ETX-880

ETX-880 is a small-molecule inhibitor of Werner syndrome helicase (WRN) developed by ENSEM Therapeutics. It is specifically designed to target cancers with microsatellite instability-high (MSI-H) status, such as colorectal, gastric, and endometrial cancers. WRN helicase is a member of the RecQ helicase family and has been identified as a critical synthetic lethal target in MSI-H cells, which lack functional DNA mismatch repair (MMR) systems. By inhibiting WRN, ETX-880 induces extensive DNA damage and cell death in MSI-H tumor cells while sparing normal cells, providing a potential precision medicine approach for patients with MMR-deficient malignancies.