VEGFA and age-related macular degeneration: Pegaptanib, a 27-nt RNA aptamer that specifically binds to vascular endothelial growth factor (VEGF), is the first therapeutic aptamer approved by the US Food and Drug Administration as an antiangiogenic medicine that can treat neovascular age-related macular degeneration by inhibiting intraocular blood vessel growth (Moshfeghi & Puliafito, 2005).