Angiopoieten 1 is a ligand for the endotheiium-specific receptor tyrosine kinase, TIE-2 is a novel angiogenic factor [1].Inhibition of TIE-2 is expected to serve to disrupt remodeling and maturation of new vasculature initiated by angiogenesis, thus disrupting the angiogenic process. Inhibition at the kinase domain binding site of VEGFR-2 would block phosphorylation of tyrosine residues and serve to disrupt initiation of angiogenesis.