MSI

A phase 1 clinical trial is testing a Werner helicase inhibitor in patients with advanced microsatellite instability (MSI) solid tumors. The early-stage study, published in Nature, evaluates safety, dosing and early anti-tumor activity of the investigational drug. Werner helicase is a DNA repair protein, and blocking it is a new synthetic-lethality approach for cancers that have already resisted standard treatments, including immunotherapy.