Aditya Bardia, MD, MPH, Mass General Cancer Center, Boston, Massachusetts, shares the results of a second interim analysis from the TROPiCS-02 trial, evaluating sacituzumab govitecan for patients with hormone receptor-positive, human epidermal growth factor 2-negative (HR+/HER2−) advanced breast cancer who had already received 2 to 4 lines of chemotherapy. Previously reported results from this phase 3 trial have showed an improvement to progression-free survival and overall survival with sacituzumab govitecan, compared to physician’s choice of chemotherapy.

At the 2022 San Antonio Breast Cancer Symposium, Dr Bardia presented the biomarker results which showed the benefit with sacituzumab govitecan was seen regardless of Trop-2 expression. With these results in mind, Dr Bardia stated that Trop-2 expression should not be used as a biomarker selection strategy for sacituzumab govitecan.

Transcript:

Hi, I am Aditya Bardia, Breast Medical Oncologist at Mass General Cancer Center, Harvard Medical School, Boston. I was involved with the TROPiCS-02 trial. At San Antonio Breast Cancer Symposium 2022, we saw the updated results from TROPiCS-02, related to biomarkers. As a reminder, the TROPiCS-02 trial evaluated sacituzumab govitecan, a Trop-2 directed antibody drug conjugate for patients with pre-treated hormone receptor-positive metastatic breast cancer. In the clinical trial, sacituzumab govitecan was compared with standard chemotherapy.

Patients needed to have received at least 2 prior lines of chemotherapy. So essentially it was a third-line-plus study comparing sacituzumab govitecan to chemotherapy of physician's choice, which could be navelbine, eribulin, as well as other options. The primary end point was progression-free survival and a key secondary end point was overall survival. At ASCO 2022, we saw the first results from TROPiCS-02, which showed that there was improvement in progression-free survival with sacituzumab govitecan was a standard chemotherapy. At ESMO 2022, we saw the overall survival results, again, improvement in overall survival with sacituzumab govitecan was a standard endocrine therapy.

At San Antonio Breast Cancer Symposium 2022, we see the biomarker results looking at Trop-2 expression, which is the target of sacituzumab govitecan and impact on clinical outcomes. The bottom line is that the benefit with sacituzumab govitecan was seen regardless of Trop-2 expression. In tumors with high Trop-2 expression, the overall survival and progression-free survival was superior with sacituzumab govitecan as compared to standard chemotherapy and also in low Trop-2 expressing tumors, the benefit with sacituzumab govitecan was seen as compared to standard chemotherapy.

Trop-2 should not be used as a biomarker selection strategy for therapy selection with sacituzumab govitecan because the benefit in this setting is seen regardless of Trop-2 expression.

Source:

Rugo H, Bardia A, Marmé F. “Sacituzumab Govitecan (SG) vs Treatment of Physician’s Choice (TPC): Efficacy by Trop-2 Expression in the TROPiCS-02 Study of Patients (Pts) With HR+/HER2– Metastatic Breast Cancer (mBC).” Presented at: San Antonio Breast Cancer Symposium; December 6 – 10, 2022; San Antonio, Texas. Abstract: GS5-11