Merck’s phase 3 KEYNOTE-811 trial of Keytruda in combo with trastuzumab and fluoropyrimidine- and platinum-containing chemotherapy meets dual primary endpoint of OS in patients with HER2-positive ad

Merck, known as MSD outside the US and Canada, announced that its phase 3 trial KEYNOTE-811 evaluating Keytruda (pembrolizumab) with trastuzumab and chemotherapy met its primary endpoint of overall survival (OS) in first-line treatment for HER2-positive gastric or GEJ adenocarcinoma.

Now FDA-approved under accelerated regulations, Keytruda combo is for adults with HER2-positive gastric or GEJ adenocarcinoma whose tumors express PD-L1 (CPS =1) as determined by an FDA-approved test. Continued approval depends on clinical benefit confirmation in the final analysis of KEYNOTE-811.

In the final analysis, Keytruda combo significantly improved OS over placebo in the intention-to-treat population, particularly in CPS =1 patients. The safety profile remained consistent.

Gastric cancer, often detected late, is the fifth most diagnosed and leading cause of cancer death globally. In the US, it's estimated there will be around 26,890 new cases and 10,880 deaths in 2024. Keytruda, an anti-PD-1 therapy, boosts the immune system to fight tumor cells.