Dr. Mark Levis Discusses Quizartinib in AML

Mark J. Levis, MD, PhD, Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, discusses the design and results of a phase II trial of quizartinib in patients with FLT3-ITD positive or negative relapsed/refractory acute myeloid leukemia (AML).

Quizartinib is directed against FLT3, an enzyme which leads to a poor prognosis in patients with AML. Cohort 2 (137 patients) of the study constituted the basis for the analysis and included patients ≥ 18 years old with AML relapsed or refractory to 2nd-line, salvage chemotherapy or relapsed after hematopoietic stem cell transplantation. FLT3-ITD(+) patients had a median age of 50 years and FLT3-ITD(-) patients had a median age of 55 years. Patients were treated continuously with quizartinib during 28-day cycles at doses of 90 mg/day for females and 135 mg/day for males.

The study confirmed the high degree of activity of quizartinib monotherapy in FLT3 ITD(+) and FLT3-ITD(-) AML patients relapsed/refractory to 2nd-line treatment or hematopoietic stem cell transplantation.

The composite complete remission rate included complete remission, complete remission with incomplete platelet recovery, and complete remission with incomplete hematologic recovery. In the FLT3-ITD(+) arm, the composite complete remission rate was 44%, with a median duration of response of 11.3 weeks and median overall survival of 23.1 weeks. In the FLT3-ITD(-) arm, the composite complete remission rate was 34%, with a median duration of response of 5.0 weeks and median overall survival of 25.6 weeks.