Background Universal testing and treatment (UTT) is a potential strategy to reduce HIV incidence, yet prior trial results are inconsistent. We report results from HPTN 071 (PopART), the largest HIV prevention trial to date. Methods In this community-randomized trial (2013-18), 21 communities in Zambia and South Africa were randomized to Arm A (PopART intervention, universal antiretroviral therapy [ART]), Arm B (PopART intervention, ART per local guidelines), and Arm C (standard-of-care). The PopART intervention included home-based HIV-testing delivered by community workers who supported linkage-to-care, ART adherence, and other services. The primary outcome, HIV incidence between months 12-36, was measured in a Population Cohort (PC) of ~2,000 randomly-sampled adults/community aged 18-44y. Viral suppression (VS, <400 copies HIV RNA/ml) was measured in all HIV-positive PC participants at 24m. Results The PC included 48,301 participants. Baseline HIV prevalence was similar across study arms (21%-22%). Between months 12-36, 553 incident HIV infections were observed over 39,702 person-years (py; 1.4/100py; women: 1.7/100py; men: 0.8/100py). Adjusted rate-ratios were A vs. C: 0.93 (95%CI: 0.74-1.18, p=0.51); B vs. C: 0.70 (95%CI: 0.55-0.88, p=0.006). At 24m, VS was 71.9% in Arm A; 67.5% in Arm B; and 60.2% in Arm C. ART coverage after 36m was 81% in Arm A and 80% in Arm B. Conclusions The PopART intervention with ART per local guidelines reduced HIV incidence by 30%. The lack of effect with universal ART was surprising and inconsistent with VS data. This study provides evidence that UTT can reduce HIV incidence at population level. Trial registration ClinicalTrials.gov NCT01900977

BackgroundEffective interventions to reduce HIV incidence in sub-Saharan Africa are urgently needed. Mathematical modelling and the HIV Prevention Trials Network (HPTN) 052 trial results suggest that universal HIV testing combined with immediate antiretroviral treatment (ART) should substantially reduce incidence and may eliminate HIV as a public health problem. We describe the rationale and design of a trial to evaluate this hypothesis.Methods/DesignA rigorously-designed trial of universal testing and treatment (UTT) interventions is needed because: i) it is unknown whether these interventions can be delivered to scale with adequate uptake; ii) there are many uncertainties in the models such that the population-level impact of these interventions is unknown; and ii) there are potential adverse effects including sexual risk disinhibition, HIV-related stigma, over-burdening of health systems, poor adherence, toxicity, and drug resistance.In the HPTN 071 (PopART) trial, 21 communities in Zambia and South Africa (total population 1.2 m) will be randomly allocated to three arms. Arm A will receive the full PopART combination HIV prevention package including annual home-based HIV testing, promotion of medical male circumcision for HIV-negative men, and offer of immediate ART for those testing HIV-positive; Arm B will receive the full package except that ART initiation will follow current national guidelines; Arm C will receive standard of care. A Population Cohort of 2,500 adults will be randomly selected in each community and followed for 3 years to measure the primary outcome of HIV incidence. Based on model projections, the trial will be well-powered to detect predicted effects on HIV incidence and secondary outcomes.DiscussionTrial results, combined with modelling and cost data, will provide short-term and long-term estimates of cost-effectiveness of UTT interventions. Importantly, the three-arm design will enable assessment of how much could be achieved by optimal delivery of current policies and the costs and benefits of extending this to UTT.Trial registrationClinicalTrials.gov NCT01900977.

Oral preexposure prophylaxis (PrEP) trials report disparate efficacy attributed to variable adherence. HPTN 066 was conducted to establish objective, quantitative benchmarks for discrete, regular levels of adherence using directly observed dosing of tenofovir (TFV) disoproxil fumarate (TDF)/emtricitabine (FTC). Healthy, HIV-uninfected men and women were randomized to one of four oral regimens of fixed-dose TDF 300 mg/FTC 200 mg tablet for 5 weeks with all doses observed: one tablet weekly (one/week), one tablet twice weekly (two/week), two tablets twice weekly (four/week), or one tablet daily (seven/week). Trough serum TFV and FTC, peripheral blood mononuclear cell (PBMC), and CD4(+) TFV-diphosphate (TFV-DP) and FTC-triphosphate (FTC-TP) concentrations were determined throughout dosing and 2 weeks after the last dose. Rectosigmoidal, semen, and cervicovaginal samples were collected for drug assessment at end of dosing and 2 weeks later in a subset of participants. The 49 enrolled participants tolerated the regimens well. All regimens achieved steady-state concentrations by the second dose for serum TFV/FTC and by 7 days for PBMC TFV-DP/FTC-TP. Steady-state median TFV-DP predose concentrations demonstrated dose proportionality: one/week 1.6 fmol/10(6) PBMCs, two/week 9.1, four/week 18.8, seven/week, 36.3. Further, TFV-DP was consistently quantifiable 2 weeks after the last dose for the ≥4/week regimens. Adherence benchmarks were identified using receiver operating characteristic curves, which had areas under the curve ≥0.93 for all analytes in serum and PBMCs. Intersubject and intrasubject coefficients of variation (%CV) ranged from 33% to 63% and 14% to 34%, respectively, for all analytes in serum and PBMCs. Steady-state PBMC TFV-DP was established earlier and at lower concentrations than predicted and was the only analyte demonstrating predose concentration dose proportionality. Steady-state daily dosing serum TFV and PBMC TFV-DP was consistent with highly effective PrEP clinical trials. HPTN 066 provides adherence benchmarks for oral TFV/FTC regimens to assist interpreting study outcomes.

BackgroundThe HPTN 052 trial confirmed that antiretroviral therapy (ART) can nearly eliminate HIV transmission from successfully treated HIV-infected individuals within couples. Here, we present the mathematical modeling used to inform the design and monitoring of a new trial aiming to test whether widespread provision of ART is feasible and can substantially reduce population-level HIV incidence.Methods and FindingsThe HPTN 071 (PopART) trial is a three-arm cluster-randomized trial of 21 large population clusters in Zambia and South Africa, starting in 2013. A combination prevention package including home-based voluntary testing and counseling, and ART for HIV positive individuals, will be delivered in arms A and B, with ART offered universally in arm A and according to national guidelines in arm B. Arm C will be the control arm. The primary endpoint is the cumulative three-year HIV incidence.We developed a mathematical model of heterosexual HIV transmission, informed by recent data on HIV-1 natural history. We focused on realistically modeling the intervention package. Parameters were calibrated to data previously collected in these communities and national surveillance data.We predict that, if targets are reached, HIV incidence over three years will drop by >60% in arm A and >25% in arm B, relative to arm C. The considerable uncertainty in the predicted reduction in incidence justifies the need for a trial. The main drivers of this uncertainty are possible community-level behavioral changes associated with the intervention, uptake of testing and treatment, as well as ART retention and adherence.ConclusionsThe HPTN 071 (PopART) trial intervention could reduce HIV population-level incidence by >60% over three years. This intervention could serve as a paradigm for national or supra-national implementation. Our analysis highlights the role mathematical modeling can play in trial development and monitoring, and more widely in evaluating the impact of treatment as prevention.