The KEYTRUDA regimen is the first and only PD-1 inhibitor-based treatment approved in the European Union for these patients

Approval supported by data from the Phase 3 KEYNOTE-B96 trial in which the KEYTRUDA regimen demonstrated a statistically significant improvement in progression-free and overall survival compared to placebo plus paclitaxel, with or without bevacizumab

Merck (NYSE:MRK), known as MSD outside of the United States and Canada, announced that KEYTRUDA® (pembrolizumab), in combination with paclitaxel, with or without bevacizumab, is approved in the European Union (EU) for the treatment of platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal carcinoma in adults whose tumors express PD-L1 with a Combined Positive Score (CPS) ≥1 and who have received one or two prior systemic treatment regimens. This approval, which also covers KEYTRUDA SC® [known as KEYTRUDA QLEXTM (pembrolizumab and berahyaluronidase alfa-pmph) in the U.S.], makes this regimen the first and only PD-1 inhibitor-based treatment option for eligible patients with platinum-resistant ovarian cancer in the EU.

This approval is based on results from the Phase 3 KEYNOTE-B96 trial (also known as ENGOT-ov65), in which KEYTRUDA plus paclitaxel, with or without bevacizumab, demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS), the trial's primary endpoint, and overall survival (OS), a key secondary endpoint, for patients with platinum-resistant recurrent ovarian cancer whose tumors expressed PD-L1 (CPS ≥1) compared to placebo plus paclitaxel, with or without bevacizumab. The approval follows a positive recommendation from the European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP), received in February 2026.

In the KEYNOTE-B96 trial, KEYTRUDA plus paclitaxel, with or without bevacizumab, demonstrated a statistically significant and clinically meaningful improvement in PFS, reducing the risk of disease progression or death by 28% (HR=0.72 [95% CI, 0.58-0.89]; p=0.0014) in patients with platinum-resistant recurrent ovarian cancer whose tumors expressed PD-L1 (CPS ≥1) when compared to placebo plus paclitaxel, with or without bevacizumab. For patients with platinum-resistant recurrent ovarian cancer whose tumors expressed PD-L1 (CPS ≥1) who received the KEYTRUDA-based regimen, median PFS was 8.3 months (95% CI, 7.0-9.4) versus 7.2 months (95% CI, 6.2-8.1) for patients receiving the placebo regimen.

The KEYTRUDA-based regimen also demonstrated a statistically significant and clinically meaningful improvement in OS for patients with platinum-resistant recurrent ovarian cancer whose tumors expressed PD-L1 (CPS ≥1), reducing the risk of death by 24% (HR=0.76 [95% CI, 0.61-0.94]; p=0.0053) compared to placebo plus paclitaxel with or without bevacizumab. For patients with platinum-resistant recurrent ovarian cancer whose tumors expressed PD-L1 (CPS ≥1) who received the KEYTRUDA-based regimen, median OS was 18.2 months (95% CI, 15.3-21.0) versus 14.0 months (95% CI, 12.5-16.1) for patients receiving the placebo regimen.

This approval authorizes marketing of this KEYTRUDA treatment regimen for this indication in all 27 EU member states, as well as Iceland, Liechtenstein and Norway. Timing for commercial availability of KEYTRUDA for this indication in individual EU countries will depend on multiple factors, including the completion of national reimbursement procedures.

In February 2026, KEYTRUDA plus paclitaxel, with or without bevacizumab, was approved by the U.S. Food and Drug Administration(FDA) to treat adult patients with platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal carcinoma whose tumors express PD-L1 (CPS ≥1), as determined by an FDA-authorized test, and who have received one or two prior systemic treatment regimens.