The response rate of alternative treatments for drugs approved on the basis of response rate

Abstract

We assessed the frequency that oncology drugs approved by the U.S. Food and Drug Administration (FDA) based on a single-arm study when there is already evidence of existing and available treatments. For this, we conducted a retrospective cross-sectional analysis of FDA-approved oncology drugs based on a single-arm study. All FDA announcements for all oncology drugs approved from May 2014 through June 2019 on a single-arm trial were included. We then performed a systematic search in PubMed, looking for studies on other drugs for the same indication as the FDA drug approval. For the 60 indications, we found 38 instances (63%) of existing therapies being used for the same indication. Of those, we found that 20 drugs were approved based upon a response rate lower than response rates of existing therapies in the same indication. Among oncology drugs that were FDA-approved based on a single-arm study, we found evidence of existing, available therapies being used for the same indication as the FDA-approved drug in the majority of indications (63%), and in one-third of all indications, the response rates for existing therapies were numerically better than the FDA-approved drug. These results suggest that there are inconsistencies in the standards set for oncology drug approvals, and many uncontrolled trials leading to drug approvals could have contemporary controls for which equipoise exists.