Tumors need a blood supply in order to grow. The process by which blood vessels form is called angiogenesis. The tumor cells send signals out to ask blood vessels to come and nourish them, enabling the tumor to grow in a way that can eventually kill the patient. Antiangiogenesis drugs, like Endostatin, halt the process by blocking blood vessel growth. The tumor starves and disappears.
Researchers say antiangiogenesis holds extraordinary potential.
Most anti-cancer drugs work by poisoning the cancer cells and are, therefore, very toxic. The Phase I study, like all Phase I studies, will primarily determine the safety of the drug, but researchers will be watching for a reduction in tumor size. Investigators say patients with renal cell carcinoma, mesothelioma, breast cancer, and melanoma may be best suited for the Endostatin trial because of the large number of blood vessels feeding those types of tumors.