CAP TODAY Pathology/Laboratory Medicine/Laboratory Management
February 2020—The FDA granted accelerated approval to Enhertu (fam-trastuzumab deruxtecan-nxki) for the treatment of adults with unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2–based regimens in the metastatic setting. Enhertu is a human epidermal growth factor receptor 2–directed antibody and topoisomerase inhibitor conjugate.
Enhertu’s approval was based on the results of a clinical trial enrolling 184 female patients with HER2-positive, unresectable and/or metastatic breast cancer who had received two or more prior anti-HER2 therapies in the metastatic setting. These patients were heavily pretreated in the metastatic setting, receiving between two and 17 therapies prior to receiving Enhertu. Patients in the clinical trial received Enhertu every three weeks and tumor imaging was obtained every six weeks. The overall response rate was 60.3 percent, which reflects the percentage of patients that had a certain amount of tumor shrinkage with a median duration of response of 14.8 months.