Dramatic inhibition of retinal and choroidal neovascularization by oral administration of a kinase inhibitor

The most common cause of new blindness in young patients is retinal neovasc ularization, and in the elderly is choroidal neovascularization. Therefore, there has been a great deal of attention focused on the development of new treatments for these disease processes. previous studies have demonstrated partial inhibition of retinal neovascularization in animal models using an tagonists of vascular endothelial growth factor or other signaling molecule s implicated in the angiogenesis cascade. These studies have indicated pote ntial for drug treatment, but have left many questions unanswered. Is it po ssible to completely inhibit retinal neovascularization using drug treatmen t with a mode of administration that is feasible to use in patients? Do age nts that inhibit retinal neovascularization have any effect on choroidal ne ovascularization? In this study, we demonstrate complete inhibition of reti nal neovascularization in mice with oxygen-induced ischemic retinopathy by oral administration of a partially selective kinase inhibitor that blocks s everal members of the protein kinase C family, along with vascular endothel ial growth factor and platelet-derived growth factor receptor tyrosine kina ses. The drug also blocks normal vascularization of the retina during devel opment but has no identifiable adverse effects on mature retinal vessels. I n addition, the kinase inhibitor causes dramatic inhibition of choroidal ne ovascularization in a laser-induced murine model. These data provide proof of concept that pharmacological treatment is a viable approach for therapy of both retinal and choroidal neovascularization.