Data Demonstrate Survival Benefit of Sacituzumab Govitecan In Metastatic Triple-Negative Breast Cancer Regardless of HR/HER2 Status

New phase 3 study findings show improved progression-free survival (PFS), overall survival (OS), and objective response rates (ORR) among patients with relapsed or refractory metastatic triple-negative breast cancer (TNBC) who received 2 or more prior systemic therapies, including one for metastatic disease.

TNBC is the most aggressive form of breast cancer and accounts for approximately 15% of all breast cancer diagnoses. The study authors noted that it is diagnosed more frequently in younger and premenopausal women and is more prevalent in Black and Hispanic women. It also has a higher risk of recurrence and metastases than other breast cancer types, with an average time to metastatic recurrence of approximately 2.6 years compared with 5 years for other breast cancers.

The analysis included 146 patients with brain metastases who were eligible for chemotherapy and who had an original breast cancer diagnosis that was not TNBC. Of those, 70 received sacituzumab govitecan and 76 received physician’s choice of chemotherapy.

“In the metastatic stage of breast cancer, it is not uncommon for people to change from one subtype to another,” said Javier Cortes, MD, head of the International Breast Cancer Center, in a press release. “Roughly one-third of patients with TNBC in the ASCENT study were not originally diagnosed with TNBC, and they still experienced a survival benefit with Trodelvy compared with chemotherapy. For treating physicians, this reinforces Trodelvy’s efficacy in more complex patients.”

According to the press release, patients receiving sacituzumab govitecan had a median PFS of 4.6 months compared to 2.3 months in the chemotherapy arm. Patients in the investigative arm also had a median OS of 12.4 months compared to 6.7 months in the chemotherapy arm, and an ORR of 31% compared with 4%. The outcomes in this subgroup were similar to those in the overall ASCENT trial population.

The safety profile of sacituzumab govitecan in this subgroup was also consistent with prior findings from the ASCENT study. Important treatment-related grade 3 or higher adverse events for sacituzumab govetican compared with chemotherapy included neutropenia (59% vs. 40%), leukopenia (12% vs. 9%), anemia (8% vs. 7%), and diarrhea (7% vs. 0%). There were no treatment-related deaths in the sacituzumab govitecan treatment arm.

“Trodelvy is already transforming outcomes for patients with second-line or later metastatic TNBC,” said Bill Grossman, MD PhD, senior vice president of oncology clinical research at Gilead Sciences, in the press release.

REFERENCE

New Data Demonstrate Trodelvy Survival Benefit in Metastatic Triple-Negative Breast Cancer Patients Regardless of Initial HR/HER2 Status. News release. Gilead; September 16, 2021. Accessed September 21, 2021. https://www.gilead.com/news-and-press/press-room/press-releases/2021/9/new-data-demonstrate-trodelvy-survival-benefit-in-metastatic-triple-negative-breast-cancer-patients-regardless-of-initial-hrher2-status