Treatment of chronic hepatitis B with interferon-alpha: cost-effectiveness in developing countries

Treatment with interferon-alpha (IFN) has been shown to be cost-effective in developed countries. However, cost-effectiveness In developing countries such as India has not been studied.

Using the Markov transitional probability model, we studied two cohorts of young patients (30 years of age) with chronic hepatitis B, one untreated and the other treated with interferon (IFN), 5 million units daily for 16 weeks, with evidence of viral replication and chronic hepatitis, but not cirrhosis, and were followed up over a 30-year period. Rates of disease progression, efficacy of IFN and quality of life associated with various disease states were estimated from the available literature. Direct costs were estimated using Indian prices of IFN and from the usual costs of medical treatment in India based on expert opinion. Unrelated mortality rates were modelled on age-specific death rates of the general population. The efficacy of IFN was judged In terms of extra life-years and quality-adjusted life-years (QALY) gained, and marginal cost-effectiveness and cost-utility. Several sensitivity analyses, both undiscounted and with discounted analyses, were done.

At the end of the 30-year period, fewer patients in the IFN-treated group developed cirrhosis or decompensated cirrhosis, or were dead. The average life span of the treated cohort was 25.14 years, a gain of 0.6 years over the untreated cohort (24.54years). The QALY lived bythetwocohortswere 23.69 and 22.75 years, respectively, representing a gain of 0.94 years for the IFN-treated group. The cost Incurred by the IFN-treated group was Rs 300,000, and that for the untreated cohort was Rs 40 700, a substantial difference. Using the baseline estimates, undiscounted costs per year of life gained and per QALY gained were Rs 432,500 and Rs 276,900, respectively; these estimates are 20.5 and 13.1 times the per capita gross national income of the Indian population. Sensitivity analyses showed that changes in various parameters led to only minor changes in these estimates. Use of discounting led to an increase in marginal cost per life-year or QALY gained.

In developing countries with a low per capita Income, IFN therapy for chronic hepatitis B may not be cost-effective. A careful consideration of cost-effectiveness is therefore essential before Instituting IFN therapy in patients with chronic hepatitis B In such populations.