Randomized trial evaluating the impact of ribavirin mono-therapy and double dosing on viral kinetics, ribavirin pharmacokinetics and anemia in hepatitis C virus genotype 1 infection

In this pilot study (RibaC), 58 hepatitis C virus (HCV) genotype 1 infected treatment-naïve patients were randomized to (i) 2 weeks ribavirin double dosing concomitant with pegylated interferon-α (pegIFN-α), (ii) 4 weeks ribavirin mono-therapy prior to adding pegIFN-α, or (iii) standard-of-care (SOC) ribavirin dosing concurrent with pegIFN-α. Four weeks of ribavirin mono-therapy resulted in a mean 0.46 log₁₀ IU/mL HCV RNA reduction differentially regulated across IL28B genotypes (0.89 vs. 0.21 log₁₀ IU/mL for CC and CT/TT respectively; P = 0.006), increased likelihood of undetectable HCV RNA week 4 after initiating pegIFN-α and thus shortened treatment duration (P