As reported in Fierce Biotech earlier today, Amgen announced the results of a Phase III clinical trial of its biosimilar drug (designated ABP 501) for moderate-to-sever plaque psoriasis conducted in comparison with adalimumab (sold by AbbVie as Humira®).  Amgen's press release asserted that the study, aimed at assessing safety and efficacy of Amgen's biosimilar, "met its primary endpoint" compared with Humira®, where that primary endpoint was evaluated by the Psoriasis Area and Severity Index (PASI).  The result showed improvement "within the prespecified equivalence margin for ABP 501 compared to adalimumab" and that safety and efficacy of Amgen's drug were comparable to AbbVie's drug.

Adalimumab is a human antibody that recognizes tumor necrosis factor-alpha (TNF-α) developed by collaboration between BASF and Cambridge Antibody Technologies and first approved as a treatment for rheumatoid arthritis (RA) on December 31, 2002.  The drug has been approved thereafter for additional indications, including psoriatic arthritis, ankylosing spondylitis, Crohn's disease, ulcerative colitis, psoriasis and juvenile idiopathic arthritis.  The drug costs an estimated $1,662 per month and had 2012 sales of $4.3 billion in the U.S. and $9.3 billion worldwide.

The drug is protected by at least U.S. Patent No. 6,090,923, which was granted on July 18, 2000 on an application filed in 1991; the patent will thus expire on July 18, 2017.  Under the provisions of the BPCIA (that portion of the omnibus healthcare reform act commonly called "Obamacare"), AbbVie's market exclusivity expires at the end of this year.  There is no indication that Amgen has filed an application for biosimilar approval under 42 U.S.C. § 262(k) nor that it will file such an application prior to expiry of AbbVie's market exclusivity.  Accordingly, there will be no opportunity for AbbVie to invoke the patent litigation provisions of the Act, unless of course the company has other patents it can identify according to these litigation provisions.

This scenario follows closely the scenario forecast by the Federal Trade Commission during debate over the provisions of the Act; the FTC predicted that, unlike "traditional" generic drug companies it would be more established, conventionally innovator and branded biologic drug companies that would enter the biosimilars market.  The FTC also predicted that reductions in biologic drug costs would be in the range of 20-30% of the innovator biologic drug costs which, while a significant savings is much less than the experience with small molecule generic drugs.  It also remains to be seen whether Amgen's drug, or any other biosimilar drug will be able to satisfy the as yet unenunciated standards for interchangeability, which would make any such biosimilar drug much more attractive in the marketplace.