
Combination therapy with pegylated interferon alfa-2a or alfa-2b and ribavirin (RBV) results in a greater rate of sustained virologic response (SVR) than that seen with standard interferon alone. Patients infected with hepatitis C virus genotype 1 require higher doses of RBV and a longer duration of therapy than do patients infected with genotype 2 or 3. Closely monitor patients for neuropsychiatric effects, especially depression, and hematologic and other toxicities. Because of the teratogenicity of RBV, strict birth control must be used throughout the course of treatment and for 6 months afterwards. Patients who have not demonstrated a 100-fold reduction in viral load after 12 weeks of therapy are unlikely to achieve SVR; discontinuation of therapy may be considered.
