A health economic model to assess the cost-effectiveness of PEG IFN alpha-2a and ribavirin in patients with mild chronic hepatitis C.

According to the current guidelines, it is advised not to treat patients with mild chronic hepatitis C. However, discussions as to giving immediately a treatment (direct treatment) to these patients have started and the incremental cost-effectiveness ratio (ICER) of such strategy is still unknown. The aim of this study was to estimate, in the health care payer perspective, the ICER of a direct treatment of patients with mild chronic hepatitis C in comparison with the strategy of monitoring these patients and treat them when the disease will progress to the state of moderate chronic hepatitis. The treatment assessed was the current standard treatment composed of pegylated interferon alpha-2a and ribavirin. At the beginning of the study, patients were aged 45. Long-term economic and clinical outcomes over a 30-year period were predicted using a Markov simulation model. Data were obtained from published literature. Monte Carlo simulations were used to determine 95% confidence intervals of results. The ICER of a direct treatment with PEG IFN alpha-2a and ribavirin is 23,046 euro/QALY (CI 95% 3,882 euro-42,392 euro) for genotypes 1-4-5-6 and 4,631 euro/QALY (CI 95% 797 euro-7,881 euro) for genotypes 2-3. Sensitivity analysis shows that it is only in extreme circumstances related to the utilities that the ICER for genotypes 1-4-5-6 is unacceptably high for the society (>50,000 euro). Even though a direct treatment is more expensive, it gives the advantage of curing greater number of patients and of increasing quality-adjusted life-years (QALYs), implying that such strategy is generally cost-effective at a threshold of 50,000 euro/QALY.