Cancer Drugs Approved on the Basis of a Surrogate End Point and Subsequent Overall Survival

Abstract

Most contemporary approvals of new cancer drugs are made on the basis of a surrogate end point, such as response rate or progression-free survival (PFS).¹ When the approval is based on a surrogate end point, subsequent studies are advised and often obligated to clarify the drug’s effect on overall survival. One such drug is bevacizumab, which received accelerated approval on the basis of PFS for patients with metastatic breast cancer. Later findings revealed no improvement in overall survival and significant toxicity, which required a removal of marketing authorization.²