Interferon alpha therapy is a generally accepted agent for the treatment of chronic HBV infection and effective in about one third of patients. Recently, in the HBV 99-01 study, pegylated interferon alpha-2b (PEG-IFN) has been shown to be effective in HBeAg-positive patients with chronic hepatitis B. In this study, 266 patients were randomized to receive PEG-IFN in combination with either lamivudine or placebo for 52 weeks.

Thirty-six percent of patients receiving monotherapy and thirty-five percent receiving combination therapy had lost serum HBeAg at the end of the 26 week post-treatment follow-up period and there was no difference between treatment groups (P = 0.91). More patients on combination therapy initially seroconverted (44% of patients, compared with 29% on monotherapy; P = 0.01) at the end of treatment but relapsed during follow-up. Similar response patterns were seen when response was assessed by DNA suppression and change in ALT levels.

In contrast to nucleoside analogues, such as lamivudine and adefovir dipivoxil, the virological and biochemical response to standard alpha-interferon has been shown to be durable after treatment discontinuation.In addition, standard alpha-interferon leads to improved survival and reduction of hepatocellular carcinoma in chronic hepatitis B patients.Pegylated interferons have shown to be effective in HBeAg-positive chronic hepatitis B patients, but the durability of the response and long-term outcome of treatment have yet to be established.