The leading pharmaceutical company Merck & Co., Inc. announced on Thursday that its Phase 3 KEYNOTE-B21 trial, assessing the effectiveness of its anti-PD-1 therapy KEYTRUDA (pembrolizumab) combined with chemotherapy, did not meet its primary objective of disease-free survival (DFS) in patients newly diagnosed with high-risk endometrial cancer after undergoing curative surgery.
The KEYNOTE-B21 trial, also known as ENGOT-en11/GOG-3053, was a randomized, double-blind Phase 3 trial sponsored by Merck, with approximately 1,095 patients participating. The results of the trial were presented at a pre-specified interim analysis conducted by an independent Data Monitoring Committee.
Merck noted that the combination of KEYTRUDA and chemotherapy failed to meet the pre-established statistical criteria for DFS in comparison to a placebo, plus the same therapeutic regimen. Another primary objective of the trial, overall survival (OS), was not formally tested since DFS did not show superiority.
The safety profile of KEYTRUDA was in line with that observed in earlier studies, and no new safety issues were identified.
Merck intends to carry out a comprehensive evaluation of the data from the study and plans to work alongside investigators to share the findings with the scientific community. In the United States, the use of KEYTRUDA is approved for two indications in endometrial cancer.
Gursel Aktan, Vice President of Global Clinical Development at Merck Research Laboratories, expressed disappointment at the results but emphasized their commitment to expanding the established role of KEYTRUDA in advanced endometrial carcinoma. According to Aktan, they plan to expedite clinical research in evaluating KEYTRUDA-based combinations and other experimental candidates, inclusive of antibody-drug conjugates, in endometrial and other gynecological cancers.
