Roche teams up with Merck to develop new companion test for Keytruda

Roche will collaborate with Merck to develop a new companion diagnostic test to identify appropriate patients for anti-PD-1 therapy, this is, Keytruda (pembrolizumab). Specifically, the immunohistochemistry test will assess mismatch repair deficiency (MMR) in solid tumors via the detection of four MMR proteins.

MMR describes rapidly mutating cancer cells.