Ivosidenib Now FDA-Approved as First-Line Treatment for AML with IDH1 Mutation

On May 2, 2019, the US Food and Drug Administration (FDA) approved ivosidenib (Tibsovo; Agios Pharmaceuticals, Inc) for the treatment of newly diagnosed acute myeloid leukemia (AML) with a susceptible IDH1 mutation, as detected by an FDA-approved companion diagnostic test, in patients who are aged ≥75 years or who have comorbidities that preclude the use of intensive induction chemotherapy.

This is the second FDA approval for ivosidenib, which was previously approved on July 20, 2018, for the treatment of patients with relapsed or refractory AML with a susceptible IDH1 mutation.

The most recent approval of this agent was based on results from the open-label, single-arm, multicenter, clinical trial that included 28 patients with newly diagnosed AML with an IDH1 mutation.

Patients were treated with ivosidenib, which was administered orally at a dose of 500 mg daily until disease progression, development of unacceptable toxicity, or stem-cell transplantation. The primary end point of the trial was the combined complete remission (CR) and complete remission with partial hematologic improvement (CRh) rate.

Twelve (42.9%) of the 28 patients achieved CR+CRh, and 7 (41.2%) of the 17 transfusion-dependent patients achieved transfusion independence lasting ≥8 weeks. Two of the 28 patients underwent stem-cell transplantation following ivosidenib treatment.

Adverse reactions occurring in ≥25% of patients included diarrhea, fatigue, edema, decreased appetite, leukocytosis, nausea, arthralgia, abdominal pain, dyspnea, differentiation syndrome, and myalgia.

The prescribing information for ivosidenib includes a boxed warning that differentiation syndrome may occur and can be fatal if not treated.