The US Food and Drug Administration (FDA) has granted priority review to gilteritinib for the treatment of adult patients with relapsed or refractory (R/R) acute myeloid leukemia (AML) who have a FLT3 mutation.
At present, no FLT3-targeting agents are approved for the treatment of R/R FLT3-mutation-positive AML, according to Astellas, the developer of the drug.
The FDA previously granted gilteritinib orphan drug designation and fast track designation.
The European Commission (EC) also granted gilteritinib orphan designation and the Japan Ministry of Health, Labor and Welfare (MHLW) did likewise.
Gilteritinib has demonstrated inhibitory activity against FLT3 internal tandem duplication (ITD) and FLT tyrosine kinase domain (TKD) mutation. These 2 FLT3 mutations are present in approximately 1/3 of AML patients.
The priority review for the new drug application is based on the ongoing phase 3 ADMIRAL trial.
The FDA aims to take action on a priority review application within 6 months of receiving it, rather than the standard 10 months.
The agency grants priority review to applications for products that may provide significant improvements in the treatment, diagnosis, or prevention of serious conditions.
The goal date for a decision by the FDA is the end of November.
This open-label multicenter randomized study compares gilteritinib with salvage chemotherapy in adult patients with FLT3 mutations who are refractory to or have relapsed after first-line AML therapy.
The study has enrolled 371 patients with FLT3 mutations present in bone marrow or whole blood, as determined by a central lab.
Patients were randomized in a 2:1 ratio to receive gilteritinib (120 mg) or salvage chemotherapy.
Salvage chemotherapy could consist of low-dose cytarabine, azacitidine, MEC (mitoxantrone, etoposide, cytarabine) induction chemotherapy, or FLAG-IDA (fludarabine, cytarabine, and granulocyte colony-stimulating factor [G-CSF] with idarubicin) induction chemotherapy.
The primary endpoints of the study are overall survival and complete remission or complete remission with partial hematologic recovery.
Secondary endpoints include event-free survival, complete remission rate, leukemia-free survival, duration of remission, transplantation rate, fatigue inventory, among other outcomes.
The study is estimated to be completed in October for its primary endpoint and February 2020 for the entire study.