Gilteritinib is a potent second generation inhibitor of both FLT3 and AXL, an oncogenic tyrosine kinase frequently overexpressed in AML and that facilitates FLT3 activation, a known mechanism of FLT3 tyrosine kinase inhibitor (TKI) resistance [79,80]. The gene discussed is FLT3; the disease is acute myeloid leukemia.