Formation of new blood vessels (angiogenesis) is important for tumor growth in advanced
cancer. It is known that tumors make a protein called vascular endothelial growth factor
(VEGF). VEGF stimulates the formation of blood vessels that supply the tumor with nutrients
and oxygen. PTC299 is an oral investigational new drug that has been shown to decrease
production of VEGF in animal models of human cancer. In these animal models, oral PTC299
administration decreases VEGF levels in the tumor and in the bloodstream, decreases blood
vessel numbers in the tumor, and significantly slows or halts tumor growth. When given in
combination with the chemotherapeutic drug, docetaxel, PTC299 increases the antitumor
activity over use of docetaxel alone. Safety studies in research animals indicate good
tolerability at doses and drug levels that are higher than those planned for the clinical
studies. Results from Phase 1a studies in healthy volunteers indicate that PTC299 achieves
levels of PTC299 in the bloodstream that are known to be active in animal models of human
cancer. This Phase 1b study is designed to test the hypothesis that PTC299 will be tolerable
and will show evidence of anti-VEGF and antitumor activity when administered orally to
participants with cancer.