Olutasidenib is a novel mutant isocitrate dehydrogenase 1 (mIDH1) inhibitor under consideration with the FDA for the potential treatment of mIDH1+ Relapsed or Refractory Acute Myeloid Leukemia (R/R AML).

*Olutasidenib is not FDA-approved for this indication.

Acute myeloid leukemia (AML)

AML is a cancer that starts in a person’s bone marrow but often quickly moves into the blood. AML develops from immature blood cells, known as myeloid cells, that are supposed to mature into white blood cells. However, the diseased myeloid cells do not function properly. They instead multiply rapidly, which causes normal blood cell production to fail. AML occurs primarily in adults and accounts for about 1 percent of all adult cancers. The American Cancer Society estimates that in the United States, there will be about 20,050 new cases in 2022, mostly in adults.1

Relapsed AML affects about half of all patients who, following treatment and remission, experience a return of leukemia cells in the bone marrow.2 Refractory AML, which affects between 10 and 40 percent of newly diagnosed patients, occurs when a patient fails to achieve remission even after intensive treatment.3 Quality of life declines for patients with each successive line of treatment for AML, and well-tolerated treatments in relapsed or refractory disease remain an unmet need. 

Olutasidenib is an oral, small molecule investigational agent designed to selectively bind to and inhibit mutated IDH1 enzymes. This targeted agent has the potential to provide therapeutic benefit by reducing 2-HG levels and restoring normal cellular differentiation. IDH1 is a natural enzyme that is part of the normal metabolism of all cells. When mutated, IDH1 activity can promote blood malignancies and solid tumors. IDH1 mutations are present in 6 to 16 percent of patients with AML.4

Development of olutasidenib:

  • The U.S. Food and Drug Administration (FDA) has accepted Forma’s New Drug Application (NDA) for olutasidenib, which was filed by Rigel's partner, Forma Therapeutics. The Prescription Drug User Fee Act (PDUFA) target action date is February 15, 2023.
  • Olutasidenib was evaluated in a Phase 1/2 study to evaluate the safety, efficacy and pharmacokinetics/pharmacodynamics (PK/PD) of olutasidenib for patients with AML or myelodysplastic syndrome (MDS) with an IDH1 mutation. The primary endpoint of the Phase 2 pivotal study is a complete remission (CR) plus a complete remission with partial hematological recovery (CRh) that is defined as <5% blasts in the bone marrow, no evidence of disease and partial recovery of peripheral blood counts (platelets >50,000/microliter and ANC >500/microliter). (NCT02719574)


  1. The American Cancer Society. Key Statistics for Acute Myeloid Leukemia (AML). Revised January 12, 2022. Accessed Aug. 1, 2022 at
  2. Leukaemia Care. (2019). Relapse in Acute Myeloid Leukaemia (AML). Version 3. Reviewed October 2021. Accessed Dec 2, 2021 at
  3. Thol F, Schlenk RF, Heuser M, Ganser A. How I treat refractory and early relapsed acute myeloid leukemia. Blood. 2015 Jul 16;126(3):319-27. doi:
  4. DiNadro C, et al. Characteristics, clinical outcome, and prognostic significance of IDH mutations in AML. Am J Hematol 2015 Aug;90(8):732-6. doi: