A brief review of Trop-2 directed therapy and its role in the HR+ metastatic breast cancer treatment landscape.
Transcript:
Jules Cohen, MD: What about sacituzumab govitecan[antibody drug conjugate] and ER-positive disease?
Neil M. Iyengar, MD: We have data from the TROPiCS-02 trial that Hope S. Rugo, MD, FASCO, presented. We see a benefit in the ER-positive population. Sacituzumab has been approved for use in the triple-negative population. I think we can consider our patients who have progressed on multiple lines of endocrine therapy as essentially being endocrine resistant and similar to the triple-negative population. It was encouraging to see the benefit of sacituzumab in that population. Now, notably, the population that was included in TROPiCS-02 included a subgroup of patients with HER2-low expression as well. We have seen data that’s stratified by HER2 expression IHC [immunohistochemistry] status and there was a consistent benefit across the different IHC levels of HER2 disease in the TROPiCS-02 trial. Then, here at San Antonio, we also saw data stratified by Trop2 expression. Trop2 expression was not predictive of the benefit with sacituzumab, which is consistent with earlier data, as well. That formed the rationale to not selecting patients by Trop2 status for the TROPiCS-02 trial. This is another ADC [antibody drug conjugate] that we can offer our patients who are endocrine therapy resistant. In terms of sequencing, we need to see more data to support the optimal sequencing strategy of ADCs. In patients who are HER2-low, my preference is to favor trastuzumab deruxtecan and perhaps use sacituzumab later on. Certainly, for those patients who are HER2-zero, we’d be using sacituzumab for now, until we start to see whether or not some of those HER2-zero patients are actually HER2 ultra-low.
Transcript edited for clarity.