FLT4 and neoplasm: Potent dual VEGFR3 and VEGFR2 inhibitor (VEGFR3 IC50 = 1.15 nM, VEGFR2 IC50 = 3.56 nM). It effectively suppresses both lymphangiogenesis and angiogenesis in a 3D-microfluidic tumor lymphangiogenesis assay and in vivo corneal assay.