The FDA has granted approval for the first oral, targeted therapy for relapsed/ refractory acute myeloid leukemia (R/R AML) adults patients and an IDH1 mutation as detected by an FDA approved test. The approval of TIBSOVO® (ivosidenib) is based on Phase I study results.
R/R AML has a poor prognosis. The 5-year survival rate is approximately 27%. For 6–10%of AML patients, the mutated IDH1 enzyme blocks normal blood stem cell differentiation, contributing to the genesis of AML.
This FDA approval was based on the clinical data from an open-label, single-arm, multicenter dose-escalation and expansion trial of adult patients with R/R AML and an IDH1 mutation. TIBSOVO was approved concurrently with the Abbott RealTime™ IDH1 companion diagnostic test for selection of patients with R/R AML for treatment with TIBSOVO.
The efficacy of TIBSOVO was studied in a single-arm trial of 174 adult patients with relapsed or refractory AML with an IDH1 mutation. The trial measured the percentage of patients with no evidence of disease and full recovery of blood counts after treatment (complete remission or CR), as well as patients with no evidence of disease and partial recovery of blood counts after treatment (complete remission with partial hematologic recovery or CRh). With a median follow-up of 8.3 months, 32.8% of patients experienced a CR orCRh that lasted a median 8.2 months. Of the 110 patients who required transfusions of blood or platelets due to AML at the start of the study, 37% went at least 56 days without requiring a transfusion after treatment with Tibsovo.
“AML patients who relapse or are refractory to available therapies have few, if any, treatment options,” explained Hagop Kantarjian, The University of Texas MD Anderson Cancer Center (TX, USA). “The clinical study demonstrated that TIBSOVO has the potential to deliver strong, durable responses as a single agent and can help patients achieve and maintain transfusion independence. IDH inhibitors represent a new class of noncytotoxic, targeted therapies for AML patients with IDH mutations.”
Richard Pazdur (FDA’s Center for Drug Evaluation and Research) concluded: “The use of TIBSOVO is associated with a complete remission in some patients and a reduction in the need for both red cell and platelet transfusions.”