The European Commission has approved pembrolizumab plus paclitaxel plus or minus bevacizumab for the treatment of adults with PD-L1 (CPS ≥1) platinum-resistant recurrent ovarian carcinoma who have received one or two prior systemic treatment regimens.

• The pembrolizumab regimen is the first and only PD-1 inhibitor-based treatment approved in the European Union for these patients
• The approval was supported by data from the Phase 3 KEYNOTE-B96 trial in which the pembrolizumab regimen demonstrated a statistically significant improvement in progression-free and overall survival compared to placebo plus paclitaxel, with or without bevacizumab

Merck, known as MSD outside of the United States and Canada, has announced that 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 tumours 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 subcutaneous pembrolizumab (also known as Keytruda QLEXTM (pembrolizumab and berahyaluronidase alfa-pmph) in the U.S.], makes this regimen the first and only PD-1 inhibitor-basd treatment option for eligible patients with platinum-resistant ovarian cancer in the EU.

“Despite recent advances, patients with ovarian cancer face a significant unmet need when their disease progresses and becomes resistant to standard platinum-based therapy,” said Dr. Nicoletta Colombo, director of the Gynaecologic Oncology Programme at the European Institute of Oncology in Milan, Italy.

“The approval of this pembrolizumab-based regimen is an important advance that provides a crucial new treatment option and represents a welcome addition to the treatment landscape for appropriate patients with PD-L1-positive platinum-resistant ovarian cancer across Europe.”

This approval is based on results from the Phase 3 KEYNOTE-B96 trial (also known as ENGOT-ov65), in which pembrolizumab 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 tumours 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, pembrolizumab 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 tumours expressed PD-L1 (CPS ≥1) when compared to placebo plus paclitaxel, with or without bevacizumab.

For patients with platinum-resistant recurrent ovarian cancer whose tumours expressed PD-L1 (CPS ≥1) who received the pembrolizumab-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 pembrolizumab-based regimen also demonstrated a statistically significant and clinically meaningful improvement in OS for patients with platinum-resistant recurrent ovarian cancer whose tumours 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 tumours expressed PD-L1 (CPS ≥1) who received the pembrolizumab-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 authorises marketing of this pembrolizumab (Keytruda) treatment regimen for this indication in all 27 EU member states, as well as Iceland, Liechtenstein and Norway. Timing for commercial availability of pembrolizumab for this indication in individual EU countries will depend on multiple factors, including the completion of national reimbursement procedures.

In February 2026, pembrolizumab 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 tumours express PD-L1 (CPS ≥1), as determined by an FDA-authorized test, and who have received one or two prior systemic treatment regimens.

About KEYNOTE-B96/ENGOT-ov65

KEYNOTE-B96, also known as ENGOT-ov65, is a multicenter, randomised, double-blind placebo-controlled Phase 3 trial (ClinicalTrials.gov, NCT05116189) sponsored by Merck and conducted in collaboration with the European Network for Gynecologic Oncology Trial (ENGOT) groups investigating pembrolizumab, Merck’s anti-PD-1 therapy, in combination with chemotherapy (paclitaxel), with or without bevacizumab, compared to placebo plus chemotherapy with or without bevacizumab for the treatment of platinum-resistant recurrent ovarian cancer. The primary endpoint is PFS, as assessed by investigator according to Response Evaluation Criteria in Solid Tumours version 1.1 (RECIST v1.1), and OS is a key secondary endpoint. The trial enroled 643 patients with epithelial ovarian, fallopian tube or primary peritoneal carcinoma, regardless of PD-L1 tumour expression status, who received one or two prior lines of systemic therapy for ovarian carcinoma, including at least one line of platinum-based chemotherapy. Of the 643 enroled patients, 72% of patients had tumours expressing PD-L1 (CPS ≥1). Patients were enroled in KEYNOTE-B96 regardless of PD-L1 tumou expression status. Patients were randomised (1:1) to receive either pembrolizumab plus paclitaxel, with or without bevacizumab, or placebo plus paclitaxel, with or without bevacizumab. Pembrolizumab (400 mg) or placebo were administered on Day 1 of each six-week treatment cycle and paclitaxel (80 mg/m2) was administered on Days 1, 8 and 15 of each three-week treatment cycle. The option to use bevacizumab was by investigator choice prior to randomisation. Bevacizumab (10 mg/kg) was administered on Day 1 of a two-week treatment cycle.

Results from the final analysis of the KEYNOTE-B96 trial evaluating pembrolizumab plus paclitaxel, with or without bevacizumab, including PFS and OS results for patients with platinum-resistant recurrent ovarian cancer regardless of PD-L1 status, were recently presented at the European Society of Gynaecological Oncology (ESGO) 2026 Congress.

Source: Merck