Parties Agree That Mylan's Pegfilgrastim Biosimilar Does Not Infringe Amgen's Patent

Amgen, maker of the brand-name pegfilgrastim (Neulasta), and Mylan, which partnered with Biocon to develop a biosimilar (Fulphila), have entered a joint status report in the District Court for the Western District of Pennsylvania. In the status report, they agree that Amgen cannot maintain a claim of infringement against Mylan with respect to US Patent Number 8,273,707, which covers a process for purifying proteins by mixing a protein preparation with a solution involving 2 salts.

This latest development stems from an earlier decision in another case related to the same patent; in March 2018, a Delaware court dismissed a lawsuit brought by Amgen over a different biosimilar developer’s alleged infringement of this same patent; in that case, Amgen alleged that Coherus BioSciences infringed on its patent because Coherus’ biosimilar pegfilgrastim, later approved as Udenyca, mixed salts that, in combinations, were equivalent to Amgen’s patented combinations. According to the court, Amgen had previously acknowledged that Coherus did not literally infringe on the patent.

Later, in July 2019, the federal circuit affirmed that decision, saying that Amgen “clearly and unmistakably surrendered salt combinations other than the particular combinations recited in the claims.”

In this month’s joint status report in the case concerning Fulphila, the parties write that, in light of the court’s precedential decision in Amgen v Coherus BioSiences, Agmen and Mylan agree that Amgen can no longer maintain its claim related to this patent.

The stipulation has no impact on the claims of another patent—US Patent Number 9,643,997—that Amgen alleges Mylan has infringed. This patent covers processes for purifying proteins expressed in nonmammalian systems.

Mylan, however, requested that the court extend a stay on discovery related to the latter patent for an additional 30 days. Last month, another biosimilar developer, Sandoz, filed a response to Amgen’s petition for a rehearing of Amgen v Sandoz, a case in which the federal circuit sided with Sandoz related to alleged infringement of the patent. In light of the pending decision in that matter, the court agreed to stay further action in this case pending further order of the court.