Treatment of chronic hepatitis C infection with peginterferons plus ribavirin

Interferon monotherapy provided the first hope for patients with chronic hepatitis C that the virus could be permanently eradicated. An important development in treating this disease was the recognition that the effects of interferon could be greatly enhanced by combining it with ribavirin, a nucleoside analogue. This combination regimen essentially doubled the sustained virological response rates seen with interferon alone. Recently, modified forms of interferon have been developed that-when used in combination with ribavirin-demonstrate even better efficacy. Thus, peginterferon alfa-2a (Hoffman LaRoche, Nutley, NJ) and peginterferon alfa-2b (Schering-Plough, Kenilworth, NJ) are the latest innovations for the treatment of chronic hepatitis C. The addition of a polyethylene glycol molecule to the native interferon protein favorably alters the pharmacokinetic profile, allowing for once-weekly administration, and leads to superior efficacy compared to standard interferon preparations. This article reviews the data from clinical trials of peginterferon alfa-2a and peginterferon alfa-2b.