Background:

Vatalanib is a novel and potent inhibitor of VEGFR with IC50 value of 77 nM, 27 nM and 37 nM for VEGFR-1 (Flt-1), VEGFR-2 (FLK-1) and VEGFR-2 (KDR), respectively [1].
The vascular endothelial growth factor receptors (VEGFRs) are tyrosine kinases and are receptors for VEGF. VEGF acts as a key factor in pathological situations that involve in pathological situations that involve enhancing vascular permeability as well as neovascularization [1].
In CHO and HUVECs cells transfected with the KDR receptor, Vatalanib inhibited the VEGF-induced phosphorylation of KDR with an IC50 of 34 nM and 17 nM for the CHO and HUVECs cells, respectively. Also, Vatalanib inhibited thymidine incorporation induced by VEGF with IC50 value of 7.1 nM in HUVECs cells. Vatalanib inhibited VEGF-induced endothelial cell proliferation in a dose-dependant way [1].
In a growth factor implant mice model, Vatalanib (12.5, 25 or 50 mg/kg, 6 days) inhibited the angiogenic response around the implant induced by VEGF and PDGF [1]. In a xenograft mouse model, treatment mice with Vatalanib through gastric tube daily caused tumor inhibition rate of 76% [2].  
参考文献:
[1]. Wood JM, Bold G, Buchdunger E, et al. PTK787/ZK 222584, a novel and potent inhibitor of vascular endothelial growth factor receptor tyrosine kinases, impairs vascular endothelial growth factor-induced responses and tumor growth after oral administration. Cancer Res, 2000, 60(8): 2178-2189.
[2]. Paesler J, Gehrke I, Gandhirajan RK, et al. The vascular endothelial growth factor receptor tyrosine kinase inhibitors vatalanib and pazopanib potently induce apoptosis in chronic lymphocytic leukemia cells in vitro and in vivo. Clin Cancer Res, 2010, 16(13): 3390-3398.