Cost and cost-effectiveness of a universal HIV testing and treatment intervention in Zambia and South Africa: evidence and projections from the HPTN 071 (PopART) trial

Abstract

Background: The HPTN 071 (PopART) trial showed that a combination HIV prevention package including universal HIV testing and treatment (UTT) reduced population-level incidence of HIV compared with standard care. However, evidence is scarce on the costs and cost-effectiveness of such an intervention.

Methods: Using an individual-based model, we simulated the PopART intervention and standard care with antiretroviral therapy (ART) provided according to national guidelines for the 21 trial communities in Zambia and South Africa (for all individuals aged >14 years), with model parameters and primary cost data collected during the PopART trial and from published sources. Two intervention scenarios were modelled: annual rounds of PopART from 2014 to 2030 (PopART 2014-30; as the UNAIDS Fast-Track target year) and three rounds of PopART throughout the trial intervention period (PopART 2014-17). For each country, we calculated incremental cost-effectiveness ratios (ICERs) as the cost per disability-adjusted life-year (DALY) and cost per HIV infection averted. Cost-effectiveness acceptability curves were used to indicate the probability of PopART being cost-effective compared with standard care at different thresholds of cost per DALY averted. We also assessed budget impact by projecting undiscounted costs of the intervention compared with standard care up to 2030.

Findings: During 2014-17, the mean cost per person per year of delivering home-based HIV counselling and testing, linkage to care, promotion of ART adherence, and voluntary medical male circumcision via community HIV care providers for the simulated population was US$6·53 (SD 0·29) in Zambia and US$7·93 (0·16) in South Africa. In the PopART 2014-30 scenario, median ICERs for PopART delivered annually until 2030 were $2111 (95% credible interval [CrI] 1827-2462) per HIV infection averted in Zambia and $3248 (2472-3963) per HIV infection averted in South Africa; and $593 (95% CrI 526-674) per DALY averted in Zambia and $645 (538-757) per DALY averted in South Africa. In the PopART 2014-17 scenario, PopART averted one infection at a cost of $1318 (1098-1591) in Zambia and $2236 (1601-2916) in South Africa, and averted one DALY at $258 (225-298) in Zambia and $326 (266-391) in South Africa, when outcomes were projected until 2030. The intervention had almost 100% probability of being cost-effective at thresholds greater than $700 per DALY averted in Zambia, and greater than $800 per DALY averted in South Africa, in the PopART 2014-30 scenario. Incremental programme costs for annual rounds until 2030 were $46·12 million (for a mean of 341 323 people) in Zambia and $30·24 million (for a mean of 165 852 people) in South Africa.

Interpretation: Combination prevention with universal home-based testing can be delivered at low annual cost per person but accumulates to a considerable amount when scaled for a growing population. Combination prevention including UTT is cost-effective at thresholds greater than $800 per DALY averted and can be an efficient strategy to reduce HIV incidence in high-prevalence settings.

Funding: US National Institutes of Health, President's Emergency Plan for AIDS Relief, International Initiative for Impact Evaluation, Bill & Melinda Gates Foundation.

Figure 1

Health effects of the PopART intervention under different scenarios Box plots show the median (IQR) for 1000 retained simulations of new HIV infections and DALYs averted in Zambia and South Africa in 2014–30. Outliers were calculated as datapoints greater or less than 1·5× the IQR from upper and lower IQR values. (A and C) PopART 2014–30 scenario: PopART intervention implemented in annual rounds between 2014 and 2030. (B and D) PopART 2014–17 scenario: PopART intervention implemented in three annual rounds between 2014 and 2017 and then discontinued up to 2030. DALY=disability-adjusted life-year. The simulated mean annual population covered in 2014–30 (accounting for population growth) was 341 323 in Zambia and 165 852 in South Africa.

Figure 2

Cost-effectiveness planes Incremental cost-effectiveness ratios for PopART 2014–30 and PopART 2014–17 scenarios compared with standard care. Graphs show simulations, with median cost plotted against median effect. (A and C) Incremental costs and HIV infections or DALYs averted in the PopART 2014–30 scenario. (B and D) Incremental costs and HIV infections or DALYs averted in the PopART 2014–17 scenario. DALY=disability-adjusted life-year.

Figure 3

Cost-effectiveness acceptability curves by cost per DALY thresholds Cost-effectiveness acceptability curves represent the probability that the intervention is cost-effective across the simulations at specific thresholds of cost per DALY averted. DALY=disability-adjusted life-year.

Figure 4

Budget impact of the PopART 2014–30 scenario Projected undiscounted annual cost (all cost components) in intervention communities and standard care (counterfactual) communities in the PopART 2014–30 scenario in Zambia (A) and South Africa (B). Projected undiscounted costs totalled for the period 2014–30 by cost component in Zambia (C) and South Africa (D). CHiP=community HIV care provider. ART=antiretroviral therapy.