Multicenter phase 3 trial of sacituzumab tirumotecan for previously treated metastatic triple-negative breast cancer

The multicenter phase 3 OptiTROP-Breast 01 trial in China compared the antibody-drug conjugate sacituzumab tirumotecan (sac-TMT) versus chemotherapy in patients with locally recurrent or metastatic TNBC who had received two or more prior therapies, including at least one for metastatic disease. The primary endpoint was progression-free survival. Median PFS was 6.7 months with sac-TMT versis 2.5 months with chemotherapy (HR 0.32; p<0.00001), whereas median overall survival was not reached with sac-TMT versus 9.4 months with chemotherapy (HR 0.53; p=0.0005). The percentage of patients with an objective response was 45.4% with sac-TMT and 12.0% with chemotherapy, with duration of response 7.1 months and 3.0 months, respectively. The most common treatment-related adverse event with sac-TMT was hematologic toxicity. The authors conclude that sac-TMT demonstrated statistically significant and clinically meaningful improvement in PFS, compared to chemotherapy, with a manageable safety profile.