Facing eleventh-hour manufacturing problems of a sort that can easily derail a drug, Genentech Inc. worked with FDA to devise a plan that enabled the agency to grant full approval for Perjeta pertuzumab for first-line HER2-positive metastatic breast cancer without a delay.

FDA was able to take the unusual step of approving a drug whose manufacturing process is not assured in part because of the availability of an undisclosed amount of the drug manufactured before the problems began, and because of a postmarketing plan detailing steps Genentech will take to resume and validate Perjeta manufacturing.