Uptake and virological outcomes of single- versus multi-tablet antiretroviral regimens among treatment-naïve youth in the HIV Research Network.

Objectives Several single-tablet regimens (STRs) are now available and are recommended for first-line antiretroviral therapy (ART); however, STR use for youth with HIV (YHIV) has not been systematically studied. We examined the characteristics associated with initiation of STRs versus multi-tablet regimens (MTRs) and the virological outcomes for youth with nonperinatally acquired HIV (nPHIV). Methods A retrospective cohort study of nPHIV youth aged 13-24 years initiating ART between 2006 and 2014 at 18 US HIV clinical sites in the HIV Research Network was performed. The outcomes measured were initiation of STRs versus MTRs, virological suppression (VS) at 12 months, and time to VS. Demographic and clinical factors associated with initiation of STR versus MTR ART and VS (mL) at 12 months after initiation were assessed using multivariable logistic regression. Cox proportional hazards regression was used to assess VS within the first year. Results Of 987 youth, 67% initiated STRs. Of the 589 who had viral load data at 1 year, 84% of those on STRs versus 67% of those on MTRs achieved VS (P < 0.01). VS was associated with STR use [adjusted odds ratio (AOR) 1.61; 95% confidence interval (CI) 1.01-2.58], white (AOR 2.41; 95% CI 1.13-5.13) or Hispanic (AOR 2.38; 95% CI 1.32-4.27) race/ethnicity, and baseline CD4 count 351-500 cells/mu L (AOR 1.94; 95% CI 1.18-3.19) and > 500 cells/mu L (AOR 1.76; 95% CI 1.0-3.10). STR use was not associated with a shorter time to VS compared with MTR use [hazard ratio (HR) 1.07; 95% CI 0.90-1.28]. Conclusions Use of STR was associated with a greater likelihood of sustained VS 12 months after ART initiation in YHIV.