In CBF AML, which is frequently dependent upon KIT-mediated (gain-of-function) signal transduction, quizartinib demonstrated varying antiproliferative and cytotoxic efficacy in in vitro and ex vivo leukemia cells – in some cases within the low nanomolar range of FLT3 ITD (JM) positive samples. This evidence concerns the gene FLT3 and leukemia.