Using contrast sensitivity to estimate the cost-effectiveness of verteporfin in patients with predominantly classic age-related macular degeneration

Abstract

To re-evaluate the cost-effectiveness of photodynamic therapy with verteporfin (Visudyne, Novartis AG, Switzerland) in patients with predominantly classic and classic choroidal neovascularization (CNV) owing to age-related macular degeneration (AMD), using new evidence on the impact of contrast sensitivity on health status. A health economic model is used to synthesise the evidence on contrast sensitivity and treatment rates from the TAP Investigation with health state utilities and costs. Impairment of visual function is estimated using a Markov model to predict transitions between states of contrast sensitivity. Each state is associated with costs and a health state utility. Total expected costs and benefits for a cohort of patients over a defined number of cycles are calculated. The expected health state utility for each disease state was estimated using results from a study of 209 patients with AMD in Sheffield. The model includes the costs associated with treatment and monitoring in the verteporfin treatment arm and costs offset by delaying the deterioration of visual function. Beyond 3 years, the annual costs of the verteporfin arm are estimated to be less than the annual costs of the control arm, owing to the cost associated with higher blindness prevalence in the control arm. Over time, the results show that both the incremental utility and cost decreases. By 10 years, the estimated incremental cost-effectiveness is approximately pound20 996 per Quality-Adjusted Life Years. The results of this study suggest that the verteporfin therapy in the treatment for patients with predominantly classic and classic CNV owing to AMD is encouraging.