On April 22, 2020, the US Food and Drug Administration (FDA) granted an accelerated approval to Trodelvy® (sacituzumab govitecan-hziy) for the treatment of patients with metastatic triple-negative breast cancer who received at least two prior treatments for metastatic disease. Sacituzumab govitecan is composed of an anti-TROP-2 humanized IgG1 antibody conjugated to the topoisomerase inhibitor SN38, which is the active metabolite of irinotecan.
The approval was based on the results of a clinical trial of 108 patients with metastatic triple-negative breast cancer who had received at least two prior treatments for metastatic disease. In this study, the overall response rate was 33.3%, with a median duration of response of 7.7 months. Of the patients who responded to treatment, 55.6% maintained their response for 6 or more months and 16.7% maintained their response for 12 or more months.
The accelerated approval program allows FDA to approve drugs for serious conditions to fill an unmet medical need based on a surrogate endpoint, i.e., a result that is reasonably likely to predict a clinical benefit to patients. Additional clinical trials are required to confirm Trodelvy’s clinical benefit, and the FDA can remove the drug from the market if the confirmatory trial does not show that the drug provides clinical benefit.