In patients receiving an FLT3 TKI-based therapy for the first time in an R/R AML setting, the CRc rates and median OS were 45%, 21%, and 10%, and 7.9 months, 4.0 months, and 4.1 months with the first (n = 183), second (n = 89), and third/fourth (n = 29) FLT3i-based therapy, respectively. This evidence concerns the gene FLT3 and acute myeloid leukemia.