OBJECTIVES Current Thai guidelines reimburse peginterferon/ribavirin (PR) combination treatment for patients infected with all genotypes of chronic hepatitis C (CHC), based on the results of cost-effectiveness studies. Two trials, SPRINT-2 and RESPOND-2, have demonstrated that treatment with Boceprevir (BOC) in addition to PR results in significantly higher sustained virologic response rates than the current standard of care, PR alone for 48 weeks, in both treatment naïve and treatment experienced CHC genotype 1 patients. The aim of our analysis was to evaluate the cost-effectiveness of BOC-based treatment compared with PR alone from the perspective of the policy maker in Thailand over a lifetime horizon. METHODS A decision analytic model was developed to simulate the treatment strategies described in the BOC label (BOC/PR) and PR alone, and to describe the natural history of CHC to make projections beyond the treatment phase. Separate analyses were conducted based on patients' treatment history and cirrhosis status. Patient characteristics were obtained from SPRINT-2 and RESPOND-2. Treatment characteristics including efficacy and the rate of side effects were obtained from subset analyses of these trials. Transition probabilities, costs, and health state utilities were obtained from previously studies. We projected the lifetime cumulative incidence of CHC-related liver complications – decompensated cirrhosis, hepatocellular carcinoma, liver-transplantation, liver-related mortality - discounted costs and QALYs associated with each treatment strategy. The incremental cost-effectiveness ratio was also assessed. RESULTS For treatment naïve and treatment experienced patients, BOC/PR treatment is projected to reduce the incidence of CHC-related liver complications by 43-44% and 47-51%. BOC/PR is projected to be less expensive and result in increases of 0.13-2.62 QALYs for all non-cirrhotic patients and cirrhotic treatment-experienced patients.  Cirrhotic treatment naïve patients was the only subgroup in which cost-effectiveness was not demonstrated.   CONCLUSIONS In the Thai setting, BOC/PR is projected to be cost-savings against PR alone in the majority of CHC genotype 1 patients, regardless of treatment history.