me is that the time spent on less disruptive (but more bearable) solutions may be taking away from the time that needs to be spent on the bigger changes. I mean, honestly, raise your hands: who out there thinks that "Lean Six Sigma" is the answer to the drug industry's woes? Right. Not even all the consultants selling this stuff could get that one out with a straight face. "But it'll help!" comes the cry, "and it's better than doing nothing!". Well, in the short term, that may be true, although I'm not sure if there is a "short term" with some of these things. If it gives managers and investors the illusion that things are really being fixed, though, and if it takes mental and physical resources away from fixing them, then it's actually harmful.

What would it take to really fix things? Everyone knows - really, everyone does. Some combination of progress on the following questions would do just fine:

1. A clear-eyed look at target-based drug design, by which I mean, whether we should be doing it at all. More and more, I worry that it's been a terrible detour for the whole project of pharmaceutical research. There have been successes, of course, but man, look at the failures. And the number of tractable targets (never high) is lower than ever, as far as I can tell. If we're going to do it, though, we need. . .

2. The ability to work on harder target classes. The good ol' GPCRs and the easy-to-inhibit enzyme classes are still out there, and still have life in them, but the good ideas are getting thinner. But there are plenty of tougher mechanisms (chief among them protein-protein interactions) that have a lot of ideas running around looking for believable chemical matter. Making some across-the-board progress in those areas would be a huge help, but it would avail us not without. . .

3. Better selection of targets. Too many compounds fail in the clinic because of efficacy, which means that we didn't know enough about the biology going in. Most of our models of disease have severe limitations, and in many cases, we don't even know what some of those limitations are until we step into them. Maybe we can't know enough in many cases, so we need. . .

4. More meaningful clinical trials. And by that I mean, "for a given cost", because these multi-thousand-people multi-year things, which you need for areas like cardiovascular, Alzheimer's, osteoporosis, and so on, are killing us. We've got a terrible combination of huge potential markets in areas where we hardly know what we're doing. And that leads to gigantic, expensive failures. Could they somehow be less expensive? One way would be. . .

5. A better - and that means earlier - handle on human tox. I don't know how to do this one, either, but there are billions of dollars waiting for you if you can. Efficacy is the big killer in the late clinic these days, but that and toxicity put together account for a solid majority of the failures all the way through. (The rest are things like "Oops, maybe we should sell this program off" kinds of decisions).

There are plenty of others, but I think that improvements in those would fix things up just fine. Don't you? And maybe I'm just slow-witted, but I can't see how changing the way the desks face, or swapping out all the business cards for new titles, or realigning the therapeutic area teams - again - are going to accomplish any of it. At best, these things will make the current process run a bit better, which might buy us some more time before we have to confront the big stuff anyway. At worst, they'll accomplish nothing at all, but just give the illusion that something's being done.

To be fair, there are some initiatives around the industry that address these (and the other) huge problems. As I said, it's not like no one knows what they are. And to be fair, these really are difficult things to fix. Saying that you want to get a better early read on human tox in the clinic, the way I just did so blithely, is easy - actually doing something about it, or even finding a good place to start doing something about it, is brutally hard. But it's not going to be as brutal as what's been happening to us the last few years, or what's we're headed for if we don't get cracking.

Comments (53) + TrackBacks (0) | Category: Business and Markets | Clinical Trials | Drug Development | Drug Industry History

November 11, 2010

And One Was Just Right?

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Posted by Derek

I've been reading an interesting new paper from Stuart Schreiber's research group(s) in PNAS. But I'm not sure if the authors and I would agree on the reasons that it's interesting.

This is another in the series that Schreiber has been writing on high-throughput screening and diversity-oriented synthesis (DOS). As mentioned here before, I have trouble getting my head around the whole DOS concept, so perhaps that's the root of my problems with this latest paper. In many ways, it's a companion to one that was published earlier this year in JACS. In that paper, he made the case that natural products aren't quite the right fit for drug screening, which fit with an earlier paper that made a similar claim for small-molecule collections. Natural products, the JACS paper said, were too optimized by evolution to hit targets that we don't want, while small molecules are too simple to hit a lot of the targets that we do. Now comes the latest pitch.

In this PNAS paper, Schreiber's crew takes three compound collections: 6,152 small commercial molecules, 2,477 natural products, and 6,623 from academic synthetic chemistry (with a preponderance of DOS compounds), for a total of 15, 252. They run all of these past a set of 100 proteins using their small-molecule microarray screening method, and look for trends in coverage and specificity. What they found, after getting rid of various artifacts, was that about 3400 compounds hit at least one protein (and if you're screening 100 proteins, that's a perfectly reasonable result). But, naturally, these hits weren't distributed evenly among the three compound collections. 26% of the academic compounds were hits, and 23% of the commercial set, but only 13% of the natural products.

Looking at specificity, it appears that the commercial compounds were more likely, when they hit, to hit six or more different proteins in the set, and the natural products the least. Looking at it in terms of compounds that hit only one or two targets gave a similar distribution - in each case, the DOS compounds were intermediate, and that turns out to be a theme of the whole paper. They analyzed the three compound collections for structural features, specifically their stereochemical complexity (chiral carbons as a per cent of all carbons) and shape complexity (sp3 carbons as a percent of the whole). And that showed that the commercial set was biased towards the flat, achiral side of things, while the natural products were the other way around, tilted toward the complex, multiple-chiral-center end. The DOS-centric screening set was right in the middle.

The take-home, then, is similar to the other papers mentioned above: small molecule collections are inadequate, natural product collections are inadequate: therefore, you need diversity-oriented synthesis compounds, which are just right. I'll let Schreiber sum up his own case:

. . .Both protein-binding frequencies and selectivities are increased among compounds having: (i) increased content of sp3-hybridized atoms relative to commercial compounds, and (ii) intermediate frequency of stereogenic elements relative to commercial (low frequency) and natural (high frequency) compounds. Encouragingly, these favorable structural features are increasingly accessible using modern advances in the methods of organic synthesis and commonly targeted by academic organic chemists as judged by the compounds used in this study that were contributed by members of this community. On the other hand, these features are notably deficient in members of compound collections currently widely used in probe- and drug-discovery efforts.

But something struck me while reading all this. The two metrics used to characterize these compound collections are fine, but they're also two that would be expected to distinguish them thoroughly - after all, natural products do indeed have a lot of chiral carbons, and run-of-the-mill commercial screening sets do indeed have a lot of aryl rings in them. There were several other properties that weren't mentioned at all, so I downloaded the compound set from the paper's supporting information and ran it through some in-house software that we use to break down such things.

I can't imagine, for example, evaluating a compound collection without taking a look at the molecular weights. Here's that graph - the X axis is the compound number, Y-axis is weight in Daltons:
PNAS%20AMW%20vs%20compound%20ID%2Cjpg.jpg
The three different collections show up very well this way, too. The commercial compounds (almost every one under 500 MW) are on the left. Then you have that break of natural products in the middle, with some real whoppers. And after that, you have the various DOS libraries, which were apparently entered in batches, which makes things convenient.

Notice, for example that block of them standing up around 15,000 - that turns out to be the compounds from this 2004 Schreiber paper, which are a bunch of gigantic spirooxindole derivatives. In this paper, they found that this particular set was an outlier in the academic collection, with a lot more binding promiscuity than the rest of the set (and they went so far as to analyze the set with and without it included). The earlier paper, though, makes the case for these compounds as new probes of cellular pathways, but if they hit across so many proteins at the same time, you have to wonder how such assays can be interpreted. The experiments behind these two papers seem to have been run in the wrong order.

Note, also, that the commercial set includes a lot of small compounds, even many below 250 MW. This is down in the fragment screening range, for sure, and the whole point of looking at compounds of that molecular weight is that you'll always find something that binds to some degree. Downgrading the commercial set for promiscuous binding when you set the cutoffs that low isn't a fair complaint, especially when you consider that the DOS compounds have a much lower proportion of compounds in that range. Run a commercial/natural product/DOS comparison controlled for molecular weight, and we can talk.

I also can't imagine looking over a collection and not checking logP, but that's not in the paper, either. But here you are:
PNAS%20cLogP%20vs%20compound%20ID%2Cjpg.jpg
In this case, the natural products (around compound ID 7500) are much less obvious, but you can certainly see the different chemical classes standing out in the DOS set. Note, though, that those compounds explore high-logP regions that the other sets don't really touch.

How about polar surface area? Now the natural products really show their true character - looking over the structures, that's because there are an awful lot of polysaccharide-containing things in there, which will run your PSA up faster than anything:
PNAS%20PSA%20vs%20compound%20ID.jpg
And again, you can see the different libraries in the DOS set very clearly.

So there are a lot of other ways to distinguish these compounds, ways that (to be frank) are probably much more relevant to their biological activity. Just the molecular-weight one is a deal-breaker for me, I'm afraid. And that's before I start looking at the structures in the three collections at all. Now, that's another story.

I have to say, from my own biased viewpoint, I wouldn't pay money for any of the three collections. The natural product one, as mentioned, goes too high in molecular weight and is too polar for my tastes. I'd consider it for antibiotic drug discovery, but with gritted teeth. The commercial set can't make up its mind if it's a fragment collection or not. There are a bunch of compounds that are too small even for my tastes in fragments - 4-methylpyridine, for example. And there are a lot of ugly functional groups: imines of beta-napthylamine, which should not even get near the front door (unstable fluorescent compounds that break down to a known carcinogen? Return to sender). There are hydroxylamines, peroxides, thioureas, all kinds of things that I would just rather not spend my time on.

And what of the DOS collection? Well, to be fair, not all of it is DOS - there are a few compounds in there that I can't figure out, like isoquinoline, which you can buy from the catalog. But the great majority are indeed diversity-oriented, and (to my mind), diversity-oriented to a fault. The spirooxindole library is probably the worst - you should see the number of aryl rings decorating some of those things; it's like a fever dream - but they're not the only offenders in the "Let's just hang as many big things as we can off this sucker" category. Now, there are some interesting and reasonable DOS compounds in there, too, but there are also more endoperoxides and such. (And yes, I know that there are drug structures with endoperoxides in them, but damned few of them, and art is long while life is short). So no, I wouldn't have bought this set for screening, either; I'd have cherry-picked about 15 or 20% of it.

Summary of this long-winded post? I hate to say it, but I think this paper has its thumb on the scale. I'm just around the corner from the Broad Institute, though, so maybe a rock will come through my window this afternoon. . .

Comments (36) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development | Natural Products

November 9, 2010

Where Drugs Come From: By Country

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Posted by Derek

The same paper I was summarizing the other day has some interesting data on the 1998-2007 drug approvals, broken down by country and region of origin. The first thing to note is that the distribution by country tracks, quite closely, the corresponding share of the worldwide drug market. The US discovered nearly half the drugs approved during that period, and accounts for roughly that amount of the market, for example. But there are two big exceptions: the UK and Switzerland, which both outperform for their size.

In case you're wondering, the league tables look like this: the US leads in the discovery of approved drugs, by a wide margin (118 out of the 252 drugs). Then Japan, the UK and Germany are about equal, in the low 20s each. Switzerland is in next at 13, France at 12, and then the rest of Europe put together adds up to 29. Canada and Australia put together add up to nearly 7, and the entire rest of the world (including China and India) is about 6.5, with most of that being Israel.

But while the US may be producing the number of drugs you'd expect, a closer look shows that it's still a real outlier in several respects. The biggest one, to my mind, comes when you use that criterion for innovative structures or mechanisms versus extensions of what's already been worked on, as mentioned in the last post. Looking at it that way, almost all the major drug-discovering countries in the world were tilted towards less innovative medicines. The only exceptions are Switzerland, Canada and Australia, and (very much so) the US. The UK comes close, running nearly 50/50. Germany and Japan, though, especially stand out as the kings of follow-ons and me-toos, and the combined rest-of-Europe category is nearly as unbalanced.

What about that unmet-medical-need categorization? Looking at which drugs were submitted here in the US for priority review by the FDA (the proxy used across this whole analysis), again, the US-based drugs are outliers, with more priority reviews than not. Only in the smaller contributions from Australia and Canada do you see that, although Switzerland is nearly even. But in both these breakdowns (structure/mechanism and medical need) it's the biotech companies that appear to have taken the lead.

And here's the last outlier that appears to tie all these together: in almost every country that discovered new drugs during that ten-year period, the great majority came from pharma companies. The only exception is the US: 60% of our drugs have the fingerprints of biotech companies on them, either alone or from university-derived drug candidates. In very few other countries do biotech-derived drugs make much of a showing at all.

These trends show up in sales as well. Only in the US, UK, Switzerland, and Australia did the per-year-sales of novel therapies exceed the sales of the follow-ons. Germany and Japan tend to discover drugs with higher sales than average, but (as mentioned above) these are almost entirely followers of some sort.

Taken together, it appears that the US biotech industry has been the main driver of innovative drugs over the past ten years. I don't want to belittle the follow-on compounds, because they are useful. (As pointed out here before, it's hard for one of those compounds to be successful unless it really represents some sort of improvement over what's already available). At the same time, though, we can't run the whole industry by making better and better versions of what we already know.

And the contributions of universities - especially those in the US - has been strong, too. While university-derived drugs are a minority, they tend to be more innovative, probably because of their origins in basic research. There's no academic magic involved: very few, if any, universities try deliberately to run a profitable drug-discovery business - and if any start to, I confidently predict that we'll see more follow-on drugs from them as well.

Discussing the reasons for all this is another post in itself. But whatever you might think about the idea of American exceptionalism, it's alive in drug discovery.

Comments (33) + TrackBacks (0) | Category: Academia (vs. Industry) | Business and Markets | Drug Development | Drug Industry History | Who Discovers and Why

November 4, 2010

Where Drugs Come From: The Numbers

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Posted by Derek

We can now answer the question: "Where do new drugs come from?". Well, we can answer it for the period from 1998 on, at any rate. A new paper in Nature Reviews Drug Discovery takes on all 252 drugs approved by the FDA from then through 2007, and traces each of them back to their origins. What's more, each drug is evaluated by how much unmet medical need it was addressed to and how scientifically innovative it was. Clearly, there's going to be room for some argument in any study of this sort, but I'm very glad to have it, nonetheless. Credit where credit's due: who's been discovering the most drugs, and who's been discovering the best ones?

First, the raw numbers. In the 1997-2005 period, the 252 drugs break down as follows. Note that some drugs have been split up, with partial credit being assigned to more than one category. Overall, we have:

58% from pharmaceutical companies.
18% from biotech companies..
16% from universities, transferred to biotech.
8% from universities, transferred to pharma.

That sounds about right to me. And finally, I have some hard numbers to point to when I next run into someone who tries to tell me that all drugs are found with NIH grants, and that drug companies hardly do any research. (I know that this sounds like the most ridiculous strawman, but believe me, there are people - who regard themselves as intelligent and informed - who believe this passionately, in nearly those exact words). But fear not, this isn't going to be a relentless pharma-is-great post, because it's certainly not a pharma-is-great paper. Read on. . .

Now to the qualitative rankings. The author used FDA priority reviews as a proxy for unmet medical need, but the scientific innovation rating was done basically by hand, evaluating both a drug's mechanism of action and how much its structure differed from what had come before. Just under half (123) of the drugs during this period were in for priority review, and of those, we have:

46% from pharmaceutical companies.
30% from biotech companies.
23% from universities (transferred to either biotech or pharma).

That shows the biotech- and university-derived drugs outperforming when you look at things this way, which again seems about right to me. Note that this means that the majority of biotech submissions are priority reviews, and the majority of pharma drugs aren't. And now to innovation - 118 of the drugs during this period were considered to have scientific novelty (46%), and of those:

44% were from pharmaceutical companies.
25% were from biotech companies, and
31% were from universities (transferred to either biotech or pharma).

The university-derived drugs clearly outperform in this category. What this also means is that 65% of the pharma-derived drugs get classed as "not innovative", and that's worth another post all its own. Now, not all the university-derived drugs showed up as novel, either - but when you look closer, it turns out that the majority of the novel stuff from universities gets taken up by biotech companies rather than by pharma.

So why does this happen? This paper doesn't put it one word, but I will: money. It turns out that the novel therapies are disproportionately orphan drugs (which makes sense), and although there are a few orphan-drug blockbusters, most of them have lower sales. And indeed, the university-to-pharma drugs tend to have much higher sales than the university-to-biotech ones. The bigger drug companies are (as you'd expect) evaluating compounds on the basis of their commercial potential, which means what they can add to their existing portfolio. On the other hand, if you have no portfolio (or have only a small one) than any commercial prospect is worth a look. One hundred million dollars a year in revenue would be welcome news for a small company's first drug to market, whereas Pfizer wouldn't even notice it.

So (in my opinion) it's not that the big companies are averse to novel therapies. You can see them taking whacks at new mechanisms and unmet needs, but they tend to do it in the large-market indications - which I think may well be more likely to fail. That's due to two effects: if there are existing therapies in a therapeutic area, they probably represent the low-hanging fruit, biologically speaking, making later approaches harder (and giving them a higher bar to clear. And if there's no decent therapy at all in some big field, that probably means that none of the obvious approaches have worked at all, and that it's just a flat-out hard place to make progress. In the first category, I'm thinking of HDL-raising ideas in cardiovascular and PPAR alpha-gamma ligands for diabetes. In the second, there are CB1 antagonists for obesity and gamma-secretase inhibitors in Alzheimer's (and there are plenty more examples in each class). These would all have done new things in big markets, and they've all gone down in expensive flames. Small companies have certainly taken their cuts at these things, too, but they're disproportionately represented in smaller indications.

There's more interesting stuff in this paper, particularly on what regions of the world produce drugs and why. I'll blog about again, but this is plenty to discuss for now. The take-home so far? The great majority of drugs come from industry, but the industry is not homogeneous. Different companies are looking for different things, and the smaller ones are, other things being equal, more likely to push the envelope. More to come. . .

Comments (35) + TrackBacks (0) | Category: Academia (vs. Industry) | Business and Markets | Drug Development | Drug Industry History | Who Discovers and Why

October 19, 2010

Trusting the Medical Literature?

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Posted by Derek

How reliable is the medical literature, anyway? This profile of John Ioannidis at The Atlantic is food for thought. Ioannidis is the man behind the famous "Why Most Published Medical Findings Are False" paper a few years ago, and many others in the same vein.

The problems are many: publication bias (negative findings don't get written up and reported as often), confirmation bias, and desire to stand out/justify the time and money/get a grant renewal. And then there's good old lack of statistical power. Ioannidis and his colleagues have noted that far too many studies that appear in the medical journals are underpowered, statistically, relative to the claims made for them. The replication rates of such findings are not good.

Interestingly, drug research probably comes out of his analysis looking as good as anything can. A large confirmatory Phase III study is, as you'd hope, the sort of thing most likely to be correct, even given the financial considerations involved. Even then, though, you can't be completely sure - but contrast that with a lot of the headline-grabbing studies in nutrition or genomics, whose results are actually more likely to be false than true.

Ioannidis's rules from that PLoS Medicine paper are worth keeping in mind:

The smaller the studies conducted in a scientific field, the less likely the research findings are to be true.

The smaller the effect sizes in a scientific field, the less likely the research findings are to be true.

The greater the number and the lesser the selection of tested relationships in a scientific field, the less likely the research findings are to be true.

The greater the flexibility in designs, definitions, outcomes, and analytical modes in a scientific field, the less likely the research findings are to be true.

The greater the financial and other interests and prejudices in a scientific field, the less likely the research findings are to be true.

The hotter a scientific field (with more scientific teams involved), the less likely the research findings are to be true.

And although he's talking about the published literature, these things are well worth keeping in mind when you're looking at your own internal data in a drug discovery project. Some fraction of what you're seeing is wrong.

Comments (17) + TrackBacks (0) | Category: Clinical Trials | Drug Development | The Scientific Literature

October 6, 2010

Chemical Biology: Engineering Enzymes

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Posted by Derek

I mentioned directed evolution of enzymes the other day as an example of chemical biology that’s really having an industrial impact. A recent paper in Science from groups at Merck and Codexis really highlights this. The story they tell had been presented at conferences, and had impressed plenty of listeners, so it’s good to have it all in print.

It centers on a reaction that’s used to produce the diabetes therapy Januvia (sitagliptin). There’s a key chiral amine in the molecule, which had been produced by asymmetric hydrogenation of an enamine. On scale, though, that’s not such a great reaction. Hydrogenation itself isn’t the biggest problem, although if you could ditch a pressurized hydrogen step for something that can’t explode, that would be a plus. No, the real problem was that the selectivity wasn’t quite what it should be, and the downstream material was contaminated with traces of rhodium from the catalyst.

So they looked at using a transaminase enzyme instead. That’s a good idea, because transaminases are one of those enzyme classes that do something that we organic chemists generally can’t usually do very well – in this case, change a ketone to a chiral amino group in one step. (It takes another amine and oxidizes that on the other side of the reaction). We’ve got chiral reductions of imines and enamines, true, but those almost always need a lot of fiddling around for catalysts and conditions (and, as in this case, can cause their own problems even when they work). And going straight to a primary amine can be, in any case, one of the more difficult transformations. Ammonia itself isn’t too reactive, and you don’t have much of a steric handle to work with.
sitagliptan%20rxn.png

But transaminases have their idiosyncracies (all enzymes do). They generally only will accept methyl ketones as substrates, and that’s what these folks found when they screened all the commercially available enzymes. Looking over the structure (well, a homology model of the structure) of one of these (ATA-117), which would be expected to give the right stereochemistry if it could be made to give anything whatsoever, gave some clues. There’s a large binding pocket on one side of the ketone, which still wasn’t quite large enough for the sitagliptin intermediate, and a small site on the other side, which definitely wasn’t going to take much more than a methyl group.

They went after the large binding pocket first. A less bulky version of the desired substrate (which had been turned, for now, into a methyl ketone) showed only 4% conversion with the starting enzymes. Mutating the various amino acids that looked important for large-pocket binding gave some hope. Changing a serine to phenylalanine, for example, cranked up the activity by 11-fold. The other four positions were, as the paper said, “subjected to saturation mutagenesis”, and they also produced a combinatorial library of 216 multi-mutant variations.

Therein lies a tale. Think about the numbers here: according to the supplementary material for the paper, they varied twelve residues in the large binding pocket, with (say) twenty amino acid possibilities per. So you’ve got 240 enzyme variants to make and test. Not fun, but it’s doable if you really want to. But if you’re going to cover all the multi-mutant space, that’s twenty to the 12th, or over four quadrillion enzyme candidates. That’s not going to happen with any technology that I can easily picture right now. And you’re going to want to sample this space, because enzyme amino acid residues most certainly do affect each other. Note, too, that we haven’t even discussed the small pocket, which is going to have to be mutated, too .

So there’s got to be some way to cut this problem down to size, and that (to my mind) is one of the things that Codexis is selling. They didn’t, for example, get a darn thing out of the single-point-mutation experiments. But one member of a library of 216 multi-mutant enzymes showed the first activity toward the real sitagliptin ketone precursor. This one had three changes in the small pocket and that one P-for-S in the large, and identifying where to start looking for these is truly the hard part. It appears to have been done through first ruling out the things that were least likely to work at any given residue, followed by an awful lot of computational docking.

It’s not like they had the Wonder Enzyme just yet, although just getting anything to happen at all must have been quite a reason to celebrate. If you loaded two grams/liter of ketone, and put in enzyme at 10 grams/liter (yep, ten grams per liter, holy cow), you got a whopping 0.7% conversion in 24 hours. But as tiny as that is, it’s a huge step up from flat zero.

Next up was a program of several rounds of directed evolution. All the variants that had shown something useful were taken through a round of changes at other residues, and the best of these combinations were taken on further. That statement, while true, gives you no feel at all for what this stuff is like, though. There are passages like this in the experimental details:

At this point in evolution, numerous library strategies were employed and as beneficial mutations were identified they were added into combinatorial libraries. The entire binding pocket was subjected to saturation mutagenesis in round 3. At position 69, mutations TAS and C were improved over G. This is interesting in two aspects. First, V69A was an option in the small pocket combinatorial library, but was less beneficial than V69G. Second, G69T was improved (and found to be the most beneficial in the next
round) suggesting that something other than sterics is involved at this position as it was a Val in the starting enzyme. At position 137, Thr was found to be preferred over Ile. Random mutagenesis generated two of the mutations in the round 3 variant: S8P and G215C. S8P was shown to increase expression and G215C is a surface exposed mutation which may be important for stability. Mutations identified from homologous enzymes identified M94I in the dimer interface as a beneficial mutation. In subsequent rounds of evolution the same library strategies were repeated and expanded. Saturation mutagenesis of the secondary sphere identified L61Y, also at the dimer interface, as being beneficial. The repeated saturation mutagenesis of 136 and 137 identified Y136F and T137E as being improved.

There, that wasn’t so easy, was it? This should give you some idea of what it’s like to engineer an enzyme, and what it’s like to go up against a billion years of random mutation. And that’s just the beginning – they ended up doing ten rounds of mutations, and had to backtrack some along the way when some things that looked good turned out to dead-end later on. Changes were taken on to further rounds not only on the basis of increased turnover, but for improved temperature and pH stability, tolerance to DMSO co-solvent, and so on. They ended up, over the entire process, screening a total of 36,480 variations, which is a hell of a lot, but is absolutely infinitesmal compared to the total number of possibilities. Narrowing that down to something feasible is, as I say, what Codexis is selling here.

And what came out the other end? Well, recall that the known enzymes all had zero activity, so it’s kind of hard to calculate improvement from that. Comparing to the first mutant that showed anything at all, they ended up with something that was about 27,000 times better. This has 27 mutations from the original known enzyme, so it’s a rather different beast. The final enzyme runs in DMSO/water, at loadings up of to 250g/liter of starting material at 3 weight per cent enzyme loading, and turns isopropylamine into acetone while it’s converting the prositagliptin ketone to product. It is completely stereoselective (they’ve never seen the other amine), and needless to say involves no hydrogen tanks and furnishes material that is not laced with rhodium metal.

This is impressive stuff. You'll note, though, the rather large amount of grunt work that had to go into it, although keep in mind, the potential amount of grunt work would be more than the output of the entire human race. To date. Just for laughs, an exhaustive mutational analysis of twenty-seven positions would give you 1.3 times ten to the thirty-fifth possibilities to screen, and that's if you know already which twenty-seven positions you're going to want to look at. One microgram of each of them would give you the mass of about a hundred Earths, not counting the vials. Not happening.

Also note that this is the sort of thing that would only be done industrially, in an applied research project. Think about it: why else would anyone go to this amount of trouble? The principle would have been proven a lot earlier in the process, and the improvements even part of the way through still would have been startling enough to get your work published in any journal in the world and all your grants renewed. Academically, you'd have to be out of your mind to carry things to this extreme. But Merck needs to make sitagliptin, and needs a better way to do that, and is willing to pay a lot of money to accomplish that goal. This is the kind of research that can get done in this industry. More of this, please!

Comments (33) + TrackBacks (0) | Category: Biological News | Chemical Biology | Chemical News | Drug Development

September 16, 2010

Six Sigma in Drug Discovery? Part One - Are Chemists Too Individual?

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Posted by Derek

I had an interesting email about a 2009 paper in Drug Discovery Today that has some bearing on the "how much compound to submit" question, as well as several other areas. It's from a team at AstraZeneca, and covers their application of "Lean Six Sigma" to the drug discovery process. I didn't see it at the time, but The title probably made me skip over it even if I had.

I'll admit my biases up front: outside of its possible uses in sheer widget-production-line settings, I've tended to regard Six Sigma and its variants as a buzzword-driven cult. From what I've been able to see of it, it generates a huge number of meetings and exhortations from management, along with a blizzard of posters, slogans, and other detritus. On the other hand, it gives everyone responsible a feeling that they've Really Accomplished Something, which is what most of these managerial overhauls seem to deliver before - or in place of - anything concrete. There, I feel better already.

On the other hand, I am presumably a scientist, so I should be willing to be persuaded by evidence. And if sensible recommendations emerge, I probably shouldn't be so steamed up about the process used to arrive at them. So, what are the changes that the AZ team says that they made?

Well, first off is a realization that too much time was being spent early on in resynthesis. The group ended up recommending that every lead-optimization compound be submitted in at least a 30 to 35 mg batch. From my experience, that's definitely on the high side; a lot of people don't seem to produce that much. But according to the AZ people, it really does save you time in the long run.

A more controversial shift was in the way that chemistry teams work. Reflecting on the relationship between overall speed and the amount of work in progress, they came up with this:

Traditionally, chemists have worked alongside each other, each working on multiple target compounds independently from the other members in the team. Unless managed very carefully by the team leader, this model results in a large, and relatively invisible, amount of work in progress across a team of chemists. In order to reduce the lead time for each target, it was decided to introduce more cooperative team working, combined with actively restricting the work in progress. The key driver to achieve and sustain these two goals was the introduction of a visual planning system that enables control of work in progress and also facil-
itates work sharing across the team. Such a visual planning system also allows the team to keep track of ideas, arrival of starting materials, ongoing synthesis and compounds being purified. It also makes problems more readily recognizable when they do occur.

We have reflected on why chemistry teams have always been organized in such an individual-based way. We believe that a major factor lies in the education and training of chemists at universities, in particular at the doctoral and postdoctoral level, which is always focused on delivery of separate pieces of work by the students. This habit has then been maintained in the pharmaceutical industry even though team working, with chemists supporting each other in the delivery of compounds, would be beneficial and reduce synthesis lead times.

OK, that by itself is enough to run a big discussion here, so I think I'll split off the rest of the AZ ideas into another post or two. So, what do you think? Is the "You do your compounds and I'll do mine" style hurting productivity in drug research? Is the switch to something else desirable, or even possible? And if it is, has AstraZeneca really accomplished it, or do they just say that they have? (Nothing personal intended there - it's just that I've seen a lot of "Now we do everything differently!" presentations over the years. . .) After all, this paper is over a year old now, and presumably covers things that happened well before that. Is this how things really work at AZ? Let the discussion commence!

Comments (50) + TrackBacks (0) | Category: Drug Development | Life in the Drug Labs | Who Discovers and Why

August 25, 2010

GSK's Response to the Sirtuin Critics

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Posted by Derek

OK, time (finally) for the latest chapter in the GSK-Sirtris saga. (This is going to get fairly geeky, so feel free to skip ahead if you're not into enzymology). You'll recall from previous installments that Amgen and Pfizer, among others, had disputed whether the reported sirtuin compounds worked the way that had originally been reported. GSK has now published a paper in the Journal of Biological Chemistry to address those questions. How well does this clear things up? Let's take things in order:

Claim 1: Resveratrol is not a direct activator of SIRT1 activity (Amgen). Building on two 2005 papers, the Amgen team said that resveratrol, the prototype SIRT1 ligand, only works in that manner when the fluorescent peptide (Fluor de Lys) was used in the assay. This is due, they found, exclusively to the fluorophore on the peptide - it's an artifact of the assay conditions. Without it, no activation was seen with protein assays in vitro, nor in cell assays. Native substrates (p53-derived peptide and PGC-1alpha) show nothing.

GSK's response: This is true. They too, found that activation of SIRT1 depends on the structure of the substrate. Without the fluorescent label, no activation is seen.

Claim 2: Not only is this true for resveratrol, it's true for SRT1720, SRT2183, and SRT 1460 (Pfizer). The Pfizer team did a similar breakdown of the assay conditions, and found (through several biophysical methods) that the fluorophore is indeed the crucial element in the activity seen in these assays. And again, since that's an artificial tag, the Fluor de Lys-based assays can have nothing to do with real in vivo activity. Native substrates (p53-derived peptide, full-length p53, and acetyl CoA synthase 1) show nothing.

GSK's response: As above, activation of SIRT1 depends on the structure of the substrate. Without the fluorescent label, no activation is seen. SRT1460 and SRT1720 do indeed bind to the fluorescent peptide, but not to the unlabeled versions. Looking over a broader range of structures, some of them interact with the fluorophore, and some don't. There's no correlation between this affinity and a compound's ability to activate SIRT1.

A screen of 5,000 compounds in this class turned up three that actually do work with nonfluorescent peptide substrates (compounds 22, 23, and 24 in the paper). None of these have been previously disclosed. They, however, that even these still don't work when the peptide substrate lacks both the fluorescent tag and a biotin tag.

What's more, when these three compounds are tested on a p53-derived 20-mer peptide substrate, they actually inhibit acetylation, instead of enhancing it. Looking closer at a range of peptide substrates, SRT1460 and other compounds can also inhibit or enhance acetylation, depending on what peptide is being used. An allosteric mechanism could explain these results. It seems more likely that there are at least two specific sites on SIRT1 that can bind these compounds - the active site and an allosteric one. Thus there are several species in equilibrium, depending on whether these sites have substrate or small molecule bound to them, and on how this binding stabilizes or destabilizes particular pathways. In the real cell, this may all be part of various protein-protein interactions.

Claim 3: SRT1720 does not lower glucose in a high-fat-fed mouse model (Pfizer). Even though exposure of the drug was as reported previously, they saw no evidence (at 30 mg/kilo) of glucose lowering or of any increased mitochondrial function. These animals showed increased food intake and weight gain. The 100 mpk dose was not well tolerated, and killed some animals.

GSK's response: not addressed in this paper. It's an enzymology study only.

Claim 4: Resveratrol, SRT 1460, SRT1720, and SRT2183 are not selective (Pfizer). A screen of over 100 targets showed all of these compounds hitting multiple targets, with resvertrol itself showing the closest thing to a clean profile. None of them, say the Pfizer team, are suitable pharmacological tools.

GSK's response: not addressed in this paper. None of the newly disclosed compounds have selectivity data of this sort attached to them, either. I'd be very curious to know how they look, and I'd be very leery of attaching much importance to their behavior in living systems until that's been done.

The take-home: On the enzymology level, this new paper seems to be solid work. But it's the sort of solid work that should have been done around the time that GSK bought Sirtris, and not something appearing in 2010 in response to major attacks in the literature. The first main claim of those attacking papers is, in fact, absolutely true: the original Fluor de Lys assay is worthless for characterizing these compounds. What we learn from this paper is that the assay is worthless for even more complicated reasons than originally thought, and that the whole series of SRT compounds behaves in ways that were not apparent from the published work, to put it lightly.

As to the selectivity and in vivo effects of these compounds, Pfizer's gauntlet is still thrown down right where they left it. The fact that these compounds are so much harder to understand than was originally thought, even in well-controlled enzyme assays, makes me wonder how easy it will be to figure out the rest of the story. . .

Comments (35) + TrackBacks (0) | Category: Aging and Lifespan | Drug Assays | Drug Development

August 20, 2010

Going Hollywood

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Posted by Derek

A reader at one of the big pharma companies sends along this note:

. . .Over my 10 years or so of experience, I have seen a severe decline in risk tolerance at my company, and other large companies as well. When we put a project forward, we are told that either: (a) There are too many unknowns, the target is not well established, and therefore the risk in putting forward the large sums of money required for development are too high; or (b) There are too many other players in the market already and we would never be able to capture enough market share to justify the investment required to go forward. The band considered acceptable in the risk/benefit spectrum has become so narrow that it is like threading a needle with your feet.

I believe that this risk aversion is due to the escalating cost of developing new drugs. Big Pharma has invested such a tremendous amount of money into the infrastructure they deemed necessary to increase project turnaround time that any drug that hoes forward has to be seen as a guaranteed blockbuster or it is considered a failure.

Film buff that I am, I use a Big Studio Production vs. Independent Film analogy when I discuss this with people outside the profession. For example, the film Avatar cost about 300 million to make. That means that if it brings in a mere 50 million in ticket sales, it is a catastrophic failure for the studio. Paranormal Activity on the other hand cost a few tens of thousands of dollars to make. Bringing in 50 million dollars in ticket sales would exceed the filmmakers wildest dreams of avarice.

The end result is that the Big Studio has to KNOW that Avatar will bring in greater than 300 million dollars in ticket sales or it cannot take the risk. Therefore only tried and true box office magic directors like James Cameron are given the opportunity to work at that level. On the other end of the spectrum, an independent film distribution company is willing to take on a high risk project like Paranormal Activity because even a failure will not destroy the comany, and the rewards of success (even if moderate by Big Studio standards) is very high.

So, has Big Pharma doomed itself by massively inflating its drug discovery infrastructure in a misguided attempt to stregnthed its pipeline (which was clearly a failure)? Or is it the regulatory agencies that require such vast and expensive trials that are the cause of this risk aversion? Is there a solution?

Well, the Hollywood analogy has been made before, but that's because it's a pretty good one. There are a few places where it breaks down, though. Some of these are unfavorable to the drug business:

1. Copyright. It lasts a lot longer than patent rights. I think that copyright has been extended to ridiculous levels in the US, but it's always been significantly longer than patent terms. So a studio has a much longer time to makes its money back.

2. Regulatory affairs. There's no FDA approval process for a new film. You think it up, you get it shot and produced, you release it, and good luck to you. The drug industry hasn't worked that way since the 1930s.

3. Cycle time. It takes a lot longer to get a drug project through than it takes to get a movie done. And since time is most definitely money, this hurts.

4. Toxicity and liability. While it's true that a bad film might make you feel sick, it's not going to lead to anything actionable in court. Bad news on a new drug's side effects or performance most definitely will, though. And how.

5. Costs and benefits. A movie, from the consumer's standpoint, is a momentary purchase, made with a small amount of discretionary income. If it delivers, great - if not, no harm done, other than some wasted time and a bit of cash. Drugs, of course, are a much more high-stakes business, both in their pricing and in their utility. And they affect a person's health, which is about as fundamental a thing as you can mess with, and moves any transaction up into a whole new spotlight.

On the other hand, there are some problems that the studios face that we don't:

1. Limits of copyright. While copyright goes on next to forever, it's still easy to move a new film or book right up next to an existing work. Movies get ripped off much more quickly than drugs can be, and often more blatantly. That shorter cycle time cuts both ways.

2. Easier copying. You can find pirated versions of first-run movies pretty quickly - they're not always great, but there's a market. Lots of free stuff gets tossed around in digital formats, too. Drugs are much harder to truly copy, and an inferior version is much, much less attractive.

3. Fashion. An antihypertensive drug from thirty years ago doesn't wear funny-looking retro clothes or pick up a mobile phone the size of a loaf of bread. It lowers your blood pressure, same as always. There may be better ones around now, but it'll still work exactly as it did when it came on the market.

All that said, I think that the key point here is that there's no equivalent in the drug industry to indie filmmaking, which is too bad. Our fixed costs are much, much, higher due to the field we operate in - human health and the regulations around it. My question is - is there any way to bring these down? Of course, that's what everyone in the business has been asking for some time now.

Because if we can't, we're going to see even more of the behavior that my correspondent noted. Risk aversion, I might add, can be fatal to research-driven companies. Our whole business is founded on taking risks, and if the costs are pushing us to deny that, we have a huge conflict right at the center of the whole enterprise. . .

And yeah, I realize that this doesn't help too much with the "less depressing" promise I made for this week!

Comments (36) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Drug Prices | Regulatory Affairs

August 16, 2010

Cancer Cells: Too Unstable For Fine Targeting?

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Posted by Derek

The topic of new drugs for cancer has come up repeatedly around here - and naturally enough, considering how big a focus it is for the industry. Most forms of cancer are the very definition of "unmet medical need", and the field has plenty of possible drug targets to address.

But we've been addressing many of them in recent years, with incremental (but only rarely dramatic) progress. It's quite possible that this is what we're going to see - small improvements that gradually add up, with no big leaps. If the alternative is no improvement at all, I'll gladly take that. But some other therapeutic areas have perhaps made us expect more. Infectious disease, for example: the early antibiotics looked like magic, as patients that everyone fully expected to die started asking when dinner was and when they could go home. That's what everyone wants to see, in every disease, and having seen it (even fleetingly), we all want to have it happen again.

And it has happened for a few tumor types, most notably childhood leukemia. But we definitely need to add more to the list, and it's been a frustrating business. Believe me, it's not like we in the business aiming for incremental improvements, a few weeks or months here and there. Every time we go after a new target in oncology, we hope that this one is going to be - for some sort of cancer - the thing that completely knocks it down.

We may be thinking about this the wrong way, though. For many years now, there have been people looking at genetic instability in tumor cells. (See this post from 2002 - yes, this blog has been around that long!) If this is a major component of the cancerous phenotype, it means that we could well have trouble with a target-by-target approach. (See this post by Robert Langreth at Forbes for a more recent take). And here's a PubMed search - as you can see, there's a lot of literature in this field, and a fair amount of controversy, too.

That would, in fact, mean that cancer shares something with infectious disease, and not, unfortunately, the era of the 1940s when the bacteria hadn't figured out what we could do to them yet. No, what it might mean is that many tumors might be made of such heterogeneous, constantly mutating cells that no one targeted approach will have a good chance of knocking them down sufficiently. Since that's exactly what we see, this is a hypothesis worth taking seriously.

There are other implications for drug discovery. Anyone who's worked in oncology knows that the animal tumor models we tend to use - xenografts of human cell lines - are not particularly predictive of success. "Necessary but nowhere near sufficient" is about as far as I'd be willing to go. Could that be because these cells, however vigorously they grow, have lost (or never had) that rogue instability that makes the wild-type tumors so hard to fight? I haven't seen a study of genetic instability in these tumor lines, but it would be worth checking.

What we might need, then, are better animal models to start with - here's a review on some efforts to find them. From a drug discovery perspective, we might want to spend more time on oncology targets that work outside the cancer cells themselves. And clinically, we might want to spend more time studying combinations of agents right from the start, and less on single-drug-versus-standard-of-care studies. The disadvantage there is that it can be hard to know where to start - but we need to weigh that against the chances of a single agent actually working

Comments (50) + TrackBacks (0) | Category: Animal Testing | Cancer | Clinical Trials | Drug Development

July 29, 2010

Open-Source Pharmaceutical Babble

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Posted by Derek

The topic of "open-source" drug discovery is an interesting (and potentially important) one. It just keeps coming up, but one of the problems with it is that it presents a terrible opportunity for vagueness. Too much of what I've read on the subject is hand-waving.

I'm afraid that the key parts of this column fall into the same category. It's by Jackie Hunter, formerly of GlaxoSmithKline. The lead-up parts of the piece are fine, where she lays out some of the problems facing the industry. But then we get this vision:

In the future, the most effective pharmaceutical companies will be hubs at the center of a network of collaborators and suppliers, focusing internally on their core competencies, which might include medicinal chemistry, execution of clinical trials, or sales and marketing. They will facilitate interactions across their network to stimulate the development of innovation ecosystems.

The resulting opportunities to expand beyond traditional products and markets will enable pharmaceutical companies to evolve into companies that offer a range of health-care solutions. These will include not only prescription medicines, but also diagnostics, branded generics, and technologies that support personalized medicine, as well as so-called “neutraceuticals” and other “wellness options.”

And that's it; that's the payoff. We'll all just hop to it, enabling and facilitating, expanding and evolving, stimulating and focusing. None of those are concrete verbs suggesting real courses of action. Whenever you see someone slip into that sort of talk, you can be sure that (at the very least) they have difficulty communicating whatever specific ideas they have. Or (more likely) that they don't have any specific ideas to tell you about at all.

Not that I can blame Jackie Hunter. I don't have a lot of good suggestions at the moment, either. But if you read that column closely, it says (on the one hand) that the problems of the industry are so large that single drug companies probably can't deal with them. Fine. Then it goes on to say that dealing with them will probably reduce the size of drug company R&D organizations. The connection between those two ideas is presumably hidden in that ball of fuzz I quoted above.

Comments (34) + TrackBacks (0) | Category: Drug Development | Drug Industry History

June 24, 2010

Fungal Structures to the Rescue

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Posted by Derek

From the Wall Street Journal, here's the history of the Novartis compound fingolimod, from its intellectual origins as a cicada fungus extract to today, when it might become the first oral medication for multiple sclerosis.

If fingolimod makes it, it'll also be the first drug I'm aware of that has a flippin' n-octyl chain hanging off it - a flagrant violation of everything that a medicinal chemist learns in their first month on the job. Hydrophobic bulk, metabolism bait, entropic penalty - well, there it is. I'm not suggesting that we all go out and slap pennzoilane and crisco-cene side chains on our lead drug candidates, but it's worth remembering that the race is not always to the swift, nor the battle to the strong.

Comments (29) + TrackBacks (0) | Category: Drug Development

June 23, 2010

Exelixis Gets a Compound Back

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Posted by Derek

Exelixis has long been a bit of a puzzle to outside observers. The company has developed a number of clinical candidates in oncology (many of them kinase inhibitors, I believe). In fact, for a while there, they seemed to have developed more clinical candidates than a company that size should have been able to manage. It was a bit alarming to employees of larger companies in the area.

And figuring out what the structures of these things were wasn't so easy, either. I once had the unenviable assignment of trying to break down a stack of their patent applications to see if I could find the lead structure for one of their compounds, and after a week or so I had to concede. None of my usual tricks worked - untangling and charting out the synthetic pathways from the experimental section to see the common threads, looking for sudden upticks in the amounts of intermediates or final compounds being prepared, looking to see if some compounds had been more completely characterized than others, and so on. No, these folks had done a fine job of sweeping up after themselves, and over the years I've run into other people who came to the same conclusion.

The company has had a long relationship with Bristol-Myers Squibb. There have been many twists and turns, but in 2008 the companies agreed to develop a compound called XL-139. (You won't quite be able to figure it out from that Exelixis page, but that announcement also marked the end of one of the broader agreements that the two companies had signed). Later that year came an announcement (also on that link above) about two more kinase inhibitors, XL-184 and XL-281, whose status hadn't been resolved earlier.

Now comes word that XL-184 has been returned to Exelixis. The press release, as press releases will, makes it seem as if the problem was that the compound was just too darn good:

"Given the recent progress of BMS' wholly-owned oncology pipeline and positive data generated by XL184, Exelixis and BMS were not able to align on the scope, breadth and pace of the ongoing clinical development of XL184."

They say that they're pleased to have the chance to develop the compound outside the meddling influence of BMS (well, not quite in those words naturally). But I'll bet they're not pleased to have to do it without BMS cash. Having the drug sent back makes you think that the larger company put it in the category of "Nothing we can't live without", although it's true that XL-184 is surely worth more to Exelixis. (Development of the other compound, XL-281, is apparently continuing).

My guess is that kinase inhibitors of this sort just look a lot less attractive than they did a few years ago. Several of them have made it to market, and while they can be profitable, the field is getting crowded. Mind you, they're all different from each other, but sorting out what works in the clinic is a long process. None of them seem (so far) to do anything dramatic against the most common tumor types. (Here's a recent article on just that problem). What Exelixis will make of XL-184 remains a mystery, probably to them just as much as to anyone else.

Comments (13) + TrackBacks (0) | Category: Cancer | Drug Development

June 21, 2010

Flibanserin: Not a "Female Viagra" At All

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Posted by Derek

I haven't commented on the controversy over Boehringer Ingleheim's drug for female libido, flibanserin. An FDA advisory panel voted it down on Friday, and it wasn't close: 10-1 against whether the drug showed efficacy, and unanimously against its side effect profile. I really don't see how the drug is going to make it back from that kind of reception.

The press coverage of this compound has not been good. Far too many headlines have called it "Female Viagra", which is ridiculously off-base. Viagra, for its part, does absolutely nothing for the libido; it's plumbing, a pure cardiovascular effect. The assumption (a reasonable one, for many men) is that the desire is already there. Meanwhile, flibanserin is a central nervous system agent, affecting the mental state of sexual satisfaction, not any cardiovascular sequelae. The drugs are completely different.

And the FDA panel's problem (one of their problems) with the drug was that it doesn't seem to do much for desire, either. We can argue all day about whether low desire is a disease or not, but even if someone does want to do something about it, flibanserin doesn't seem to be the answer.

Boehringer is taking a lot of criticism for bringing the drug this far, actually. It was originally developed as an antidepressant, but during the trials reports came in of the sexual effects in female patients, so they repurposed it - taking the drug out of a crowded field and into completely new territory. You can admire that as showing flexibility, or you can worry that the company found a possible drug and then went shopping for a disease, with a willingness to invent one if it didn't quite exist.

I don't know where I stand on that latter point; I've no idea what the statistics are on low sexual desire as a problem (and I'm willing to bet that what numbers might exist have whopping error bars on them). But I think that we're not going to be revisiting this topic any time soon. The FDA panel officially encouraged Boehringer to continue research, but the vote tallies are not the sort of thing that would encourage anyone.

Comments (26) + TrackBacks (0) | Category: Drug Development | Regulatory Affairs | The Central Nervous System

June 18, 2010

The Economic Impact of the Genomic Revolution's Failure

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Posted by Derek

Here's something that oddly ties together the last couple of days of posting around here: the failure of the Human Genome Project to jump-start drug discovery as the "most significant economic event of the past decade". (Thanks to Jonathan Gitlin for the tip).

I have to say, I hadn't thought of it in those terms. My first thought is that this is a negative event, something that didn't happen, so it's pointless to speculate about what might have been. But the author, Mike Mandel, is also talking about the opportunity cost of all the genomics frenzy, which is a real consideration. That time and money could have been spent somewhere else, doing something more useful. Where would we be then?

I've wondered about that myself, having seen first-hand what happened. Many companies really did cut a deep notch in their development pipelines during that era, abandoning (to one degree or another) their traditional approaches while piling resources into the genomics gold rush. (The current economic environment is cutting a similar gouge into the list of start-up companies - many of the ones that "normally" should have formed during the last couple of years just haven't happened).

Mandel's larger point, though, is something I'm not so sure about. He's talking about all the manufacturing jobs that haven't been created by the basic research, holding that these are the ones with real economic effect. But even if the genomics era had been wildly successful, we wouldn't have seen manufacturing jobs picking up from it for some years - 2008, maybe? His charts, which tend to cover from the early 1990s to date, are reflecting other issues entirely.

Then the talk turns to balance of trade:

Now let’s turn to trade. China, India, and the rest of the developing countries sell the U.S. an increasingly diverse array of goods and services. What does the U.S. provide in return? There’s the usual list of suspects, such as commercial aircraft (which is increasingly drawing on parts made outside of the country). But they are not enough to avoid a huge trade deficit, even now.

The logical candidate for the next wave of U.S. exports should have been biotech products and knowledge. The U.S. is the acknowledged world leader; the research is expensive and lengthy; the production processes are complicated, delicate, require skilled technicians, and cannot be easily offshored. And the category–treatments to deal with major medical problems–is something that everyone wants.

But what happened? Without compelling new biotech products, the big pharma companies were “me-tooed” to death. In fact, pharma trade went from roughly balanced to a big deficit.

That's illustrated by another chart from 1994 on. But what it's showing isn't what he thinks it's showing. It illustrates the move to less costly manufacturing sites, which would have taken place whether genomics would have delivered or not. The only mitigating factor is that any big protein-based biologics would have had a better chance of being produced domestically, but production of all the small-molecule drugs that might have come out of the genomics frenzy would have migrated offshore just like everything else.

And what if the genomics revolution had delivered? We'd have a lot more drugs on the market, none of which would be selling cheaply, you can be sure - and there would be even more anxiety over the amount of our GDP going to health care. (Never mind that some of these drugs would, one hopes, be keeping people from going into even more expensive therapies later - people don't seem to pay attention to that, either). So overall, I take the point about opportunity cost. But his broader economic implications, as least as regards the US economy alone, don't seem to me to hold up.

Comments (26) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

June 8, 2010

The Atlantic Monthly on Drug Pipelines

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Posted by Derek

Here's a good piece from Megan McArdle on the pipeline problem in the drug industry. It'll be familiar ground to many readers of this blog (and not just because I was a source for the piece), but it's good to get the word out on these things to as wide an audience as possible.

Comments (16) + TrackBacks (0) | Category: Drug Development | Drug Industry History | Press Coverage

May 19, 2010

Another Set of Eyes

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Posted by Derek

Via Avik Roy at Forbes, there's news of a deal between Pfizer and Washington University at St. Louis. The company is giving the university "unprecedented access" to what they say is a list of more than 500 drugs and failed drug candidates, and letting them tear into them in an effort to find out what new uses there might be for both current and failed compounds.

“There are two realities in drug discovery,” explains Don Frail, chief scientific officer of Pfizer’s Indications Discovery Unit. “The majority of candidates tested in development do not give the desired result, yet those drugs that do succeed typically have multiple uses. By harnessing the scientific expertise at this leading academic medical center, the collaboration seeks to discover entirely new uses for these compounds in areas of high patient need that might otherwise be left undiscovered.”

Pfizer's paying Wash. U. $22.5 million as well, which will be well worth it if a single good repurposing idea comes out of the collaboration. Pfizer (or any large drug company) can run through twenty million dollars of expenses on its own without a qualm, so this deal should be no problem. These compounds seem to already have had a lot of work done on them, and will thus have a shorter path through development if something turns up.

I've no idea what the chances of that are, of course - probably not all that great, but it's impossible to be sure about that. I do like the idea of letting a completely different set of eyes go over things, though. One of the biggest problems in a large organization is group-think. People get convinced that something is a hot area because other people seem convinced that it's a hot area, and the same holds true for getting convinced that something's not worth working on.

Look at the way Pfizer convinced itself that Exubera (inhaled insulin) was going to be a huge success, when it was actually a major disaster. On a smaller scale, that sort of thing happens all the time, all over the industry. Projects and ideas rise and fall only partly on their scientific merit - the drug labs are still staffed by human beings, and we're susceptible to all the biases and errors that everyone else is. And it's not like the Washington U people won't have their own biases, but theirs will at least be different.

That brings me back to one of the many reasons that I don't like giant drug company mergers. I think that we need as many different sets of eyes looking at our problems as we can get. The more shots get taken, from all sorts of angles, the better the chance of hitting something. And a huge company, while it does have room for some differences inside it, tends to homogenize viewpoints. The One Big Project with its One Big Compound will get the resources for a given area in the end. It's like when a multiplex theater opens in a smaller town - they tell everyone that with 16 screens they'll be able to bring in movies that otherwise never would play there. But come July, all sixteen screens are probably showing Revenge of the MegaSequel Part II, just to make sure that one's starting every twenty minutes.

Comments (15) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Development

May 18, 2010

Biosimilars: Not So Dang Easy

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Posted by Derek

This post drew a lot of comments here about how the big companies are going after follow-on biologic drugs. As a late-2008 article put it:

Merck already has one FOB in clinical development: a pegylated erythropoietin for anemia similar to Amgen's Aranesp (darbapoetin alfa) called MK-2578, which is being developed using a sugar-modification technology the pharma obtained via its 2006 purchase of GlycoFi. The company hopes to launch its EPO product in dialysis and pre-dialysis patients with chronic kidney disease in 2012.

Clyburn declined to offer any sales projections for that product or the MBV unit in general, nor would he identify any of the other products or therapeutic areas Merck will attempt to develop. He said MBV will identify product candidates by looking at their value in the marketplace.

Good move to decline those speculations, because Merck just announced recently that they're discontinuing that whole Aranesp-oid project. The FDA made it clear that they'd expect a full human cardiovascular safety workup before approval, which appears to have thrown Merck's numbers off severely, as you might imagine.

There is, and continues to be, no easy way.

Comments (7) + TrackBacks (0) | Category: "Me Too" Drugs | Drug Development

May 10, 2010

Malcolm Gladwell on Synta and Oncology

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Posted by Derek

The folks at the New Yorker sent along this link to a new article by Malcolm Gladwell about Synta and their attempts to get elesclomol (STA-4783) to work as a melanoma therapy. (If you don't know how this one turns out, you might want to read the article before clicking on that second link).

Update: didn't realize that the full article was subscriber-only at the New Yorker site. Not sure if there's anything to be done about that, but I've dropped them a line. . .

Gladwell (an occasional reader of this blog) often takes some hits from experts in the fields he writes about, but after reading the article this morning, I think he's done a fine job of showing what drug discovery is like. His division between screening and rational drug design is a bit too sharply defined, to my eyes, but he gets all the important stuff right - namely, just how hard a business this is, how much luck is involved, and how much we don't know. Those are messages that a lot of people need to hear, and I hope that this piece helps get them out to a wide audience.

Comments (8) + TrackBacks (0) | Category: Cancer | Drug Development | Drug Industry History | Press Coverage

May 6, 2010

Perverse Incentives In Clinical Trials

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Posted by Derek

I came across an article from 2007 that I'd missed, and I'm willing to bet others have, too. It's on the sometimes perverse incentives in developing oncology drugs (although the points in it apply to many other fields as well. The author (Tony Fiorino) is an investor, not a researcher, and seems to be an exceptionally clear-headed one.

He notes that larger profitable companies have more of an incentive to be careful about what drug candidates they take into the clinic, since they're spending their own profits when they do so. Start-up companies, on the other hand, tend to get valued according to how many clinical candidates they have going, so their incentive is to push things along rather more. . .briskly. This will be a familiar phenomenon to many readers here - the topic has come up whenever we talk about some compound wiping out in Phase III after what looked like promising data:

"This factor often leads development-stage companies to make very poor assessments with their own product candidates and to radically misjudge their likelihood of success. Indeed, if the fortunes of the entire company depend on the fate of a single phase II compound, and the interests of those deciding whether or not to enter phase III are tied entirely to the ongoing viability of the company, it would hardly seem surprising that companies push forward with the development of drugs when to objective outside observers further development seems futile. Indeed the market is likely to punish correct decision making by development-stage biotechnology companies. Given a set of questionable phase II data, the stock price of a company would suffer far more if management concluded it would be improper to expend shareholder capital on a phase III program likely to fail than if management decided to forge ahead into phase III on the basis of some dubious, post hoc subgroup analyses."

Of course, when this article was written, the funding environment was more permissive than it is today - but it will surely go that way again, and anyway, when the money is tight, the pressures to fight for it are even stronger.

"Thus, market forces do not produce efficient drug development; at least for the biotechnology industry, they may actually hinder it. This is particularly true in oncology drug development, where a set of unique circumstances conspire to make drug development more difficult and increase the likelihood that drug candidates are advanced too quickly. Zia et al1 documented a high rate of phase III failures in oncology, even when the phase III protocol uses a regimen identical to what was used in phase II. In particular, the lack of reliable surrogate markers and the common practice of looking for response rates in single arm trials make phase II oncology trials unreliable.

Most troubling, in my view (which is admittedly the view of a battle-scarred skeptic), oncology clinical development programs often appear to be designed specifically not to provide insight into the likelihood of success in phase III. . ."

Remind you of any events of the last few years? Fiorino's only answer to these problems is to call for the oncology clinical community to be more skeptical when it comes to enrolling patients in Phase III trials. And that might help a bit, but in a better world, we'd be running better Phase IIs.

Comments (19) + TrackBacks (0) | Category: Business and Markets | Cancer | Clinical Trials | Drug Development

May 3, 2010

The Collapse of Complexity

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Posted by Derek

Here's something a bit out of our field, but it might be disturbingly relevant to the drug industry's current situation: Clay Shirky on the collapse of complex societies. He's drawing on Joseph Tainter's archaeological study of that name:

The answer he arrived at was that (these societies) hadn’t collapsed despite their cultural sophistication, they’d collapsed because of it. Subject to violent compression, Tainter’s story goes like this: a group of people, through a combination of social organization and environmental luck, finds itself with a surplus of resources. Managing this surplus makes society more complex—agriculture rewards mathematical skill, granaries require new forms of construction, and so on.

Early on, the marginal value of this complexity is positive—each additional bit of complexity more than pays for itself in improved output—but over time, the law of diminishing returns reduces the marginal value, until it disappears completely. At this point, any additional complexity is pure cost.

Tainter’s thesis is that when society’s elite members add one layer of bureaucracy or demand one tribute too many, they end up extracting all the value from their environment it is possible to extract and then some.

Readers who work in the industry - particularly those at the larger companies - will probably have just shivered a bit. To my mind, that's an eerily precise summation of what's gone wrong in some R&D organizations. Shirky talks about internet hosting companies and the current dilemmas of the large media organizations, but there's plenty of room to include the drug industry in there, too. Look at the way research has been conducted over the past thirty years or so: we keep adding layers of complexity, basically because we have to - more and more assays and screens. It used to be (so I hear) all about dosing animals. Then you had cell cultures, then cloned receptors and enzymes came along (we're heading out of the 1970s and well into the 1980s now, if you're keeping score at home). Outside of target assays, the Ames test came along in the 1970s, and there were liver microsomes and isolated P450 enzymes for stability, Caco-2 cells for permeability, hERG assays to look out for cardiac tox, et cetera. You can do the same thing for the development of animal models - normal rodents, then natural inbred mutations, then knockouts, humanized transgenics. . .you get the picture.

As I say, we have very little choice but to get more complicated, because our knowledge of biology keeps expanding. But while this is going on, everyone keeps thinking that all this new knowledge is (at some point) going to start making things easier - a future era known, informally, as "when we really start figuring all this stuff out". It hasn't happened yet. If you're someone like Ray Kurzweil, you expect this pretty soon. I don't, although I hold out eventual long-term hope.

Shirky's message for the media companies is that their high-value-added lifestyles are being fatally undermined. We're not facing the same situation in this industry - there's no equivalent of free YouTube stuff eating our lunch, and I'm not expecting anything in that line for a long time, if ever. But the complexity-piling-on-complexity problem is real for us, nonetheless. If the burden gets too heavy, we could be in trouble even without someone coming along to push us over.

Comments (35) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

April 30, 2010

Rosetta@Home

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Posted by Derek

Many readers will have heard of Rosetta@Home. It's a distributed-computing approach to protein folding problems, which is certainly an area that can absorb all the floating-point operations you can throw at it. It's run from David Baker's lab at the University of Washington, and has users all over the world contributing.

A reader sends along news that recently the project seems to have come across a good hit in one of their areas, proteins designed to bind to the surface of influenza viruses. It looks like they have one with tight binding to an area of the virus associated with cell entry, so the next step will be to see if this actually prevents viral infection in a cell assay.

At that point, though, I have to step in as a medicinal chemist and ask what the next step after that could be. It won't be easy to turn that into any sort of therapy, as Prof. Baker makes clear himself:

Being able to rapidly design proteins which bind to and neutralize viruses and other pathogens would definitely be a significant step towards being able to control future epidemics. However, in itself it is not a complete solution because there is a problem in making enough of the designed proteins to give to people--each person would need a lot of protein and there are lots of people!

We are also working on designing new vaccines, but the flu virus binder is not a vaccine, it is a virus blocker. Vaccines work by mimicking the virus so your body makes antibodies in advance that can then neutralize the virus if you get infected later. the designed protein, if you had enough of it, should block the flu virus from getting into your cells after you had been exposed; a vaccine cannot do this.

One additional problem is that the designed protein may elicit an antibody response from people who are treated with it. in this case, it could be a one time treatment but not used chronically.

The immune response is definitely a concern, but that phrase "If you had enough of it" is probably the big sticking point. Most proteins don't fare so well when dosed systemically, and infectious disease therapies are notorious for needing whopping blood levels to be effective. At the same time, there's Fuzeon (enfuvirtide), a good-sized peptide drug (26 amino acids) against HIV cell entry. It was no picnic to develop, and its manufacturing was such an undertaking that it may have changed the whole industry, but it is out there.

My guess is that Rosetta@Home is more likely to make a contribution to our knowledge of protein folding, which could be broadly useful. More specifically, I'd think that vaccine design would be a more specific place that the project could come up with something of clinical interest. These sorts of proteins, though, probably have the lowest probability of success. The best I can see coming out of them is more insight into protein-protein interfaces - which is not trivial, for sure, but it's not the next thing to an active drug, either.

Comments (9) + TrackBacks (0) | Category: Biological News | Drug Development | Infectious Diseases

April 28, 2010

Pfizer's Future: Biotech Followups

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Posted by Derek

The Wall Street Journal has an article detailing some of Pfizer's plans in the biologics area: stepping in with second-generation versions of current winners from other companies. New versions of Rituxan and Enbrel are in the works, with the improvements mostly coming in how often the drugs need to be given.

They're not alone in this - Merck has announced that they're going to go after the same sorts of markets. And I can see the business rationale, since the original products have been such huge successes. But these new versions are going to be different enough that they're certainly not "biosimilars" or "biogenerics" - they're new substances, which will require their own complete safety/efficacy clinical workup. And by the time they get to market, some of these may be up against (or close to being up against) lower-cost versions of the original therapies, so the insurance companies are going to have to see some real benefit before they switch away.

So while some of these may well work out, not all of them will. It looks like a worthwhile thing to try, but it's not a sure road to riches. That's the thing about this industry these days - all those roads appear to be blocked off and plastered with "Detour" signs. . .

Comments (25) + TrackBacks (0) | Category: "Me Too" Drugs | Drug Development | Drug Prices

April 26, 2010

Charles River Buys WuXi

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Posted by Derek

I don't think we saw this one coming: Charles River Labs has announced that they're buying WuXi PharmaTech. They're paying about a 28% premium over Friday's closing stock price - Charles River's CEO will stay on, and WuXi's founder (Li Ge) will serve as executive VP under him.

Charles River, which is strong in the animal-testing end of the business, has apparently decided that Wu Xi is one of their biggest competitors (I'd agree) and has decided to try to stake out a leading position in the whole contract-research space. It's interesting to me that the folks at Wu Xi bought into this reasoning as well, although (since they're a publicly traded company here in the US), a lucrative stock offer can be its own argument. One now wonders, though, about the company's statements on re-staffing some of their US labs when economic conditions improve. . .

Comments (15) + TrackBacks (0) | Category: Animal Testing | Business and Markets | Drug Assays | Drug Development

April 16, 2010

A Landmark In Clinical Trial Data Interpretation

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Posted by Derek

You know, let's just declare this "Sketchy Biotech Day" around here. A reader sends along this intriguing news item from Maryland regarding Rexahn Pharmaceuticals. They recently reported clinical data on their lead compound, Serdaxin,:

On Tuesday, the Rockville company reported the drug performed well in a phase 2a clinical trial for treating patients with one such ailment: major depressive disorder. But the announcement also said "the overall study did not achieve statistical significance," worrying investors and sending Rexahn's stock price tumbling from $3.53 to $1.76 that day.

Wednesday morning, executives felt compelled to issue a follow-up statement, offering "additional commentary, clarifications and insights" to allay investors' concerns. That apparently did the trick — at least somewhat. By the end of trading on Wednesday, the price had rebounded to $2.15. By Thursday morning, shares had climbed to $2.51; they were trading at $2.47 Thursday afternoon.

In its initial statement, Rexahn said that results from the trial, which enrolled 77 patients at several sites in the U.S., "are compelling and warrant further study in a larger phase 2 trial."

Well, to me, "compelling" clinical trial numbers are a hard thing to sell without the statistics to back them up. But that's not slowing these folks down. Here I offer you what is perhaps the most breathtaking rationalization I have yet heard about drug development - and mind you, that is saying a lot. Says Rexahn's CEO:

"Based on the feedback and reaction from our shareholders, stakeholders and other market participants, it is clear that neither the purpose of the Serdaxin trial or its results were well understood.

"The purpose of the Serdaxin Phase IIa trial was to establish, as a proof of concept, that Serdaxin can work as an antidepressant drug for patients suffering from Major Depressive Disorder," Ahn said. "I am happy to say that this is exactly what the study accomplished. The trial results unambiguously reach the conclusion that patients, especially those suffering from severe depression, respond positively to Serdaxin.

"Some market participants have asked us why our overall trial results were not statistically significant," he said. "The answer is simply that the Serdaxin study was never designed to achieve statistical significance as a primary objective, but rather to establish a positive signal among treated patients. This is exactly what the trial succeeded in accomplishing."

So here you have it: a clinical trial that was, apparently, not designed to show statistical significance. And it didn't! Champagne for everyone! Think of how many other drugs have had results just this compelling, but we've all just been too stupid to realize what we had. Throw open the pharma mausoleums and let the dead compounds come forth!

Perhaps some day we'll all look back on this event as the Day the Drug Industry Changed Forever. Or perhaps it's time to ask just what Serdaxin is. . .well, you'll never guess. It's clavulanic acid. (See, I told you that you wouldn't get it). Yep, the beta-lactamase inhibitor that's given as part of Augmentin, to overcome resistant strains of bacteria. Weirdly, it does seem to penetrate the blood-brain barrier, which is not something I would have guessed. And the Rexahn people have done some animal studies that suggest it has anxiolytic effects (as well as effects on sexual arousal, which they're not ignoring: that, friends, is the drug development candidate Zoraxel on their web site. Still clavulanic acid, though, but a rose by any other name. . .).

But none of that means a thing unless you achieve results in humans. And though I hate to contradict such a visionary mind as Dr. Ahn's, I'm afraid I'm going to have to hold out for statistical significance. And wonder, in the meantime, if any of the zillions of people who've taken clavulanate before ever noticed any elevation in their mood. Never happened to me, that's for sure. . .

Comments (54) + TrackBacks (0) | Category: Clinical Trials | Drug Development | Infectious Diseases | The Central Nervous System

April 7, 2010

Pfizer's Golden Age

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Posted by Derek

I'm not sure I'd use this sort of language myself, but here we go: Pfizer's Martin Mackay is telling Bloomberg that the company is in a "golden age of drug discovery".

As of the end of last year, Pfizer had 26 drugs in phase-three trials. . .compared with eight at the end of 2007, Mackay said. That doesn’t include the treatments it got from Wyeth, he said at a briefing at the company’s research unit in Singapore.

Following the acquisition, Pfizer cut its research portfolio to 500 projects from 600, as it focuses on accelerating the development of drugs with a “big, early” effect in patient studies while weeding out the losers earlier in the process, Mackay said.

He says that Pfizer's pipeline is basically just running over with candidates in cancer, Alzheimer’s, pain, inflammation, and infectious diseases. And I've been hearing for years and years about weeding out the losing compounds earlier in the process, but as far as I can see, Phase III failures are either the same or going up as a share of total clinical dropouts.

At any rate, these assertions are subject to proof. For the sake of the patients that these drugs could help, and for the sake of Pfizer's patient shareholders, I hope that this golden-age talk is right. But there are a lot of ex-Pfizer people out there who have reasons of their own to dispute the statement.

Comments (37) + TrackBacks (0) | Category: Business and Markets | Drug Development

March 24, 2010

Drugs And Their Starting Points

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Posted by Derek

I've spoken about fragment-based drug design and ligand efficiency here a few times. There's a new paper in J. Med. Chem. that puts some numbers on that latter concept. (Full disclosure - I've worked with its author, although I had nothing to do with this particular paper).

For the non-chemists in the crowd who want to know what I'm talking about, fragment-based methods are an attempt to start with smaller, weaker-binding chemical structures than we usually work with. But if you look at how much affinity you're getting for the size of the molecules, you find that some of these seemingly weaker compounds are actually doing a great job for their size. Starting from these and building out, with an eye along the way toward keeping that efficiency up, could be a way of making better final compounds than you'd get by starting from something larger.

Looking over a number of examples where the starting compounds can be compared to the final drugs (not a trivial data set to assemble, by the way), this work finds that drugs, compared to their corresponding leads, tend to have similar to slightly higher binding efficiencies, although there's a lot of variability. They also tend to have similar logP values, which is a finding that doesn't square with some previous analyses (which showed things getting worse during development). But drugs are almost invariably larger than their starting points, so no matter what, one of the keys is not to make the compounds greasier as you add molecular weight. (My "no naphthyls" rule comes from this, actually).

There are a few examples of notably poor ligand-efficient starting structures that have nonetheless been developed into drugs. Interestingly, several of these are the HIV protease inhibitors, with Reyataz (atazanavir) coming in as the least ligand-efficient drug in the whole data set. A look at its structure will suffice. The wildest one on the list appears to be no-longer-marketed amprenavir, whose original lead was 53 micromolar and weighed over 600, nasty numbers indeed. I would not recommend emulating that one. In case you're wondering, the most ligand efficient drug in the set is Chantix (varenicline).

In the cases where ligand efficiency actually went down along the optimization route, inspection of the final structures shows that in many cases, the discovery team was trading efficiency for some other property (PK, solubility, etc.) To me, that's another good argument to make things as efficient as you can, because that gives you something to trade. A big, chunky, lashed-together structure doesn't give you much room to maneuver.

Comments (28) + TrackBacks (0) | Category: Drug Assays | Drug Development

January 29, 2010

Merck and Sirna

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Posted by Derek

Xconomy has a look inside the Merck-Sirna acquisition, an interview with Merck's head of that area. As you'd guess, he emphasizes that one of the biggest challenges in the field is delivery, and he makes the pitch that this is how Merck is going to make this work out:

What you often read about, but many people don’t understand, is how hard it is to make a drug. Our approach to RNA Therapeutics is made with a recognition of the full package it takes to launch a successful commercial product. . .That’s versus another strategy you see from smaller companies, which is to get an interesting experimental result, and publicly disclose it in an attempt to increase the value of your investment or a VC’s investment, without a real [awareness] of what it will take to make a therapeutic eight years later. . .

We immediately, after the acquisition, invested not just heavily in the RNA piece that is here in San Francisco, but we built an entire delivery group in West Point, PA. The thing that continues to differentiate Merck is that we have people with decades of experience in pharma R&D, drug safety, metabolism, pharmacokinetics. . .

Outside of RNA as a therapy in itself, he also talks about Merck's use of the technology to better understand its small-molecule targets. It's not something that you'll ever see press releases about, but trustworthy data of that sort is very useful and important. As the Xconomy interviewer notes, Wall Street values this sort of thing as basically zero (partly because you can't see the results of it for quite a while, if they're ever made public at all), but the value inside the company can be significant.

Of course, there can be things that happen inside drug companies that significantly destroy value, too, and it's not like the stock market can see (or understand) many of those, either, but that's a topic for another post entirely. . .and on a not perhaps unrelated note, one part of the interview above seems to suggest that "POS" is an internal Merck acronym for. . .wait for it. . ."probability of success". I, uh, kid you not.

Comments (7) + TrackBacks (0) | Category: Business and Markets | Drug Assays | Drug Development

January 15, 2010

Sirtuin Scenarios

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Posted by Derek

So, after reading what Pfizer has to say about Sirtris (and by extension, about GlaxoSmithKline's heavy investment in them), let's go over the possibilities. What happened, and what's going on?

We'll start out with the first branch point: either Pfizer (and Amgen) are right that there's trouble with the Sirtris assays and compounds (Reality A, I'll call it), or they're wrong (Reality B). For the rest of this piece, I'm going to assume that they're right, because I think that this is almost certainly the case. At least two separate groups of competent investigators have reported trouble, and that's good enough for me. (We'll discuss the implications of that in a bit).

Now we come to the second branch point: either Glaxo did enough due diligence to be aware of the problems (scenario A1) or they didn't realize them at the time of the deal (scenario A2). If A1 is the case, then we'd have to assume that the most likely consequence (A1a) is that Sirtris had other non-public assets that did check out, and that GSK's management felt that these justified the purchase. (A1b would be the scenario where GSK was well aware of the Sirtris problems, knew also that they didn't have anything else to offer, and bought them anyway, which doesn't make sense). These assets could have been other compounds, and/or a leg up on the complicated biology of this field. The difficulty with that line of thinking is that having found the fundamental assay problems with the Sirtris work, the GSK people would surely have been much more cautious about drawing sweeping conclusions about the rest of the company's intellectual property.

If A2 is the case, then we're looking at sheer fecklessness on the part of GSK's upper management. I'd like to be able to rule this out, but there have been other deals in the history of this industry that make that hard to do. I have witnessed at least one such personally. One problem is that these deals tend to be initiated near the highest levels of a company, and these people are not always the most technically savvy (or up-to-date) members of an organization. Even with a science background, the CEO of a large company does not have the time to be a scientist. (I'm reminded of Peter O'Toole's character in My Favorite Year: "I'm not an actor - I'm a movie star!"

Overall, though, I find it hard to believe that no one would have noticed the reported problems at all, which leads me to favor what I'll call scenario A3: the problems with the Sirtris assays may well have been known/realized at the lower scientific levels of GSK's organization, but these concerns may not have made it to the top in a sufficiently timely or vigorous manner. The deal would have gone through under its own momentum, then, in a flurry of last-minute misgivings which would have been hard to distinguish from the usual butterflies that accompany any large transaction or the preliminary stirrings of buyer's remorse. The sorts of reasons advanced in the A1 paragraph above would have been used to justify pushing ahead. With that in mind, this scenario could be broken down further into A3a, where Sirtris also had some other assets that the rest of us haven't seen, and A3b, where they didn't. I think that A3a is more likely, since that would have provided some of the momentum to get the deal done regardless. A3b is basically A2 with different timing and slightly less cluelessness.

So where do things go from here? That obviously depends on which of those three realities obtains. If A1 (specifically A1a) is the case, then GSK plows ahead with their secret Sirtris assets and compounds, and good luck to all concerned. It's worth keeping in mind that sirtuins are quite interesting and important, and that it's an area worth investigating on its own merits. (Pfizer and Amgen, among others, must think so too; that's the only reason that they would have been trying to replicate the Sirtris work).

If A2 is the real story, well, I'm very sorry to hear it. A lot of people seem ready to believe this one, partly because of anger over the layoffs the company has been going through. The most likely consequence of A2 is that $720 million dollars disappears, never to yield anything that's of use to anyone, so I hope that this isn't what happened.

And if, as I think, A3 is what actually happened, then that sort of depends on whether we're looking at A3a or A3b. If the former, then Glaxo overpaid, but has a fighting chance to redeem itself. If the latter, then Glaxo not only overpaid, but (as with A2) is in danger of losing its whole investment as well. We'll all find out.

But we may not find out very quickly. GSK has (like many other companies) a tendency to be rather close-mouthed about the progress of some of its research. When I worked in the nuclear receptor field, we all were very interested in the fate of a particular Glaxo compound, the first selective PPAR-delta ligand to go into the clinic. The company had talked about some animal and preclinical data, but we knew that they were taking it into humans (after all, it was listed that way in their pipeline updates). But it stayed listed like that. . .and stayed. . .and stayed. . .until, as the months and years passed, it became obvious to even the most optimistic observer that the compound's development was (at the very least) extremely complicated, and (more likely) had actually quietly ceased a good while before, albeit with no change in its public status.

In this case, now that these doubts have come up, GSK has a real interest in pointing out any success it may have. If its sirtuin compounds go into the clinic and just sort of hang there, that will probably be an even worse sign than usual. And if no sirtuin compounds even go into the clinic at all, well, the question has answered itself. I hope that's not what happens.

Comments (61) + TrackBacks (0) | Category: Aging and Lifespan | Clinical Trials | Diabetes and Obesity | Drug Development

December 14, 2009

The Cost of New Drugs

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Posted by Derek

I'm continuing my look at Bernard Munos' paper on the drug industry, which definitely repays further study (previous posts here, here, and here). Now for some talk about money - specifically, how much of it you'll need to find a new drug. The Munos paper has some interesting figures on this question, and the most striking figure is that the cost of getting a drug all the way to the market has been increasing at an annual rate of 13.4% since the 1950s. That's a notoriously tough figure to pin down, but it is striking that the various best estimates of the cost make an almost perfectly linear log plot over the years. We may usefully contrast that with the figures from PhRMA that indicate that large-company R&D spending has been growing at just over 12% per year since 1970. Looking at things from that standpoint, we've apparently gotten somewhat more efficient at what we do, since NME output has been pretty much linear over that time.

But that linear rate of production allows Munos to take a crack at a $/NME figure for each company on his list, and he finds that less than one-third of the industry has a cost per NME of under $1 billion dollars, and some of them are substantially more. Of course, not every NME is created equal, but you'd have to think that there are large potential for mismatches in development cost versus revenues when you're up at these levels. Munos also calculates that the chance of a new drug achieving blockbuster status is about 20%, and that these odds have also remained steady over the years - this despite the way that many companies try to skew their drug portfolios toward drugs that could sell at this level.

How much of these costs are due to regulatory burden? A lot, but for all the complaining that we in the industry do about the FDA, they may, in the long run, be doing us a favor. Citing these three studies, Munos says that:

. . .countries with a more demanding regulatory apparatus, such as the United States and the UK, have fostered a more innovative and competitive pharmaceutical industry. This is because exacting regulatory requirements force companies to be more selective in the compounds that they aim to bring to market. Conversely, countries with more permissive systems tend to produce drugs that may be successful in their home market, but are generally not sufficiently innovative to gain widespread approval and market acceptance elsewhere. This is consistent with studies indicating that, by making research more risky, stringent regulatory requirements actually stimulate R&D investment and promote the emergence of an industry that is research intensive, innovative, dominated by few companies and profitable.

But this still leaves us with a number of important variables that we don't seem to be able to push much further - success rates in the clinic and in the marketplace, money spent per new drug, and so on. And that brings up the last part of the paper, which we'll go into next time: what is to be done about all this?

Comments (17) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

December 11, 2009

Another Take on the Munos Paper

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Posted by Derek

Eric Milgram over at PharmaConduct has an excellent post up on the same paper I've been discussing this morning. As another guy who's been around the block a few times in this industry, he's struck by many of the same points I am (to the point of also linking to Wikepedia's page on Poisson distributions!)

And he has some interesting data of his own to present, too - well worth checking out.

Comments (12) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

Munos On Big Companies and Small Ones

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Posted by Derek

So that roughly linear production of new drugs by Pfizer, as shown in yesterday's chart, is not an anomaly. As the Bernard Munos article I've been talking about says:

Surprisingly, nothing that companies have done in the past 60 years has affected their rates of new-drug production: whether large or small, focused on small molecules or biologics, operating in the twenty-first century or in the 1950s, companies have produced NMEs at steady rates, usually well below one per year. This characteristic raises questions about the sustainability of the industry's R&D model, as costs per NME have soared into billions of dollars.

What he's found, actually, is the NME generation at drug companies seems to follow a Poisson distribution, which makes sense. This behavior is found for systems (like nuclear decay in a radioactive sample) where there are a large number of possible events, but where individual ones are rare (and not dependent on the others). A Poisson process also implies that there's some sort of underlying average rate, and that the process is stochastic - that is, not deterministic, but rather with a lot of underlying randomness. And that fits drug development pretty damned well, in my experience.

But that's just the sort of thing, as I've pointed out, that the business-trained side of the industry doesn't necessarily want to hear about. Modern management techniques are supposed to quantify and tame all that risky stuff, and give you a clear, rational path forward. Yeah, boy. The underlying business model of the drug industry, though, as with any fundamentally research-based industry, is much more like writing screenplays on spec or prospecting for gold. You can increase your chances of success, mostly by avoiding things that have been shown to actively decrease them, and you have to continually keep an eye out for new information that might help you out. But you most definitely need all the help you can get.

As that Pfizer chart helps make clear, Munos is particularly not a fan of the merge-your-way-to-success idea:

Another surprising finding is that companies that do essentially the same thing can have rates of NME output that differ widely. This suggests there are substantial differences in the ability of different companies to foster innovation. In this respect, the fact that the companies that have relied heavily on M&A tend to lag behind those that have not suggests that M&A are not an effective way to promote an innovation culture or remedy a deficit of innovation.

In fact, since the industry as a whole isn't producing noticeably more in the way of new drugs, he suggests that one possibility is that nothing we've done over the last 50 years has helped much. There's another explanation, though, that I'd like to throw out, and whether you think it's a more cheerful one is up to you: perhaps the rate of drug discovery would actually have declined otherwise, and we've managed to keep it steady? I can argue this one semi-plausibly both ways: you could say, very believably, that the progress in finding and understanding disease targets and mechanisms has been an underlying driver that should have kept drug discovery moving along. On the other hand, our understanding of toxicology and our increased emphasis on drug safety have kept a lot of things from coming to the market that certainly would have been approved thirty years ago. Is it just that these two tendencies have fought each other to a draw, leaving us with the straight lines Munos is seeing?

Another important point the paper brings up is that the output of new drugs correlates with the number of companies, better than with pretty much anything else. This fits my own opinions well (therefore I think highly of it): I've long held that the pharmaceutical business benefits from as many different approaches to problems as can be brought to bear. Since we most certainly haven't optimized our research and development processes, there are a lot of different ways to do things, and a lot of different ideas that might work. Twenty different competing companies are much more likely to explore this space than one company that's twenty times the size. Much of my loathing for the bigger-bigger-bigger business model comes from this conviction.

In fact, the Munos paper notes that the share of NMEs from smaller companies has been growing, partly because the ratio of big companies to smaller ones has changed (what with all the mergers on the big end and all the startups on the small end). He advances several other possible reasons for this:

It is too early to tell whether the trends of the past 10 years are artefacts or evidence of a more fundamental transformation of the drug innovation dynamics that have prevailed since 1950. Hypotheses to explain these trends, which could be tested in the future, include: first, that the NME output of small companies has increased as they have become more enmeshed in innovation networks; second, that large companies are making more detailed investigations into fundamental science, which stretch research and regulatory timelines; and third, that the heightened safety concerns of regulators affect large and small companies differently, perhaps because a substantial number of small firms are developing orphan drugs and/or drugs that are likely to gain priority review from the FDA owing to unmet medical needs.

He makes the point that each individual small company has a lower chance of delivering a drug, but as a group, they do a better job for the money than the equivalent large ones. In other words, economies of scale really don't seem to apply to the R&D part of the industry very well, despite what you might hear from people engaged in buying out other research organizations.

In other posts, I'll look at his detailed analysis of what mergers do, his take on the (escalating) costs of research, and other topics. This paper manages to hit a great number of topics that I cover here; I highly recommend it.

Comments (41) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Who Discovers and Why

December 10, 2009

Pfizer's R&D Productivity

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Posted by Derek

Courtesy of Bernard Munos, author of the Nature Reviews article that I began blogging about yesterday, comes this note about Pfizer's track record with new molecules. His list of Pfizer NMEs since 2000 is Geodon (ziprasidone, 2001), Vfend (voriconazole, 2002, from Vicuron - whoops, not so, this one's Pfizer's), Relpax (eletriptan, 2002), Somavert (pegvisomant, 2003, from Pharmacia & Upjohn), Lyrica (pregabalin, 2004, from Warner Lambert), Sutent (sunitinib, 2006, from Sugen/Pharmacia), Chantix (varenicline, 2006), Selzentry (maraviroc, 2007), and Toviaz (fesoterodine, 2008, from Schwarz Pharma). There are some good drugs on that list, but considering that even just five years ago, the company was claiming that it had 101 NMEs in development, and was going to file 20 NDAs by now, it might seem a bit thin.
Pfizer%20graph%20fixed.jpg

It might especially seem that way when you look over this graph, also provided by Munos (but not used in his recent article). You can see that Pfizer's R&D spending has nearly tripled since the year 2000, but that cumulative NME line doesn't seem to be bending much. And, as Munos points out, two (and now three) productive research organizations have been taken out along the way to produce these results. It is not, as they say, a pretty picture.

Comments (49) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

Selective Scaffolds

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Posted by Derek

We spend a lot of time in this business talking about molecular scaffolds - separate chemical cores that we elaborate into more advanced compounds. And there's no doubt that such things exist, but is part of the reason they exist just an outcome of the way chemical research is done? Some analysis in the past has suggested that chemical types get explored in a success-breeds-success fashion, so that the (over)representation of some scaffold might not mean that it has unique properties. It's just that it's done what's been asked of it, so people have stuck with it.

A new paper in J. Med. Chem. from a group in Bonn takes another look at this question. They're trying to see if the so-called "privileged substructures" really exist: chemotypes that have special selectivity for certain target classes. Digging through a public-domain database (BindingDB), they found about six thousand compounds with activity toward some 259 targets. Many of these compounds hit more than one target, as you'd expect, so there were about 18,000 interactions to work with.

Isolating structural scaffolds from the compound set and analyzing them for their selectivity showed some interesting trends. They divide the targets up into communities (kinases, serine proteases, and so on), and they definitely find community-selective scaffolds, which is certainly the experience of medicinal chemists. Inside these sets, various scaffolds also show tendencies for selectivity against individual members of the community. Digging through their supporting information, though, it appears that a good number of the most-selective scaffolds tend to come from the serine protease community (their number 3), with another big chunk coming from kinases (their number 1a). Strip those (and some adenosine receptor ligands and DPP inhibitors, numbers 11 and 8) out, and you've taken out all the really eye-catching selectivity numbers out of their supplementary table S5. So I'm not sure that they've identified as many hot structures as one might think.

Another problem I have, when I look at these structures, is that a great number of them look too large for any useful further development. That's just a function of the data this team had to start with, but this gets back to the question of "drug-like" versus "lead-like" structures. I have a feeling that too many of the compounds in the BindingDB set are in the former category, or even beyond, which skews things a bit. Looking at a publication on it from 2007, I get the impression that a majority of compounds in it have a molecular weight greater than 400, with a definite long tail toward the higher weights. What medicinal chemists would like, of course, is a set of smaller scaffolds that will give them a greater chance of landing in a selective chemical space that can be developed. Some of the structures in this paper qualify, but definitely not all of them. . .

Comments (6) + TrackBacks (0) | Category: Drug Assays | Drug Development | In Silico

December 3, 2009

All Of You Industrial Scientists: Out Of the Room

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Posted by Derek

Continuing Education (CE) is a big issue in many medical fields and those associated with them. Licensing boards and professional societies often require proof that people are keeping up with current developments and best practices, which is a worthy goal even if arguments develop over how well these systems work.

And it's also been a battleground for fights over commercial conflicts of interest. On the one hand, no one needs a situation where a room full of practitioners sits down to a blatant sales pitch that nonetheless counts as continuing education. But one the other hand, you have the problem that's now developing thanks to new policies by the Accreditation Council for Continuing Medical Education (ACCME) and the Accreditation Council for Pharmacy Education (ACPE). Thanks to a reader, I'm reproducing below some key parts of a letter that one professional organization, the American Society for Clinical Pharmacology and Therapeutics, has recently sent out to its members:

In 2006, ACCME and ACPE adopted new accreditation policies that went into effect in January 2009. Most concerning of these new policies is the requirement that CE providers develop activities/education interventions independent of any commercial interest, including presentation by industry scientists. This requirement greatly impacts the Society as industry scientists constitute nearly 50% of our membership and contribute significantly to the scientific programming of the ASCPT Annual Meeting. . .

ASCPT has been left with two options: 1) stop providing CE credit and continue to involve scientists from industry in the scientific program of the Annual Meeting; or 2) continue providing CE credit and remove all industry scientists from the program and planning process. . .

They go on to say that this year's meeting, having already been planned in the presence of Evil Industry Contaminators (well, they don't quite say it like that), will have no CE component, and that they don't see how they'll be able to have any such in the future, since they can't very well keep half the membership from presenting their work. This is definitely a problem for a number of professional organization, particularly the ones that deal with clinical research. They intersect with the professions that tend to have continuing education requirements, but a significant part of the expertise in their fields is found in industry. The ASCPT is not the only society facing this same dilemma.

It looks as if the accreditation groups decided that they were faced with a choice: commit themselves to judging what sorts of presentations should count for CE credit (which you might think was their job), or just toss out anything that has any connection with industry. That way you can look virtuous and save time, too. My apologies if I'm descending into ridicule here, but as an industrial scientist I find myself resenting the implication that my hands (and those of every single one of my colleagues) are automatically considered too dirty to educate any practicing professionals.

To be fair, this could well be one of those situations that the industry has helped bring on itself. I've no doubt that the CME process has probably been abused in the past. (Update: see the comments section. Am I being too delicate in this phrasing? Probably comes from never having dealt much with the marketing side of the business. . .) But there has to be some way to distinguish the old-fashioned "golf-resort meeting" from a clinical pharmacologist delivering a paper on new protocols for trial designs. The last thing we need is to split the scientific community even more than it's split already.

Comments (14) + TrackBacks (0) | Category: Academia (vs. Industry) | Clinical Trials | Drug Development

November 28, 2009

Recommended Books For Medicinal Chemists, Part One

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Posted by Derek

I asked recently for suggestions on the best books on med-chem topics, and a lot of good ideas came in via the comments and e-mail. Going over the list, the most recommended seem to be the following:

For general medicinal chemistry, you have Bob Rydzewski's Real World Drug Discovery: A Chemist's Guide to Biotech and Pharmaceutical Research. Many votes also were cast for Camille Wermuth's The Practice of Medicinal Chemistry. For getting up to speed, several readers recommend Graham Patrick's An Introduction to Medicinal Chemistry. And an older text that has some fans is Richard Silverman's The Organic Chemistry of Drug Design and Drug Action.

Process chemistry is its own world with its own issues. Recommended texts here are Practical Process Research & Development by Neal Anderson and Process Development: Fine Chemicals from Grams to Kilograms by Stan Lee (no, not that Stan Lee) and Graham Robinson.

Case histories of successful past projects are found in Drugs: From Discovery to Approval by Rick Ng and also in Walter Sneader's Drug Discovery: A History.

Another book that focuses on a particular (important) area of drug discovery is Robert Copeland's Evaluation of Enzyme Inhibitors in Drug Discovery.

For chemists who want to brush up on their biology, readers recommend Terrence Kenakin's A Pharmacology Primer, Third Edition: Theory, Application and Methods and Molecular Biology in Medicinal Chemistry by Nogrady and Weaver.

Overall, one of the most highly recommended books across the board comes from the PK end of things: Drug-like Properties: Concepts, Structure Design and Methods: from ADME to Toxicity Optimization by Kerns and Di. For getting up to speed in this area, there's Pharmacokinetics Made Easy by Donald Birkett.

In a related field, the standard desk reference for toxicology seems to be Casarett & Doull's Toxicology: The Basic Science of Poisons. Since all of us make a fair number of poisons (as we eventually discover), it's worth a look.

There's a first set - more recommendations will come in a following post (and feel free to nominate more worthy candidates if you have 'em).

Comments (21) + TrackBacks (0) | Category: Book Recommendations | Drug Development | Life in the Drug Labs | Pharmacokinetics | The Scientific Literature | Toxicology

November 23, 2009

Ozonides As Drugs: What Will They Think of Next?

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Posted by Derek

You know, I often think that I have too narrow a view of what kinds of structures can go into drug molecules. (That may come as worrisome statement for some past and present colleagues of mine, who feel that my tolerances are already set a bit too wide!) But I do have limits; there are some structures that I just wouldn't make on purpose, and which I wouldn't submit for testing even if I made them by accident.

Surely ozonides fall into this category. But when I put the "Things I Won't Work With" stamp on them, at least as far as making them on scale and actually isolating them, some readers pointed out that people were investigating them for antimalarial activity. And here we are, with a new paper in J. Med. Chem. on their activity and properties.

Arterolane is the lead compound, which is in Phase III trials as a combination therapy. And it has to be one of the funkier structures ever to make it as far as Phase III, for sure, with both an ozonide and an adamantane in it. Those two, in fact, sort of cancel each other out - the steric hindrance of the adamantane is surely one of the things that makes the ozonide decide not to explode, as its smaller and more footloose chemical relatives would. You get blood levels of the stuff after oral dosing, a useful (although not especially long) half-life, and no show-stopping toxicity.
arterolane.jpg
Endoperoxides are already known as antimalarials, thanks to the natural product arteminisin, which has led to two synthetic derivatives used as antimalarials. So the step to ozonides was, structurally, a small one, but must have been rather larger psychologically. And that's definitely not something to discount. I probably wouldn't have made compounds of this sort, and it's unnerving (even to me) that arterolane has gone further into the clinic than anything I've ever made. I have to congratulate the people who had the imagination to pursue these things.

Comments (18) + TrackBacks (0) | Category: Drug Development | Infectious Diseases | Odd Elements in Drugs

October 21, 2009

O Brave New World! That Has Such Companies In't!

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Posted by Derek

Steve Usdin at BioCentury sent along a reprint of the newsletter's annual "Back to School" issue from last month (available for open access here) in response to my note about "micropharma" the other day. And it's clear that he's been thinking along the same lines. Whether or not this model is going to work is another question, but that looks like something that we're going to be finding out.

As the issue notes, in a pithy quote from Mike Powell of Sofinnova, the key problem is "how to restructure an industry where it costs $100 million to answer a question but people are only willing to pay you $50 million for the answer." Since the amount of money being handed out is probably not going to increase any time soon, the only way out of that dilemma is to find some way for that first figure to go down.

One of the groups that won't be happy about that process are academic centers that are used to seeing their intellectual property as a potentially lucrative source of funds. The strike-it-rich days do not look to be coming back any time soon. Instead, BioCentury advises universities to get ready to adopt a "non-ROI" approach to developing their ideas, by use of grants, public-private consortia, and help from foundations and other nonprofits. (Perhaps a name like "delayed ROI" or, if you're being especially weasely about it, "enhanced ROI", might help that concept go down a bit smoother).

CRO firms are almost certainly going to have to be part of that process, since there are plenty of skills needed to push a drug target or molecule along that are not found in most universities. That, to me, would indicate a real market for a low-cost CRO outfit targeting academia. I'm not sure if anyone is serving that market, or trying to, but it would seem to have some potential in it. Anyone who can help to run should-we-kill-this experiments, without spending too much money getting the answer, will have something that looks to be in demand.

In general, this landscape would mean that ideas will go longer before companies are formed around them, with the idea that they can be tested out a bit without having to build new corporations to do it. (As another quote from the article had it, "The unmet need in the industry is drugs, not companies".) Payoffs will be slower, and they won't be as large when they come, either. Venture capital investors will be asked to have more patience under this model, and that's not something that they're necessarily noted for. And someone's going to have to have the money (and nerve) to form mid-sized organizations that will pick up the best of the things coming out of academia, since many of them still won't be quite ready to go right into a big organization. The non-humungous companies that have survived to this point might step up and fill this role, and BioCentury also suggests that Japanese and Indian companies might fill this space as well.

The big question is: will people be able to put up with this, or not? After all, no one's envisioning failure rates going down, they're just hoping that the failures will happen sooner and cost less money. Will they? It's not like "fail quickly" hasn't been a goal of companies in the business for years now. But sometimes it's hard to fail any other way than slowly (and expensively).

Well, the common theme to all this (and to most of the other crystal-ball reading going on these days) is that the industry isn't going to be able to go on in the way it's been accustomed to. If you ask a hundred people in this business what it's going to look like ten or fifteen years from now, the only thing you could probably get them to agree on is "Not like it does today". We'll just have to wait to see if they're all playing "Cheat the Prophet" or not. . .

Comments (14) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

September 17, 2009

The Drug Business: A Turbulent Future?

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Posted by Derek

One of this blog's regular correspondents has just been attending a chemistry outsourcing conference (program here), and heard a very interesting talk from Stefan Loren of a Baltimore investment advisory firm, Westwicke Partners. Loren's a product of the Sharpless lab, who went on to Abbott, then Wall Street (Legg Mason and into the hedge fund business), and had some very provocative things to say about our industry:

His talk, "The Pharma Titanic: It's Time to Root for the Iceberg" presented a sobering view of the challenges that big pharma will have to deal with if it wants to survive.

Loren opened with an overview of the US national health care debate. Regardless of the ultimate form that a national system takes, he believes we'll see mandatory insurance; this will be good for big pharma. He also believes that there will be strong pressure for mandatory comparative effectiveness testing...probably not good for big pharma. Who will pay for this and what resources this would require is another matter. Wearing his investment advisor glasses, he sees global pharma sales declining, led by North America, with future growth coming in Asia and Latin America. He also sees evidence of healthcare avoidance in the US: unfilled prescriptions, unfinished courses of prescriptions, and people just not visiting medical and dental practitioners - not a good trend.

The coming wave of patent expirations of the top 10 drugs will hit big pharma hard. Generics will grow: In 5 to 10 years, he predicts that 80 percent of ALL prescriptions will be generic. When coupled with the meager investments in bow wave research over the past 15+ years, as measured by IPOs, there's trouble ahead. Global biotech IPOs are in the toilet and the US is no longer viewed by the investment community as the global leader in biotech. There have been an unprecedented number of bankruptcies in biotech. There is going to be a huge oversupply of production capacity for small molecule manufacturing. ROIs for pharma and biotech are largely negative...it gets worse. He calls this the "death spiral."

Pharma pipelines are seen as very poorly run and wasteful. Poor projects linger far longer than they should. Too much emphasis is placed on me-too and line extensions. Too much emphasis is placed on acquisitions and licensing rather than innovation. Here it comes: he says "I have NEVER seen a merger that worked" We were then entertained by a chart showing Pfizer's stock market performance over the period of time from pre-WLA, through Pharmacia-Upjohn, and now Wyeth...you would not be a happy camper if you had put your retirement account in Pfizer management's hands and their merger mania. Wall Street has a saying "Two dogs don't make a kennel." Of course, what we hear is "this time it's different" along with the usual happy talk about synergies. Loren does believe that mergers can work and can be synergistic if the two companies merging are small...large mergers just don't work and large companies get paralyzed by bureaucratic inertia.

His solution? Break up large pharma into therapeutic areas and build shared networks between distinct entities. Small organizations can operate far more efficiently in decision making about research directions - use the network to maintain manufacturing efficiencies. Small focused companies will revitalize the industry and offer opportunities for scientists coming out of academia. In response to a question from the audience regarding Merck's ambitions to adopt this networked architecture, he doesn't believe they can make it work.

He does see light at the end of the tunnel with respect to supply chain assurance driving a return to sanity. The heparin, glycerin, and melamine disasters have awakened people and the cost of securing global supply chains is going to make US industry much more competitive. It also will focus serious scrutiny on big pharma. The "next heparin" case will have serious personal consequences for big pharma managers. . ."

Well, a good amount of this I agree with, but some of it I'm not sure about. Taking things in order, I don't know about a decline in US sales, but Asia is most definitely where a lot of companies are expecting growth. (And for "Asia", you could substitute "China" and be within margin of error). And his generic prescription figures may not be right on target, but the trend surely is. We've discovered a lot of useful drugs over the years, and anything new we find has to compete against them. The only way to break out of that situation is to find drugs in new categories entirely, and we all know how easy that is.

But as for the US not being the global leader in biotech - well, if we aren't, then who is? You could possibly make a case for "no clear leader at all, for now", but I think that's as far as I can go. And that coming oversupply of manufacturing for small molecule drugs, which may well be real, will be bad news for the companies that have already invested in that area, of course, but good news for up-and-comers, who will be able to pick up capacity more cheaply.

But Loren's comments about mergers I can endorse without reservation. I've been saying nasty things about big pharma mergers since this blog began, and nothing in the last seven years has changed my mind. And I certainly hope that his idea of smaller companies coming along to revitalize the industry is on target, because it's sure not going to be revitalized by (for example) Pfizer buying more people. I've made that Pfizer stock-chart point of his here, as well - like the rest of the industry, PFE stock had a wonderful time of it in the 1990s, but this entire decade it's been an awful place to have your money.

I expect these comments to bring in a lot of comments of their own - so, how much of this future are you buying?

Comments (23) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History | Regulatory Affairs

September 15, 2009

Industrial Research: More Grounded in Reality, or Not?

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Posted by Derek

My post the other day on why-do-it academic research has prompted quite a bit of comment, including this excerpt from an e-mail:

I would also note that mediocrity is hardly limited to academia. I cannot tell you the number of truly dumb things that I continue to see happening in industry, motivated by the need to be doing something - anything - that can be quantified in a report. The idea that industry is where reality takes command is depressingly false, and I would guess that the same thing that distinguishes the best from the rest in academia also applies in the "real world."

Well, my correspondent is unfortunately on target with that one. Industry is supposed to be where reality takes command, but too often it can be where wishful thinking gets funded with investor's cash. I'm coming up on my 20th anniversary of doing industrial drug discovery. I've seen a lot of good ideas and a lot of hard work done to develop them - but I've also seen decisions that were so stupid that they would absolutely frizz your hair. And I'm not talking stupid-in-hindsight, which is a roomy category we all have helped to fill up. No, these were head-in-hands performances while they were going on.

I can't go into great detail on these, as readers will appreciate, but I can extract some recurring themes. From what I've seen the worst decisions tend to come from some of these:

"We can't give up on this project now. Look at all the time and money we've put into it!" This is the sunk-cost fallacy, and it's a powerful temptation. Looking at how hard you've worked on something is, sadly, nearly irrelevant to deciding whether you should go on working on it. The key question is, what's it look like right now, compared to what else you could be doing?

"Look, I know this isn't the best molecule we've ever recommended to the clinic. But it's late in the year, and we need to make our goals." I think that everyone who's been in this business for a few years will recognize this one. It's a confusion of ends. Those numerical targets are set in an attempt to try to keep things moving, and increase the chance of delivering real drugs. That's the goal. But they quickly become ends in themselves, and there's where the trouble starts. People start making the numbers rather than making drugs.

"OK, this series of compounds has its problems. But how can you walk away from single-digit nanomolar activity?" This is another pervasive one. Too many discovery projects see their first job (not unreasonably) as getting a potent compound, and when they find one, it can be hard to get rid of it - even if it has all kinds of other liabilities. It takes a lot of nerve to get up in front of a project review meeting and say "Here's the series that lights up the in vitro assay like nothing else. And we're going to stop working on it, because it's wasting our time".

"Everyone else in the industry is getting on board with this. We've got to act now or be left behind." Sometimes these fears are real, and justified. But it's easy to get spooked in this business. Everyone else can start looking smarter than you are, particularly since you see your own discovery efforts from the inside, and can only see other ones through their presentations and patents. Everyone looks smart and competent after the story has been cleaned up for a paper or a poster. And while you do have to keep checking to make sure that you really are keeping up with the times, odds are that if you're smart enough to realize that you should be doing that, you're in reasonably good shape. The real losers, on the other hand, are convinced that they're doing great.

I'm not sure how many of these problems can be fixed, ours or the ones of academia, because both areas are stocked with humans. But that doesn't mean we can't do better than we're doing, and it certainly doesn't release us from an obligation to try.

Comments (27) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Development | Who Discovers and Why

September 10, 2009

To What End?

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Posted by Derek

I was looking through my RSS feed of journal articles this morning, and came across this new one in J. Med. Chem.. Now, there's nothing particularly unusual about this work. The authors are exploring a particular subtype of serotonin receptor (5-HT6), using some chemotypes that have been looked at in serotinergic ligands before. They switch the indole to an indene, put in a sulfonamide, change the aminoethyl side chain to a guanidine, and. . .wait a minute.

Guanidine? I thought that the whole point of making a 5-HT6 ligand was to get it into the brain, and guanidines don't have the best reputation for allowing you to do that. (They're not the easiest thing in the world to even get decent oral absorption from, either, come to think of it). So I looked through the paper to see if there were any in vivo numbers, and as far as I can see, there aren't.

Now, that's not necessarily the fault of the paper's authors. They're from an academic med-chem lab in Barcelona, and animal dosing (and animal PK measurements) aren't necessarily easy to get unless you have a dedicated team that does such things. But, still. The industrial medicinal chemist in me looks at these structures, finds them unlikely to ever reach their intended site of action, can find no evidence in the paper's references that anyone else has ever gotten such a guanidine hydrazone into the brain, either, and starts to have if-a-tree-falls-in-the-forest thoughts.

Now, it's true that we learn some more about the receptor itself by finding new ligands for it, and such compounds can be used for in vitro experiments. But it's not like there aren't other 5-HT6 antagonists out there, in several different chemical classes, and that's just from the first page of a PubMed search. Many of these compounds do, in fact, penetrate the brain, because they were developed by industrial groups for whom in vitro experiments are most definitely not an end in themselves.

I don't mean to single out the Barcelona group here. Their work isn't bad, and it looks perfectly reasonable to me. It's just that my years in industry have made me always ask what a particular paper tells me that I didn't know, and what use might some day be made of the results. Readers here will know that I have a weakness for out-there ideas and technologies, so it's not like I have to see an immediate practical application for everything. But I would like to see the hope of one. And for this work, and for a lot of medicinal chemistry that comes out of academic labs, I just don't see it.

Update: it's been pointed out in the comments that there's a value in academic work that doesn't have to be addressed in industry, that is, training the students who do it. That's absolutely right. But at the same time, couldn't people be trained just as well by working on systems that are a bit less dead on arrival?

And no, I'm not trying to make that case that academic labs should make drugs. If they want to try, then come on down. If they don't, that's fine, too - there's a lot of important research to be done in the world that has no immediate practical application. But this sort of paper that I've written about today seems to miss both of these boats simultaneously: it isn't likely to produce a drug, and it doesn't seem to be addressing any other pressing needs that I can see, either.

And yes, I could say the same about my own PhD work. "The world doesn't need another synthesis of a macrolide antibiotic", I told people at the time. "But I do". Does it have to be like that?

Comments (28) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development | The Central Nervous System | The Scientific Literature

August 26, 2009

Thalidomide for Myeloma: Whose Idea Was It?

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Posted by Derek

So, if you're a patient with a rare disease (or a relative of a patient with one), and you have an idea for repurposing an old drug for treatment. . .and you get a company interested, and it actually works. . .works to the point that the company takes in a billion or two dollars a year. . .what then?

Some readers will have guessed that I'm talking about thalidomide and Celgene, and right they are. Beth Jacobsen is the person involved - her husband died of multiple myeloma, but her medical sleuthing had turned up the idea of using thalidomide as a therapy for the disease, and she kept up the pressure to have the idea tried out. Celgene's mentioned her in annual reports, and she's been thanked by name in a publication on the clinical results.

But now she's suing Celgene, saying that they misappropriated her idea. Complicating the issue is the question of whether the late Judah Folkman was really the source of the inspiration, in a phone conversation with Jacobsen (earlier versions of the story have it that way, but the lawsuit apparently tells it differently). Which way did it happen? Is Jacobsen indeed owed compensation? And whether she is or not, will she be able to convince a court? Matt Herper has the story at Forbes.

I'll defer my own comments until I know a bit more about the case, but this is definitely an interesting one. I can add something that might be of relevance, though: a search in PubMed for "thalidomide myeloma" turns up 64 pages of references, almost all of them post-1999. But there is this one, from Italy in 1963. Has the idea been around for that long? Someone who can track down that journal can tell us. . .

Comments (20) + TrackBacks (0) | Category: Cancer | Drug Development | Drug Industry History | Patents and IP

August 25, 2009

Polymorphs and Salts: India Raises an Eyebrow

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Posted by Derek

As some of you may know, there's a big patent dispute between Novartis and the government of India. The issue is Gleevec (imatinib, sold as Glivec in most of the rest of the world - Novartis must have figured that it would have been pronounced "Gly-veck" over here). The product is sold as a mesylate salt, and in fact, as a particular polymorph of that mesylate salt, and there's the problem.

For those outside the business, most drugs have either acidic or basic groups on them, and you can make a salt of them by combining them with a corresponding base or acid. Basic drugs - amines, mostly - are often sold as hydrochloride, mesylate, citrate, etc. salts, and acidic drugs are often sodium, potassium, calcium, etc. salts. These changes are usually done to make a compound absorb better when it's dosed and/or to make it easier to handle or more stable during manufacturing and storage.

Polymorphs, meanwhile, are different crystalline forms of the same compound. That's something that you don't encounter much outside a chemistry lab. The closest everyday analog is to think of table salt vs. kosher salt vs. sea salt, but those are still the same crystal-packing form when you get right down to it. A real polymorph is quite a different beast; it's as if you could dissolve up regular salt, cool it down in some tricky way, and have it crystallize out as needles or prisms instead of tiny cubes. And those needles or prisms might then, as it happens, refuse to dissolve if you added them to your soup. That's a polymorph, and it's a pretty common occurrence with drug substances. A key step in a real manufacturing process is making sure that you have the best one, and that you can always be sure that it's the one being produced. The wrong one will do things like refuse to dissolve into the bloodstream, which can be most unfortunate.

So Gleevec is a particular polymorph of a particular salt, and Novartis has patents on just that form in many countries. But not India, or not yet. As this post from a lawyer there details, the dispute is (to a large extent) about whether this form of the drug should be compared to another polymorph, to another salt, or to the original free base compound when time comes to judge its novelty and patentability. Another question is whether Novartis's previous patent filings disclose or anticipate the particular salt and polymorph form of the final compound. These arguments are complicated by the fact that India didn't even allow patents on pharmaceutical substances until a few years ago. For more on recent drug company patent disputes there, see this from the WSJ.

So I'd like to throw a question out to the readership: how many examples can people think of where a particular salt or polymorph was a key to getting good efficacy or properties for a drug? I realize that a lot of these stories never see the light of day - I've seen polymorph problems give people fits during development, as have many readers, I'm sure, but most of these things never get published. So I'm not asking for anything from the inside, just the publicly known examples.

Update: if you want a good indicator of how serious the IP issues are around these things, check out this conference. . .

Comments (35) + TrackBacks (0) | Category: Drug Development | Patents and IP

August 24, 2009

Arzoxifene: Not the Road to Big Profits?

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Posted by Derek

Eli Lilly announced some bad news last week when they dropped arzoxifene, a once-promising osteoporosis treatment (and successor to Evista (raloxifene), which has been one of the company's big successes).

If this drug had been found ten or fifteen years ago, it might have made it though. But the trial data showed that while it made its primary endpoints (reducing vertebral fractures, for example), it missed several secondary ones (such as, well, non-vertebral fractures). And the side effect profile wasn't good, either. That combination meant that the drug was going to face at hard time at the FDA for starters, and even if it somehow got through, it would face a hard time competing with generic Fosamax (and Lilly's own Evista).

So down it went, and it sound like the right decision to make. Unfortunately, given the complexities of estrogen receptor signaling, the clinic is the only place that you can find out about such things. And there are no short, inexpensive clinical trials in osteoporosis, so the company had to run one of the big, expensive ones only to find out that arzoxifene didn't quite measure up. That's why this is a territory for the deep-pocketed, or (at the very least) for those who hope to do a deal with them at the first opportunity.

One more point is worth emphasizing. Take a look at the structures of the two compounds (from those Wikipedia links in the first paragraph). Pretty darn similar, aren't they? Arzoxifene is clearly a follow-up drug in every way - modified a bit here and there, but absolutely in the same family. A "me-too" drug, in other words, an attempt to come up with something that works similarly but sands off some of the rough edges of the previous compound. But anyone who thinks that development of a follow-up compound is easy - and a lot of people outside the industry do - should consider what happened to this one.

Comments (14) + TrackBacks (0) | Category: "Me Too" Drugs | Clinical Trials | Drug Development | Toxicology

August 14, 2009

Spray-Painted For Success

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Posted by Derek

I do a lot of talking around here about how the general public doesn't really have a good idea of what goes on inside a drug company. But a conversation with a colleague has put me to thinking that this might be largely our own fault.

Consider the public face that our industry projects. Look at the press releases and the advertisements - what's the impression that you get? That there is a defined process for discovering drugs, for one thing, and what's more, that we are the master of it. Now, I know that we don't always send out that message. There are attempts to tell people about how many compounds have to be made, how many projects end up failing. But for the most part, we don't press-release that stuff.

No, the press releases are for the investors, and for them, we want to project that we're productive, confident, resourceful. . .in short, that we've got things under control. The last thing Wall Street wants to hear about is that you don't always know which drug targets are the right ones to work on, that you're not quite sure of the best way to prosecute them, and that (despite continuing efforts) these conditions look to obtain for quite a while to come.

And this attitude is one of the things that seeps out into the general public consciousness. That, I think, is why you get people who are convinced that we could cure a lot of these diseases, but that we just don't - you know, for all sorts of evil and profitable reasons. They've bought into our hype. If we haven't cured the common cold, that must be because we make a lot more money selling people stuff for it, not because antiviral drug development is flippin' difficult. (Especially for something like the common cold, but that's another story).

Now, to some extent, there is a defined process for discovering drugs - well, several defined processes. It's just that it doesn't work all that well, not on the absolute scale. No one could look at clinical failure rates of around 90% and say that we've got everything covered. Weirdly, that's one of the things that gives me hope for the industry, that even small improvements would make a big difference. What if only 80% of all the compounds we took into the clinic crashed and burned? That would be great! It would double our success rate!

But when I mention that 90% problem to people outside the drug industry, they usually have no idea. All they hear about are the successes. Perhaps it would do us some good to mention the failures once in a while?

Comments (29) + TrackBacks (0) | Category: Drug Development | Drug Industry History | Why Everyone Loves Us

August 10, 2009

Pharma's Return on Investment: Yikes

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Posted by Derek

There's a recent article in Nature Reviews Drug Discovery that has some alarming figures in it. This is yet another look at the industry from McKinsey, and we'll get to their McKinseyish solutions in a moment. But first, some numbers:

They calculate that the return on investment (ROI) from small-molecule drug research was nearly 12% during the late 1990s, but since 2001 it's been more like 7.5%. If true, that's not a very nice number at all, because their data indicate that most companies assume a capitalization rate of between 8.5 and 11% - in other words, internal industry estimates of what it costs to develop a drug over time now run higher, on average, than the actual returns from developing one.

Another alarming bit of news is their analysis of Phase III failures. From 1990 to 2007 there were 106 of those nasty, expensive events. But the McKinsey figures are that 45% of those failures were due to insufficient efficacy versus placebo - which, in theory, is the sort of thing you're supposed to be rather more sure about by that point, what with having run Phase II trials for efficacy and all. (I'd like to know how many Phase III trials succeeded over that time period as well - what's the overall percentage of failure at that point?) Another 24% of the failures were due to insufficient efficacy versus the standard of care, which is at least a bit more understandable. But together, nearly 70% of all Phase III failures aren't due to tox, they're because the drugs just didn't work as well as their developers thought.

Back to those ROI figures, though. Either those numbers are wrong, or we're in quite a fix. (Of course, since the authors are consultants, their viewpoint is likely that those numbers are the best available, that all of us are indeed in a fix, and that if we pay them money they'll help us out of it). The paper does have some recommendations, to wit:

1. Cut costs, but not the obvious stuff that companies have been doing. Instead, they suggest broader strategies such as considering whether a company's clinical trials are consistently over-powered, and to not do quite as much "planning for success", since most development programs fail. That is, don't automatically gear up for a full overlapping development workup for every compound in the pipeline, but consider staging things so you won't waste as much effort if (or when) they crash out. And naturally, they also suggest outsourcing whatever "non-core" functions there are available.

2. Work faster. I have to say, though, that if I got paid every time I heard this one, I wouldn't have to work. The authors point out, correctly, that delays in getting a compound to market are indeed hideously costly, but on-the-other-hand it by saying that "Of course, gains in speed cannot come from short cuts: the key to capturing value from programme acceleration is choosing the right programmes to accelerate". And that leads into their third category, which is. . .

3. Make better decisions. This isn't quite a much of an eye-roller as it might seem, because this is where they bring in those Phase III numbers above. Such failures suggest some deeper problems:

"In our experience, many organizations still advance compounds for the wrong reasons: because of momentum, 'numbers-focused' incentive systems or through waiting too long to have tough conversations about the required level of product differentiation."

And I have to say, they have a point. People who've been in the industry for some years will have seen all of those mistakes made. for sure. But figuring how to stop those things from happening is the tough part, and presumably that's one of the things that McKinsey is selling.

Comments (45) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

July 17, 2009

Drug Approvals, Natural And Unnatural

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Posted by Derek

I seem to have been putting a lot of graphics up this week, so here's another one. This is borrowed from a recent Science paper on the future of natural-products based drug discovery. It's interesting both from that viewpoint, and because of the general approval numbers:
Nat%20Prod%20drugs%20and%20approvals%20graph.jpg
And there you have it. Outside of anomalies like 2005, we can say, I think, that the 1980s were a comparative Golden Age of Drug Approvals, that the 1990s held their own but did not reach the earlier heights, and that since 2000 the trend has been dire. If you want some numbers to confirm your intuitions, you can just refer back to this.

As far as natural products go, from what I can see, the percentage of drugs derived from them has remained roughly constant: about half. Looking at the current clinical trial environment, though, the authors see this as likely to decline, and wonder if this is justified or not. They blame two broad factors, one of them being the prevailing drug discovery culture:

The double-digit yearly sales growth that drug companies typically enjoyed until about 10 years ago has led to unrealistically high expectations by their shareholders and great pressure to produce "blockbuster drugs" with more than $1 billion in annual sales (3). In the blockbuster model, a few drugs make the bulk of the profit. For example, eight products accounted for 58% of Pfizer’s annual worldwide sales of $44 billion in 2007.

As an aside, I understand the problems with swinging for the fences all the time, but I don't see the Pfizer situation above as anything anomalous. That's a power-law distribution, and sales figures are exactly where you'd expect to see such a thing. A large drug company with its revenues evenly divided out among a group of compounds would be the exception, wouldn't it?

The other factor that they say has been holding things back is the difficulty of screening and working with many natural products, especially now that we've found many of the obvious candidates. A lot of hits from cultures and extracts are due to compounds that you already know about. The authors suggest that new screening approaches could get around this problem, as well as extending the hunt to organisms that don't respond well to traditional culture techniques.

None of these sound like they're going to fix things in the near term, but I don't think that the industry as a whole has any near-term fixes. But since the same techniques used to isolate and work with tricky natural product structures will be able to help out in other areas, too, I wish the people working on them luck.

Comments (10) + TrackBacks (0) | Category: Business and Markets | Drug Assays | Drug Development | Drug Industry History

July 8, 2009

How Much Does the Drug Industry Spend on Marketing?

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Posted by Derek

Anyone who defends the pharmaceutical industry has to be ready to hear, over and over and over, about how much it spends on sales and marketing versus R&D. This is thought to be a telling point about where the priorities really are. I've addressed this one several times, and my best response is to point out that sales and marketing are actually supposed to bring in more money than you spend on them, and do so more reliably than R&D in the short term.

There's now a very useful paper in Nature Reviews Drug Discovery looking at just this issue. The authors (from three universities in the US and Israel) are looking into the general question of which is the better use of money: put it into R&D for the long term, or promote existing products for the short term? I should make clear at the outset that those two options do line up in that way. R&D expenditures take years to pay off, if ever, given the amount of time that drug development takes. And marketing of a current product had better start paying off in a shorter time frame, because every patented drug is a wasting asset, constantly being eaten into by competition and by its time to patent expiration.

So which makes more financial sense? The authors numbers from the Wharton databases on publicly traded drug companies, looking at those with more than $50 million in sales. Using the company stock prices as a measure of value (J. Finance LVI(6), 2431–2456 (2001), I'm giving you references here), they found, in general, that R&D investments have a net positive effect, while increased promotion has a negative effect. (See also Rev. Account Stud. 7, 355–382 (2002), another journal I don't reference much). Both effects are larger for smaller companies, as you might expect, but they held up across the industry. The effect also holds up if you factor out the compensation packages of the top five executives of each company (which is a nice control to run, I have to say). And yes, since you ask, there is a negative effect on stock price that correlates to higher executive compensation, and I'm willing to bet that this effect holds for more than just the drug industry.

Since we're talking about stock prices, which are generally forward-looking, the way to interpret these results is probably that investors expect R&D expenditures to pay off in the long term, but actually expect sales and marketing expenditures to reduce long-term value. If that's so, then why spend money on marketing? The reason the authors propose is just what I'd been talking about: short-term reliability. Drug discovery and development is inherently risky, and promotion of existing products is (at least comparatively) more of a sure thing. Companies engage in a mix of the two to try to even the cash flow out. (And as the authors note, if executive compensation is tied more to short-term performance, then there's an incentive to go with the short-term gains).
NRDD%20graph.jpg
In general, though, you'd figure that companies should invest more in R&D. And here's the real kicker: that's exactly what's been happening. As this graph from the paper shows, over the last thirty years expenditures in the Sales, General, and Administrative area have risen only slightly as a per cent of sales. The Cost of Goods Sold category (materials, physical plant, manufacturing facilities, etc.) has gone proportionally down, with an interesting excursion in the mid-1990s. (Note also that this used to be the leading category). And R&D expenditures (again, as a per cent of sales) rose in the 1980s, were flat in the 1990s, and have risen since then. Overall, since 1975, the proportion of money spent on R&D has more than tripled, from 5% to 17%.

This, I hardly need point out, does not fit the narrative of some of the e-mails and comments I get. Some perceptions of the drug industry have us, Back In the Old Days, as spending our money on R&D, only to slimily slide into becoming pure marketing businesses as time has passed, with our recent years being especially disgusting and rapacious. According to these figures, this is at the very least not accurate, and comes close to being the opposite of the truth. Comments are welcome - most welcome, indeed.

Comments (58) + TrackBacks (0) | Category: Business and Markets | Drug Development | Drug Industry History

June 29, 2009

Eli Lilly Gives It Away

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Posted by Derek

Not long ago, I wrote about a Pfizer program for smaller companies to come screen their targets against Pfizer's compound bank. Now Eli Lilly has flipped that around. In an initiative to bring other people's compounds out of the stockrooms and off the shelves, they'll screen them for free.

These aren't single-target assays. The company has four phenotypic screens going (for Alzheimer's, diabetes, cancer, and osteoporosis) and will look for improvement by any mechanism that comes to hand. No chemical structure information is shown to Lilly (I assume that they just know the molecular weight so they can run a dilution series). If something looks interesting, the company and the owners of the chemical matter have 120 days to come to terms for any further development deal - if not, then all rights revert to the submitter, and they can publish the data from the screens.

Lilly's working out a universal material transfer agreement, in collaboration with a number of universities, so that the paperwork stays the same every time. That's a good move. The lawyering can be a real holdup - in my experience, every party in these agreements usually comes in with slightly different wording in their magic legal spells, requiring several rounds of reconciliation before everyone's ready to sign.

I think that this is a worthwhile idea, and that they'll get a lot of takers. There are plenty of compounds sitting around in academic labs gathering dust, so why not send 'em in? The worst that can happen is nothing, and the best is that the compound actually turns out to be worth something. But will anything come out of it? The closest program to this is surely the National Cancer Institute's long-standing (since 1990) NCI-60 screening program, which also runs at no cost to the submitters. Even so, a recent reference mentions that there are between 40,000 and 50,000 compound in the NCI database, which actually seems rather small, considering. (To be fair, the program is not being funded at the levels that it was during the early 1990s). The only marketed compound that I'm aware of that can be said to have come out of the NCI-60 screen is Velcade (bortezomib), known then as PS-341, which was sent in for screening by Proscript Pharmaceuticals in the mid-1990s. Many other interesting structures have turned up along the way, though, which for various reasons haven't made it all the way through.

It'll be quite interesting to see what sort of hit rate Lilly's phenotypic assays call up - I hope they tell us. I have a lot of sympathy for the mechanism-agnostic approach myself, and I'd like to see how closely my bias are aligned to reality.

Comments (18) + TrackBacks (0) | Category: Drug Assays | Drug Development

June 23, 2009

Medarex, Ipilimumab, Prostate Cancer, And Reality

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Posted by Derek

What's really going on with Medarex and ipilimumab? The company made news over the weekend with a press release from the Mayo Clinic, detailed what appears to be a substantial response in two prostate cancer patients. But the more you look at the story, the harder it is to figure out anything useful.

As this WebMD piece makes clear, this study is not a trial of ipilimumab as a single agent. The patients are undergoing prolonged androgen ablation, the testosterone-suppressing therapy that's been around for many years and is one of the standard options for prostate cancer. The trial is to see if ipilimumab has any benefit when it's added to this protocol - basically, to see if it can advance the standard of care a bit.

WebMD quotes Derek Raghavan at the Cleveland Clinic as saying that androgen ablation can sometimes have dramatic results in patients with locally advanced prostate cancer, so it's impossible to say if ipilimumab is helping or not. That's why we run clinical trials, you know, to see if there's a real effect across a meaningful number of patients. But (as this AP story notes) we don't know how many patients are in this particular study, what its endpoints are, or really anything about its design. All we know is that two patients opted out of it for surgery instead. (Credit goes to the AP's Linda Johnson for laying all this out).

Ipilimumab is an antibody against CTLA-4, which is an inhibitory regulator of lymphocytes. Blocking it should, in theory, turn these cells loose to engage tumor cells more robustly. (It also turns them loose to engage normal tissue more robustly, too - most of the side effects seem to be autoimmune responses like colitis, which can be very severe. The antibody has been studied most thoroughly in melanoma, where it does seem to be of value, although the side effect profile is certainly complicating things.

So overall, I think it's way too early to conclude that Medarex has hit on some miracle prostate cure. This press release, in fact, hasn't been too helpful at all, and the Mayo people really should know better.

Comments (34) + TrackBacks (0) | Category: Clinical Trials | Drug Development | Press Coverage | Toxicology

One. . .Billion. . .Dollars!

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Posted by Derek

The In Vivo Blog has a piece that everyone who follows small-company press releases should read. "When Is a Billion Dollars Not a Billion Dollars?", they ask. And the answer is, of course, when someone's press-releasing it. Read the whole thing, but here's the short form: when someone says "We just signed a deal worth a billion dollars!", too often they're leaving out the rest of the sentence. It's supposed to continue like this: ". . .if every single thing goes perfectly and all our drugs work and become the biggest successes they possibly can." And since that happens, like, all the flippin' time, well. . .

Comments (5) + TrackBacks (0) | Category: Business and Markets | Drug Development

June 22, 2009

Funky Carbocycles

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Posted by Derek

Earlier this month I posted about rolofylline, which I noted has a rather unusual noradamantane attached to it. Now check out this ORL-1 compound from Banyu, complete with the not-so-widely-heard-of bicycloheptane-spirocyclopropane group.

This was not arrived at lightly, as you'd imagine. There's a table in the Supporting information for the paper, but I'll quote from the body of the main manuscript:

Various kinds of cycloalkanes, substituted or nonsubstituted cyclopropyl rings to medium sized rings (such as cyclopentylmethyl, cyclohexylmethyl, cycloheptylmethyl, cyclooctylmethyl, cyclononylmethyl, cyclodecylmethyl), spiroalkane (such as spiro[2.5]octanemethyl, spiro[3.5]nonanemethyl, spiro[4.5]decanemethyl, spiro[2.4]heptanemethyl, spiro[3.4]octanemethyl, spiro[4.4]nonanemethyl), bicycloheptane (such as methylbicyclo[2.2.1]heptylmethyl, dimethylbicyclo[2.2.1]heptylmethyl, spirocyclopropanebicycloheptanemethyl), and branched alkanes (such as 3,3-dimethylbutane, 3,3-dithylbutane, 1-methylcyclobutaneethyl, 1-methylcyclopentaneethyl, 1-methylcyclohexaneethyl) were tested.

No, that couldn't have been a lot of fun. Anyone else out there found themselves having to optimize grease recently?

Comments (5) + TrackBacks (0) | Category: Drug Development | Life in the Drug Labs

Genzyme's Virus Problems

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Posted by Derek

We organic chemists have it easy compared to the cell culture people. After all, our reactions aren't alive. If we cool them down, they slow down, and if we heat them up, they'll often pick up where they left off. They don't grow, they don't get infected, and they don't have to be fed.

Cells, though, are a major pain. You can't turn your back on 'em. Part of the problem is that there are, as yet, no cells that have evolved to grow in a dish or a culture bottle. Everything we do to them is artificial, and a lot of it what we ask cultured cells to do is clearly not playing to their strengths. Ask Genzyme: they use the workhorse CHO (Chinese Hamster Ovary) cells to produce their biologics, but they've been having variable yield problems over the past few months. Now it turns out that their production facilities are infected with Vesivirus 2117 - I'd never heard of that one, but it interferes with CHO growth, and that's bringing Genzyme's workflow to a halt. (No one's ever reported human infection with that one, just to make that clear).

I assume that the next step is a complete, painstaking cleanup and decontamination. That's going to affect supplies of Cerezyme (imiglucarase) and Frabazyme (agalsidase) late in the summer and into the fall, although it's not clear yet how long the outage will be. Any cell culture lab that's had to toss things due to mycoplasms or other nasties will sympathize, and shudder at the thought of cleaning things up on this scale.

Comments (21) + TrackBacks (0) | Category: Biological News | Drug Development

June 19, 2009

More Hot Air From Me on Screening

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Posted by Derek

After yesterday's post on pathway patents, I figured that I should talk about high-throughput screening in academia. I realize that there are some serious endeavors going on, some of them staffed by ex-industry people. So I don't mean to come across as thinking that academic screening is useless, because it certainly isn't.

What is probably is useless for is enabling a hugely broad patent application like the one Ariad licensed. But the problem with screening for such cases isn't that the effort would come from academic researchers, because industry couldn't do it, either: Merck, Pfizer, GSK and Novartis working together probably couldn't have sufficiently enabled that Ariad patent; it's a monster.

It's true that the compound collections available to all but the very largest academic efforts don't compare in size to what's out there in the drug companies. My point yesterday was that since we can screen those big collections and still come up empty against unusual new targets (again and again), that smaller compound sets are probably at even more of a disadvantage. Chemical space is very, very large. The total number of tractable compounds ever made (so far) is still not a sufficiently large screening collection for some targets. That's been an unpleasant lesson to learn, but I think that it's the truth.

That said, I'm going to start sounding like the pointy-haired boss from Dilbert and say "Screen smarter, not harder". I think that fragment-based approaches are one example of this. Much smaller collections can yield real starting points if you look at the hits in terms of ligand efficiency and let them lead you into new chemical spaces. I think that this is a better use of time, in many cases, than the diversity-oriented synthesis approach, which (as I understand it) tries to fill in those new spaces first and screen second. I don't mind some of the DOS work, because some of it's interesting chemistry, and hey, new molecules are new molecules. But we could all make new molecules for the rest of our lives and still not color in much of the map. Screening collections should be made interesting and diverse, but you have to do a cost/benefit analysis of your approach to that.

I'm more than willing to be proven wrong about this, but I keep thinking that brute force is not going to be the answer to getting hits against the kinds of targets that we're having to think about these days - enzyme classes that haven't yielded anything yet, protein-protein interactions, protein-nucleic acid interactions, and other squirrely stuff. If the modelers can help with these things, then great (although as I understand it, they generally can have a rough time with the DNA and RNA targets). If the solution is to work up from fragments, cranking out the X-ray and NMR structural data as the molecules get larger, then that's fine, too. And if it means that chemists just need to turn around and generate fast targeted libraries around the few real hits that emerge, a more selective use of brute force, then I have no problem with that, either. We're going to need all the help we can get.

Comments (25) + TrackBacks (0) | Category: Academia (vs. Industry) | Drug Assays | Drug Development

June 17, 2009

The View From Pfizer's Corner Offices

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Posted by Derek

There's a good article from Lee Howard up at The Day (the New London/Groton newspaper) on the changes going on at Pfizer. It's the story according to management, though, which is worth having for its compare-and-contrast uses:

Despite the looming uncertainty, according to company spokesmen, the new research structure has added energy and urgency to the drug-discovery process in Groton. . .

. . .The changes in Groton - seen most plainly in displays of logos the new business units are in the process of choosing - have added drug-development staff and even legal experts to the R&D mix, along with biologists and chemists who typically have worked in close proximity. In the middle of it all sits the chief scientific officer of each business unit, as well as other managers.

The idea is to develop a more realistic idea of a drug's likelihood to succeed at an early stage and then bring it to market quicker if it seems to be working.

I hope that the process of choosing new logos doesn't take too long. You could get a reasonable read on the success of any attempt to remake Pfizer's culture by counting the number of meetings the logo process has required so far.

But I can't make fun of the goals that the company is setting - they're perfectly sensible. The only problem is that they're just what everyone else is trying to do, too, and if it were easy, everyone would be finished doing them by now. The problem with trying to get an earlier decision of a drug's chances for success are that many of the serious problems don't show up (in fact, can't show up) until larger clinical trials. And I don't think that anyone's got a good way around that one yet. Some therapeutic areas are better suited than others, to be sure.

Would the new structures that Pfizer's putting in place have prevented the torcetrapib disaster? I doubt it - that one took everyone by surprise. Would they have prevented the Exubera disaster? Now, that one's food for thought, because it seemed to be much more self-inflicted. If the company can avoid doing that sort of thing again, then they've accomplished something.

And for all the nasty things I say about Pfizer here, I hope that they do accomplish things. After all, they're the biggest drug company in the world, and they seem determined to stay that way. If an organization that huge ends up spinning its wheels (or sitting around designing new business cards), it can't be good for anyone.

Comments (37) + TrackBacks (0) | Category: Drug Development | Drug Industry History

June 15, 2009

Ugliness Defined

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Posted by Derek

Yesterday's post on so-called "ugly" molecules seems to have touched a few nerves. Perhaps I should explain my terms, since ugliness is surely in the eye of the beholder. I'm not talking about particular functional groups as much as I'm talking about the whole package.

First off, a molecule that does what it's supposed to do in vivo is (by my definition) not truly ugly. The whole point of our job as medicinal chemists is to make active compounds - preferably with only the activity that we want - and if that's been accomplished there can be no arguing. Of course, "accomplished" has different meanings at different stages of development. Very roughly, the mileposts (for those of us in discovery research) are:

1. Hitting the target in vitro.
2. Showing selectivity in vitro.
3. Showing blood levels in vivo.
4. Showing activity in vivo.
5. No tox liabilities in vivo.

And these all have their gradations. My point is that if you've made it through these, at least to a reasonable extent, your molecule has already distinguished itself from the herd. The problem is that a lot of structures will fly through the first couple of levels (the in vitro ones), but have properties that will make it much harder for them to get the rest of the way. High molecular weight, notable lack of polarity (high logP), and notable lack of solubility are three of the most important warning signs, and those are what (to me) make an ugly molecule, not some particular functional group.

My belief is that, other things being equal, you should guard against making things that have trouble in these areas. You may well find yourself being forced (by the trends of your project) into one or more of them; that happens all the time, unfortunately. But you shouldn't go there if you don't have to. It's also true that there are molecules that have made it all the way through, that are out there on the market and still have these liabilities. But that shouldn't be taken as a sign that you should go the same route.

Ars longa, vita brevis. There's only so much time and so much money for a given project, and your time is best spent working in the space that has the best chance of delivering a drug. A 650 molecular weight compound with five trifluoromethyl groups is not inhabiting that space. It's not impossible that such a compound will make it, but I think we can all agree that its chances are lower compared to something smaller and less greasy. If the only thing you can get to work is a whopper like that, well, good luck to all concerned. But we have to depend on luck too much already in this business, and there's no reason to bring in more.

Comments (13) + TrackBacks (0) | Category: Drug Development | Life in the Drug Labs | Pharmacokinetics

June 2, 2009

A Deuterium Deal

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Posted by Derek

Well, there's someone who certainly believes in the deuterated-drug idea! GlaxoSmithKline has announced today that they've signed a deal with Concert Pharmaceuticals to develop these. There's a $35 million payment upfront, which I'm sure will be welcome in this climate, and various milestone and royalty arrangements from there on out. I know that the press story says that it's a "potential billion dollar deal", but you have to make a useless number of assumptions to arrive at that figure. Let's just say that the amount will be somewhere between that billion-dollar figure and. . .well, the $35 million that Glaxo's just put up.

Where things will eventually land inside that rather wide range is impossible to say. No one's taken such a compound all the way through development, and every one of them is going to be different. (Deuterium might be a good idea, but it ain't magic.) It looks like the first compound up for evaluation will be an HIV protease inhibitor, CTP-518, which is a deuterated version of someone's existing compound - Concert has filed paten applications on deuterated versions of both darunavir (WO2009055006) and atazanavir (WO2008156632). The hope is that CTP-518 will have an improved enough metabolic profile to eliminate the need to add ritonavir into the drug cocktail.

The company is also providing deuterated versions of three of GSK's own pipeline compounds for evaluation, which is interesting, since that's the sort of thing that Glaxo could do itself. In fact, that's one of the key points to the whole deuterated-compound idea: the window of opportunity. Deuteration isn't difficult chemistry, and the applications for it in improving PK and tox profiles are pretty obvious (see below). It's a good bet that drug company patent applications will hencrforth include claims (and exemplified compounds) to make sure that deuterated versions of drug candidates can't be poached away by someone else. This strategy has a limited shelf life, but it's long enough to be potentially very profitable indeed.

One more note about that word "obvious". Now that people are raising all kinds of money and interest with the idea, sure, it looks obvious. And I'm sure that it's a thought that many people have had before - and then said "Nah, that's too funny-sounding. Might not work. And besides, you might not be able to patent it. And besides, if it were that good an idea, someone else would have already done it. There must be a good reason why no one's done it, you know". Getting up the nerve to try these things, that's the hard part. Roger Tung and Concert (and the other players in this field) deserve congratulations for not being afraid of the obvious.

Comments (25) + TrackBacks (0) | Category: Business and Markets | Drug Development | Infectious Diseases | Pharmacokinetics | Who Discovers and Why

June 1, 2009

Akt and Mek, But Not PDQ

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Posted by Derek

Well, the ASCO meeting has been roaring along, with dozens of press releases coming out. (Go to Google News and type that acronym in if you want to get the full experience). They range from the pretty-interesting to the despair-inducing, but one bit of news struck me as particularly worth noting. That's the early-stage deal between Merck and AstraZeneca to combine two of their development candidates in a Phase I trial.

That's Merck's AKT inhibitor MK-2206 and AZ's Mek inhibitor AZD6244, and there's room to think that combining those two mechanisms could be beneficial. But as that In Vivo Blog link details, this deal wasn't initiated through any official contact between the two companies. Rather, someone from Merck and someone from AZ got to talking while they were going through airport security in Dublin, and recognized each other's names. A mere year and a half later, the deal was born.

There's a lot to learn from that story. For one, big drug companies are not, for the most part, looking to do early-stage deals with other big drug companies. Perhaps we'll see more of these in the future, but in general, it's about the least likely form of partnership. Another thing to note is how long it took for this idea to bear fruit. Eighteen months is about right for companies of this size to make up their minds about something like this - and you can decide that (since the oncology field is so complicated) that this is a reasonable period of evaluation, or you can decide, equally objectively, that delays of that magnitude remind you of a sauropod turning around in puzzlement three hours after something bit its tail.

I'm impressed that the deal was made at all. The usual path for new ideas of this sort is to the graveyard, especially in very large organizations, so I have to assume that some people within each company must have really pushed things along to make it happen. It's part of the general bias toward inaction: it's harder to get beaten up for decisions that you didn't make, compared to decisions that you did. Missed opportunities are often invisible.

So, no matter how long it took, or even whether it works out, I still have to congratulate the people involved on getting this agreement to happen. It's worthwhile, I think, just because it's the sort of thing that doesn't happen very often. And I have the feeling that (in the coming years) we're going to have to explore a lot of things in this industry that haven't happened very often. We'll need the practice!

Comments (4) + TrackBacks (0) | Category: Business and Markets | Cancer | Clinical Trials | Drug Development | Drug Industry History

May 28, 2009

Deuterated Drugs: The PTO Says OK, So Far

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Posted by Derek

As a follow-up to the deuterated-drugs idea, I note (courtesy of a co-worker) that Concert Pharmaceuticals has press-released their first issued patents on deuterated analogs of existing drugs.

So apparently the novelty and utility requirements have passed the first major sniff tests. I don't know if the case to be made for these (rimonabant and mosapride) is different than the others that Concert has on their IP assembly line, but I doubt it. If these issued, you'd figure that the others probably will, too. I can't imagine that the rimonabant patent's going to be worth all that much, though, since that drug has failed for reasons that I can't see being addressed by a deuterium analog.

As mentioned here before, though, the IP space here seems to be rather crowded, at least when you look at the number of applications. It's presumably quite a traffic jam at the patent offices - and it'll presumably be some time before that gets sorted out. And that's just at this stage of the game: if any of the companies in this space start to hit it big, it wouldn't surprise me to see lawsuits, requests for re-examination and the like.

Comments (14) + TrackBacks (0) | Category: Drug Development | Patents and IP

May 21, 2009

The NIH Takes the Plunge

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Posted by Derek

The NIH has announced that they're going to start up a preclinical drug discovery effort to address rare diseases. I find this interesting for several reasons. For one thing, it's worth a try for conditions where no company has seen a way to fund research, and there are quite a few of them. Treating rare diseases can be quite profitable in the industrialized world (ask Genzyme, among other companies), but if the conditions are localized in poorer areas no one's likely to take a crack at them. So my first reaction is "Good, and the best of luck to you". The NIH has been getting closer to doing preclinical drug discovery in recent years, so this is a logical next step.

The second thought I have is that this will be an interesting experience for the researchers involved. There's nothing quite like drug discovery, and if they do it right, everyone will come away with an appreciation of just how complicated a process it is. The only way to make it simple and reasonable is to cut corners. I notice that the press release says:

Typically, drug development begins when academic researchers studying the underlying cause of a disease discover a new molecular target or a chemical that may have a therapeutic effect. Too often, the process gets stuck at the point of discovery because few academic researchers can conduct all the types of studies needed to develop a new drug. If a pharmaceutical company with the resources to further the research does get involved, substantial preclinical work begins with efforts to optimize the chemistry of the potential drug. This involves an iterative series of chemical modifications and tests in progressively more complex systems — from cell cultures to animal tests — to refine the potential medicine for use in people. Only if these stages are successful can a potential treatment move to clinical trials in patients.

Unfortunately, the success rate in this preclinical process is low, with 80 to 90 percent of projects failing in the preclinical phase and never making it to clinical trials. And the costs are high: it takes two to four years of work and $10 million, on average, to move a potential medicine though this preclinical process. Drug developers colloquially call this the "Valley of Death."

. . .If a compound does survive this preclinical stage, TRND will work to find a company willing to test the therapy in patients. There are several stages to the clinical trials process that can take several years before the safety and efficacy of a new drug is determined. FDA will only approve a drug for general use after it passes these trials. The clinical trials process is also expensive, but the failure rate is lower at this stage.

Well, a tiny bit lower. I think that the general clinic-to-market failure rate is still somewhere around 90%, but it varies by therapeutic area. And that 80 to 90% failure rate that they quote for preclinical is a bit lowballed, I'd say, because you'd want to subtract that things that get recommended to the clinic (but really should never have been). But overall, this is a reasonably clear-eyed look at the difficulties involved. If they can get some things to the point that a company or foundation is willing to take on the (now somewhat reduced) risks, that'll be great.

The last thought I have (for now) is that I feel like writing a bunch of people and asking them why the NIH is doing this, since they've been telling me for years that this is what the NIH already does, anyway. The "Big Pharma does nothing but rip off NIH" meme hasn't surfaced for a little while, but it's always out there.

Comments (15) + TrackBacks (0) | Category: Drug Development | Drug Industry History

May 14, 2009

Goldman Sachs: Out Of the Drug Funding Business Already?

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Posted by Derek

Late last year, I wrote about a possible new way to fund drug discovery, a private-equity model that seemed to be in the works at Goldman Sachs. The driving force behind the idea seemed to be Jon Symonds, former CFO at AstraZeneca.

Well, as the InVivoBlog noted yesterday, Symonds has suddenly decamped to Novartis. He’s press-released as their new CFO (after the current one retires), which makes you wonder what’s happened to that drug funding plan. Given the current environment for new financing schemes, and for banking in general (not to mention the current environment at Goldman Sachs), has the whole idea just been shelved?

As the In Vivo folks go on to say, financing clinical candidates in this way isn’t necessarily a bad idea – it just might be a bad time to try it out. There are a lot of issues to be worked out, but it’s looking more and more like no one’s going to be working them out any time soon. . .

Comments (2) + TrackBacks (0) | Category: Business and Markets | Clinical Trials | Drug Development

May 5, 2009

Farewell to ACAT, and to Lots of Time and Money, Too

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Posted by Derek

Back when I joined the first drug company I ever worked for, the group in the lab next door was working on an enzyme called ACAT, acyl CoA:cholesterol acyltranferase. It’s the main producer of cholesterol esters in cells, and is especially known to be active in the production of foam cells in atherosclerosis. It had already been a drug target for some years before I first heard about it, and has remained one.

It hasn’t been an easy ride. Since 1990, several compounds have failed in the clinic or in preclinical tox testing. The most recent disappointment was in 2006, when pactimibe (Daiichi Sankyo) not only failed to perform against placebo, but actually made things slightly worse.

Lipid handling is a tough field, because every animal does is slightly differently. There are all sorts of rabbit strains and hamster models and transgenic mice, but you're never really sure until you get to humans. Complicating the story has been the discovery that there are two ACATs. ACAT-1 is found in macrophages (and the foam cells that they turn into) and many other tissues, and ACAT-2 is found in the intestine and in the liver. Which one to inhibit is a good question - the first might have a direct effect on altherosclerotic plaque formation, while the second could affect general circulating lipid levels. Pactimibe hits both about equally, as it turns out.

Now a second study of that drug has been published this spring. This one was going on at the same time as the earlier reported one, and was stopped when those results hit, but the data were in good enough shape to be worked up, and the company paid for the continued analysis. The new results look at patients with familial hypercholesterolemia, who got pactimibe along with the standard therapies. Unfortunately, the numbers are of a piece with the earlier ones: the drug did not help, and actually seemed to increase arterial wall thickness. I think it's safe to say, barring some big pharmacological revelation, that ACAT inhibitors are a dead end for atherosclerosis.

I bring this up for two reasons. One is that the group that was working next door to me on ACAT was the same group that discovered (quite by accident) the cholesterol absorption inhibitor ezetimibe, known as Zetia (and as half of Vytorin). Although its future is very much in doubt, it's for sure that that compound has been a lot more successful than any ACAT inhibitor. The arguing goes on about how helpful it's been (and will go on until we see the next trial results for another couple of years), but it's already made it further than ACAT.

And that's actually my second point. I suspect that almost no one in the general public has ever heard of ACAT at all. But it's been the subject of a huge amount of research, of time and work and money. And while we've learned more about lipid handling in humans, which is always valuable, the whole effort has been an utter loss as far as any financial return. I have no good way of estimating the direct costs (and even worse, the opportunity costs) involved with this target, but they surely add up to One Hell Of A Lot Of Money. Which is gone, and gone with hardly a sound outside the world of drug development. And this happens all the time.

Comments (15) + TrackBacks (0) | Category: Cardiovascular Disease | Clinical Trials | Drug Development | Drug Industry History | Toxicology

April 13, 2009

An HIV Drug. Or A Gout Drug? Or Both. . .

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Posted by Derek

We get a lot of surprises in this business, most of them not so good. That's understandable, since there are lot more ways for drugs and their mechanisms to go wrong than there are for them to go right. But once in a while, you do see something that's unexpectedly good news.

That may be what's happened to a small San Diego outfit, Ardea. As Xconomy details, the company (formed out of the remnants of IntraBiotics and Valeant) was testing an HIV compound in the clinic when they noticed significant declines in blood levels of uric acid.

That rang a bell: something that decreases uric acid levels would be useful for gout, and there's only been one new gout drug approved in the last 40 years. Follow-up work showed that the effect seemed to be coming from a metabolite of the original drug, and thanks to the HIV trial data, they already had good hopes for that compound's safety. The new compound, RDEA594, has made it through Phase I and is headed for Phase II, and the trials look to be manageable affairs that the company can afford to run. The market is there: more people have gout in the US than are HIV-positive (although the two diseases clearly aren't comparable in other respects!). But the state of HIV research now means, weirdly, that the serious medical needs in that population are actually being met more completely than those in many other disease areas. (Ardea's HIV compound is progressing as well).

So good luck to them, on both fronts. It's a reminder to always look through all your data, and to be alert for whatever opportunities might be hiding in there. We don't get as many as we'd like, so we can't let any of them slip away.

Comments (11) + TrackBacks (0) | Category: Drug Development | Infectious Diseases

April 3, 2009

The Mechanical Chemist?

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Posted by Derek

We use a lot of automated equipment in the drug discovery business. There’s an awful lot of grunt work involved, and in many cases a robot arm is better suited to the task – transferring solutions, especially repetitive transfers of large numbers of samples, is the classic example. High-throughput screening would just not be possible if you had to do it all by hand; my fingers hurt just imagining all the pipetting that would involve.

But I wouldn’t say that the process of medicinal chemistry is at all automated. That’s very much human-driven, and a lot of the compounds on most med-chem projects are made by hand, one at a time. Sure, there are parallel synthesis techniques, plates and resins and multichannel liquid handlers that will let you set up a whole array of reactions at once. But you do that, typically, only after you’ve found a hot compound, and that’s often done the old-fashioned way. (And, of course, there are a lot of reactions that just don’t lend themselves to efficient parallel synthesis).

But I remember the first time I saw an automated synthetic apparatus, back at an ACS meeting in the mid-1980s. There was a video in the presentation (a real rarity back then), and it showed this Zymark arm being run to set up an array of reactions, assay each of them after an overnight run, and report on the one that performed the best. “Holy cow”, I thought, “someone’s invented the mechanical grad student”. Being a grad student at the time, I wasn’t so sure what I thought about that.

This all comes to mind after reading a report over at Wired about a robotic system that has been claimed to have made a discovery without much human input at all. “Adam”, built at Aberystwyth University in Wales, seems to have been set up to look for similarities in yeast genes whose function hadn’t yet been assigned, and then (using a database of possible techniques) set up experiments to test the hypotheses thus generated. The system was also equipped to be able to follow up on its results, and eventually uncovered a new three-gene pathway, which findings were confirmed by hand.

And Ross King, leading the project at Aberystwyth, is apparently extending the idea to drug discovery. Using a system that (inevitably) will be called “Eve”, he plans to:

. . .autonomously design and screen drugs against malaria and schistosomiasis.

"Most drug discovery is already automated," says King, "but there's no intelligence — just brute force." King says Eve will use artificial intelligence to select which compounds to run, rather than just following a list.

Well, I won't take the intelligence comment personally; I know what the guy is trying to say. I’ll be very interested to see how this is going to be implemented, and how it will work out. (I'll get an e-mail off to Prof. King asking for some details). My first thought was that Eve will be slightly ahead of a couple of the less competent people I’ve seen over the course of my career. And if I can say that with a straight face (and now that I think about it, I believe that I can), then there may well be a place for this sort of thing. I’ve long held that jobs which can be done by machines really should be done by machines.

But how is this going to work? The first way I can see running a computational algorithm to design drugs would be some sort of QSAR, and we were just talking about that here the other day – most unfavorably. I can imagine, though, coding in a lot of received wisdom of drug discovery into an expert system – Topliss tree for aryl substituents, switch thiophene for phenyl, move nitrogens around the rings, add a para-fluoro, check both enantiomers, put in a morpholine for solubility, mess with the basicity of your amine nitrogens, no napthyls if you can help it, watch your logD - my med-chem readers will know just the sorts of things I mean.

Now, automating that, along with feedback from the primary and secondary assays, solubility, PK, metabolite ID and so on. . .mix it in with literature-searching capability for similar compounds, some sort of reaction feasibility scoring function, ability to order reagents from the stockroom, analyze the LC/MS and NMR traces versus predictions, weight the next round of analogs according to what the major unmet project goals are. . .well, we're getting to the mechanical medicinal chemist, sure enough. Now, not all of these things are doable right now. In fact. some of them are rather a long way off. But some of them could be done now, and the others, well, they're certainly not impossible.

I'm not planning on being replace any time soon. But the folks cranking out the parallel libraries, the methyl-ethyl-butyl-futile stuff, they might need to look over their shoulders a bit sooner. That's outsourcing if you like - from the US to China and India, and from there to the robots. . .

Comments (28) + TrackBacks (0) | Category: Drug Development | Drug Industry History | General Scientific News | Life in the Drug Labs

March 25, 2009

Two! Two! Two Drugs in One!

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Posted by Derek

There's an idea that shows up in the antibiotic field that seems a bit crazy by the standards of other therapeutic areas. Since bacteria develop resistance to single agents, why not take two different classes of antibiotic molecule and, y'know, string 'em together somehow? How about that, eh?

Well, it's the sort of thought that occurs either to people who don't know much about drug discovery, or to those who know an awful lot. In between, you're probably going to dismiss that one as something of an eye-roller. But while it's got some problems, it's not quite as much of a bozo move as it appears. Here's an example that just showed up in J. Med. Chem., where a group tied Cipro (ciprofloxacin) to neomycin.

The first objection is "Why don't you just give people two pills, instead of trying to make them all into one molecule?" (Here's a review that talks about both options). Well, one answer is that two different agents are going to have different absorption and PK, whereas a conjugate drug will be coming on all at the same time, which could be an advantage. But a more compelling answer is that the new conjugate is going to be a different creature at both of its drug targets, and might well be different enough at both to qualify as a new agent to the resistant strains.

The molecules described in that paper above are, depending on your point of view, fluoroquinolones with a lot of sugars hanging off of them - most unusual as far as traditional quinolone SAR - or neomycin oligosaccharides with some odd heterocycles hanging off of them in turn, which is also not the sort of thing that's usually tried on that scaffold. So if you can still hit both targets, you may well be able to hit them with something they haven't seen before (and may not yet know how to deal with). Importantly, in the case of those quinolone/neomycin thingies, some evidence is shown in the paper that bacteria have a harder time developing resistance to the new compounds. (In order to completely evade them, the bacteria will have to mutate out of both targets, too, but that advantage mostly holds with two separate pills as well).

But all this brings up the second objection: how do you think you're going to get away with hanging all that stuff off an active compound? Well, that's why this trick is usually done with known antibiotics. The SAR of these things has been well worked out by now, and that includes the parts of the molecule that don't seem to have much effect on things. Those will be the preferred positions to attach your linking groups, they're the nonessential region(s) of the molecule that can be messed with.

There's a potential show-stopper in all this, though, and it can be seen on display in the J. Med. Chem. paper. Sticking two drug molecules together, no matter how you do it, is going to make a rather large entity. Neomycin, for its part, didn't start out very small, and the linkers used in this paper aren't the tiniest things on the shelf, either (although I do like the use of the triazole click reaction, mentioned yesterday as well). It turns out that the resulting double-barreled compounds are better than plain neomycin, but worse than plain Cipro. And this happens in spite of the fact that when you assay them against the fluorquinolone target enzymes (DNA gyrase and topoisomerase IV), the new compounds are actually more potent than the original drug. So what's the problem?

Well, the problem, almost certainly, is that these things are probably just too huge. The disconnect between enzyme and bacterial potency here may well reflect trouble getting into the bacteria (although that doesn't seem to be hurting the neomycin end of the activity so much). Larger molecules are trouble when dosed orally, too, and I'd expect compounds like the ones shown to be difficult to develop as traditional pills. (That said, there's a real need for IV-based antibiotics for nasty hospital-derived infections, so something like this could still fly, as long as it showed activity against real bacteria).

So this idea is hard to realize, but it's not necessarily crazy. It keeps showing up in the antibiotic world, and here's an account of the same concept being applied to malaria therapy. Eventually someone's going to get this to work.

Comments (19) + TrackBacks (0) | Category: Drug Development | Infectious Diseases

March 4, 2009

Gene Expression: You Haven't Been Thinking Big Enough?

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Posted by Derek

Well, here’s another crack at open-source science. Stephen Friend, the previous head of Rosetta (before and after being bought by Merck), is heading out on his own to form a venture in Seattle called Sage. The idea is to bring together genomic studies from all sorts of laboratories into a common format and database, with the expectation that interesting results will emerge that couldn’t be found from just one lab’s data.

I’ll be interested to see if this does yield something worthwhile – in fact, I’ll be interested to see if it gets off the ground at all. As I’ve discussed before, the analogy with open-source software doesn’t hold up so well with most scientific research these days, since the entry barriers (facilities, equipment, and money) are significantly higher than they are in coding. Look at genomics – the cost of sequencing has been dropping, for sure, but it’s still very expensive to get into the game. That lowered cost is measured per base sequenced – today’s technology means that you sequence more bases, which means that the absolute cost hasn’t come down as much as you might think. I’m sure you can get ten-year-old equipment cheap, but it won’t let you do the kind of experiments you might want to do, at least not in the time you’ll be expected to do them in.

But even past that issue, once you get down to the many labs that can do high-level genomics (or to the even larger number that can do less extensive sequencing), the problems will be many. Sage is also going to look at gene expression levels, something that's easier to do (although we're still not in weekend-garage territory yet). Some people would say that it's a bit too easy to do: there are a lot of different techniques in this field, not all of which always yield comparable data, to put it mildly. There have been several attempts to standardize things, along with calls for more control experiments, but getting all these numbers together into a useful form will still not be trivial.

Then you've got the really hard issues: intellectual property, for one. If you do discover something by comparing all these tissues from different disease states, who gets to profit from it? Someone will want to, that's for sure, and if Sage itself isn't getting a cut, how will they keep their operation going? Once past that question (which is a whopper), and past all the operational questions, there's an even bigger one: is this approach going to tell us anything we can use at all?

At first thought, you'd figure that it has to. Gene sequences and gene expression are indeed linked to disease states, and if we're ever going to have a complete understanding of human biology, we're going to have to know how. But. . .we're an awful long way from that. Look at the money that's been poured into biomarker development by the drug industry. A reasonable amount of that has gone into gene expression studies, trying to find clear signs and correlations with disease, and it's been rough sledding.

So you can look at this two ways: you can say fine, that means that the correlations may well be there, but they're going to be hard to find, so we're going to have to pool as much data as possible to do it. Thus Sage, and good luck to them. Or the systems may be so complex that useful correlations may not even be apparent at all, at least at our current level of understanding. I'm not sure which camp I fall into, but we'll have to keep making the effort in order to find out who's right.

Comments (16) + TrackBacks (0) | Category: Biological News | Drug Development

February 27, 2009

Your Paper Is A Sack Of Raving Nonsense. Thank You.

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Posted by Derek

You don’t often get to see the sort of fistfight that’s detailed in the latest issue of Organic Process Research and Development. Patents whose procedures are hard to reproduce are familiar to every industrial chemist, unfortunately, but coming across one that seems completely mistaken in its most important details is rare. And this is the first time I’ve seen one of these dragged out into the open literature for a give-and-take with the original authors about whether they’re delusional or not. (The editors of the journal seem to be in new territory themselves on this one).

I should add here that the great majority of patent preps I’ve followed have worked pretty much as described, and I don’t think that my success rate in reproducing them is any worse than procedures from the chemical journals. Some journals more than others, of course, (another topic!) but OPRD is known to be very, very reproducible indeed. As it should be: it’s a journal for process chemists, whose livelihood is refining chemical routes until they’re scalable, economical, and (very importantly) until they work exactly the same way every time they’re run.

So here’s the situation. In 2007, the journal published a paper by a group from Dr. Reddy’s Laboratories, a large Indian company that does both generic drugs and has their own drug discovery operation. (There are, I should note, some academic co-authors who seem to have completely disappeared during this current food fight). The paper covered a synthesis of S-citalopram, and it caught the attention of the process chemists at Lundbeck, in Denmark. And well it might – citalopram (Celexa and other brand names), an antidepressant, was discovered there in the late 1980s, and has been generic since 2003.

The original paper (Eliati et al.) described a new alkylation reaction route to produce a key intermediate and a resolution of it (and of citalopram) into pure enantiomers by forming chiral salts. So far, so good – these sorts of things are the heart of process chemistry, and entirely appropriate for a paper in OPRD. But only if they work.

The Lundbeck group (Dancer and de Diego), had tried that exact resolution of citalopram many times themselves, though, without success, so they were rather taken aback to see it published as working just fine. They detail their attempts to reproduce the Eliati procedure, and demonstrate in great detail that it indeed does not work as written. I won’t go into their experimental work, which is very extensive and painstaking, but nothing the Lundbeck team could do resulted in anything better than a 55:45 mixture, which is a rather poor substitute for a pure compound. Midway through their paper, they start putting the word “resolution” in quotation marks when discussing the Eliati procedure, and the arm’s-length-and-holding-the-nose attitude is very successfully conveyed. The phrases “enormous disparity”, “effectively impossible”, “extremely unlikely”, and “not feasible in any meaningful, practical sense” all make appearances.

They also were surprised at the alkylation reaction reported in the Eliati paper, which is the only one of its kind reported in the literature – well, other than a patent by the same team from Dr. Reddy’s, that is. The weird thing about it is that it uses 3-chloropropylamine, apparently as the isolated free base. My chemistry audience will now be raising their eyebrows, because this is not a compound that you’d expect to be very happy as anything but a salt. It should, in fact, start reacting with itself quite vigorously, with plenty of HCl being given off in the process. But the Eliati procedure doesn’t have enough base to allow for anything else, and they use (supposedly) 12 grams of the stuff in 2.5 mL of DMSO. Since no paper or patent has ever reported isolation of this free base, it’s a rather odd compound to drop into your manuscript without explanation.

Another example of the same reaction in the Eliati paper is even weirder. Not only do they use this never-before-seen chloropropylamine, but this time they do the reaction in acetone, at 60 to 65 degrees C, by first adding 7.5 grams of potassium t-butoxide to 40 mL of the acetone. Now that prep should get the attention of the organic chemists in the audience, because that sounds like an excellent way to make a bunch of hot polymerized gunk. For one thing, acetone boils at 56, so how you get it to 65 is a real stumper. And adding a strong base to it is a surefire way to deprotonate it and start the famous aldol condensation (and every other base-catalyzed ketone reaction you can think of, for that matter). The Lundbeck group tried it, out of sheer curiosity, and got:

”. . . a vigorous/violent reaction. . .with the formation of a quantity of a white solid. (It had) an odor of higher ketones/alkenes, and analysis by NMR indicated that it was a complex mixture of products, with peaks consistent with condensation products of acetone.

A solid majority of the chemists reading that sentence, you can bet, finished reading that and added a “No shit” to the end. This is the sort of thing a sophomore undergraduate should be able to spot, and my guess is that whoever reviewed the Eliati paper for OPRD has had some interesting correspondence with the journal. The resolution is one thing – that’s impossible to spot if you haven’t worked with that exact reaction. But this alkylation step is ridiculous.

The journal gave Eliati and co-workers a chance to respond to all this, and followed that with a last word from Dancer and de Diego at Lundbeck. These things are all published back to back; it's like watching a boxing match. The Dr. Reddy’s group runs up the white flag immediately on the chiral salt resolution, actually, agreeing that their published procedure doesn’t work. But they claim that a modified version of the procedure does work, and that they “inadvertently missed incorporating a few words in the text” of the article which would have made this clear. The Lundbeck group isn’t buying this for a minute. They point out that the manuscript would have been had to have been substantially reworked to make it into this different procedure, for one thing. And even worse, the details of it as reported by Eliati are internally inconsistent, with the masses and ratios not even adding up. And finally, they report their own attempts to reproduce the new procedure, and find that it, too, is basically impossible.

And as for the alkylation, Eliati et al. claim that if you work quickly, you can use the chloropropylamine free base as they described. They also present a table showing how long it lasts under different conditions and in different solvents, and claim to have done the best variation of the reaction on a six-kilo scale. The acetone reaction, they admit, wasn’t as clean, but they didn’t spend much time talking about that because their “aim was to isolate the desired product instead of the aldol product.” Dancer and de Diego aren’t very happy with that either, continuing to insist that the acetone procedure is “completely unworkable”. As for the chloropropylamine, they welcome the clarifications in the second Eliati paper, but point out that said details contradict themselves at one point, and at any rate, none of them are to be found in the corresponding Dr. Reddy’s patent application, which continues to talk about using only the free base, and (on top of everything else) in a way that makes no sense.

The final Lundbeck reply has a telling line in the acknowledgements, which is, in its way, even more pointed than anything else in their paper: “One of us (R.J.D.) thanks Sir John Cornforth for inspiration derived from a series of his articles in a similar case some years ago.” That’s the famous “Some Comments on a Paper by Samir Chatterjee” affair, Tetrahedron Letters 1980 709 and 1982, 2213. Cornforth completely demolished some heterocyclic chemistry work by the unfortunate Chatterjee, pointing out by several lines of evidence that the whole thing had to have been faked. Name-dropping this example is about as direct a statement of your opinion as the scientific literature will allow. . .