Nonresponder patients with hepatitis C virus genotype 2/3 infection: a question of low systemic interferon concentrations?

Twelve of 303 per-protocol patients were nonresponders in a 12-week versus 24-week treatment study of hepatitis C virus (HCV) genotype 2/3 infection. The nonresponders had significantly lower interferon concentrations, as well as significantly greater mean age, body mass index, and viral load. Suboptimal drug concentrations may thus contribute to lack of response to therapy in patients with infection due to HCV genotype 2/3.