A Preliminary Benefit-Risk Assessment of Verteporfin in Age-Related Macular Degeneration

The prevalence of neovascular age-related macular degeneration (AMD) is expected to increase significantly during the next 20 years. New treatment alternatives to laser photocoagulation are on the horizon — the first of these, photodynamic therapy (PDT) with verteporfin, was approved by the US FDA in 2000. In this article we present a preliminary risk-benefit assessment of verteporfin in AMD, focusing on the landmark randomised, double-blind, placebo-controlled studies. The TAP (Treatment of Age-related macular degeneration with Photodynamic therapy) trial established the efficacy of PDT for classic subfoveal neovascularisation in AMD at 2 years follow-up. The VIP (Verteporfin in Photodynamic therapy) study concentrated on subfoveal occult-only lesions not included in the TAP study. After 2 years, treated eyes were less likely to experience visual loss. Exploratory analyses of TAP and VIP suggest that lesion size is a more significant predictor of the treatment benefit than either lesion composition or visual activity. The VIM (Visudyne® in Minimally classic) trial altered the standard PDT light fluence rate in the treatment of subfoveal minimally classic lesions. This trial again demonstrated a beneficial effect for those receiving treatment with PDT. The VIO (Visudyne® in Occult) trial, evaluating PDT in occult-only lesions as a confirmatory study of the VIP trial, did not achieve its primary end-point at 2 years. Further analyses are pending.

PDT with verteporfin has an excellent safety profile that has been established with >1 million treatment applications. Cost-effectiveness data are limited but suggest that PDT may be a cost-effective treatment modality. Other FDA-approved treatments (pegaptanib, ranibizumab and bevacizumab) for neovascular AMD are discussed, as well as investigational substances such as anecortave acetate.