Federal Circuit Affirms PTAB Finding that Rituxan® Biogen Patent is Invalid

As we previously reported, in October 2018, Pfizer persuaded the Patent Trial and Appeal Board (PTAB) that the claims of Biogen’s U.S. Patent No. 8,821,873, directed to a method of treating lymphoma with anti-CD20 antibodies and covering the cancer therapeutic RITUXAN (rituximab), were unpatentable on obviousness grounds. After appealing to the Federal Circuit, Biogen settled with Pfizer, which consequently declined to participate in the appeal.  Pfizer was replaced by the United States and subsequently the U.S. Patent and Trademark Office (USPTO) as an intervening party to defend the PTAB’s IPR decision. On December 6, 2019, the Federal Circuit heard oral arguments on behalf of Biogen and the USPTO.

On Wednesday, December 16, 2020, the Federal Circuit affirmed the PTAB’s ruling that US 8,821,873 is invalid as obvious. Pursuant to Federal Circuit Rule 36, the judgment was issued without opinion.