A Federal Circuit panel seemed to resist Genentech Inc.’s efforts Wednesday to pull a generic Amgen Inc. cancer treatment off the shelves for six months.

Genentech told a Federal Circuit panel that Amgen failed to serve the 180 day notice of commercial marketing required by the Biologics Price Competition and Innovation Act (BPCIA) when, in August 2018, it supplemented its Food and Drug Administration application for Mvasi, Amgen’s biosimilar version of Genentech’s $3 billion a year drug Avastin.