FLT3 and acute myeloid leukemia: Notably, pretreatment of AML cell lines with the FLT3 inhibitor, quizartinib, for 16 h resulted in ~50% of the total cell population exhibiting a decrease in daunorubicin fluorescence, an indicator of drug uptake, suggesting that prolonged FLT3 inhibition may decrease CPX-351 uptake.