In a Final Written Decision issued on October 3, 2018 of an inter partes review initiated by Pfizer (IPR2017-00737) challenging the patentability of claims 1–17 of U.S. Patent No. 7,892,549 B2 entitled, “Treatment with Anti-ErbB2 Antibodies”, the Patent Trials and Appeal Board (PTAB) found that each of the challenged claims are unpatentable as set forth in the petition. In a separate challenge by Celltrion (IPR2017-01122), the PTAB also concluded that the patent would have been obvious over the combination Baselga 1996, Seidman 1996, Pegram, and the 1995 TAXOL PDR.

The patent covered a method for the treatment of patients with breast cancer that overexpresses the ErbB2 receptor, comprising administering a combination of an antibody that binds ErbB2 (e.g. trastuzumab), a taxoid (e.g. Taxol) and a further growth inhibitory agent.