Management of patients co-infected with hepatitis B virus and HIV.

The management of chronic hepatitis B virus (HBV) infection poses specific problems in the presence of HIV co-infection, since therapeutic approaches have to consider both HBV and HIV infections. There are currently four drugs approved for the treatment of chronic HBV infection (interferon alpha, lamivudine, adefovir, and entecavir); the dual antiviral activity of tenofovir and emtricitabine broadens the armamentarium against HBV in HBV/HIV co-infected patients. Nucleotide analogues--eg, adefovir and tenofovir--have the advantage of a higher genetic barrier to the development of resistance compared with nucleoside analogues--eg, lamivudine and emtricitabine. Fortunately, the two families do not share resistance mutations, allowing salvage therapy and the possibility of combination therapy for drug-naive individuals. Although response to interferon alpha is poorer in HBV/HIV co-infected patients compared with HIV-negative individuals, especially in hepatitis B e antigen-negative HBV infection, the more potent pegylated forms of interferon alpha have brought new hope.