Sofosbuvir for Previously Untreated Chronic Hepatitis C Infection

To the Editor: In their article on the use of sofosbuvir in previously untreated patients with chronic hepatitis C virus (HCV) infection in two phase 3 studies (May 16 issue),(1) Lawitz et al. conclude that the addition of sofosbuvir was effective in patients who were infected with HCV genotype 1, 4, 5, or 6 (NEUTRINO trial). However, response rates in the group that received sofosbuvir and ribavirin were lower among patients with genotype 3 infection than among those with genotype 2 infection (FISSION trial). Although for the latter trial, the authors provide data on the presence or absence of cirrhosis, ...