Following treatment of hepatitis B virus (HBV) infection with
nucleos(t)ide reverse transcriptase inhibitors (NRTIs), there is
a biphasic clearance of HBV, similar to that seen following
treatment of human immunodeficiency virus-1 (HIV-1) and
hepatitis C virus. Little is known about the impact of
combination NRTIs and HIV-1 coinfection on HBV viral kinetic
parameters following the initiation of HBV-active highly active
antiretroviral therapy (HAART). HIV-1–HBV coinfected patients (n
= 21) were enrolled in a viral kinetics substudy of the
Tenofovir in HIV-1–HBV Coinfection study (TICO). TICO was a
randomized (1:1:1) trial of tenofovir disoproxil fumarate (TDF,
300 mg) versus lamivudine (LMV, 300 mg) versus TDF/LMV within an
efavirenz based HAART regimen initiated in HIV-1-HBV coinfected
antiretroviral naïve individuals in Thailand. HBV DNA was
measured frequently over the first 56 days. To fit the viral
load data, we used a model of HBV kinetics that allows the
estimation of treatment effectiveness, viral clea