Business Wire·Oct 26, 2026, 11:35 AM ET

KEYTRUDA® (pembrolizumab) as Monotherapy Reduced the Risk of Disease Progression or Death by 43% for Certain Patients With Advanced or Recurrent Endometrial Cancer With Mismatch Repair Deficient (dMMR) Tumors Compared to Chemotherapy

MRK

KEYTRUDA monotherapy demonstrated a median progression-free survival (PFS) of 38.2 months compared to 8.4 months for platinum doublet chemotherapy in patients with dMMR advanced or recurrent endometrial cancer, representing a more than four-fold improvement.
The Phase 3 KEYNOTE-C93 trial showed a 43% reduction in the risk of disease progression or death for KEYTRUDA versus chemotherapy (HR=0.57; p=0.0002).
KEYNOTE-C93 is the first Phase 3 trial of a PD-1 inhibitor to show a statistically significant and clinically meaningful PFS improvement as monotherapy compared to chemotherapy in this patient population.
A favorable trend in overall survival (OS) was observed for KEYTRUDA with a hazard ratio of 0.77, though the difference was not statistically significant at this analysis (p=0.1000).
The confirmed objective response rate (ORR) was 64.1% for KEYTRUDA versus 62.1% for chemotherapy, with a median duration of response not reached for KEYTRUDA compared to 10.2 months for chemotherapy.
Grade ≥3 treatment-related adverse events occurred in 18.1% of patients receiving KEYTRUDA versus 50.7% of patients receiving chemotherapy, indicating a more favorable safety profile for the immunotherapy.
Late-breaking results from the trial were presented at the European Society for Medical Oncology (ESMO) Congress 2026 and published simultaneously in The Lancet.
The trial enrolled 299 patients randomized to receive KEYTRUDA every six weeks or carboplatin plus paclitaxel every three weeks, with results supporting a chemotherapy-free approach for dMMR patients.