Predicting the duration of antiviral treatment needed to suppress plasma HIV-1 RNA

Effective therapeutic interventions and clinical care of adults infected wi th HIV-1 require an understanding of factors that influence time of respons e to antiretroviral therapy. We have studied a cohort of 118 HIV-1-infected subjects naive to antiretroviral therapy and have correlated the time of r esponse to treatment with a series of virological and immunological measure s, including levels of viral load in blood and lymph node, percent of CD4 T cells in lymph nodes, and CD4 T-cell count in blood at study entry. Suppre ssion of viremia below the limit of detection, 50 HIV-1 RNA copies/mL of pl asma, served as a benchmark for a successful virological response. We emplo yed these correlations to predict the length of treatment required to attai n a virological response in each patient. Baseline plasma viremia emerged a s the factor most tightly correlated with the duration of treatment require d, allowing us to estimate the required time as a function of this one meas ure.