Two angiogenesis blockers, Macugen from Eyetech and LY33531 from Eli Lilly, are in advanced (phase III) clinical trials for age-related macular degeneration---the leading cause of blindness in Western countries--and diabetic retinopathy, respectively. Other angiogenesis blockers are in earlier stages of experimentation for both disorders, which are caused by uncontrolled growth of capillaries in the retina, although each with different mechanisms.
Recently, researchers have found that a single protein, called Vascular Endothelial Growth Factor, is responsible for the anomalous growth of blood vessels in the retina, leading them to try angiogenesis blockers in the treatment of these disorders. This field of research has increased enormously in the last few years. "There were 3,500 oculists attending the session on angiogenesis at the last ARVO [Association for Research in Vision and Ophtalmology] meeting," says Judah Folkman.--Sergio Pistoi and Chiara Palmerini
