Virological and Clinical Anti-Hepatitis B Virus (HBV) Efficacy of Tenofovir and Emtricitabine in Patients With HIV/HBV co-Infection

This is a randomized multicentre trial of emtricitabine (FTC) versus tenofovir (TDF)/FTC in antiretroviral naive subjects with HIV/HBV co-infection over 48 weeks (Clinical Trial A). Plus, a 12 week viral kinetic substudy comparing a subgroup of patients on Clinical Trial A is being conducted. (Substudy A1)

This is a randomized multicentre trial of FTC vs TDF/FTC in antiretroviral naive subjects with HIV/HBV co-infection over 48 weeks (Clinical Trial A). Plus, a 12 week viral kinetic substudy comparing a subgroup of patients on Clinical Trial A is being conducted. (Substudy A1) Primary Objectives: * To compare the proportion of subjects with HBV DNA levels below the limit of detection (\<400 copies/ml) by week 48 in each treatment group Secondary Objectives: * To evaluate the emergence of HBV resistance at 48 weeks * To compare the proportion of patients with undetectable HBV DNA at weeks 12 and 24 in each treatment group * To compare the proportion of patients who achieve HBeAg and HBsAg seroconversion at weeks 12, 24 and 48 during the study * To compare changes in ALT from baseline and the rate of hepatic cytolysis (ALT\>5x ULN) * To compare suppression of HIV-1 RNA and changes in CD4/CD8 counts over 48 weeks * To compare the effect of therapy on histological changes in the liver and the presence of ccc-DNA Enrollment: * 24 patients in Clinical trial A (of whom 16 enter substudy A1). Clinical Trial A: * Patients with HIV/HBV co-infection who are naive to HIV/HBV therapy, have detectable HBV viraemia and are willing to start antiretroviral therapy. Inclusion Criteria: * Written informed consent * Documented HIV infection * Age 18 - 70 years * HBV DNA \> 106 copies/ml Randomization: * Arm 1: Zidovudine (AZT), emtricitabine (FTC), efavirenz (EFV) * Arm 2: Tenofovir (TDF), emtricitabine (FTC), efavirenz (EFV)