Major clinical outcomes in antiretroviral therapy (ART)-naive participants and in those not receiving ART at baseline in the SMART study

Abstract

Background: The SMART study randomized 5,472 human immunodeficiency virus (HIV)-infected patients with CD4+ cell counts >350 cells/microL to intermittent antiretroviral therapy (ART; the drug conservation [DC] group) versus continuous ART (the viral suppression [VS] group). In the DC group, participants started ART when the CD4+ cell count was <250 cells/microL. Clinical outcomes in participants not receiving ART at entry inform the early use of ART.

Methods: Patients who were either ART naive (n=249) or who had not been receiving ART for >or= 6 months (n=228) were analyzed. The following clinical outcomes were assessed: (i) opportunistic disease (OD) or death from any cause (OD/death); (ii) OD (fatal or nonfatal); (iii) serious non-AIDS events (cardiovascular, renal, and hepatic disease plus non-AIDS-defining cancers) and non-OD deaths; and (iv) the composite of outcomes (ii) and (iii).

Results: A total of 477 participants (228 in the DC group and 249 in the VS group) were followed (mean, 18 months). For outcome (iv), 21 and 6 events occurred in the DC (7 in ART-naive participants and 14 in those who had not received ART for >or= 6 months) and VS (2 in ART-naive participants and 4 in those who had not received ART for 6 months) groups, respectively. Hazard ratios for DC vs. VS by outcome category were as follows: outcome (i), 3.47 (95% confidence interval [CI], 1.26-9.56; p=.02); outcome (ii), 3.26 (95% CI, 1.04-10.25; p=.04); outcome (iii), 7.02 (95% CI, 1.57-31.38; p=.01); and outcome (iv), 4.19 (95% CI, 1.69-10.39; p=.002 ).

Conclusions: Initiation of ART at CD4+ cell counts >350 cells/microL compared with <250 cells/microL may reduce both OD and serious non-AIDS events. These findings require validation in a large, randomized clinical trial.

Trial registration: ClinicalTrials.gov NCT00027352.