To assess the cost-effectiveness of bicalutamide (Casodex™) as adjuvant treatment in early prostate cancer (EPC).
A Markov state transition model was developed, using disease progression rates from a large (N = 8113) clinical trial program comparing bicalutamide in addition to standard care with standard care alone. Utility scores for different disease stages were obtained from published reports. Costs of disease progression were obtained from a retrospective patient chart analysis in six Belgian centers (n = 60). The time horizon was 15 years and the analysis was conducted from the public payer perspective.
The model showed good validity in predicting clinical outcomes. At a time horizon of 15 years, an incremental cost-effectiveness of 27,059€/QALY was obtained. The main factors influencing conclusions included the time horizon, the duration of bicalutamide treatment, which was set at a maximum (5 years) in the base case, and possible differences in prognosis of metastatic cancer between comparators. Also the discounting of health effects significantly altered cost-effectiveness ratios. Many of these influences are inherently associated with any cost-effectiveness analysis related to treatment of early, slowly progressing malignancies because such an analysis requires a sufficient time horizon to include not only the treatment costs but its benefits as well.
Based on the current data, bicalutamide appears to be a cost-effective option for adjuvant treatment of EPC.