Enhertu(fam-trastuzumab deruxtecan-nxki)

Enhertu (fam-trastuzumab deruxtecan-nxki) is a Biologics License Application (BLA 351(a)) that received Priority Review from the FDA. The recommended regulatory action was Accelerated Approval for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens in the metastatic setting. The application was submitted and received on August 29, 2019, with a PDUFA Goal Date of April 29, 2020.

Key efficacy findings include an Objective Response Rate (ORR) of 60.3%, with a Complete Response Rate of 4.3% and a Partial Response Rate of 56%. The median Duration of Response (DoR) was 14.8 months. In specific patient populations, the confirmed ORR was 61% in patients with prior pertuzumab and 52% in patients without prior pertuzumab. For hormone receptor-positive patients, the confirmed ORR was 54%, and for hormone receptor-negative patients, it was 65%.

Notable safety findings include a 4.3% fatality rate due to adverse reactions, with 2.6% of fatalities attributed to interstitial lung disease (ILD). The incidence of adjudicated ILD was 9.4%, and the median time to first onset of ILD was 4.1 months. Serious adverse reactions occurred in 20% of patients.