An orally bioavailable inhibitor of the fibroblast growth factor receptor (FGFR) and FMS-like tyrosine kinase 3 (FLT3; CD135; STK1; FLK2), with potential antineoplastic activity. Upon oral administration of FLT3/FGFR dual kinase inhibitor MAX-40279, this agent binds to and inhibits both FGFR and FLT3, including FLT3 mutant forms, which results in the inhibition of FGFR/FLT3-mediated signal transduction pathways. This inhibits proliferation in FGFR/FLT3-overexpressing tumor cells. FGFR, a family of receptor tyrosine kinases, is upregulated in many tumor cell types. FLT3, a class III receptor tyrosine kinase (RTK), is overexpressed or mutated in most B-lineage neoplasms and in acute myeloid leukemias. They both play key roles in cellular proliferation and survival.