Biochem/physiol Actions

AST487 is aN,N′-diphenyl urea, which inhibits growth and calcitonin gene expression in medullary thyroid cancer cells.

AST487 is an orally available type II tyrosine kinase inhibitor (TKI) that exhibits potent antiproliferation activity against FLT3, RET, PDGFR1, but not BRAF, oncogenic fusions/mutations-driven growth (IC50 = 1.8 nM/FLT3-ITD BaF3, 5.1 nM/FLT3 D835I BaF3, 9-27 nM/TEL-PDGFR1 & PTC3-RET BaF3, ﹤1 nM/FLT3-ITD-expressing MV4-11 & MOLM-13) via binding/stablizing target kinases in the inactive “DFG-out” conformation. AST487 effectively suppresses RET- (NIH3T3-RETC634W & human medullary thyroid cancer (MTC) TT cells) and FLT3-ITD-driven (MV4-11) tumor growth in mice in vivo (20-50 mg/kg/day p.o.).