Merck received FDA approval for its anti-PD-1 therapy KEYTRUDA and its subcutaneous formulation KEYTRUDA QLEX, both in combination with paclitaxel, for adults with PD-L1-positive platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal carcinoma. This label expansion establishes KEYTRUDA as the first PD-1 inhibitor cleared for platinum-resistant ovarian cancer, following a review of clinical data demonstrating safety and efficacy in this hard-to-treat population.

Platinum-resistant ovarian cancer patients face recurrence once first-line therapies fail, with limited approved treatments and high unmet need. The PD-L1-positive subset represents a significant niche, and this approval unlocks access to immunotherapy for a segment estimated to represent a multi-billion-dollar annual market globally.

This new indication further diversifies Merck’s oncology portfolio, building on KEYTRUDA’s existing approvals across multiple tumor types. It strengthens Merck’s competitive position against other checkpoint inhibitors and supports ongoing efforts to drive immuno-oncology revenues growth through label expansions and formulation innovations.