Sandoz lost two IPRs challenging Humira® patents - what does this mean for other biosimilars?

Zachary Silbersher

Sandoz was denied institution on two IPRs against Humira® patents owned by AbbVie.  As we previously discussed, in late 2017, Sandoz filed eight different IPRs against Humira® patents.  Two of those IPRs just failed to reach institution.  What are the take-aways, for Sandoz and any other Humira® biosimilars?

Sandoz has attacked seven patents covering different indications for Humira® and one patent covering a formulation (U.S. Patent 8,802,100).  On February 9, the PTAB denied institution of an IPR challenging a patent for treating plaque psoriasis with the Humira® antibody (U.S. Patent No. 9,512,216) as well as Sandoz’s IPR against the ‘100 patent. 

The PTAB rejected the IPR against the ‘216 patent because Sandoz relied upon the Humira® package insert to teach certain dosage limitations of the patent.  The PTAB, however, found that Sandoz failed to show that the Humira® package insert from 2002 constituted a “printed publication,” which it must in order to act as prior art.  Because of that finding, the PTAB summarily dismissed the IPR without substantively analyzing Sandoz’s arguments.

Technically, this deficiency is fixable, and Sandoz could collect more evidence showing that the package insert was, in fact, sufficiently published and publicly disseminated back in 2002 to constitute prior art.  It could then re-file those IPRs, and try again.  Balanced against that, however, is that will take another six-plus months to get back to this point, i.e., an institution decision.

The other issue is whether this defect in Sandoz’s IPR of the ‘216 patent will infect any of its other pending IPRs.  Our review shows that Sandoz filed seven other IPRs against indication patents for Humira®.  Two of those IPRs also rely upon Humira® package inserts or Humira® labels as prior art, and thus, they are clearly susceptible to the same summary dismissal as the ‘216 IPR.  Thus, Sandoz’s denial of institution of the ‘216 patent likely spells the same for two more of its pending IPRs.

Sandoz’s IPR of the ‘100 patent (a formulation patent for Humira®) also has larger ramifications.  Amgen and Coherus Biosciences have also tried, and failed, to invalidate formulation patents covering Humira®.  Amgen attacked two patents with IPRs, U.S. Patents Nos. 8,916,157 and 8,916,158, and Coherus attacked U.S. Patent No. 9,114,166 with an IPR.  Together with Sandoz, these pending biosimilars have simply fortified four of AbbVie’s formulation patents covering Humira®. 

The consequences of fortifying Humira®’s formulation patents bolsters the likelihood that no biosimilar will enter before 2023.  Designing around a formulation patent for a biosimilar drug is not simple.  The proof for this, albeit indirect, is that so many biosimilars have preemptively attempted to invalidate these patents before contesting infringement in district court.  Unlike dosage form and strength, the BPCIA does not require that a biosimilar has the same formulation as the reference product. FDA has stated that the “differences between the formulation of a proposed product and the reference product may be acceptable.” Yet, the FDA has also stated that different formulations must nevertheless demonstrate the biosimilar is “highly similar to the reference product notwithstanding minor differences in clinically inactive components" and there are “no clinically meaningful differences between the biological product and the reference product in terms of safety, purity, and potency.”  By preemptively attacking the validity of the formulation patents suggests the biosimilars fear they will be infringed, because they have not been designed around.

AbbVie’s formulation patents do not expire before 2022.  That means, if the biosimilars will have trouble designing around those patents, and must mimic Humira®’s formulation, and yet these patents are increasingly immune from invalidating, and they don’t expire until 2022, then altogether, that slowly shores up the date before which AbbVie will settle – which is not likely to be before 2022.  This is consistent with AbbVie’s settlement with Amgen, for early 2023.  AbbVie’s earlier market assessment that Humira® will not face biosimilar competition until at least 2022 is slowly gaining evidence.