Supplementary Material for: Cost-Effectiveness of IL28Β Genotype-Guided Protease Inhibitor Triple Therapy versus Standard of Care Treatment in Patients with Hepatitis C Genotypes 2 or 3 Infection

Background/Aims: Triple therapy [adding protease inhibitors to standard of care (SOC)] dramatically increases treatment response in selected patients with hepatitis C virus (HCV). Interleukin 28B (IL28Β) genotyping helps predict responsiveness in these patients; however, the economic implications of IL28Β genotyping in HCV genotype 2 or 3 infected patients are unknown. Short- and long-term costs and outcomes of SOC therapy were calculated and used to determine the cost-effectiveness thresholds for using triple therapy in HCV genotype 2 or 3 infected patients. Methods: Costs and outcomes were calculated by conducting cohort simulations on decision trees modeling SOC and triple therapy. Quality-adjusted life expectancies and long-term costs were predicted through Markov modeling. Results: For triple therapy to be cost-effective, sustained virologic response (SVR) rates must improve (depending on age) by 7.91-11.11 and 9.06-12.8% for HCV genotype 2 and 3 cohorts, respectively. When triple therapy is guided by 2 IL28Β variants, a 2.63-3.72% improvement in SVR is needed for cost-effectiveness, and when guided by only one variant, a 1.4-8.91% improvement is needed. Conclusions: Markov modeling revealed that modest increases in SVR rates from IL28Β-guided triple therapy can lead to both lower costs and better health outcomes than SOC therapy in the long run.