Ahead of an FDA Decision on Its Pegfilgrastim Biosimilar, Sandoz Sues Amgen

This month, biosimilar developer Sandoz filed suit against Amgen, asking the United States district court for the Northern District of California for a declaratory judgment of patent noninfringement and invalidity.

The suit relates to Amgen’s US patent number 9,643,997 (the ’997 patent), which relates to processes for purifying proteins and capturing those proteins by a separation matrix. Sandoz and Amgen already litigated a similar patent, US patent number 8,940,878 (the ’878 patent), in relationship to Sandoz’s manufacturing process for its filgrastim biosimilar, Zarxio, and its pegfilgrastim biosimilar, which is pending an FDA decision and which is approved in the European Union under the trade name Ziextenzo. In the prior case, in 2017, the court granted a summary judgment of noninfringement of the ’878 patent.

According to the new complaint, the ’997 patent and the ’878 patent are in the same patent family and are similar or even identical in many respects. The only differences between the patents, says Sandoz’s complaint, are ones that do not relate to the grounds on which Sandoz successfully gained a summary judgment of noninfringement in the prior litigation.

The complaint indicates that Sandoz discovered the similarity between the 2 patents and asked Amgen in 2017 to litigate claims related to the ’997 patent together with those of the ’878 patent. However, Sandoz says that Amgen did not amend its litigation to include the ’997 patent and has now allowed 20 months to elapse without taking action on the matter.

Despite not yet having alleged infringement of the ’997 patent, “Amgen has not disavowed the intention to seek a preliminary injunction,” said the Sandoz complaint, adding that the suit seeks to “…ensure that any issues with respect to the ’997 patent, including any preliminary injunction motion, are resolved promptly, efficiently, and well in advance of the launch of Sandoz’s pegfilgrastim product.”

Sandoz gave Amgen its 180-day notice that it plans to begin commercially marketing the biosimilar pegfilgrastim in the United States at its earliest opportunity.

The Sandoz pegfilgrastim biosimilar received a complete response letter from the FDA in July 2016, after which Sandoz worked with the agency to address its concerns. Sandoz agreed with the FDA to undertake an additional study to resolve the agency’s outstanding questions with an eye toward a 2019 resubmission of its Biologics License Application.