Posted: Monday, June 21, 2021
The updated analyses of an ongoing, multicenter, open-label, phase Ib trial revealed that patients with heavily pretreated and prior tyrosine kinase inhibitor–exposed relapsed or refractory FLT3-mutated acute myeloid leukemia (AML) achieved high rates of modified composite complete remission, with “encouraging” molecular clearance rates after treatment with the BCL-2 inhibitor venetoclax plus the FLT3 inhibitor gilteritinib. These findings, which Jessica K. Altman, MD, of Northwestern University, Chicago, and colleagues presented during the European Hematology Association Virtual Congress (EHA2021; Abstract S135), highlighted the antileukemic activity of this combination.
A total of 43 patients with FLT3-mutated relapsed or refractory AML were administered doses of up to 400 mg of venetoclax plus 80 or 120 mg of gilteritinib daily. Most patients (98%) experienced grade 3 or 4 adverse events. Cytopenias of grade 3 or higher were reported in 79% of patients. Pneumonia (21%) was the most frequently reported grade 3 or 4 nonhematologic adverse event. There was one case of clinical tumor-lysis syndrome. A total of 74% of patients experienced serious adverse events. The mortality rates were 0% and 12% at 30 and 60 days, respectively.
In the FLT3-mutated efficacy population, 86% achieved a modified composite complete remission, with a median time to first response of 1 month. A modified composite complete remission was also achieved by 86% of patients with prior FLT3 tyrosine kinase inhibitor exposure. FLT3 molecular clearance was reported in 69% of patients with a modified composite complete remission who had polymerase chain reaction conducted at baseline and at least one follow-up timepoint. The median durations of response and overall survival were 5.6 and 10.5 months, respectively, in both the internal tandem duplication cohort and in all FLT3-mutated patients. The median duration of overall survival was 10.5 months with prior tyrosine kinase inhibitor use and 10.6 months without it.
Disclosure: For full disclosures of the study authors, visit library.ehaweb.org.