The U.S. Food and Drug Administration (FDA) has approved datopotamab deruxtecan-dlnk (Datroway, Daiichi Sankyo, Inc.), a Trop-2-directed antibody-drug conjugate, for adult patients with unresectable or metastatic hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer.

The approval is based on results from the TROPION-Breast01 clinical trial, a multicenter, open-label, randomized study involving 732 patients. Participants were randomized (1:1) to receive either Datroway or the investigator’s choice of chemotherapy, which included eribulin, capecitabine, vinorelbine, or gemcitabine.

Patients enrolled had experienced disease progression, were unsuitable for further endocrine therapy, and had undergone one or two prior lines of chemotherapy for unresectable or metastatic disease.

Median progression-free survival was 6.9 months in the Datroway group versus 4.9 months in the chemotherapy group. Median overall survival was 18.6 months for Datroway compared with 18.3 months for chemotherapy, with no statistically significant difference. The therapy achieved a confirmed objective response rate of 36% compared with 23% in the chemotherapy group. The median duration of response was 6.7 months for Datroway and 5.7 months for chemotherapy.

The most common side effects (20% or more) observed included stomatitis, nausea, fatigue, decreased blood counts (leukocytes, lymphocytes, neutrophils, and hemoglobin), and increased liver enzymes. Other notable reactions were alopecia, keratitis, dry eye, and gastrointestinal symptoms such as vomiting and constipation.

Datroway is administered as an intravenous infusion at a dose of 6 mg/kg (up to a maximum of 540 mg for patients weighing 90 kg or more) every 3 weeks (21-day cycle). 

Source: FDA