COST-EFFECTIVENESS OF 72-WEEK VS. 48-WEEK TREATMENT WITH PEGINTERFERON PLUS RIBAVIRIN IN CHRONIC HEPATITIS C GENOTYPE 1-INFECTED JAPANESE PATIENTS

Purpose: Extended peginterferon plus ribavirin treatment for 72 weeks has been shown to be more effective than the standard 48 weeks of this treatment in patients with late virological responder (LVR) of genotype 1 chronic hepatitis C virus infection (CHC). The purpose of this study was to evaluate the cost-effectiveness of this extended-duration treatment compared with standard-duration treatment in Japanese patients.

Method: We created a Markov decision model of HCV natural history and progression toward advanced liver disease to evaluate the cost-effectiveness of alternative treatment strategies, in a previously untreated Japanese cohort of CHC patients aged 50 years using a lifetime time horizon. We compared three strategies: no treatment, standard treatment (48 wks), and extended (72 wks) treatment with peginterferon-α2b + ribavirin. The data sources of the natural history model were derived mainly from Japanese epidemiological studies. The data of effectiveness of extended treatment in the CHC genotype 1 infected late viral responders was derived from systematic reviews by Cochrane collaboration. The costs for treatment of CHC and complication liver disease such as liver cirrhosis or hepatocellular carcinoma were obtained from insurance claim data in our hospital.

Result: Our model estimated that the standard and extended duration strategies could yield 0.47 and 0.49 of the sustained viral response, respectively. In the base case analysis, the extended-treatment (72-wk) strategy could increase by 0.12 and 3.11 the quality-adjusted life years compared to the standard and no-treatment strategies, and a lifetime of no treatment was more costly than the other strategies. The extended-treatment strategy produced an incremental cost-effectiveness ratio (ICER) of 0.38 million yen per quality-adjusted life-year gained versus the standard-treatment strategy. Sensitivity analyses showed that the lower rate of sustained viral response (SVR) provided by the extended treatment relative to the standard treatment increased the ICER significantly, whereas the model results were relatively insensitive to other inputs. The probabilistic sensitivity analysis showed that the extended treatment would be cost-effective in cases of more than 98% probability at conventional willingness-to-pay thresholds.

Conclusion: Extended (72 weeks’) treatment with peginterferon + ribavirin would be a fairly cost-effective strategy compared to standard (48 weeks’) treatment for untreated patients chronically infected with HCV of genotype 1 in Japan.