Evaluación económica de ranibizumab en la degeneración macular neovascular asociada a la edad

Résumé

Background: Ranibizumab is a humanized murine monoclonal antibody fragment (fab) directed against the vascular endothelial growth factor approved for the treatment of neovascular age-related macular degeneration (nvAMD). Ranibizumab was more efficacious and also more expensive than available treatments. We sought to examine ranibizumab cost-effectiveness in the treatment of nvAMD in Spain compared to verteporfin photodynamic therapy (PDT) under a third party-payer perspective, and compared to pegaptanib under a societal perspective. We sought to estimate budgetary impact secondary to ranibizumab adoption, and to analyze parameter uncertainty with regards to the adoption of ranibizumab in order to prioritize future investigations in this field. Methods: We constructed a markov model with five states defined by VA in the better-seeing eye and a death state. Efficacy parameters were obtained from published clinical trials, state utilities were obtained from the literature, and resource use was determined by an ophthalmologist. We conducted an analysis from the societal perspective for which we took direct medical costs not related to nvAMD and non-medical costs from an observational study in the Spanish setting. We conducted extensive sensitivity analyses including probabilistic sensitivity analyses (PSA). For the budgetary impact analysis we took European prevalence from the literature. We undertook expected value of perfect information (EVPI) analysis to analyze uncertainty regarding the adoption decision. Results: In a two-year time horizon ranibizumab provided more QALYs than either PDT or pegaptanib with a calculated incremental cost per QALY when dosed monthly of ¿131,275 and ¿119,953, respectively. When dosed as-needed, ICERs compared to PDT and pegaptanib were reduced to 29,566 and 20,472 ¿/QALY, respectively in the same time horizon, with a probability of the ICERs being below the ¿30,000/QALY threshold of 53,5% and 60,3%. Estimated budget impact surpassed ¿170 million. EVPI revealed that parameters associated with the greater uncertainty were the number of ranibizumab injections and the utilities associated with health states in the model. Conclusions: Ranibizumab is not cost-effective according to the advocated threshold of ¿30,000/QALY in Spain when dosed on a monthly basis in the two year time horizon. Variables which had the greatest impact on the ICER were the selected time horizon and the number of ranibizumab injections. Deterministic ICERs were below the ¿30,000/QALY when ranibizumab was dosed as-needed, but significant uncertainty surrounded the decision.