for patients with unresectable, locally advanced or metastatic hormone receptor (HR)–positive, HER2-negative breast cancer after endocrine-based therapy and at least two additional systemic therapies for metastatic disease.
Label expansion for the Trop-2–directed antibody-drug conjugate was based on the TROPICS-02 trial, which randomized 543 adults 1:1 to either sacituzumab govitecan 10 mg/kg IV on days 1 and 8 of a 21-day cycle or single agent chemotherapy, most often eribulin but also vinorelbine, gemcitabine, or capecitabine.
Median progression free survival was 5.5 months with sacituzumab govitecan versus 4 months with single agent chemotherapy (hazard ratio, 0.66; P = .0003). Median overall survival was 14.4 months in the sacituzumab govitecan group versus 11.2 months with chemotherapy (HR, 0.79), according to an FDA press release announcing the approval.
In a Gilead press release, Hope Rugo, MD, a breast cancer specialist at the University of California, San Francisco, and principal investigator for TROPICS-02, said the approval “is significant for the breast cancer community. We have had limited options to offer patients after endocrine-based therapy and chemotherapy, and to see a clinically meaningful survival benefit of more than 3 months with a quality-of-life benefit for these women is exceptional.”
The most common adverse events associated with sacituzumab govitecan in the trial, occurring in a quarter or more of participants, were decreased leukocyte count, decreased neutrophil count, decreased hemoglobin, decreased lymphocyte count, diarrhea, fatigue, nausea, alopecia, glucose elevation, constipation, and decreased albumin.
Labeling for the agent carries a boxedwarning of severe or life-threatening neutropenia and severe diarrhea.
The recommended dose is the trial dose: 10 mg/kg IV on days 1 and 8 of 21-day cycles until disease progression or unacceptable toxicity.
Sacituzumab govitecan was previously approved for unresectable, locally advanced or metastatic triple-negative breast cancer after two or more prior systemic therapies and locally advanced or metastatic urothelial cancer after platinum-based chemotherapy and either a PD-1 or PD-L1 inhibitor.
A version of this article first appeared on Medscape.com.