Keytruda boosts PFS in OC

Merck, known as MSD outside of the United States and Canada, announced that the Phase III KEYNOTE-B96 trial, also known as ENGOT-ov65, met its primary endpoint of progression-free survival (PFS) for the treatment of patients with platinum-resistant recurrent ovarian cancer whose tumors expressed PD-L1 and in all comers. The study also met a secondary endpoint of overall survival (OS) in patients whose tumors express PD-L1. The study is evaluating Keytruda (pembrolizumab), Merck’s anti-PD-1 therapy, in combination with chemotherapy (paclitaxel) with or without bevacizumab for these patients. The trial is continuing and OS for the full study population will be evaluated at a future analysis.

At pre-specified interim analyses conducted by an independent Data Monitoring Committee, the Keytruda-based regimen demonstrated a statistically significant and clinically meaningful improvement in PFS regardless of PD-L1 status compared to placebo plus chemotherapy with or without bevacizumab. The study also showed a statistically significant and clinically meaningful improvement in OS in patients whose tumors express PD-L1 (Combined Positive Score [CPS] ≥1) compared to placebo plus chemotherapy with or without bevacizumab. The safety profile of Keytruda in this trial was consistent with that observed in previously reported studies; no new safety signals were identified. Results will be presented at an upcoming medical meeting and shared with regulatory authorities worldwide.

“This marks the first time a Keytruda-based regimen has shown the ability to help certain patients with platinum-resistant ovarian cancer live longer, and the first time an immune checkpoint inhibitor-based regimen has demonstrated an overall survival benefit in ovarian cancer,” said Dr. Gursel Aktan, vice president, global clinical development, Merck Research Laboratories. “The positive results from this trial add to the growing body of evidence supporting the potential benefit of Keytruda across gynecological cancers, including this difficult-to-treat form of ovarian cancer for which patients are in need of new options.”

Keytruda is not approved to treat ovarian cancer. 

KEYNOTE-B96, also known as ENGOT-ov65, is a randomized, double-blind Phase III trial (ClinicalTrials.gov, NCT05116189) sponsored by Merck and conducted in collaboration with the European Network for Gynecologic Oncology Trial (ENGOT) groups investigating Keytruda 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, and OS is a key secondary endpoint. The trial enrolled an estimated 643 patients who were randomized to receive:i) Keytruda (400 mg intravenously every six weeks for approximately two years) plus paclitaxel with or without bevacizumab, or; ii) placebo plus paclitaxel with or without bevacizumab.