Filgrastim PTAB Update

As we previously reported, earlier this year Kashiv Biosciences filed two inter partes review (IPR) petitions challenging certain claims of Amgen’s U.S. Patent Nos. 8,940,878 and 9,643,997, which are directed to methods to purify proteins expressed in a non-native soluble form in a non-mammalian expression system.  Amgen is asserting the ’878 and ’997 patents, as well as U.S. Patent No. 9,856,287, against Kashiv in their BPCIA litigation concerning Kashiv’s proposed biosimilar of NEUPOGEN (filgrastim). On September 11, 2019, the PTAB granted both petitions and instituted IPR proceedings for both challenged patents (IPR2019-00791 and IPR2019-00797). The PTAB also scheduled oral argument, if requested, for June 11, 2020 in both matters.

Kashiv is also challenging the ’287 patent in patent office proceedings.  In April, the PTAB instituted a post-grant review (PGR) proceeding against the ’287 patent and scheduled it for oral argument, if requested, on January 29, 2020 (PGR2019-00001).  Apotex was originally a co-petitioner in that PGR but in August withdrew from the PGR and requested an adverse judgment against itself.

As we have reported, Fresenius Kabi is separately challenging claims of the ’287 and ’997 patents through IPR petitions that it filed this past April (IPR2019-00971) and June (IPR2019-01183), respectively. Both petitions are still pending institution determinations.