Sacituzumab Govitecan in Metastatic Triple-Negative Breast Cancer
In heavily pretreated patients with metastatic triple-negative breast cancer, the antibody-drug conjugate sacituzumab govitecan was well tolerated and induced early and durable responses, according to a study in the Journal of Clinical Oncology. This agent targets Trop-2, which is expressed in most triple-negative breast cancers. Based on these early findings, the investigators conclude that Trop-2 warrants further research as a therapeutic target and predictive biomarker.
In a single-arm, multicenter trial of 69 patients with relapsed or refractory metastatic triple-negative breast cancer, the confirmed objective response rate was 30%, with 19 partial responses and 2 complete responses. The median duration of response was 8.9 months (95% confidence interval, 6.1–11.3 months), and the clinical benefit rate (complete response plus partial response plus stable disease ≥ 6 months) was 46%. And these responses occurred early, with a median onset of 1.9 months.
As for toxicity, grade ≥ 3 adverse events included neutropenia (39%), leukopenia (16%), anemia (14%), and diarrhea (13%). The incidence of febrile neutropenia was 7%.