Abstract
<jats:p><div>Abstract Purpose:<p>Patients with endometrial cancer who progress after chemotherapy/immunotherapy have limited treatment options. We evaluated the activity and safety of sacituzumab govitecan (SG), a Trop-2–directed antibody–drug conjugate, in patients with advanced/recurrent endometrial cancer, including carcinosarcoma.</p> Patients and Methods:<p>This was a phase II, two-stage, open-label, investigator-initiated trial of patients with persistent/recurrent endometrial cancer who had progressed following ≥1 prior chemotherapy. Patients received SG 10 mg/kg on days 1 and 8 every 3 weeks. The primary endpoint was objective response rate (ORR) by RECIST v1.1. Secondary endpoints included clinical benefit rate [CBR = complete response (CR) + partial response (PR) + stable disease ≥ 6 months], duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. Trop-2 expression was analyzed by immunohistochemistry as an H-score.</p> Results:<p>Fifty patients were screened, and 21 enrolled during stage 1; 34 patients were screened, and 29 enrolled during stage 2; 84% (<i>n</i> = 42) of the patients harbored serous carcinoma, carcinosarcoma, or grade 3 endometrioid tumors. Patients received a median of two prior therapies (range, 1–4) and 50% had failed pembrolizumab/dostarlimab. At a median follow-up (range) of 11 (2.9–65.5) months, the ORR was 28% [95% confidence interval (CI), 16%–42%], including CRs (4%) and PRs (24%). The median DOR (95% CI) was 9.3 (2–12.9) months, with four still responding. The CBR was 52% (26/50). The median PFS and OS were 5.5 (95% CI, 3.7–7.4) and 17.5 (95% CI, 10.4–22.2) months, respectively. Grade 3 to 4 toxicity occurred in 88% with no attributable deaths. Mean H-scores did not predict response.</p> Conclusions:<p>SG demonstrated encouraging efficacy in a pretreated population that included biologically aggressive recurrent endometrial cancer. Adverse events were consistent with the known safety profile.</p></div></jats:p>