Experience with FLT3 Inhibitor Midostaurin in Newly Diagnosed Acute Myeloid Leukemia Patients

Abstract

Introduction With the introduction of FLT3 inhibitors in recent years, the presence of FLT3 mutation in newly diagnosed acute myeloid leukemia (AML) patients has become more important. it was observed that the addition of Midostaurin to remission induction and consolidation chemotherapy, brought a 22% reduction in mortality risk in patients with FLT3 mutation. In the light of the above information, we aimed to share our experience regarding the use of Midostaurin in our newly diagnosed AML patients. Methods The data of 20 patients who were diagnosed with AML between April 2020 and November 2020 in the Hematology Department of Bursa City Hospital and who were eligible for standard remission induction therapy were evaluated retrospectively. Standard remission induction chemotherapy consisting of a combination of cytosine arabinoside (ARA-C) and an anthracycline was applied to patients. Consolidation treatment with high dose ARA-C was given to patients in remission; Midosaturin 100 mg was added to High-dose ARA-C between days 8 and 21 in patients with FLT3 mutation. Results: Twenty patients included in the study, 14 were men and 6 were women. There were six patients with the FLT3 mutation. Five patients with FLT3 mutation were male and one was female. The mean age of the patients is 53.8; the mean age of the patients with FLT 3 mutation was 49.8 years. Two patients with FLT 3 mutation died due to sepsis during remission induction treatment; In Four patients, complete response was obtained with remission induction therapy. Four patients had been given midostaurin with high dose ARA-C and referred for bone marrow transplantation. Conclusion The use of FLT3 inhibitors in combination with chemotherapeutic agents in the treatment of AML patients with FLT3 mutation is considered as a standard. However, it takes a certain amount of time for the FLT3 mutation to result. For this reason, Midostaurin treatment could be added not during remission induction but consolidation. Although our study included a limited number of patients it shows the importance of Midostaurin treatment in newly diagnosed AML patients with FLT3 mutation as real-world data.

Keywords

• AML
• FLT3 mutation
• Midostaurin

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