The US Food and Drug Administration (FDA) has accepted Astellas Pharma’s new drug application (NDA) for gilteritinib and granted priority review for the product’s use in the treatment of acute myeloid leukaemia (AML).

Astellas is seeking approval for gilteritinib to treat relapsed or refractory AML patients having a FLT3 mutation identified by a FDA-approved test.

The drug candidate is said to inhibit FLT3 internal tandem duplication (ITD) and tyrosine kinase domain (TKD) mutations, along with the AXL receptor found in AML cell lines.

Gilteritinib is an investigational product discovered by the Astellas in alliance with Kotobuki Pharmaceutical.

“The FDA’s acceptance of this NDA, with priority review, represents a significant milestone for gilteritinib.”

Astellas Pharma Oncology Development senior vice-president and global therapeutic area head Steven Benner said: “FLT3 mutations impact approximately 30% of AML patients and are often associated with poor survival outcomes. Many with this condition relapse after treatment or don’t respond to currently available treatments.

“The FDA’s acceptance of this NDA, with priority review, represents a significant milestone for gilteritinib and Astellas in our mission to help AML patients and the physicians who treat them.”

Gilteritinib is being evaluated in Phase III clinical trials with different AML patient populations. The application submitted to the FDA includes data from the ongoing ADMIRAL trial.

The open-label, multi-centre, randomised Phase III trial has been designed to compare gilteritinib with salvage chemotherapy in 369 FLT3 mutation-positive AML patients who have relapsed or became refractory following first-line therapy.

Gilteritinib previously secured FDA fast track status and orphan drug designation in the US, Europe and Japan. It also obtained SAKIGAKE designation from Japan’s Ministry of Health, Labor and Welfare.

Astellas holds exclusive rights to develop, manufacture and potentially market the drug candidate.