What is the impact of a country-wide scale-up in antiviral therapy on the characteristics and sustained viral response rates of patients treated for hepatitis C?

Background & Aims: The global burden associated with hepatitis C virus (HCV) infection has prompted a scale-up of antiviral therapy. Hitherto, no data exist on the impact of scaling-up, on the characteristics of treated populations, or on sustained viral response (SVR) rates. We assessed the country-wide scale-up of antiviral therapy in Scotland, a country which nationally monitors uptake of and response to HCV treatment.
Methods: Data for patients, initiated on combined pegylated interferon and ribavirin therapy at 13 specialist HCV clinics in 2001–2010, were extracted from the Scottish HCV Clinical Database (n = 3895). Patient characteristics included age, genotype, PWID (people who inject drugs) status, prison referral, and diagnosed cirrhosis. Temporal trends in covariates and adjusted effects on a SVR were examined via mixed-effects regression.
Results: The number of patients starting treatment increased from 237 in 2001–2002 to 1560 in 2009–2010, with an increasing trend in SVR from 44% to 57% over this period. For a given clinic, between 2001/2 and 2010 there was a decrease in the odds of those treated being diagnosed with cirrhosis (odds ratio [OR] = 0.84 per year), and increasing temporal trends for those treated being PWID (OR = 1.08) and prison referrals (OR = 1.06). Adjusting for covariates, the proportion of a given clinic’s patients achieving SVR was positively associated with the percentage of PWID (OR = 1.01 per percent increase; 95% confidence interval [CI]: 1.00–1.02) and genotype 2/3 (OR = 1.03; 95% CI: 1.02–1.04).
Conclusions: Despite changes in patient characteristics, a country-wide scale-up of antiviral therapy did not compromise SVR rates. Results are highly relevant to countries planning on scaling-up treatment, given the forthcoming availability of new interferon-free therapies.