Carla Mouta-Bellum

This article analyzes obviousness issues related to antibody patents at the Patent Trials and Appeal Board (PTAB) and in federal courts. We review several cases categorized by type of claims in search of trends on what types of antibody-related claims are more likely to survive an obviousness challenge… These cases are highly fact-specific, but a few broad observations may be made. To our knowledge, no claims directed to an antibody claimed purely by structure have been challenged, except for those of an ADC (KADCYLA®), where both the antibody part and the drug part of the conjugate were previously known. An antibody broadly claimed by function may be considered obvious “[i]f any one method of achieving any single embodiment [of such claim] would have caused a person of ordinary skill in the art to anticipate success.” Abbott GMBH, 971 F. Supp.2d at 186. Objective indicia of nonobviousness have been helpful, but only where there was a clear nexus between the objective evidence and the claims.

Immunotherapy has emerged as one of the most promising mechanisms to combat diseases like cancer and microbial infections. Since 2000, multiple antibody drugs have reached blockbuster status, including the anti-TNF antibodies adalimumab and infliximab, the anti-CD20 antibody rituximab, the anti-VEGF-A antibody bevacizumab, and the anti-HER-2 antibody Trastuzumab. In 2016, five of the top 10 pharmaceuticals were antibody drugs, with combined sales exceeding $45.8 billion. The cancer immunotherapy market is expected to reach nearly $120 billion… The promise of immunotherapy as a treatment option has opened up the intellectual property landscape of the field. Many companies and institutions have filed patent applications related to the various drugs and targets… The claim language in a patent is crucial to the effective protection of the invention, and the balance between breadth of the claims and validity is a difficult one to achieve.