Cost-effectiveness analysis of interferon as adjuvant therapy in high-risk melanoma patients in Spain

In the randomised clinical trial E1684, the administration of interferon (IFN) alpha-2b resulted in prolonged disease-free and overall survival in high-risk melanoma patients following surgical resection. However, and considering the cost and toxicity of IFN, the convenience of its widespread use should be evaluated. The aim of this study was to analyse the cost-effectiveness ratio of adjuvant therapy with IFN alpha-2b in melanoma patients versus an untreated control group. A Markov model was used to compare two hypothetical cohorts of 1000 patients aged 50 years, according to the clinical outcome of the E1684 study. The cohort of patients treated with IFN alpha-2b has an increased overall survival of 1.90 years during the patient's lifetime. The incremental discounted cost per life year gained of IFN versus observation is 9015 Euros according to the projection generated by the model. The sensitivity analysis demonstrated that changes in the most relevant study end-points do not modify the study outcome. In conclusion, in high-risk melanoma patients following surgical resection, the cost-effectiveness of IFN alpha-2b (at a dose of 20 MU/m²/day, 5 days per week for one month, followed by 10 MU/m² TIW, up to one complete year of therapy) versus an untreated control group is within the limits established in health economics to determine if adoption of a new treatment is economically justified and is comparable with other interventions in which cost-effectiveness is acceptable to the National Health System.