Treatment algorithm for chronic hepatitis B in HIV-infected patients

Recommendations for the treatment of chronic hepatitis B (CHB) in HIV-infected patients is complex due to the lack of controlled trials and the dual activity of therapeutic agents on both viruses. Thus, proposals for optimal anti-HBV therapy in HIV-infected patients should be pragmatic using the knowledge from HBV mono- and HIV/HBV co-infected studies. There are four approved drugs for the treatment of CHB which include interferon alpha (IFN), lamivudine (LAM), entecavir (ETV) and adefovir dipivoxil (ADV). LAM, tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) are approved for HIV and active against HBV. Studies with IFN are limited in HIV/HBV co-infected patients but suggest a decreased response compared with HBV mono-infected patients. LAM and FTC are effective against HBV but are associated with a high rate of HBV resistance. ETV, ADV and TDF are effective against wild-type and LAM-resistant HBV with a favourable resistance profile shown for ADV and TDF. Interferon, ADV or ETV are the preferable drugs in HBV naive patients who do not require HIV therapy. Combination of TDF plus FTC or LAM should be proposed in patients with therapeutic indication for both viruses. TDF should be included in the anti-retroviral regiment of patients with HBV resistance to lamivudine.