Xospata Approved to Treat Acute Myeloid Leukemia

November 28, 2018 – The U.S. FDA has approved Xospata® (gilteritinib), manufactured by Astellas Pharma, to treat adult patients who have relapsed or refractory acute myeloid leukemia (AML) with an FLT3 mutation detected by an FDA-approved test. Invivoscribe Technologies’ LeukoStrat CDx FLT3 Mutation Assay has been approved for this purpose.

In 2018, an estimated 19,250 individuals in the U.S. were expected to be diagnosed with AML, a type of blood cancer that progresses rapidly and crowds out healthy blood cells. Approximately 10,670 patients were expected to die from the disease in the same year. The FLT3 gene mutation occurs in 25-30% of AML patients, and has been tied to particularly aggressive manifestations of the disease with a high incidence of relapse.

Xospata is the first drug to receive FDA approval for use as a single agent in treating AML patients who test positive for the FLT3 mutation and have relapsed or not responded to initial treatment. In a clinical trial, 21% of patients treated with Xospata achieved complete remission (no evidence of disease and full recovery of blood counts) or complete remission with partial hematologic recovery (no evidence of disease and partial recovery of blood counts). The median duration of response was 4.6 months. Of the 106 patients who were dependent on red blood cell or platelet transfusions at the beginning of the study, 31% became transfusion-free for at least 56 days when treated with Xospata.

Recommended dosing is 120mg taken orally once per day. Xospata, which has already been launched, is available in 40mg tablets at a wholesale acquisition cost (WAC) of $22,500 for a 30-day course of treatment.