There are three FTL3 inhibitors, midostaurin, gilteritinib, and quizartinib have been approved for clinical treatment of AML. The treatment with RF-1302 showed very little toxicity (only 2% body weight loss) which were well below the maximum tolerated dose. These preclinical results suggest that RF-1302 represents a novel dual inhibitor of PIM1 and FLT3, which may constitute a highly efficacious modality for the treatment of FLT3 mutant AML, and is worthy of further clinical evaluation.