Dr. McArthur on the Implications of the ASCENT Trial in TNBC

Heather Lynn McArthur, MD, MPH, associate professor, the Department of Internal Medicine, member, Hematology and Oncology Division, UT Southwestern Medical Center, clinical director, the Breast Cancer Program, Simmons Cancer Center, discusses the implications of the phase 3 ASCENT trial (NCT02574455) in patients with advanced triple-negative breast cancer (TNBC).

In August 2021, the FDA granted regular approval to sacituzumab govitecan-hziy (Trodelvy) for patients with unresectable locally advanced or metastatic TNBC who have previously received 2 or more systemic therapies.

The regulatory decision was supported by findings from ASCENT, which was a confirmatory study evaluating the Trop-2–directed antibody drug conjugate (ADC) sacituzumab govitecan in patients with refractory or relapsed metastatic TNBC, McArthur begins. Patients were permitted to have had at least 2 prior lines of chemotherapy for advanced disease, and they were randomly assigned in a 1:1 fashion to receive either sacituzumab govitecan or the physician’s choice of chemotherapy. Chemotherapy choices included eribulin, capecitabine, gemcitabine, and vinorelbine, McArthur notes.

This patient population was heavily pretreated with a median of 3 prior anti-cancer treatment regimens, McArthur continues. Additionally, there was an improvement in both progression-free survival (PFS) and overall survival (OS), McArthur emphasizes. In the overall population, the PFS with sacituzumab govitecan was 4.8 months (95% CI, 4.1-5.8) vs 1.7 months (95% CI, 1.5-2.5) with chemotherapy (HR 0.43; 95% CI, 0.35-0.54). The median OS was 11.8 months (95% CI, 10.5-13.8) and 6.9 months (95% CI, 5.9-7.7) in the investigative and control arms, respectively (HR 0.51; 95% CI, 0.41-0.62).

In patients without brain metastases, the median PFS was 5.6 months (95% CI, 4.3-6.3) with sacituzumab govitecan and 1.7 months (95% CI, 1.5-2.6) with chemotherapy (HR, 0.41; 95% CI, 0.32-0.52). The median OS in this population was 12.1 months (95% CI, 10.7-14.0) for sacituzumab govitecan and 6.7 months (95% CI, 5.8-7.7) for chemotherapy (HR, 0.48; 95% CI, 0.38-0.59) , McArthur concludes.