I’ve previously written about how U.S. Patent No. 8,889,135 (the ‘135 patent) covering Abbvie’s blockbuster rheumatoid arthritis drug, Humira® (adalimumab), was invalidated by the U.S. Patent Trial and Appeal Board’s (the “PTAB”) in three separate Inter Partes Review (“IPR”) proceedings, two of which were filed by Boehringer Ingelheim (IPR2016-00408 and IPR2016-00409). While Boehringer Ingelheim filed two challenges to the same ‘135 patent, Coherus filed six challenges to a different Humira patent, U.S. Patent 9,085,619 (“the ‘619 patent”). Such aggressive use of PTAB proceedings is not uncommon, and today I want to look at the strategy behind filing multiple PTAB challenges to the same patent and the reasoning behind such sequential or parallel challenges.
The ‘619 Humira patent at issue in this case is directed to the drug’s formulation. Only claims 16–19 and 24–30 are challenged, with independent claim 16 reciting:
16. An aqueous pharmaceutical formulation comprising:
(a) an anti-tumor necrosis factor alpha antibody comprising a light chain variable region (LCVR) having a CDR3 domain comprising the amino acid sequence of SEQ ID NO:3, a CDR2 domain comprising the amino acid sequence of SEQ ID NO:5, and a CDR1 domain comprising the amino acid sequence of SEQ ID NO: 7, and a heavy chain variable region (HCVR) having a CDR3 domain comprising the amino acid sequence of SEQ ID NO:4, a CDR2 domain comprising the amino acid sequence of SEQ ID NO: 6, and a CDR1 domain comprising the amino acid sequence of SEQ ID NO:8, wherein the concentration of the antibody is 50 to 200 mg/ml; and (b) water;
wherein the formulation does not comprise a buffering system.
Formulation patents are important for any company seeking to manufacture a biosimilar of Humira.
Four of the Coherus IPR petitions were filed on January 31, 2017, as follows:
Several weeks later, on March 2, 2017, Coherus filed two additional IPR petitions:
5. IPR2017-01008 asserted obviousness in view of the 2003 Humira® Label, Fransson, and Gorkan ‘011, and obviousness over Gorkarn ‘011 in view of the 2003 Humira® Label.
6. IPR2017-01009 asserted obviousness in view of the 2003 Humira® Label, Fransson, and the 2005 Gamimune ® Label.
On April 11, 2017, the PTAB granted Coherus’s unopposed motions to dismiss IPR2017-00826 and IPR2017-00827 (IPRs 3 and 4, above) without prejudice. Coherus essentially replaced IPR2017-00826 and IPR2017-00827 with IPR2017-01008 and IPR2017-01009 (IPRs 5 and 6, above). Thus, Coherus has four IPR petitions pending and is awaiting institution decisions against the ‘619 patent.
There are several reasons for companies to file sequential IPR proceedings such as Coherus did against the ‘619 patent.
First, there are technical advantages to be gained by filing multiple IPRs against a single patent. Each IPR petition is limited to a specific word count. In the case of filing any petition before the PTAB, the limit is 14,000 words. If the petitioner is looking to challenge multiple claims and using multiple prior art references, or if the patent contains numerous claims, then this word limit could be problematic. To avoid exceeding the word limit, the petitioner could separate out his arguments over more than one IPR.
Second, and more importantly, filing more than one IPRs against a single patent gives the petitioner multiple “bites at the apple.” Each IPR is a pretty good lottery ticket in the post-grant patent invalidation game in the US. A look at recent IPR data shows that, when a case reaches a final written decision, the odds of invalidating all challenged patent claims is around 67%. In fact, the patent holder is only successful less than 20% of the time. https://www.wsgr.com/publications/PDFSearch/PTAB-Year-in-Review-2016.pdf) Thus, while filing one IPR is favorable, filing more than one can increase the odds of success. Big companies launching critical product lines find these odds appealing and often “double down” on the IPR process in an attempt to reduce the risk of failure.
Third, filing multiple IPRs allows you to challenge a patent using different prior art or different combinations of prior art. This, of course, requires the petitioner to carefully evaluate the arrows in their quiver and to strategically decide which prior art arrows to launch in an IPR attack and which, if any, to reserve for potential future battles, such as another IPR proceeding or even in a litigation. Such decisions are important in light of a company’s overall IP strategy. If a company challenges a patent in an IPR proceeding using prior art reference X, and the IPR is unsuccessful, then the company can try to challenge the patent in a subsequent IPR proceeding using reference Y. If the company is successful with only reference X, then there is no need to disclose reference Y and the company can hold on to reference Y until a litigation, if any, is initiated. If the company, however, tries to challenge a patent using all of its references immediately, and is unsuccessful, then the company may not have any further means of challenging the patent. The failure of the IPR in this scenario leaves the patent in an extremely strong and enforceable position, and the challenger with no defenses. In this case, the company may not be able to enter the market until the patent expires or unless the patent holder is amenable to granting a license.
Fourth, timing must also be strategically considered since challenging a patent multiple times can help a challenger learn from their mistakes in earlier proceedings. This is what happened when Kyle Bass and the Coalition for Affordable Drugs filed two separate petitions against the Ampyra® patents, namely U.S. Patent Nos. 8,663,685, 8,007,826, 8,440,703, and 8,354,437, which constitute four of the five Ampyra® Orange-book listed patents. Kyle Bass’s first IPR petition against the Ampyra® patents was denied because he did not establish that the cited posters displayed at conferences qualified as prior art “printed publications” as required by 35 U.S.C. § 311(b). In the second challenge, however, there was a question regarding the “printed publication” status of Acorda’s S-1 Statement, but the PTAB found a “sufficient showing that the S-1 was publicly accessible to the public interested in the art.”
Fifth, filing multiple IPRs could be used as a means of intimidation. Faced with multiple instituted IPR challenges, a patent holder may simply fold and give up if the patents are not critical to their business. Alternatively, multiple IPR challenges can motivate a patent holder to license the technology if previously they were unwilling to license. In this way, filing multiple IPR challenges creates a bargaining chip that is sort-of a “win-win” for the challenger if they are successful. However, it should be noted that settlements between the parties do not necessarily mean the IPR will be terminated (though in practice they usually are terminated) as it is ultimately up to the PTAB to decide whether termination is merited.
Finally, a biosimilar company such as Coherus may take an aggressive approach to PTAB proceedings to challenge patents as a way to eliminate at least some patent disputes without participating in the patent dance, which is part of the Biologics Price Competition and Innovation Act (BPCIA). By eliminating patents in front of the PTAB, a biosimilar applicant can avoid the cost and uncertainty of litigating patents in court.
Multiple IPR filings against a single patent offer several benefits to the challenges and show that even patent owners who successfully avoid one IPR challenge may still face a subsequent IPR challenges by the same party.
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