ISM0003091

**ISM0003091** is a preclinical-to-early clinical **orally bioavailable small-molecule inhibitor of ubiquitin specific peptidase 1** being developed originally by **Insilico Medicine** for cancer and later advanced clinically by **Exelixis** as **XL309**. The program has been described as a selective **USP1 inhibitor** with potential antineoplastic activity; by inhibiting USP1-mediated deubiquitination, it is intended to disrupt DNA damage response and replication fork protection pathways, leading to impaired tumor-cell survival and possible sensitization to DNA-damage-based therapies such as PARP inhibition. Public sources indicate that the compound was generated using Insilico's AI-enabled drug discovery platform, received U.S. IND clearance, and entered a first-in-human phase 1 study in advanced solid tumors, including evaluation both as monotherapy and in combination with olaparib.

Other names

USP1 inhibitor ISM3091USP-1 inhibitor ISM3091USP 1 inhibitor ISM3091