MONDAY, Dec. 23, 2019 -- Enhertu (fam-trastuzumab deruxtecan-nxki) has received accelerated approval for treatment of unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer, the U.S. Food and Drug Administration announced Friday.
Enhertu, a HER2-directed antibody and topoisomerase inhibitor conjugate, is indicated for adults with unresectable or metastatic HER2-positive breast cancer who have received at least two previous anti-HER2-based regimens in the metastatic setting. The recommended dosage of Enhertu is an intravenous infusion of 5.4 mg/kg once every three weeks (21-day cycle) until disease progression or unacceptable toxicity.
Approval of Enhertu was based on clinical data from 184 women with HER2-positive unresectable and/or metastatic breast cancer who had previously received two to 17 anti-HER2 therapies in the metastatic setting. Patients received Enhertu every three weeks and underwent tumor imaging every six weeks. The researchers found an overall response rate of 60.3 percent and a median response duration of 14.8 months.
Prescribing information for Enhertu includes a Boxed Warning advising health care providers about the risks for interstitial lung disease (ILD) and embryo-fetal toxicity. Patients have reported ILD and pneumonitis with Enhertu treatment, and some cases have resulted in death. Enhertu should be permanently discontinued in patients with grade 2 or higher ILD or pneumonitis. The most commonly reported side effects of Enhertu include nausea, fatigue, vomiting, alopecia, constipation, decreased appetite, anemia, decreased neutrophil count, diarrhea, leukopenia, cough, and decreased platelet count. Enhertu may also carry the risk for left ventricular dysfunction, which has been shown with other HER2-directed therapies for breast cancer.
Approval was granted to Daiichi Sankyo.