Phase III Trial of Sacituzumab Govitecan in HR-Positive, HER2-Negative Advanced Breast Cancer

By: Joshua Swore, PhD
Posted: Tuesday, January 24, 2023

Sacituzumab govitecan-hziy demonstrated a statistically significant benefit in progression-free survival over chemotherapy in patients with hormone receptor (HR)-positive, HER2-negative advanced breast cancer, according to an article published in the Journal of Clinical Oncology. “This novel agent directed to a highly expressed target may represent an important treatment option for these patients, addressing a critical unmet medical need,” said author Hope Rugo, MD, of the University of California, San Francisco, and colleagues.“[Sacituzumab govitecan] is a preferred therapy option for patients with HR-positive/HER2-negative cancers after prior treatment including endocrine therapy, a CDK4/6 [inhibitor], and at least two lines of chemotherapy (including a taxane) for advanced breast cancer.”

The global phase III TROPiCS-02 trial enrolled 543 patients with HR-positive, EGFR-negative breast cancer. Patients were randomly assigned to two arms of the study, with 272 receiving sacituzumab govitecan and 271 receiving chemotherapy. The median patient age was 56 years, 95% had visceral metastases, and 99% had received a prior CDK4/6 inhibitor with three lines of chemotherapy.

The authors reported a median progression-free survival of 5.5 months with sacituzumab govitecan and 4.0 months with chemotherapy. Landmark analysis revealed longer progression-free survival among patients treated with sacituzumab govitecan at both 6 and 12 months (46% vs. 30% and 21% vs. 7%, respectively). Objective response was also found to be higher with sacituzumab govitecan versus chemotherapy (21% vs. 14%). As for toxicity, 51% of patients treated with sacituzumab govitecan experienced grade ≥ 3 neutropenia, and 9% reported diarrhea, compared with 38% and 1%, respectively, of those treated with chemotherapy.

“Benefit with sacituzumab govitecan was seen across most of the prespecified subgroups, including patients who received at least three prior chemotherapies for metastatic disease, had visceral metastases, and were age 65 years or older,” the investigators stated. “The overall survival results (16% reduction in risk of death; P = .14) are not yet mature in the first planned interim analysis.”

Disclosure: For full disclosures of the study authors, visit ascopubs.org.

Journal of Clinical Oncology

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