Effectiveness and Cost Effectiveness of Expanding Harm Reduction and Antiretroviral Therapy in a Mixed HIV Epidemic: A Modeling Analysis for Ukraine

A cost-effectiveness study by Sabina Alistar and colleagues evaluates the effectiveness and cost effectiveness of different levels of investment in methadone, ART, or both, in the mixed HIV epidemic in Ukraine

Comparative effectiveness and cost-effectiveness of antiretroviral therapy and pre-exposure prophylaxis for HIV prevention in South Africa

BACKGROUND: Antiretroviral therapy (ART) and oral pre-exposure prophylaxis (PrEP) are effective in reducing HIV transmission in heterosexual adults. The epidemiologic impact and cost-effectiveness of combined prevention approaches in resource-limited settings remain unclear. METHODS: We develop a dynamic mathematical model of the HIV epidemic in South Africa’s adult population. We assume ART reduces HIV transmission by 95% and PrEP by 60%. We model two ART strategies: scaling up access for those with CD4 counts ≤ 350 cells/μL (Guidelines) and for all identified HIV-infected individuals (Universal). PrEP strategies include use in the general population (General) and in high-risk individuals (Focused). We consider strategies where ART, PrEP, or both are scaled up to 100% of remaining eligible individuals yearly. We measure infections averted, quality-adjusted life-years (QALYs) gained and incremental cost-effectiveness ratios over 20 years. RESULTS: Scaling up ART to 50% of eligible individuals averts 1,513,000 infections over 20 years (Guidelines) and 3,591,000 infections (Universal). Universal ART is the most cost-effective strategy at any scale ($160-$220/QALY versus comparable scale Guidelines ART expansion). General PrEP is costly and provides limited benefits beyond ART scale-up ($7,680/QALY to add 100$12,640/QALY gained when added to 100% Universal ART). If feasible, Focused PrEP is cost saving or highly cost effective versus status quo and when added to ART strategies. CONCLUSIONS: Expanded ART coverage to individuals in early disease stages may be more cost-effective than current guidelines. PrEP can be cost-saving if delivered to individuals at increased risk of infection

Effectiveness and cost effectiveness of oral pre-exposure prophylaxis in a portfolio of prevention programs for injection drug users in mixed HIV epidemics.

BACKGROUND: Pre-exposure prophylaxis with oral antiretroviral treatment (oral PrEP) for HIV-uninfected injection drug users (IDUs) is potentially useful in controlling HIV epidemics with a significant injection drug use component. We estimated the effectiveness and cost effectiveness of strategies for using oral PrEP in various combinations with methadone maintenance treatment (MMT) and antiretroviral treatment (ART) in Ukraine, a representative case for mixed HIV epidemics. METHODS AND FINDINGS: We developed a dynamic compartmental model of the HIV epidemic in a population of non-IDUs, IDUs who inject opiates, and IDUs in MMT, adding an oral PrEP program (tenofovir/emtricitabine, 49% susceptibility reduction) for uninfected IDUs. We analyzed intervention portfolios consisting of oral PrEP (25% or 50% of uninfected IDUs), MMT (25% of IDUs), and ART (80% of all eligible patients). We measured health care costs, quality-adjusted life years (QALYs), HIV prevalence, HIV infections averted, and incremental cost effectiveness. A combination of PrEP for 50% of IDUs and MMT lowered HIV prevalence the most in both IDUs and the general population. ART combined with MMT and PrEP (50% access) averted the most infections (14,267). For a PrEP cost of $950, the most cost-effective strategy was MMT, at$520/QALY gained versus no intervention. The next most cost-effective strategy consisted of MMT and ART, costing $1,000/QALY gained compared to MMT alone. Further adding PrEP (25$1,700/QALY gained. PrEP alone became as cost effective as MMT at a cost of $650, and cost saving at$370 or less. CONCLUSIONS: Oral PrEP for IDUs can be part of an effective and cost-effective strategy to control HIV in regions where injection drug use is a significant driver of the epidemic. Where budgets are limited, focusing on MMT and ART access should be the priority, unless PrEP has low cost

HIV prevalence over 20 years for alternative strategies.

<p>Prevalence is shown for the status quo and alternative strategies of scaling up antiretroviral therapy (ART) to 80% of all eligible individuals, methadone maintenance treatment (MMT) for 25% of injection drug users (IDUs), and introducing oral pre-exposure prophylaxis (PrEP) for 25% or 50% of uninfected IDUs.</p

HIV infections averted over 20 years for alternative strategies.

<p>Infections averted are shown for alternative strategies of scaling up antiretroviral therapy (ART) to 80% of all eligible individuals, methadone maintenance treatment (MMT) to 25% of injection drug users (IDUs), and introducing oral pre-exposure prophylaxis (PrEP) for 25% or 50% of uninfected IDUs.</p

Cost effectiveness of alternative prevention and treatment strategies.

<p>Assumes annual PrEP cost of 950 (Figure 3a) and 450 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0086584#pone-0086584-g003" target="_blank">Figure 3b</a>). PrEP = oral pre-exposure prophylaxis for injection drug users; ART = antiretroviral therapy for 80% of eligible individuals; MMT = methadone maintenance treatment for 25% of IDUs; 25% PrEP = PrEP for 25% of uninfected IDUs; 50% PrEP = PrEP for 50% of uninfected IDUs.</p

Key parameter values, ranges, and sources.

<p>IDU = injection drug user, ART = antiretroviral therapy, MMT = methadone maintenance treatment, PrEP = pre-exposure prophylaxi.</p

Breakeven effectiveness for PrEP as a function of its annual cost.

<p>Effectiveness is measured as percentage reduction in chance of HIV infection acquisition. Assumes 25% of uninfected IDUs are enrolled in PrEP, in comparison to the status quo (no scale up of MMT or ART). Bottom line (triangles) shows minimum effectiveness for which PrEP would be considered highly cost effective (ICER = $7,400). Middle line (diamonds) shows minimum effectiveness for which PrEP would be as cost effective as MMT (ICER =$520). Top line (squares) shows minimum effectiveness for which PrEP would be cost saving (ICER = $0). PrEP = oral pre-exposure prophylaxis for injection drug users; ART = antiretroviral therapy; MMT = methadone maintenance therapy; ICER = incremental cost-effectiveness ratio.</p