Abstract

Age-related macular Degeneration (AMD) is the most common cause of vision loss in patients over the age of 65 years in industrialized nations. Though most patients with AMD have the non-exudative (dry) form, most severe vision loss is due to exudative (wet) macular degeneration. Exudative AMD is characterized by the abnormal growth of neovascular membranes from the choriocapillaris into the subretinal or sub-retinal pigment epithelial space. Though the underlying pathophysiology of choroidal neovascularization is not completely understood, ischemia and inflammation are believed to play important roles. Neovascularization is largely driven by vascular endothelial growth factor A (VEGF-A) with VEGF165 appearing to be the most important isoform. The intravitreal administration of anti-VEGF drugs has become the preferred treatment for exudative macular degeneration. Three drugs are currently approved for the treatment of exudative AMD (pegaptanib, ranibizumab and aflibercept) and bevacizumab is frequently used off- label. Unlike laser photocoagulation and photodynamic therapy which only slowed the loss of vision, the anti-VEGF drugs frequently lead to long-term improvements in visual acuity. Several new anti-VEGF drugs are being developed for the treatment of exudative AMD.

Keywords: Aflibercept, age-related macular degeneration, bevacizumab, choroidal neovascularization, pegaptanib, ranibizumab, vascular endothelial growth factor, VEGF, neovascularization, Visudyne