Today, Amgen filed a complaint in the District of Delaware against Hospira and its parent Pfizer alleging infringement of U.S. Patent No. 9,643,997 based on Hospira’s filing of an aBLA seeking FDA-approval to engage in the commercial manufacture, use or sale of a biosimilar of Neupogen® (filgrastim). The ’997 patent is directed to a protein purification process, and is also being asserted by Amgen in its BPCIA litigations against Mylan concerning its Fulphila® (pegfilgrastim-jmdb) biosimilar of Neulasta®, and against Adello concerning its proposed filgrastim biosimilar.

According to the complaint, the parties engaged in the patent dance, during which the parties negotiated and ultimately agreed that, of the seven patents that Amgen identified on its list of potentially infringed patents, only the ’997 patent would be the subject of an action for patent infringement under 42 U.S.C. § 262(l)(6).

This case marks the fourth BPCIA litigation concerning a filgrastim biosimilar, following Amgen suits against Sandoz, Apotex and Adello.