As we previously reported, the district court granted Sandoz’s motion for summary judgment of non-infringement in the ongoing Amgen v. Sandoz litigation, which relates to Sandoz’s filgrastim and pegfilgrastim biosimilars. Amgen filed its opening Federal Circuit appeal brief in May, arguing that the district court made several errors in its construction of the asserted claims of Amgen’s ‘878 patent on protein purification and Amgen’s ‘427 method of treatment patent. Sandoz filed its responsive brief on June 22 to counter these assertions.
Sandoz first responds to Amgen’s argument that the district court modified its construction of claim 7 of the ‘878 patent at the summary judgment stage. Specifically, Amgen argued that the district court created a requirement that the claim’s “washing” and “eluting” elements refer to separate steps using different solutions in the protein purification process, where the court had not previously interpreted the claim to include such a limitation. Sandoz responds that Amgen did not challenge this interpretation during claim construction proceedings, and therefore waived its right to contest the construction on appeal. Further, Sandoz contends that the terms “washing” and “eluting” necessarily refer to discrete, sequential steps because the proteins must be washed of contaminants before they can be eluted from the separation matrix. According to Sandoz, the court therefore correctly found that Sandoz did not literally infringe claim 7 of the ‘878 patent. Sandoz further argues that the court correctly found no infringement under the doctrine of equivalents, because Amgen failed to provide any evidence to show functional equivalence between the Sandoz and Amgen protein purification methods.
Sandoz separately argues that the district court properly denied Amgen’s motion for continued discovery on the ‘878 patent relating to Sandoz’s plans to replace a discontinued ingredient in its separation solution, because the change in ingredient does not affect the protein purification process itself and therefore is not material to the judgment of non-infringement.
With respect to the ‘427 patent, Sandoz argues that the district court correctly construed the phrase “a disease treating-effective amount of at least one chemotherapeutic agent” in claim 1 to exclude stem cell mobilization used only to alleviate the side effects of a disease treatment. According to Sandoz, claim 1 of the ‘427 patent is directed only towards a chemotherapeutic agent that serves as an independent treatment for a disease. The district court adopted Sandoz’s construction and entered a non-infringement judgment. On appeal, Sandoz argues that its interpretation is true to the plain meaning of the claim and consistent with the claim’s specifications, and asks for the non-infringement judgment to be upheld accordingly.
Stay tuned to Big Molecule Watch for further developments in this case and other BPCIA litigations.
