Background: Chronic hepatitis C virus is difficult to treat and affects approximately 3 million Americans. Protease inhibitors increase the effectiveness of standard therapy, but they are costly. A genetic assay may identify patients most likely to benefit from this treatment advance.
Objective: To assess the cost-effectiveness of new protease inhibitors and an interleukin (IL)-28B genotyping assay for treating chronic hepatitis C virus.
Design: Decision-analytic Markov model.
Data sources: Published literature and expert opinion.
Target population: Treatment-naive patients with chronic, genotype 1 hepatitis C virus monoinfection.
Time horizon: Lifetime.
Intervention: Strategies are defined by the use of IL-28B genotyping and type of treatment (standard therapy [pegylated interferon with ribavirin]; triple therapy [standard therapy and a protease inhibitor]). Interleukin-28B-guided triple therapy stratifies patients with CC genotypes to standard therapy and those with non-CC types to triple therapy.
Outcome measures: Discounted costs (in 2010 U.S. dollars) and quality-adjusted life-years (QALYs); incremental cost-effectiveness ratios.
Results of base-case analysis: For patients with mild and advanced fibrosis, universal triple therapy reduced the lifetime risk for hepatocellular carcinoma by 38% and 28%, respectively, and increased quality-adjusted life expectancy by 3% and 8%, respectively, compared with standard therapy. Gains from IL-28B-guided triple therapy were smaller. If the protease inhibitor costs $1100 per week, universal triple therapy costs $102,600 per QALY (mild fibrosis) or $51,500 per QALY (advanced fibrosis) compared with IL-28B-guided triple therapy and $70,100 per QALY (mild fibrosis) and $36,300 per QALY (advanced fibrosis) compared with standard therapy.
Results of sensitivity analysis: Results were sensitive to the cost of protease inhibitors and treatment adherence rates.
Limitation: Data on the long-term comparative effectiveness of the new protease inhibitors are lacking.
Conclusion: Both universal triple therapy and IL-28B-guided triple therapy are cost-effective when the least-expensive protease inhibitor are used for patients with advanced fibrosis.
Primary funding source: Stanford University.