However, the observed impact of IDHi therapy on tumor response to ionizing radiation (IR) has been variable across murine models and engineered cell lines.<h4>Methods</h4>We investigated the effects of short-term (5 days) and long-term (≥5 weeks) exposure to the IDH1 inhibitor AGI-5198 on radiation-induced cytotoxicity. Here, IDH1 is linked to neoplasm.