Initiating
combination antiretroviral therapy (ART) during acute
HIV infection has been correlated with decreased viral set point and improved lymphocyte function. However, the long term effects of single-agent
therapy administered only during the acute stage of
infection (interrupted treatment) remain largely uncharacterized. In this study we provide longitudinal data using the feline immunodeficiency virus (FIV) model for
HIV infection. Infected cats were treated with a prophylactic single-agent
therapy,
Fozivudine tidoxil (FZD), for six weeks, starting one day before
infection. The initial acute
infection study, reported elsewhere, demonstrated a decrease in plasma- and cell-associated
viremia at two weeks post-
infection (PI) in FZD-treated cats as compared to placebo-treated cats. We hypothesized that this early alteration in plasma- and cell-associated
viremia would alter the virus set point and ultimately affect the outcome of
chronic infection. Here we provide data at one, two and three years PI for plasma- and/or cell-associated
viremia, total lymphocyte counts and CD4:CD8 ratios. There was no difference in
viremia or cell counts between treated and nontreated groups at all time points tested. Contrary to our hypothesis, these results suggest that treatment with a single agent anti-retroviral
drug during acute
lentivirus infection does not significantly alter viral load and immune function during the chronic, asymptomatic stage of
infection.