NCIt definition : A 28-mer RNA aptamer covalently linked to two branched 20-kD polyethylene glycol (PEG)
chains, with anti-angiogenic activity. Pegaptanib binds and blocks the activity of
the extracellular vascular endothelial growth factor, specifically the 165-amino acid
isoform (VEGF165). This prevents VEGF165 from binding to VEGF receptors, thereby blocking
angiogenesis as well as preventing VEGF165-induced increases in vessel permeability.
VEGF165 is preferentially involved in pathological ocular neovascularisation.;