Merck’s KEYTRUDA Combination Shows Promising Results in Phase 3 KEYNOTE-B96 Trial for Ovarian Cancer

Merck (NYSE: MRK), operating as MSD outside the United States and Canada, has reported positive results from its Phase 3 KEYNOTE-B96 trial (ENGOT-ov65), which demonstrated significant benefits for patients with platinum-resistant recurrent ovarian cancer. The trial met its primary endpoint of progression-free survival (PFS) across all patients, irrespective of PD-L1 status, and achieved a secondary endpoint of overall survival (OS) among patients whose tumors express PD-L1.

The study assessed the efficacy of Merck’s anti-PD-1 therapy, KEYTRUDA® (pembrolizumab), in combination with chemotherapy (paclitaxel) with or without bevacizumab. This breakthrough provides new hope for patients facing a highly challenging form of ovarian cancer. Further evaluation of overall survival in the full study population is ongoing.

Independent analysis by the Data Monitoring Committee confirmed that the KEYTRUDA-based regimen significantly improved PFS for all patients and demonstrated a marked OS benefit among those with PD-L1-positive tumors (Combined Positive Score [CPS] ≥1). The safety profile of KEYTRUDA in this trial was consistent with prior studies, with no new safety issues identified.

“This marks a major advancement for patients with platinum-resistant ovarian cancer, as it is the first time a KEYTRUDA-based regimen has demonstrated the potential to extend survival,” stated Dr. Gursel Aktan, Vice President of Global Clinical Development at Merck Research Laboratories. “These findings further validate the role of KEYTRUDA in gynecological cancers.”

Although KEYTRUDA is not currently approved for treating ovarian cancer, the positive outcomes from KEYNOTE-B96 highlight its potential. Beyond this trial, Merck’s partnership with AstraZeneca has led to three U.S. approvals for LYNPARZA® (olaparib) in treating ovarian cancer.

Looking ahead, Merck has also initiated the Phase 2/3 REJOICE-Ovarian01 trial, exploring raludotatug deruxtecan (R-DXd), an innovative CDH6-directed DXd antibody-drug conjugate, for platinum-resistant ovarian cancer.

The full findings from the KEYNOTE-B96 trial will be presented at an upcoming medical meeting and submitted to regulatory authorities worldwide, underscoring Merck’s commitment to advancing treatments for complex ovarian cancers.