Cost analysis of sofosbuvir/ribavirin versus sofosbuvir/simeprevir for genotype 1 hepatitis C virus in interferon-ineligible/intolerant individuals

Abstract

Treatment guidance for chronic hepatitis C (CHC) released by the American Association for the Study of Liver Diseases (AASLD) and the Infectious Diseases Society of America (IDSA) offers two options for interferon (IFN)-ineligible/intolerant individuals with genotype 1 infection: sofosbuvir/ribavirin (SOF/RBV) for 24 weeks or sofosbuvir/simeprevir (SOF/SMV) for 12 weeks. A 24-week course of SOF/RBV costs approximately US$169,000, with sustained virologic response (SVR) rates ranging from 52% to 84%; 12 weeks of SOF/SMV costs approximately $150,000, with SVR between 89% and 100%. Because SOF/SMV is currently used off-label, debate exists among physicians and payers about whether it should be prescribed and covered. This article presents a cost-effectiveness analysis of these two treatment regimens accounting for costs of drugs, treatment-related medical care, retreatment for individuals who do not achieve SVR, and natural history of continued HCV infection after failed retreatment. Analysis uses a Markov model with a lifetime horizon and a societal perspective. In the base-case scenario, SOF/SMV dominated SOF/RBV in a modeled 50-year-old cohort of treatment-naïve and -experienced subjects, excluding those who failed earlier therapy with telaprevir or boceprevir. SOF/SMV yielded lower costs and more quality-adjusted life years (QALYs) for the average subject, compared to SOF/RBV ($165,336 and 14.69 QALYs vs. $243,586 and 14.45 QALYs, respectively). In base-case cost analysis, the SOF/SMV treatment strategy saved $91,590 per SVR, compared to SOF/RBV. Under all one-way sensitivity scenarios, SOF/SMV remained dominant and resulted in cost savings.

Conclusions: These results suggest that a 12-week course of SOF/SMV is a more cost-effective treatment for genotype 1 CHC than 24 weeks of SOF/RBV among IFN-ineligible/intolerant individuals, supporting the AASLD/IDSA guidance and offering implications for both clinical and regulatory decision making as well as pharmaceutical pricing.

Figure 1. Simplified Markov Model

HCV+ model subjects progress through fibrosis stages F0-F4, DC, and HCC based on annual probabilities. Those who fail treatment can be re-treated with rescue therapy; those who fail re-treatment continue progressing through CHC natural history. Further fibrosis progression after SVR is possible for subjects in stages F3 and F4, and F3 subjects can progress directly to DC or HCC, bypassing F4 (dotted lines). CHC = chronic hepatitis C; DC = decompensated cirrhosis; F0-F4 = Metavir fibrosis stages; HCC = hepatocellular carcinoma; HCV = hepatitis C virus; Re-tx = re-treatment; SVR = sustained virologic response; Tx = treatment.

Figure 2. Decision tree excerpt

A selection from the decision tree underlying the Markov model, where M represents the starting point for each annual model cycle in the two treatment arms. Subjects who fail treatment and re-treatment continue progressing through CHC natural history in the subsequent model year. *SVR rates vary by fibrosis stage (not depicted). HCV = hepatitis C virus; CHC = chronic hepatitis C; SOF/RBV = 24-week sofosbuvir + ribavirin treatment regimen; SOF/SMV = 12-week sofosbuvir + simeprevir treatment regimen.