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DBL%20Hendrix%20small.png College chemistry, 1983

Derek Lowe The 2002 Model

Dbl%20new%20portrait%20B%26W.png After 10 years of blogging. . .

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: Twitter: Dereklowe

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November 28, 2011

Amgen's New Patent: Explanations, Anyone?

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Posted by Derek

Perhaps someone with a better knowledge of the biomolecule patent world can answer this one for me: just how did Amgen suddenly carve out a whole new patent lifetime for Enbrel? This is US patent 8,063,182, and it's hard for me to unravel what the new parts are or how and why this got issued. Merck and others who have been eyeing biosimilars in this area have no doubt already formulated their legal challenges to it. But what's that line of attack going to be?

Update: explanation in the comments. This application was filed in 1995 and had a long, long history at the patent office before finally being granted. Now, of course, the thing runs for 17 years from date of issue. The law has since been changed to keep this exact sort of thing from happening, with a term of 20 years from the application date. But Amgen applied under the old rules, and gets to live by them. I'm still wondering what the difference is between this patent and the others on Enbrel, though. . .

Comments (21) + TrackBacks (0) | Category: Patents and IP


1. CCguy on November 28, 2011 2:02 PM writes...

In the NYTimes story they have the details:

"The application for the new patent was filed in 1995. But it took until Tuesday to get through the Patent Office because it was reworked and at one point rejected, forcing Amgen to appeal.

Patents now run 20 years from the date of application, to avoid situations like this where an invention gets extended protection because of delays or maneuvers at the patent office. But since this patent was filed before the law changed, it is governed by the old rules and lasts for 17 years from the date of issuance.

Amgen benefited from a similar situation with its anemia drug Epogen, which is still protected by patents even though it has been on the market since 1989."

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2. Biotechtranslated on November 28, 2011 3:30 PM writes...

The incredible thing is, the analysts at Sanford C. Bernstein estimate that this patent adds $6/share in value to Amgen's stock (if the patent holds).

Considering the stock is floating around $55/share, a 9%+ bump in value (another $4B or so) is pretty dam good for a single patent office decision.


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3. alig on November 28, 2011 3:49 PM writes...

September 12, 1989 was the priority date for the application in Switzerland. May 19, 1995 was the US filing.

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4. CCguy on November 28, 2011 4:06 PM writes...

I'm no expert on biomolecule IP, but comparing the 2 patents' claim sections, the original (expiring 2012) claims the DNA (plus expression vectors and host cells) encoding Enbrel, while the new one claims the protein itself.

Original patent:

New patent:

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5. will on November 28, 2011 5:37 PM writes...

Definitely no expert on biotechnology, but it seems to me if there was previously a patent on the DNA used to make the protein (and that DNA could not be used to make any other type of protein), then a claim on the protein itself should be considered an obvious variation on the DNA claim, in which case, the term of the new patent should not be allowed to be extended past the expiration of the first (this is called obvious-type double patenting)

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6. a-non on November 28, 2011 5:42 PM writes...

As indicated by Derek, this patent is a quirk of the US patent law system. For any patent the key date for assessing whether it is novel and non-obvious is the priority date. On a quick check, both this patent and the previous Amgen patent share the same priority date. Therefore, in this case, the earliest priority date is way back in 1989, but because the patent term is calculated from the date of acceptance by the patent office, it has 17 years to run. Now the law has been amended the patent term runs for 20 years and begins a maxiumum of 12 months after the earliest priority date (which I hasten to add is the situation in the rest of the world)

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7. pete on November 28, 2011 5:49 PM writes...

Stunning that Amgen could pull this off. Big bonus to the lawyers - again.

And big bonuses to come as lawyers flock to the patent challenges that'll undoubtedly pile at the doors of the legal process.

That should add a few cents to the drug costs for you and me.

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8. PharmaHeretic on November 28, 2011 9:06 PM writes...

Any comments??

Big drugmakers are submitting to investors’ short-sightedness instead of doing the right thing.

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9. patentgeek on November 28, 2011 9:32 PM writes...

The view of a chemist who also loves patent law:

US 5,610,279 (expiring Oct. 2012) claims certain DNA sequences encoding polypeptides related to the TNF-a receptor, expression vectors containing them, and cells transformed or transfected by those vectors.

US 8,063,182, the recent issue, claims fusion proteins comprising fragments of soluble TNF-a receptor plus certain domains of human IgG heavy chains.

These are fundamentally different inventions, by different groups of inventors. I don't make any comment on whether the '182 patent should have issued in light of the prior art; I have not done such analysis. But the fact that both patents have claims that read on Enbrel does not in and of itself say anything about the patentability of the '182 claims over those of the '279 patent. It is perfectly common for a single commercial product to be within the scope of multiple patents claiming distinct (though possibly related) inventions.

Nothing in the '279 patent teaches the fusion proteins of the '182 patent.

Double patenting considerations (statutory or non-statutory) are not relevant; the two patents do not share a common inventor and are not commonly owned. (See MPEP 804.)

Nor do the '182 and '279 patents share a priority date. The earliest filing to which the '279 patent claims priority is 1989; the earliest filing to which the '182 patent claims priority is Sept. 1990. The continuity chain of the '279 patent has several CIPs, and I don't know if the issued claims are supported by the earliest filing date. But, all of the filing dates (continuations of all types) of the two continuity chains are different from each other.

The New York Times article refers to "situations like this where an invention gets extended protection because of delays or maneuvers at the patent office". One of Amgen's "maneuvers" was to appeal a final rejection of their claims, a process which is lengthy through no fault of the applicant. Some might call this arguing for your rights to the full extent allowed in a society of laws. A view on whether or not Amgen behaved properly is something properly formed after a careful study of the prosecution record of the patent in question. Did any of the commentators in the press do such analysis? It may well be that such an analysis will be wielded successfully by a litigator challenging the patent; but I don't think it's appropriate to assume bad acting absent an analysis of the facts. And note the dishonesty of "where an invention gets extended protection"; as is clear, the two inventions are distinct. It is the commercial product that got extended protection.

As always, things are more complex when you look at the actual facts of a situation. This is never truer than in patent law.

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10. Patent Chemist on November 28, 2011 9:35 PM writes...

It looks like in this case there was a restriction requirment in the earlier patent - where the examiner said there were too many inventions to examine. So Amgen were forced to file the second application as a "divisional application." If the second application claimed what Amgen were forced to cancel from the earlier application as a result of a restriction requirement, then the "double patenting" referred to in an earlier comment would not be an issue.

Interestingly Amgen still has a further application pending (08/444,791 filed on 05-19-1995) which claims priority back to this application's parent application, so potentially Amgen may get yet a further extension.

The cut-off for filing applications so as to still get the 17 year from issue term was June 8, 1995: it is probably not a coincidence that these applications were filed just before that date!

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11. Patent Chemist on November 28, 2011 9:57 PM writes...

Patentgeek appears not to be right that the applications are not related. US 8,063,182 is a division of US 5,610,279. The patents have common ownership and inventorship and claim priority back to the same CH application.

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12. patentgeek on November 28, 2011 9:58 PM writes...

@ Patent Chemist:

I think we're all discussing multiple patents! The news stories on the '182 patent refer to the expiration of "the Enbrel patent" as October 2012, which corresponds to the '279 patent (reissued as RE 36,755), listed on the PTO site and Orange Book for Enbrel. So I referred to this one in my comments, as did a couple of other Pipeliners.

But you're right, the '182 was a DIV, and there's an earlier patent issued from the parent; and of course, the '182 is immune to ODP rejections over the earlier patent as a DIV. So it's maybe not clear which earlier patent people are getting het up over.

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13. patentgeek on November 28, 2011 10:07 PM writes...

@ Patent Chemist:

Sorry! My bad! I meant US 5,712,155, reissued as RE 36,755 (Craig A. Smith et al.) . '279 is the first issue from the parent that also gave rise to '182, as you correctly note.

Totally my fault for the confusion.

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14. patentgeek on November 28, 2011 10:15 PM writes...

Dear all:

In my posts of 9:32 PM and 9:58 PM, references to US 5,610,279 (the '279 patent) should be replaced by US 5,712,155 (the '155 patent, reissued as RE 36,755).

Thanks to Patent Chemist for correcting this egregious switcheroo. I am in shame.

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15. Patent Chemist on November 29, 2011 12:29 AM writes...

So I wonder what the relationship - if any - between the '279 patent family (patents assigned on their face to Roche) and the '155 patent. They seem to have started out from different companies and ended up protecting the same product.

Also interesting is that the recent patent appears to have an earlier effective filing date than the patent that is just about to expire.

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16. patentgeek on November 29, 2011 7:37 AM writes...

I believe that Immunex, who owned the '155 patent, licensed the application that matured into the '279 and '182 patents from Roche in 1999. Immunex was subsequently acquired by Amgen in 2002, who thereby acquired the ownership to the '155 patent, and the exclusive license from Roche for the Roche application.

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17. petros on November 29, 2011 8:21 AM writes...

There is a fair bit of complex crosslicensing of the technology in biotech patents, as well as much litigation.

As other posters have noted this patent, as with those on Epogen, has benefited from the quirks of the US patent system.

But, unless overturned, it will severely hinder attempts to introduce any biosimilars of Enbrel in the US.

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18. David Borhani on November 29, 2011 12:23 PM writes...

@9 (patentgeek)

I don't believe that these are "fundamentally different inventions". The '155 claims are to DNA sequences "which encodes a polypeptide that is capable of binding to TNF" (and similar wording). The '182 claims are to "A protein comprising (a) a human tumor necrosis factor (TNF)-binding soluble fragment" (and similar wording). Both subject matter *proteins*, in the end, bind TNF. And both (obviously, from Amgen's point of view) cover Enbrel in a composition-of-matter sense.

The (sad?) reality is that this fiasco (IMHO) is entirely due to a quirk of the changing patent laws, which Amgen is using to full advantage.

It will be interesting to see who wins in court.

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19. Anonymous BMS Researcher on November 29, 2011 11:08 PM writes...

This sort of thing is why lawyers get paid more than scientists like me.

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20. Susan on December 1, 2011 4:08 AM writes...

In conclusion, what I understand is that there is no double patenting between the '155 and '182 patents, nor between the '279 and '182 patents and therefore, the expiration date of '182 patent would be 22/11/28. Am I right?

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21. Frustrated Momma on June 19, 2013 7:59 PM writes...

Bottom line, our daughter's enbrel is $2,300/month and our individual "grandfathered" health plan has a $5000 pharmacy cap that will not change. Her enbrel has increased in price $700/month since 2011. Whatever games were played are sick. Hopefully Merck will develop a generic that can be ordered from Canada.

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