The purpose of this study is to determine if concentration-controlled ribavirin dosing can achieve a targeted level of plasma exposures and if it appears safe and effective compared with standard weight-based ribavirin dosing. Forty, previously treatment-naive participants with genotype 1 disease will be randomized to receive concentration-guided or standard weight-based ribavirin. Peginterferon alfa 2a,ribavirin, and telaprevir will be provided through the study.