The objective of this article is to evaluate the anticancer effectiveness and safety of dostarlimab in patients with endometrial cancer with inadequate mismatch repair.

Part 1 of this continuing, open-label, single-group, multicenter research began on March 7, 2016, and patients with inadequate mismatch mutation repair endometrial cancer began enrolling on May 8, 2017. The average follow-up time was 11.2 months. The statistical study was carried out from July 8 to August 9, 2019.


Dostarlimab 500 mg intravenously every 3 weeks for 4 doses, then 1000 mg every 6 weeks until disease progression, therapy termination, or withdrawal. The primary end goal was determined by a blinded independent central review using the Response Evaluation Criteria in Solid Tumors, version 1.1.

104 women (median age, 64.0 years [range, 38-80 years]) with inadequate mismatch mutation repair endometrial malignancies were enrolled and treated with dostarlimab as of the data cutoff. 71 individuals were included in the study because they showed quantifiable illness at baseline and after 6 months or more of follow-up. There was a confirmed response in 30 patients (42.3% objective response rate; 95% CI, 30.6% -54.6%); 9 patients (12.7%) had a confirmed full response, and 21 patients (29.6%) had a confirmed partial response. Responses were long-lasting; nevertheless, the median length of reaction was not attained (median follow-up was 11.2 months). At 6 months, the projected chance of retaining a response was 96.4%, and at 12 months, it was 76.8%. The most prevalent grade 3 or higher treatment-related adverse events were anemia (3 of 104 [2.9%]), colitis (2 of 104 [1.9%]), and diarrhea (2 of 104 [1.9%]).