Pazopanib was well tolerated at doses up to 2000 mg daily. Pazopanib is a potent and selective, orally available, small molecule inhibitor of VEGFR-1, -2, and -3, PDGF-α, PDGF-β, and c-kit tyrosine kinases (TKs). The agent selectively inhibits proliferation of endothelial cells stimulated with VEGF but not with basic fibroblast growth factor. In non-clinical angiogenesis models, pazopanib inhibited VEGF-dependent angiogenesis in a dose-dependent manner and in xenograft tumor models, twice-daily administration of pazopanib significantly inhibited tumor growth in mice implanted with various human tumor cells. Upon chronic oral dosing, pazopanib is expected to inhibit VEGF driven angiogenesis and as a consequence, limit solid tumor growth. Because angiogenesis is necessary for the growth and metastasis of solid tumors, and VEGF is believed to have a pivotal role in this process, pazopanib treatment may have broad-spectrum clinical utility.