OBJECTIVE HIV/hepatitis B virus (HBV) coinfection is common in Ghana, where first-line antiretroviral therapy (ART) comprises lamivudine with zidovudine or stavudine and nevirapine or efavirenz. Little is known about ART outcomes in the context of coinfection. This study evaluated outcomes of ART among HIV/HBV-coinfected Ghanaians, focusing on locally available parameters. METHODS An observational study comparing clinical and virological outcomes in HIV-infected individuals who were either hepatitis B surface antigen (HBsAg) positive or HBsAg negative was conducted over 36 months. Clinical events, hepatic transaminases, CD4 count and body mass index (BMI) were evaluated among 143 HBsAg-positive and 228 HBsAg-negative patients. In a random subset of HBsAg-positive patients, HBV-DNA levels and polymerase sequences were analysed. RESULTS Comparing HBsAg-positive and HBsAg-negative patients, 44/143 (30.8%) and 83/228 (36.4%) defaulted follow-up, 15/143 (10.5%) and 30/228 (13.2%) experienced a new clinical event, and 8/143 (5.6%) and 11/228 (4.8%) discontinued their initial regimen, respectively. Transaminase levels were higher in HBsAg-positive patients, although elevations were low grade. HBV coinfection was associated with an adjusted 2.04 (95% CI 0.59-3.49) cells/mm(3)/month smaller CD4 cell increase; there was no significant effect on BMI changes. After a median of 9 months of ART, 64/66 (97.0%) patients showed detectable HBV-DNA (median 3.3 log(10) IU/mL; IQR 2.6-6.2); 12/53 (22.6%) of these showed lamivudine-associated resistance mutations. CONCLUSIONS HIV/HBV-coinfected Ghanaians tolerated first-line ART well, but experienced blunted CD4 cell responses. There was evidence of ongoing HBV replication, mild but persistent transaminase elevations and emerging lamivudine resistance in a proportion of treated patients, indicating the potential for progressive liver damage.