indication

For the treatment of neovascular (wet) age-related macular degeneration.

pharmacology

Pegaptanib is a selective vascular endothelial growth factor (VEGF) antagonist. VEGF is a secreted protein that selectively binds and activates its receptors located primarily on the surface of vascular endothelial cells. VEGF induces angiogenesis, and increases vascular permeability and inflammation, all of which are thought to contribute to the progression of the neovascular (wet) form of age-related macular degeneration (AMD), a leading cause of blindness. VEGF has been implicated in blood retinal barrier breakdown and pathological ocular neovascularization.

mechanism of action

Pegaptanib binds to the major pathological VEGF isoform, extracellular VEGF165, thereby inhibiting VEGF165 binding to its VEGF receptors. The inhibition of VEGF164, the rodent counterpart of human VEGF165, was effective at suppressing pathological neovascularization.

biotransformation

Based on preclinical data, pegaptanib is metabolized by endo- and exonucleases.

absorption

In animals, pegaptanib is slowly absorbed into the systemic circulation from the eye after intravitreous administration.

half life

In humans, after a 3 mg monocular dose (10 times the recommended dose), the average (± standard deviation) apparent plasma half-life of pegaptanib is 10 (± 4) days.