Journal of acquired immune deficiency syndromes (1999) 2017 05 17() doi 10.1097/QAI.0000000000001452
Adequate antiretroviral exposure is crucial for virological suppression. We assessed the relationship between atazanavir hair levels with self-reported adherence, virological outcomes, and the effect of a home-based adherence intervention in HIV-infected adolescents failing 2-line antiretroviral treatment in Zimbabwe.
HIV-infected adolescents on atazanavir/ritonavir-based 2-line treatment for ≥6 months with viral load (VL) >1,000 copies/ml were randomised to either standard care (control) or standard care plus modified directly administered antiretroviral therapy (mDAART) (intervention). Questionnaires were administered; VL and hair samples were collected at baseline and after 90 days in each group. Viral suppression was defined as <1,000 copies/ml after follow-up. RESULTS
Fifty adolescents (10-18 years) were enrolled; 23(46%) were randomized to intervention and 27(54%) to control. Atazanavir hair concentration <2.35ng/mg (lower inter-quartile range for those with virological suppression) defined a cut-off below which most participants experienced virological failure. Male sex (p=0.03), virological suppression at follow-up (p=0.013), greater reduction in VL (p=0.006) and change in average self-reported adherence over the previous month (p=0.031) were associated with adequate (>2.35ng/mg) hair concentrations. Participants with virological failure were more likely to have sub-optimal atazanavir hair concentrations (RR=7.2, 95% CI=1-51, p=0.049). There were no differences in atazanavir hair concentration between the arms after follow-up.
A threshold of atazanavir concentrations in hair (2.35ng/mg), above which virological suppression was likely, was defined for adolescents failing 2 line atazanavir/ritonavir-based ART in Zimbabwe. Male sex and better self-reported adherence were associated with adequate atazanavir hair concentrations. Antiretroviral hair concentrations may serve as a useful clinical tool among adolescents.