The U.S. Food and Drug Administration (FDA) approved the Promega OncoMate® MSI Dx Analysis System designed to identify patients with microsatellite high (MSI-H) solid tumors as a companion diagnostic designed for KEYTRUDA®, Merck’s anti-PD-1 therapy, the company announced today.

“This approval reflects our dedication to providing meaningful diagnostic advances, developed to the highest quality and regulatory standards,” Promega Global Clinical Market Director Alok Sharma said in a statement. “Our test connects patients with the therapy most likely to help them, working alongside our pharmaceutical collaborators and the clinicians who use the result.”

The biotech company received its first FDA approval for OncoMate in November 2025.

The approval applies to the United States and its territories.