Even Split on OS vs. PFS As Primary Endpoint for Cancer Drug Approvals
As many GEN poll voters agree as disagree that the primary endpoint for approval of cancer drugs should change to progression-free survival (PFS) from overall survival (OS), with 15.8% undecided. FDA’s recent success in removing Avastin’s metastatic breast cancer (MBC) indication re-ignited a longstanding debate in drug development circles over what the primary endpoint should be. Avastin’s initial accelerated approval, in combination with paclitaxel, for MBC was based on PFS data. But last year FDA’s CDER recommended that MBC be withdrawn since subsequent studies showed only a small improvement in OS. FDA noted that Avastin’s PFS improvement was not worth the risk of associated side effects. Avastin maker Genentech and parent Roche countered that PFS should be the primary endpoint, because it could be objectively measured and because the EU recognized it as an oncology endpoint.