Long-term hepatitis B virus surface antigen decay in HIV-1/hepatitis B virus-coinfected adults initiating a tenofovir-containing regimen.

Hepatitis B virus (HBV) surface antigen (HBsAg) decay was explored in HIV-1- and HBV-coinfected patients beginning antiretroviral (ARV) therapy containing tenofovir disoproxil fumarate (TDF). The mean HBsAg decay was 0.38 log(10) IU/ml/year (95% confidence interval [CI], 0.71 to 0.05) in 18 patients with sustained plasma HIV-1 RNA suppression and 0.15 log(10) IU/ml/year (0.21 to 0.09) in 12 patients experiencing HIV-1 virologic failure due to suboptimal adherence to ARV (P = 0.17). We estimated that six of these 18 patients will attain HBsAg values below 10 IU/ml after 10 years of treatment.