Pembrolizumab Combination FDA-Approved for Ovarian Cancer

The FDA approved pembrolizumab (Keytruda; Merck) and pembrolizumab plus berahyaluronidase alfa-pmph (Keytruda Qlex; Merck) in combination with paclitaxel, with or without bevacizumab, for adult patients with platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal carcinoma whose tumors express PD-L1 (CPS ≥ 1). The decision was supported by data from the KEYNOTE-B96 trial (NCT05116189).

The approval also includes the companion diagnostic device PD-L1 IHC 22C3 pharmDx (Agilent Technologies, Inc).

Pembrolizumab Safety and Efficacy

The KEYNOTE-B96 phase 3, randomized, double-blind, multicenter, placebo-controlled study compared the safety and efficacy of pembrolizumab plus paclitaxel with or without bevacizumab to placebo plus paclitaxel with or without bevacizumab. The trial showed clinically significant improvements in progression-free survival (PFS) and overall survival (OS) in patients treated with the pembrolizumab combination.

The trial included 643 patients with platinum-resistant, epithelial ovarian, fallopian tube, or primary peritoneal carcinoma who received 1 or 2 prior lines of platinum-based chemotherapy for ovarian carcinoma and progressed within 6 months.

The patients were randomized 1:1 to 2 arms: pembrolizumab plus paclitaxel with or without bevacizumab, or placebo plus paclitaxel with or without bevacizumab. Patients in the pembrolizumab arm received pembrolizumab intravenously (IV) at a dosage of 400 mg for 18 6-week cycles (approximately 2 years) plus paclitaxel 80 mg/m² via IV infusion on days 1, 8, and 15 of each 3-week cycle until intolerance or disease progression. Bevacizumab was administered at 10 mg/kg via IV infusion of each 2-week cycle until intolerance, disease progression, or at the investigator's discretion. The placebo group received the same dosages of paclitaxel and bevacizumab.

In both arms, a severe hypersensitivity reaction to paclitaxel or an adverse event (AE) requiring discontinuation of paclitaxel warranted treatment with docetaxel (75 mg/m² every 3 weeks).

PFS, evaluated by investigators in accordance with RECIST version 1.1, served as the primary efficacy end point, with OS assessed as an additional measure of clinical benefit.

In the PD-L1–positive population (combined positive score [CPS] ≥ 1; n = 466), treatment with pembrolizumab resulted in a median PFS of 8.3 months (95% CI, 7.0–9.4), compared with 7.2 months (95% CI, 6.2–8.1) in patients receiving placebo (HR, 0.72; 95% CI, 0.58–0.89; P = .0014). Median OS also favored the pembrolizumab arm at 18.2 months (95% CI, 15.3–21.0) versus 14.0 months (95% CI, 12.5–16.1) with placebo (HR, 0.76; 95% CI, 0.61–0.94; P = .0053).

Safety findings from KEYNOTE-B96 showed that pembrolizumab administered with paclitaxel, with or without bevacizumab, demonstrated a tolerability profile consistent with previous studies, and no unexpected adverse events were reported.

Pembrolizumab Dosing and Toxicities

Pembrolizumab is administered at a recommended dose of 200 mg every 3 weeks or 400 mg every 6 weeks until disease progression, unacceptable toxicity, or for up to 24 months. When used in combination with berahyaluronidase, the recommended dose is 395 mg/4800 units every 3 weeks or 790 mg/9600 units every 6 weeks, continued until disease progression, unacceptable toxicity, or for up to 24 months. When administered on the same day, pembrolizumab or pembrolizumab with berahyaluronidase should be given prior to paclitaxel, with or without bevacizumab.

Prescribing information for pembrolizumab warnings for immune-mediated adverse reactions, infusion-related reactions, complications of allogeneic hematopoietic stem cell transplantation, and embryo-fetal toxicity.

REFERENCES

1. Pembrolizumab/​placebo plus paclitaxel with or without bevacizumab for platinum-resistant recurrent ovarian cancer (MK-3475-B96/​KEYNOTE-B96/​ENGOT-ov65). Clinicaltrials.gov. Updated July 14, 2025. Accessed February 10, 2026. https://clinicaltrials.gov/study/NCT05116189

2. FDA approves pembrolizumab with paclitaxel for platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal carcinoma. FDA. February 10, 2026. Accessed February 10, 2026. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-pembrolizumab-paclitaxel-platinum-resistant-epithelial-ovarian-fallopian-tube-or?utm_medium=email&utm_source=govdelivery