Pegaptanib sodium for neovascular age-related macular degeneration: clinical experience in the UK

The pathogenesis of age-related macular degeneration (AMD) is unclear, but it can take either a neovascular/exudative/wet form, characterized by choroidal neovascularization (CNV), or a dry form. No treatments are available for the dry form, but there are a number of pharmacological interventions that inhibit vascular endothelial growth factor (VEGF), which is central to the pathogenesis of CNV and neovascular AMD. Available anti-VEGF agents either target all active VEGF isoforms (eg, ranibizumab), or take a more selective approach and inhibit only VEGF(165) (eg, pegaptantib sodium). Current guidance on their use is equivocal and restrictive at best, resulting in associated difficulties in securing adequate, timely funding for treatment. The Moorfields Eye Hospital undertook an audit of 70 patients receiving intravitreal (ITV) pegaptanib sodium on a pro re nata (prn) dosing schedule. Despite initial funding delays, the audit recorded superior treatment outcomes compared with those reported in the VISION trials at 12 weeks: 88% of audit patients maintained stable vision, 29% gained vision and 6% experienced severe vision loss compared with 70%, ≥6% and ≤10% of patients in VISION at 54 weeks, respectively. The audit indicates a positive correlation between patients with better baseline visual acuity (VA) and improved therapeutic benefits, including a greater likelihood of both vision gain and vision preservation. Experience at Moorfields also suggests that pegaptanib sodium is more useful in occult lesions than minimally classic lesions, and clinical experience suggests that combination therapies may offer the best approach with anti-VEGF therapies. Further randomized clinical trials will help better determine the optimal treatment strategies with pegaptanib sodium in neovascular AMD.