OBJECTIVES: The aim of the study was to evaluate the cost-effectiveness of peginterferon alfa-2a (40KD) for the treatment of patients with HBeAg-negative chronic hepatitis B in Poland. The analysis compared two strategies: peginterferon alfa-2a (40KD) vs. lamivudine for 48 weeks(short-term analysis) or peginterferon alfa-2a (40KD) for 48 weeks vs. lamivudine for 4 years (long-term analysis). METHODS: The analysis was performed from the Polish payer perspective using a state-transition Markov model. Quality-adjusted life years (QALYs) was adopted as a measure of effectiveness. Efficacy with peginterferon alfa-2a (40KD) and lamivudine after 48 weeks of treatment was obtained from a randomized controlled trial (Marcellin et al. NEJM 2004;351(12):32-43). Long-term lamivudine efficacy, health state transition probabilities and utility estimates were obtained from the published literature. Direct medical costs, i.e. cost of drugs and procedures in the treatment of hepatitis B and its complications (cirrhosis, hepatocellular carcinoma, liver transplantation) were obtained from Polish sources. Costs and benefits were discounted at a 3% annual rate. RESULTS: Peginterferon alfa-2a 40(KD) vs. lamivudine for 48 weeks (short-term analysis) increased QALYs by 0,89. The mean treatment cost in the short-term analysis was 17 743 € (1 € = 4.035 PLN) and 12 522 € per patients for peginterferon alfa-2a and lamivudine, respectively. The incremental cost-effectiveness ratio (ICER) was 9 316 €/QALY gained. In the long-term analysis, peginterferon alfa-2a (40KD) increased QALYs by 0,75. The mean cost of treatment was 17 €398 for peginterferon alfa-2a (40KD) and €13,890 for lamivudine per patient. The incremental cost-effectiveness ratio (ICER) was €7643 per QALY gained. CONCLUSION: The ICER for peginterferon alfa-2a evaluated in the short-term analysis as well as in the long-term analysis did not exceed €14,870 (cost of one year dialysis in Poland). Thus, the procedure appears to be cost-effective in Poland.