Abstract
Aim of the study was to determine predictors of the duration of antiretroviral treatment interruption in patients infected with HIV. This pilot prospective, openโlabel, multicenter trial comprised 62 HIVโseropositive subjects who decided voluntarily to interrupt therapy after two or more years of successful HAART. The primary endโpoint was the time to patients being free of therapy before reaching a CD4+ cell count โค350/ยตl. Fifteen of 62 patients remained in treatment interruption for more than 180 days. Patients restarting therapy had higher HIVโDNA levels (Pโ=โ0.05), were treated more frequently with NNRTIโdrugs (Pโ=โ0.02), had a shorter period of HAART (Pโ=โ0.046), and lower CD4+ cell counts after day 14 of interruption of treatment (Pโ=โ0.04). Multivariate regression analysis showed that less than 323 baseline proviral HIVโDNA cp/10^6^ PBMCs and more than 564 CD4 cells/ยตl at day 14 after interruption were associated independently with a reduced risk of restarting treatment (Pโ=โ0.041 and Pโ=โ0.012, respectively). A score based on CD4+ cell counts at nadir, at baseline, at week 2 of treatment interruption, and on baseline HIVโDNA values can identify patients with a prolonged period free safely of treatment. J. Med. Virol. 81:481โ487, 2009. ยฉ 2009 WileyโLiss, Inc.