AKN-028 TFA, a novel tyrosine kinase (TK) inhibitor, is a potent, orally active FMS-like receptor tyrosine kinase 3 ( FLT3 ) inhibitor with an IC 50 value of 6?nM. AKN-028 TFA inhibits FLT3 autophosphorylation. AKN-028 TFA induces dose-dependent cytotoxic response (mean IC 50 =1?μM). AKN-028 TFA induces apoptosis by activation of caspase 3. AKN-028 TFA can be used in research of acute myeloid leukemia (AML).