Currently, there are no effective antiviral treatments to cure HBV infection in patients with chronic hepatitis B. Five drugs have been approved for the treatment of chronic hepatitis B at present: conventional interferon (IFN) alpha, lamivudine, adefovir dipivoxil, pegylated IFN alpha and recently entecavir. Overall, satisfactory virologic and serologic responses could be achieved using pegylated IFN alpha alone in around 20-44% of these patients. Nevertheless, better treatment options are still needed for the remaining >50% non-responders.