IDH1 and acute myeloid leukemia: Ivosidenib, formerly AG120, is a selective small molecule inhibitor of IDH1. Ivosidenib 500 mg daily was approved by the FDA for the treatment of relapsed-refractory IDH1-mutated AML (as well frontline therapy of IDH1-mutated AML in patients unfit for intensive chemotherapy) based on the results of the Phase 1–2 clinical trial evaluating 179 patients.