Fighting cancer by targeting the blood vessels that feed tumors is a well-documented and validated approach to therapy. Dr. Judah Folkman detailed the concept in his ground-breaking paper ‘Tumor Angiogenesis, a Therapeutic Approach' in the New England Journal of Medicine in 1971. More recently, anti-angiogenic agents such as bevacizumab, which limit tumor growth by preventing the formation of new blood vessels, have been approved for some indications and are widely used to treat solid tumors. While both agents target tumors through blood vessels, VDAs and anti-angiogenic agents work in different, yet complementary ways.