There's a constant running battle in the drug industry between the two kinds of pharmaceutical companies: the ones who discover the drugs first, and the ones who sell the drugs cheaply after the patents have expired. It surprises me still how many people I run into (outside my work) who don't make that distinction, or who don't even realize that there is one.
But the generic industry is a very different place. Their research budgets are far smaller than the ones at the discovery companies, since they're only dealing with drugs that everyone knows to already work. Their own research is directed toward satisfying the regulatory requirements that they're making the equivalent substance, and to finding ways to make it as cheaply as possible. And some of them are very good at it - some ingenious syntheses of marketed drugs have come out of the better generic shops. Of course, some real head-shaking hack work has, too, but that you can find everywhere.
The tension between the two types of company is particularly acute when a big-selling drug is nearing its patent expiration. It's very much in the interest of the generic companies to hurry that process along, so often they challenge the existing patents on whatever grounds they can come up with, figuring that the chances of success jutify the legal expenses. Since the 1984 Hatch-Waxman act, there's been an even greater incentive, the so-called "Paragraph IV" challenge. A recent piece in Science now makes the case that this process has gotten out of control.
After four years of a drug's patent life, a generic company can file an Abbreviated New Drug Application (ANDA) and challenge existing patents on the grounds that they're either invalid or that the ANDA doesn't infringe them. (This, for example, is what happened when Teva broke into Merck's Fosamax patent, taking the drug generic about four years early). If the challenge is successful, which can take two or three years to be resolved, the generic company gets an extra bonus of 180 days of exclusivity. The authors of the Science piece say that this process is tipped too far toward the generic side, and it's cutting too deeply into the research-based companies. (As noted here, that's rather ironic, considering the current debate about such provisions for biologic drugs, where some parties have been citing the Hatch-Waxman regime as a wonderful success story in small molecules).
This all took a while to get rolling, but the big successes (such as the Fosamax example) have bred plenty of new activity. There are now five times as many Paragraph IV challenges as there were at the beginning of the decade. Teva, for example, which is one of the big hitters in the generic world, had 160 pending ANDAs in 2007, of which 92 were running under Paragraph IV. Here's a look at some recent litigation in the area, which has certainly enriched various attorneys, no matter what else it's done.
Under Hatch-Waxman, a new drug starts off with five years of "data exclusivity" during which a generic version can't be marketed. The Science authors argue that the losses from Paragraph IV now well outweigh the gains from this provision, and that the term should be extended (which would put it closer to those found in Europe, Canada, and Japan. They also bring up the possibility of selectively extending data exclusivity case-by-case or for certain therapeutic areas, but I have to say, this makes me nervous. There are too many opportunities for gamesmanship in that sort of system, and I think that one goal of a regulatory regime should be to make it resistant to that sort of thing.
But I do support the article's main point, which is that the whole generic industry depends on someone doing to the work to discover new drugs in the first place, and we want to make sure that this engine continues to run. Politically, though, anything like this will be a very hard sell, since it'll be easy to paint it as a Cynical Giveaway to the Rapacious and Hugely Profitable Drug Companies. But speaking as someone working for the RHPDCs, I can tell you that we are indeed having a tougher time coming up with the new products with which to exploit the helpless masses. . .