In Vitro: Ki8751 inhibits VEGFR-2 phosphorylation at an IC50 value of 0.90 nM, and also inhibits the PDGFR family members such as PDGFRR and c-Kit at 67 nM and 40 nM, respectively. However, Ki8751 does not have any inhibitory activity against other kinases such as EGFR, HGFR, InsulinR and others even at 10000 nM. Ki8751 suppresses the growth of the VEGF-stimulated human umbilical vein endothelial cell (HUVEC) on a nanomolar level.
In Vivo: Ki8751 shows significant antitumor activity against five human tumor xenografts such as GL07 (glioma), St-4 (stomach carcinoma), LC6 (lung carcinoma), DLD-1 (colon carcinoma) and A375 (melanoma) in nude mice and also shows complete tumor growth inhibition with the LC-6 xenograft in nude rats following oral administration once a day for 14 days at 5 mg/kg without any body weight loss.