With five approved drugs for hepatitis B, Dr. Rajender Reddy, director of Hepatology at the University of Pennsylvania, helped shed some light on the different options.

For PEG, the data shows there is no real advantage for combination treatment with PEG and lamivudine (LAM) for e-antigen positive or negative patients. However, there is a greater chance of surface antigen loss in e-antigen positive patients with PEG than with lamivudine (3-7% with PEG, and less than 1% with LAM).

For those on lamivudine, the risk of developing drug resistance is decreased if a patient responds by 24 weeks of treatment. In addition, studies show that lamivudine needs to be continued at least 6 months after e-antigen seroconversion to decrease risk of relapse.

Adefovir has a low incidence of resistance compared to lamivudine (18% vs. 70% by the fourth year). Durability of response is long to indefinite (about 90% up to 114 weeks off treatment) and e-antigen seroconversion is about 14% in the first year and 46% by the third year.

Entecavir is the most potent oral HBV antiviral with the greatest suppression of viral DNA. In e-antigen positive patients, DNA suppression less than 400 copies/ml is 69% after one year of entecavir therapy vs. 38% for lamivudine. In e-antigen negative patients the results are similar.

Dr. Reddy concluded that because the hepatitis B virus is so tricky, there is no "one size fits all" answer. More studies need to be done in order to better evaluate what approach will work best for which patient.

BInformed, Fall 2005.