Cost-effectiveness of HIV treatment as prevention in serodiscordant couples

Longitudinal evolution of the HIV effective reproduction number following sequential expansion of treatment as prevention and pre-exposure prophylaxis in British Columbia, Canada: a population-level programme evaluation

BACKGROUND

Treatment as prevention and pre-exposure prophylaxis (PrEP) are key strategies in the control of HIV/AIDS. We aimed to characterise the longitudinal effects of antiretroviral therapy (ART), followed by treatment as prevention and the addition of PrEP, on the HIV effective reproduction number (Re) in British Columbia, Canada.

METHODS

This population-level programme evaluation used data from the Drug Treatment Program of the British Columbia Centre for Excellence in HIV/AIDS (Vancouver, British Columbia, Canada). We also used estimates of HIV incidence and prevalence from the Public Health Agency of Canada, data on the number of new HIV diagnoses per year from the British Columbia Centre for Disease Control, and mortality data from the British Columbia Vital Statistics Agency. Data were obtained from 1985 until 2022, depending on the database source. Outcomes were the annual HIV prevalence, HIV incidence, number of new HIV diagnoses, number of people living with HIV on ART, HIV/AIDS-related and all-cause mortality rates, the HIV incidence-to-all-cause-mortality ratio, and Re. We calculated the modified effective reproduction number (Rme) using two thresholds of viral suppression and compared these values with Re.

FINDINGS

We found a 95% decline in HIV/AIDS-related mortality and a 91% decrease in HIV incidence over the study period. The Re progressively declined from 1996 to 2022; however, from 1996 to 2017, Rme remained stable (>1) when calculated for people living with HIV with unsuppressed viraemia, suggesting that treatment as prevention reduces HIV incidence by decreasing the pool of individuals who are potentially able to transmit the virus. From 2018 to 2022, a decline in the estimated Re and Rme (<1) was observed regardless of whether we considered all people living with HIV or only those who were virologically unsuppressed. This finding suggests that PrEP decreases HIV incidence by reducing the number of susceptible individuals in the community, independently of viral suppression.

INTERPRETATION

Our results show the synergy between generalised treatment as prevention and targeted PrEP in terms of decreasing HIV incidence. These findings support the incorporation of longitudinal monitoring of Re at a programmatic level to identify opportunities for the optimisation of treatment-as-prevention and PrEP programmes.

FUNDING

British Columbia Ministry of Health, Health Canada, Public Health Agency of Canada, Vancouver Coastal Health, Vancouver General Hospital Foundation, Genome British Columbia, and the Canadian Institutes of Health Research.

The Success of Serious Games and Gamified Systems in HIV Prevention and Care: Scoping Review

BACKGROUND

AIDS, which is caused by HIV, has long been one of the most significant global public health issues. Since the beginning of the HIV epidemic, various types of nonelectronic communication tools have been commonly used in HIV/AIDS prevention and care, but studies that apply the potential of electronic games are still limited.

OBJECTIVE

We aimed to identify, compare, and describe serious games and gamified systems currently used in HIV/AIDS prevention and care that were studied over a specific period of time.

METHODS

A scoping review was conducted into serious games and gamified systems used in HIV prevention and care in various well-known digital libraries from January 2010 to July 2021.

RESULTS

After identifying research papers and completing the article selection process, 49 of the 496 publications met the inclusion criteria and were examined. A total of 32 articles described 22 different serious games, while 17 articles described 13 gamified systems for HIV prevention and care.

CONCLUSIONS

Most of the studies described in the publications were conducted in the United States, while only a few studies were performed in sub-Saharan African countries, which have the highest global HIV/AIDS infection rates. Regarding the development platform, the vast majority of HIV/AIDS gaming systems were typically deployed on mobile devices. This study demonstrates the effectiveness of using serious games and gamified systems. Both can improve the efficacy of HIV/AIDS prevention strategies, particularly those that encourage behavior change.

The Value-of-Information and Value-of-Implementation from Clinical Trials of Diagnostic Tests for HIV-Associated Tuberculosis: A Modeling Analysis

Objectives. Conventional value-of-information (VOI) analysis assumes complete uptake of an optimal decision. We employed an extended framework that includes value-of-implementation (VOM)-the benefit of encouraging adoption of an optimal strategy-and estimated how future trials of diagnostic tests for HIV-associated tuberculosis could improve public health decision making and clinical and economic outcomes. Methods. We evaluated the clinical outcomes and costs, given current information, of 3 tuberculosis screening strategies among hospitalized people with HIV in South Africa: sputum Xpert (Xpert), sputum Xpert plus urine AlereLAM (Xpert+AlereLAM), and sputum Xpert plus the newer, more sensitive, and costlier urine FujiLAM (Xpert+FujiLAM). We projected the incremental net monetary benefit (INMB) of decision making based on results of a trial comparing mortality with each strategy, rather than decision making based solely on current knowledge of FujiLAM's improved diagnostic performance. We used a validated microsimulation to estimate VOI (the INMB of reducing parameter uncertainty before decision making) and VOM (the INMB of encouraging adoption of an optimal strategy). Results. With current information, adopting Xpert+FujiLAM yields 0.4 additional life-years/person compared with current practices (assumed 50% Xpert and 50% Xpert+AlereLAM). While the decision to adopt this optimal strategy is unaffected by information from the clinical trial (VOI = $ 0 at $3,000/year-of-life saved willingness-to-pay threshold), there is value in scaling up implementation of Xpert+FujiLAM, which results in an INMB (representing VOM) of $650 million over 5 y. Conclusions. Conventional VOI methods account for the value of switching to a new optimal strategy based on trial data but fail to account for the persuasive value of trials in increasing uptake of the optimal strategy. Evaluation of trials should include a focus on their value in reducing barriers to implementation.

Highlights

In conventional VOI analysis, it is assumed that the optimal decision will always be adopted even without a trial. This can potentially lead to an underestimation of the value of trials when adoption requires new clinical trial evidence. To capture the influence that a trial may have on decision makers' willingness to adopt the optimal decision, we also consider value-of-implementation (VOM), a metric quantifying the benefit of new study information in promoting wider adoption of the optimal strategy. The overall value-of-a-trial (VOT) includes both VOI and VOM.Our model-based analysis suggests that the information obtained from a trial of screening strategies for HIV-associated tuberculosis in South Africa would have no value, when measured using traditional methods of VOI assessment. A novel strategy, which includes the urine FujiLAM test, is optimal from a health economic standpoint but is underutilized. A trial would reduce uncertainties around downstream health outcomes but likely would not change the optimal decision. The high VOT (nearly $700 million over 5 y) lies solely in promoting uptake of FujiLAM, represented as VOM.Our results highlight the importance of employing a more comprehensive approach for evaluating prospective trials, as conventional VOI methods can vastly underestimate their value. Trialists and funders can and should assess the VOT metric instead when considering trial designs and costs. If VOI is low, the VOM and cost of a trial can be compared with the benefits and costs of other outreach programs to determine the most cost-effective way to improve uptake.

A Growing Number of Men Who Have Sex With Men Aging With HIV (20212031): A Comparison of Two Microsimulation Models

BACKGROUND

Men who have sex with men (MSM) on antiretroviral therapy (ART) are at risk for multimorbidity as life expectancy increases. Simulation models can project population sizes and age distributions to assist with health policy planning.

METHODS

We populated the CEPAC-US model with CDC data to project the HIV epidemic among MSM in the United States. The PEARL model was predominantly informed by NA-ACCORD data (20092017). We compared projected population sizes and age distributions of MSM receiving ART (20212031) and investigated how parameters and assumptions affected results.

RESULTS

We projected an aging and increasing population of MSM on ART: CEPAC-US, mean age 48.6 (SD 13.7) years in 2021 versus 53.9 (SD 15.0) years in 2031; PEARL, 46.7 (SD 13.2) years versus 49.2 (SD 14.6) years. We projected 548 800 MSM on ART (147 020 65 years) in 2031 (CEPAC-US) and 599 410 (113 400 65 years) (PEARL). Compared with PEARL, CEPAC-US projected a smaller population of MSM on ART by 2031 and a slower increase in population size, driven by higher estimates of disengagement in care and mortality.

CONCLUSIONS

Findings from two structurally distinct microsimulation models suggest that the MSM population receiving ART in the United States will increase and age over the next decade. Subgroup-specific data regarding engagement in care and mortality can improve projections and inform health care policy planning.

Nutritional Supplementation Would Be Cost-Effective for Reducing Tuberculosis Incidence and Mortality in India: The Ration Optimization to Impede Tuberculosis (ROTI-TB) Model

BACKGROUND

Undernutrition is the leading cause of tuberculosis (TB) in India and is associated with increased TB mortality. Undernutrition also decreases quality of life and economic productivity.

METHODS

We assessed the cost-effectiveness of providing augmented rations to undernourished Indians through the government's Targeted Public Distribution System (TPDS). We used Markov state transition models to simulate disease progression and mortality among undernourished individuals in 3 groups: general population, household contacts (HHCs) of people living with TB, and persons living with human immunodeficiency virus (HIV). The models calculate costs and outcomes (TB cases, TB deaths, and disability-adjusted life years [DALYs]) associated with a 2600 kcal/day diet for adults with body mass index (BMI) of 16-18.4 kg/m2 until they attain a BMI of 20 kg/m2 compared to a status quo scenario wherein TPDS rations are unchanged. We employed deterministic and probabilistic sensitivity analyses to test result robustness.

RESULTS

Over 5 years, augmented rations could avert 81% of TB cases and 88% of TB deaths among currently undernourished Indians. Correspondingly, this intervention could forestall 78% and 48% of TB cases and prevent 88% and 70% of deaths among undernourished HHCs and persons with HIV, respectively. Augmented rations resulted in 10-fold higher resolution of undernutrition and were highly cost-effective with (incremental cost-effectiveness ratio [ICER] of $470/DALY averted). ICER was lower for HHCs ($360/DALY averted) and the HIV population ($250/DALY averted).

CONCLUSIONS

A robust nutritional intervention would be highly cost-effective in reducing TB incidence and mortality while reducing chronic undernutrition in India.

Evaluation of four chemotherapy regimens for treatment of advanced AIDS-associated Kaposi sarcoma in Kenya: a cost-effectiveness analysis

BACKGROUND

The most effective treatment for advanced AIDS-associated Kaposi sarcoma is paclitaxel or pegylated liposomal doxorubicin (PLD); neither is routinely used in sub-Saharan Africa due to limited availability and high cost. We examined the clinical impact, costs, and cost-effectiveness of paclitaxel or PLD in Kenya, compared with etoposide or bleomycin-vincristine.

METHODS

In this study, we use the Cost-Effectiveness of Preventing AIDS Complications (CEPAC)-International Model to project clinical outcomes and costs among people living with HIV and advanced Kaposi sarcoma on antiretroviral therapy. We compared four different treatment strategies: etoposide, bleomycin-vincristine, paclitaxel, or PLD. We derived cohort characteristics and costs from the Kenyan Academic Model for Providing Access to Healthcare network, and adverse events, efficacy, and mortality from clinical trials. We projected model outcomes over a lifetime and included life expectancy, per-person lifetime costs, and incremental cost-effectiveness ratios (ICERs). We conducted budget impact analysis for 5-year total costs and did deterministic and probabilistic sensitivity analyses to evaluate the effect of uncertainty in input parameters.

FINDINGS

We found that paclitaxel would be more effective than bleomycin-vincristine and would increase life expectancy by 4·2 years per person. PLD would further increase life expectancy by 0·6 years per person. Paclitaxel would be the most cost-effective strategy (ICER US$380 per year-of-life-saved compared with bleomycin-vincristine) and would remain cost-effective across a range of scenarios. PLD would be cost-effective compared with paclitaxel if its price were reduced to $100 per cycle (base case $180 per cycle). Implementing paclitaxel instead of bleomycin-vincristine would save approximately 6400 life-years and would increase the overall 5-year Kenyan health-care costs by $3·7 million; increased costs would be primarily related to ongoing HIV care given improved survival.

INTERPRETATION

Paclitaxel would substantially increase life expectancy and be cost-effective compared with bleomycin-vincristine for advanced AIDS-associated Kaposi sarcoma in Kenya and should be the standard of care. PLD would further improve survival and be cost-effective with a 44% price reduction.

FUNDING

US National Institutes of Health and Massachusetts General Hospital.

TRANSLATION

For the Swahili translation of the abstract see Supplementary Materials section.

Health Impact and Cost-Effectiveness of HIV Testing, Linkage, and Early Antiretroviral Treatment in the Botswana Combination Prevention Project

BACKGROUND

The Botswana Combination Prevention Project tested the impact of combination prevention (CP) on HIV incidence in a community-randomized trial. Each trial arm had ∼55,000 people, 26% HIV prevalence, and 72% baseline ART coverage. Results showed intensive testing and linkage campaigns, expanded antiretroviral treatment (ART), and voluntary male medical circumcision referrals increased coverage and decreased incidence over ∼29 months of follow-up. We projected lifetime clinical impact and cost-effectiveness of CP in this population.

SETTING

Rural and periurban communities in Botswana.

METHODS

We used the Cost-Effectiveness of Preventing AIDS Complications model to estimate lifetime health impact and cost of (1) earlier ART initiation and (2) averting an HIV infection, which we applied to incremental ART initiations and averted infections calculated from trial data. We determined the incremental cost-effectiveness ratio [US$/quality-adjusted life-years (QALY)] for CP vs. standard of care.

RESULTS

In CP, 1418 additional people with HIV initiated ART and an additional 304 infections were averted. For each additional person started on ART, life expectancy increased 0.90 QALYs and care costs increased by $869. For each infection averted, life expectancy increased 2.43 QALYs with $9200 in care costs saved. With CP, an additional $1.7 million were spent on prevention and $1.2 million on earlier treatment. These costs were mostly offset by decreased care costs from averted infections, resulting in an incremental cost-effectiveness ratio of $79 per QALY.

CONCLUSIONS

Enhanced HIV testing, linkage, and early ART initiation improve life expectancy, reduce transmission, and can be cost-effective or cost-saving in settings like Botswana.

Development and validation of the age-associated dementia policy (AgeD-Pol) computer simulation model in the USA and Europe

OBJECTIVE

To develop and validate a novel, microsimulation model that accounts for the prevalence and incidence of age-associated dementias (AAD), disease progression and associated mortality.

DESIGN, DATA SOURCES AND OUTCOME MEASURES

We developed the AAD policy (AgeD-Pol) model, a microsimulation model to simulate the natural history, morbidity and mortality associated with AAD. We populated the model with age-stratified and sex-stratified data on AAD prevalence, AAD incidence and mortality among people with AAD. We first performed internal validation using data from the Adult Changes in Thought (ACT) cohort study. We then performed external validation of the model using data from the Framingham Heart Study, the Rotterdam Study and Kaiser Permanente Northern California (KPNC). We compared model-projected AAD cumulative incidence and mortality with published cohort data using mean absolute percentage error (MAPE) and root-mean-square error (RMSE).

RESULTS

In internal validation, the AgeD-Pol model provided a good fit to the ACT cohort for cumulative AAD incidence, 10.4% (MAPE, 0.2%) and survival, 66.5% (MAPE, 8.8%), after 16 years of follow-up among those initially aged 65-69 years. In the external validations, the model-projected lifetime cumulative incidence of AAD was 30.5%-32.4% (females) and 16.7%-23.0% (males), using data from the Framingham and Rotterdam cohorts, and AAD cumulative incidence was 21.5% over 14 years using KPNC data. Model projections demonstrated a good fit to all three cohorts (MAPE, 0.9%-9.0%). Similarly, model-projected survival provided good fit to the Rotterdam (RMSE, 1.9-3.6 among those with and without AAD) and KPNC cohorts (RMSE, 7.6-18.0 among those with AAD).

CONCLUSIONS

The AgeD-Pol model performed well when validated to published data for AAD cumulative incidence and mortality and provides a useful tool to project the AAD disease burden for health systems planning in the USA.

Using Microsimulation Modeling to Inform EHE Implementation Strategies in Los Angeles County

BACKGROUND

Pre-exposure prophylaxis (PrEP) is essential to ending HIV. Yet, uptake remains uneven across racial and ethnic groups. We aimed to estimate the impacts of alternative PrEP implementation strategies in Los Angeles County.

SETTING

Men who have sex with men, residing in Los Angeles County.

METHODS

We developed a microsimulation model of HIV transmission, with inputs from key local stakeholders. With this model, we estimated the 15-year (2021-2035) health and racial and ethnic equity impacts of 3 PrEP implementation strategies involving coverage with 9000 additional PrEP units annually, above the Status-quo coverage level. Strategies included PrEP allocation equally (strategy 1), proportionally to HIV prevalence (strategy 2), and proportionally to HIV diagnosis rates (strategy 3), across racial and ethnic groups. We measured the degree of relative equalities in the distribution of the health impacts using the Gini index (G) which ranges from 0 (perfect equality, with all individuals across all groups receiving equal health benefits) to 1 (total inequality).

RESULTS

HIV prevalence was 21.3% in 2021 [Black (BMSM), 31.1%; Latino (LMSM), 18.3%, and White (WMSM), 20.7%] with relatively equal to reasonable distribution across groups (G, 0.28; 95% confidence interval [CI], 0.26 to 0.34). During 2021-2035, cumulative incident infections were highest under Status-quo (n = 24,584) and lowest under strategy 3 (n = 22,080). Status-quo infection risk declined over time among all groups but remained higher in 2035 for BMSM (incidence rate ratio, 4.76; 95% CI: 4.58 to 4.95), and LMSM (incidence rate ratio, 1.74; 95% CI: 1.69 to 1.80), with the health benefits equally to reasonably distributed across groups (G, 0.32; 95% CI: 0.28 to 0.35). Relative to Status-quo, all other strategies reduced BMSM-WMSM and BMSM-LMSM disparities, but none reduced LMSM-WMSM disparities by 2035. Compared to Status-quo, strategy 3 reduced the most both incident infections (% infections averted: overall, 10.2%; BMSM, 32.4%; LMSM, 3.8%; WMSM, 3.5%) and HIV racial inequalities (G reduction, 0.08; 95% CI: 0.02 to 0.14).

CONCLUSIONS

Microsimulation models developed with early, continuous stakeholder engagement and inputs yield powerful tools to guide policy implementation.

Finding and treating early-stage HIV infections: A cost-effectiveness analysis of the Sabes study in Lima, Peru

Background

Sabes, a treatment-as-prevention intervention among men who have sex with men and transgender women in Lima, Peru, was developed to identify HIV during early primary infection (<3 months from acquisition) through monthly serologic assays and HIV RNA tests. Newly diagnosed individuals were rapidly linked to care and offered to initiate ART. In this study we sought to study the cost-effectiveness of Sabes compared to the standard of care (SOC) for HIV testing and initiation of treatment.

Methods

We adapted a compartmental model of HIV transmission to evaluate the cost-effectiveness of the Sabes approach compared to the SOC using a government health care perspective, 20-year time horizon, and 3% annual discounting. We estimated the proportion of cases of HIV detected during early primary infection, reduction in HIV incidence and prevalence, incremental cost-effectiveness ratio (ICER), and net monetary benefit. We analyzed costs using data from the Sabes study, the Peruvian Ministry of Health, published literature, and expert consultation.

Findings

The Sabes intervention is projected to identify 9294 early primary HIV infections in Lima, Peru over 20 years. The intervention costs $6,896 per early primary infection diagnosed and by 2038 is expected to decrease the fraction of early infections among prevalent infections by 62%. Sabes is expected to improve health, resulting in greater total discounted QALYs per person than the SOC (16·7 vs 16·4, respectively). Sabes had an ICER of $1431 (22% per capita GDP in Peru) per QALY compared to SOC.

Interpretation

Our analysis suggests that in Lima, Peru the Sabes intervention could be a cost-effective approach to reduce the burden of HIV even under stringent cost-effectiveness criteria. This finding suggests that programs that use frequent HIV testing, rapid linkage to care and initiation of ART should be considered as part of a comprehensive HIV prevention strategy.

Funding

National Institutes of Health.

Health economics modeling of antiretroviral interventions amongst HIV serodiscordant couples

Antiretroviral treatment (ART) and pre-exposure prophylaxis (PrEP) for HIV-serodiscordant couples, effectively reduce mortality, transmission events and influence quality of life at the expense of increased costs. We aimed to evaluate health economics of antiretroviral-based strategies for HIV-serodiscordant couples in the China context. A deterministic model of HIV evolution and transmission within a cohort of serodiscordant couples was parameterized using the real-world database of Zhoukou city and published literature. We evaluated the mid-ART (a historical strategy, initiating ART with CD4 < 500 cells/mm³), early-ART (the current strategy, offering ART regardless of CD4 cell counts) and a hypothetical strategy (early-ART combined short-term daily PrEP) versus the late-ART (the baseline strategy, initiating ART with CD4 < 350 cells/mm³) offered by 2008 national guidelines. We estimated the incremental cost-effectiveness ratios (ICER) and incremental cost-utility ratios (ICUR) from a societal perspective, derived by clinical benefits and HIV-caused life quality respectively, and portrayed their changes over a 0-30 year's timeframe. The model projections indicated that the antiretroviral-based interventions were more likely to obtain clinical benefits but difficult to improve quality of life, and cumulative ICER and ICUR were generally decreasing without achieving cost-saving. Scale-up access to ART for the HIV-positive among serodiscordant couples was easily fallen within the range of paying for incremental life-years and quality adjusted life years by the societal willingness. The hypothetical strategy had the potential to prevent most seroconversion events within marriages but required enormous upfront costs, thus it took a long time to reach established thresholds. The current strategy of early-ART is the most cost-effective. Clarifying the obstacles of high cost of PrEP and improving life quality for HIV-serodiscordant couples have emerged as an urgent requisition.

Cost-Effectiveness of antiretroviral therapy: A systematic review

Background

The mobilization of resources to prevent and treat human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) is unparalleled in the history of public health. The uptake of antiretroviral therapy (ART) has been rapid and unprecedented and made possible by the availability of funding - external and domestic. To justify continuous funding of ART in resource-scarce settings, a spate of cost-effectiveness studies has been undertaken in a number of countries. This paper is based on a systematic review of global studies on cost-effectiveness analysis of ART.

Objectives

The major objective was to review the existing literature on cost-effectiveness of ART to determine whether ART has been cost-effective (CE) in different settings.

Methods

We searched PubMed and Google Scholar for articles published between 2008 and 2017. We included studies that measured costs as well as effectiveness of HIV treatment - specifically ART - using incremental cost-effectiveness ratio as one of the outcomes.

Results

We identified 15 studies that met the search criteria for inclusion in the systematic review. The review confirms that ART programs have been CE across different settings, contexts, and strategies.

Conclusion

The review would be useful for countries that are straining to raise funds for the health sector, generally, and for AIDS prevention and control program, specifically. This would also be beneficial for carrying out similar studies, if necessary, and as an advocacy tool for garnering additional funding.

Shortened Tuberculosis Treatment for People with HIV in South Africa. A Model-based Evaluation and Cost-effectiveness Analysis

Rationale: Recent tuberculosis treatment trials failed to show that some 4-month (4m) regimens were noninferior to conventional 6-month (6m) regimens for a composite clinical outcome. Novel shortened regimens may still have important clinical and economic benefits in populations with high loss to follow-up (LTFU) and in subgroups such as people with human immunodeficiency virus.Objectives: To identify scenarios in which a novel 4m regimen would be preferred to a conventional 6m regimen for treatment of drug-susceptible tuberculosis in people with human immunodeficiency virus in South Africa, in terms of short-term and long-term clinical and economic outcomes.Methods: We used the Cost-Effectiveness of Preventing AIDS Complications-International microsimulation model to project outcomes modeled on participants in the OFLOTUB trial. For calibration purposes, we did a base case analysis by applying trial-informed parameters for the 4m/6m regimens, including monthly LTFU during treatment (0.68%/0.83%), average monthly tuberculosis recurrence (0.65%/0.31%), and monthly drug costs (U.S. dollars [USD]25.90/3.70). We then evaluated different scenarios and 4m regimen characteristics, varying key parameters, including LTFU (informed by observational cohort data), recurrence, and cost. We projected outcomes, including 2-year mortality and life expectancy. We conducted a cost-effectiveness analysis, evaluating the incremental cost-effectiveness ratio of a 4m versus 6m regimen.Results: In the base case model analysis, risk of the composite unfavorable outcome in the 4m/6m groups was 19.8%/15.9%, similar to the trial; projected life expectancies were 22.1/22.3 years. In analyses of alternative scenarios and 4m regimen characteristics, a 4m regimen yielded lower risk of the composite unfavorable outcome than the conventional 6m regimen if LTFU increased to greater than 3.5%/mo or if average recurrence after a 4m regimen decreased to less than 0.45%/mo, and it yielded higher life expectancy if LTFU was greater than 3.5%/mo or if recurrence was less than 0.5%/mo. A 4m regimen was not cost-effective in the base case but became cost-effective (incremental cost-effectiveness ratio <USD940/yr of life saved) in two-way sensitivity analysis; for example, if LTFU was greater than or equal to 5.3%/mo and either average recurrence was less than or equal to 0.5%/mo or drug cost was less than or equal to USD15/mo.Conclusions: A novel shortened tuberculosis treatment regimen could improve outcomes such as survival despite conferring a higher recurrence risk, particularly in settings where LTFU is higher than that seen in recent trials.

Cost-effectiveness of a novel lipoarabinomannan test for tuberculosis in patients with HIV

Background

A novel urine lipoarabinomannan assay (FujiLAM) has higher sensitivity and higher cost than the first-generation AlereLAM assay. We evaluated the cost-effectiveness of FujiLAM for tuberculosis testing among hospitalized people with human immunodeficiency virus (HIV), irrespective of symptoms.

Methods

We used a microsimulation model to project clinical and economic outcomes of 3 testing strategies: (1) sputum Xpert MTB/RIF (Xpert), (2) sputum Xpert plus urine AlereLAM (Xpert+AlereLAM), (3) sputum Xpert plus urine FujiLAM (Xpert+FujiLAM). The modeled cohort matched that of a 2-country clinical trial. We applied diagnostic yields from a retrospective study (yields for Xpert/Xpert+AlereLAM/Xpert+FujiLAM among those with CD4 <200 cells/µL: 33%/62%/70%; among those with CD4 ≥200 cells/µL: 33%/35%/47%). Costs of Xpert/AlereLAM/FujiLAM were US$15/3/6 (South Africa) and $25/3/6 (Malawi). Xpert+FujiLAM was considered cost-effective if its incremental cost-effectiveness ratio (US$/year-of-life saved) was <$940 (South Africa) and <$750 (Malawi). We varied key parameters in sensitivity analysis and performed a budget impact analysis of implementing FujiLAM countrywide.

Results

Compared with Xpert+AlereLAM, Xpert+FujiLAM increased life expectancy by 0.2 years for those tested in South Africa and Malawi. Xpert+FujiLAM was cost-effective in both countries. Xpert+FujiLAM for all patients remained cost-effective compared with sequential testing and CD4-stratified testing strategies. FujiLAM use added 3.5% (South Africa) and 4.7% (Malawi) to 5-year healthcare costs of tested patients, primarily reflecting ongoing HIV treatment costs among survivors.

Conclusions

FujiLAM with Xpert for tuberculosis testing in hospitalized people with HIV is likely to increase life expectancy and be cost-effective at the currently anticipated price in South Africa and Malawi. Additional studies should evaluate FujiLAM in clinical practice settings.

Novel microsimulation model of tobacco use behaviours and outcomes: calibration and validation in a US population

BACKGROUND AND OBJECTIVE

Simulation models can project effects of tobacco use and cessation and inform tobacco control policies. Most existing tobacco models do not explicitly include relapse, a key component of the natural history of tobacco use. Our objective was to develop, calibrate and validate a novel individual-level microsimulation model that would explicitly include smoking relapse and project cigarette smoking behaviours and associated mortality risks.

METHODS

We developed the Simulation of Tobacco and Nicotine Outcomes and Policy (STOP) model, in which individuals transition monthly between tobacco use states (current/former/never) depending on rates of initiation, cessation and relapse. Simulated individuals face tobacco use-stratified mortality risks. For US women and men, we conducted cross-validation with a Cancer Intervention and Surveillance Modeling Network (CISNET) model. We then incorporated smoking relapse and calibrated cessation rates to reflect the difference between a transient quit attempt and sustained abstinence. We performed external validation with the National Health Interview Survey (NHIS) and the linked National Death Index. Comparisons were based on root-mean-square error (RMSE).

RESULTS

In cross-validation, STOP-generated projections of current/former/never smoking prevalence fit CISNET-projected data well (coefficient of variation (CV)-RMSE≤15%). After incorporating smoking relapse, multiplying the CISNET-reported cessation rates for women/men by 7.75/7.25, to reflect the ratio of quit attempts to sustained abstinence, resulted in the best approximation to CISNET-reported smoking prevalence (CV-RMSE 2%/3%). In external validation using these new multipliers, STOP-generated cumulative mortality curves for 20-year-old current smokers and never smokers each had CV-RMSE ≤1% compared with NHIS. In simulating those surveyed by NHIS in 1997, the STOP-projected prevalence of current/former/never smokers annually (1998-2009) was similar to that reported by NHIS (CV-RMSE 12%).

CONCLUSIONS

The STOP model, with relapse included, performed well when validated to US smoking prevalence and mortality. STOP provides a flexible framework for policy-relevant analysis of tobacco and nicotine product use.

Modelling the epidemiologic impact of achieving UNAIDS fast-track 90-90-90 and 95-95-95 targets in South Africa

UNAIDS established fast-track targets of 73% and 86% viral suppression among human immunodeficiency virus (HIV)-positive individuals by 2020 and 2030, respectively. The epidemiologic impact of achieving these goals is unknown. The HIV-Calibrated Dynamic Model, a calibrated agent-based model of HIV transmission, is used to examine scenarios of incremental improvements to the testing and antiretroviral therapy (ART) continuum in South Africa in 2015. The speed of intervention availability is explored, comparing policies for their predicted effects on incidence, prevalence and achievement of fast-track targets in 2020 and 2030. Moderate (30%) improvements in the continuum will not achieve 2020 or 2030 targets and have modest impacts on incidence and prevalence. Improving the continuum by 80% and increasing availability reduces incidence from 2.54 to 0.80 per 100 person-years (-1.73, interquartile range (IQR): -1.42, -2.13) and prevalence from 26.0 to 24.6% (-1.4 percentage points, IQR: -0.88, -1.92) from 2015 to 2030 and achieves fast track targets in 2020 and 2030. Achieving 90-90-90 in South Africa is possible with large improvements to the testing and treatment continuum. The epidemiologic impact of these improvements depends on the balance between survival and transmission benefits of ART with the potential for incidence to remain high.

Simulating system dynamics of the HIV care continuum to achieve treatment as prevention

The continuing HIV pandemic calls for broad, multi-sectoral responses that foster community control of local prevention and care services, with the goal of leveraging high quality treatment as a means of reducing HIV incidence. Service system improvements require stakeholder input from across the care continuum to identify gaps and to inform strategic plans that improve HIV service integration and delivery. System dynamics modeling offers a participatory research approach through which stakeholders learn about system complexity and about ways to achieve sustainable system-level improvements. Via an intensive group model building process with a task force of community stakeholders with diverse roles and responsibilities for HIV service implementation, delivery and surveillance, we designed and validated a multi-module system dynamics model of the HIV care continuum, in relation to local prevention and care service capacities. Multiple sources of data were used to calibrate the model for a three-county catchment area of central Connecticut. We feature a core module of the model for the purpose of illustrating its utility in understanding the dynamics of treatment as prevention at the community level. We also describe the methods used to validate the model and support its underlying assumptions to improve confidence in its use by stakeholders for systems understanding and decision making. The model’s generalizability and implications of using it for future community-driven strategic planning and implementation efforts are discussed.

The short-term effects of the implementation of the "Treat All" guidelines on ART service delivery costs in Namibia

The introduction of “Treat All” (TA) has been promoted to increase the effectiveness of HIV/AIDS treatment by having patients initiate antiretroviral therapy at an earlier stage of their illness. The impact of introducing TA on the unit cost of treatment has been less clear. The following study evaluated how costs changed after Namibia’s introduction of TA in April 2017. A two-year analysis assessed the costs of antiretroviral therapy (ART) during the 12 months before TA (Phase I–April 1, 2016 to March 31, 2017) and the 12 months following (Phase II–April 1, 2017 to March 31, 2018). The analysis involved interviewing staff at ten facilities throughout Namibia, collecting data on resources utilized in the treatment of ART patients and analyzing how costs changed before and after the introduction of TA. An analysis of treatment costs indicated that the unit cost of treatment declined from USD360 per patient per year in Phase I to USD301 per patient per year in Phase II, a reduction of 16%. This decline in unit costs was driven by 3 factors: 1) shifts in antiretroviral (ARV) regimens that resulted in lower costs for drugs and consumables, 2) negotiated reductions in the cost of viral load tests and 3) declines in personnel costs. It is unlikely that the first two of these factors were significantly influenced by the introduction of TA. It is unclear if TA might have had an influence on personnel costs. The reduction in personnel costs may have either represented a positive development (fewer personnel costs associated with increased numbers of healthier patients and fewer visits required) or alternatively may reflect constraints in Namibia’s staffing. Prior to this study, it was expected that the introduction of TA would lead to a significant increase in the number of ART patients. However, there was less than a 4% increase in the number of adult patients at the 10 studied facilities. From a financial point of view, TA did not significantly increase the resources required in the ten sampled facilities, either by raising unit costs or significantly increasing the number of ART patients.

Prevention of HIV Transmission and the HPTN 052 Study

The HIV Prevention Trials Network 052 study (HPTN 052) was a clinical trial designed to determine whether early treatment for HIV infection prevented transmission of the virus in couples where one partner was infected with HIV and the other was not, referred to as HIV serodiscordant or serodifferent couples. The study enrolled 1,763 couples at 13 sites in 9 countries in Asia, Africa, and the Americas. HPTN 052 demonstrated a minimum of 96% reduction of HIV in heterosexual couples ascribed to antiretroviral treatment; early treatment of HIV significantly reduced other infections in the HIV-infected subjects. This study, in conjunction with similar research, led to significant changes in international HIV treatment guidelines and the concept of treatment as prevention (TasP). This article provides the scientific background and history of how HPTN 052 came into being, the challenges it faced, and the ultimate impact it had on the fields of HIV treatment and prevention.

Cost-effectiveness of integrating postpartum antiretroviral therapy and infant care into maternal & child health services in South Africa

Background

Poor engagement in postpartum maternal HIV care is a challenge worldwide and contributes to adverse maternal outcomes and vertical transmission. Our objective was to project the clinical and economic impact of integrated postpartum maternal antiretroviral therapy (ART) and pediatric care in South Africa.

Methods

Using the CEPAC computer simulation models, parameterized with data from the Maternal and Child Health–Antiretroviral Therapy (MCH-ART) randomized controlled trial, we evaluated the cost-effectiveness of integrated postpartum care for women initiating ART in pregnancy and their children. We compared two strategies: 1) standard of care (SOC) referral to local clinics after delivery for separate standard ART services for women and pediatric care for infants, and 2) the MCH-ART intervention (MCH-ART) of co-located maternal/pediatric care integrated in Maternal and Child Health (MCH) services throughout breastfeeding. Trial-derived inputs included: 12-month maternal retention in care and virologic suppression (SOC: 49%, MCH-ART: 67%), breastfeeding duration (SOC: 6 months, MCH-ART: 8 months), and postpartum healthcare costs for mother-infant pairs (SOC: $50, MCH-ART: $69). Outcomes included pediatric HIV infections, maternal and infant life expectancy (LE), lifetime HIV-related per-person costs, and incremental cost-effectiveness ratios (ICERs; ICER <US$903/YLS considered “cost-effective”).

Results

Compared to SOC, MCH-ART increased maternal LE (SOC: 25.26 years, MCH-ART: 26.20 years) and lifetime costs (SOC: $9,912, MCH-ART: $10,207; discounted). Projected pediatric outcomes for all HIV-exposed children were similar between arms, although undiscounted LE for HIV-infected children was shorter in SOC (SOC: 23.13 years, MCH-ART: 23.40 years). Combining discounted maternal and pediatric outcomes, the ICER was $599/YLS.

Conclusion

Co-located maternal HIV and pediatric care, integrated in MCH services throughout breastfeeding, is a cost-effective strategy to improve maternal and pediatric outcomes and should be implemented in South Africa.

Structural Design and Data Requirements for Simulation Modelling in HIV/AIDS: A Narrative Review

Born out of a necessity for fiscal sustainability, simulation modeling is playing an increasingly prominent role in setting priorities for combination implementation strategies for HIV treatment and prevention globally. The design of a model and the data inputted into it are central factors in ensuring credible inferences. We executed a narrative review of a set of dynamic HIV transmission models to comprehensively synthesize and compare the structural design and the quality of evidence used to support each model. We included 19 models representing both generalized and concentrated epidemics, classified as compartmental, agent-based, individual-based microsimulation or hybrid in our review. We focused on four structural components (population construction; model entry, exit and HIV care engagement; HIV disease progression; and the force of HIV infection), and two analytical components (model calibration/validation; and health economic evaluation, including uncertainty analysis). While the models we reviewed focused on a variety of individual interventions and their combinations, their structural designs were relatively homogenous across three of the four focal components, with key structural elements influenced by model type and epidemiological context. In contrast, model entry, exit and HIV care engagement tended to differ most across models, with some health system interactions-particularly HIV testing-not modeled explicitly in many contexts. The quality of data used in the models and the transparency with which the data was presented differed substantially across model components. Representative and high-quality data on health service delivery were most commonly not accessed or were unavailable. The structure of an HIV model should ideally fit its epidemiological context and be able to capture all efficacious treatment and prevention services relevant to a robust combination implementation strategy. Developing standardized guidelines on evidence syntheses for health economic evaluation would improve transparency and help prioritize data collection to reduce decision uncertainty.

Moving Metaphors: Shifting Institutional Responsibilities and Evidentiary Boundaries in the Commissioning of Pre-Exposure Prophylaxis for HIV

In this article, we investigate how speakers in the U.K.'s House of Commons cited the same legislative context and medical research to arrive at contradictory conclusions regarding the Government's responsibility to fund pre-exposure prophylaxis (PrEP) as an HIV intervention. Because the Government had expressed that it would not comment on institutional responsibilities directly, given the likelihood of a legal challenge in response to the National Health Service withdrawing PrEP from the drug commissioning process, the Government's support of this decision could not be explicitly detailed. Our discourse analytic approach reveals how members of parliament adopted positions in the debate by using distinct metaphorical frames and lexical choices to linguistically encode assumptions that imply contrary interpretations of mutually agreed upon facts. This suggests that the concrete discursive practices used to cite evidence in policy-making discussions, regardless of the quality of the evidence, may have material consequences for evidence-based policy.

Rapid, point-of-care diagnosis of tuberculosis with novel Truenat assay: Cost-effectiveness analysis for India's public sector

Background

Truenat is a novel molecular assay that rapidly detects tuberculosis (TB) and rifampicin-resistance. Due to the portability of its battery-powered testing platform, it may be valuable in peripheral healthcare settings in India.

Methods

Using a microsimulation model, we compared four TB diagnostic strategies for HIV-negative adults with presumptive TB: (1) sputum smear microscopy in designated microscopy centers (DMCs) (SSM); (2) Xpert MTB/RIF in DMCs (Xpert); (3) Truenat in DMCs (Truenat DMC); and (4) Truenat for point-of-care testing in primary healthcare facilities (Truenat POC). We projected life expectancy, costs, incremental cost-effectiveness ratios (ICERs), and 5-year budget impact of deploying Truenat POC in India’s public sector. We defined a strategy “cost-effective” if its ICER was <US$990/year-of-life saved (YLS). Model inputs included: TB prevalence, 15% (among those not previously treated for TB) and 27% (among those previously treated for TB); sensitivity for TB detection, 89% (Xpert) and 86% (Truenat); per test cost, $12.63 (Xpert) and $13.20 (Truenat); and linkage-to-care after diagnosis, 84% (DMC) and 95% (POC). We varied these parameters in sensitivity analyses.

Results

Compared to SSM, Truenat POC increased life expectancy by 0.39 years and was cost-effective (ICER $210/YLS). Compared to Xpert, Truenat POC increased life expectancy by 0.08 years due to improved linkage-to-care and was cost-effective (ICER $120/YLS). In sensitivity analysis, the cost-effectiveness of Truenat POC, relative to Xpert, depended on the diagnostic sensitivity of Truenat and linkage-to-care with Truenat. Deploying Truenat POC instead of Xpert increased 5-year expenditures by $270 million, due mostly to treatment costs. Limitations of our study include uncertainty in Truenat’s sensitivity for TB and not accounting for the “start-up” costs of implementing Truenat in the field.

Conclusions

Used at the point-of-care in India, Truenat for TB diagnosis should improve linkage-to-care, increase life expectancy, and be cost-effective compared with smear microscopy or Xpert.

Cost-effectiveness and budget impact of immediate antiretroviral therapy initiation for treatment of HIV infection in Côte d'Ivoire: A model-based analysis

Introduction

The Temprano and START trials provided evidence to support early ART initiation recommendations. We projected long-term clinical and economic outcomes of immediate ART initiation in Côte d’Ivoire.

Methods

We used a mathematical model to compare three potential ART initiation criteria: 1) CD4 <350/μL (ART<350/μL); 2) CD4 <500/μL (ART<500/μL); and 3) ART at presentation (Immediate ART). Outcomes from the model included life expectancy, 10-year medical resource use, incremental cost-effectiveness ratios (ICERs) in $/year of life saved (YLS), and 5-year budget impact. We simulated people with HIV (PWH) in care (mean CD4: 259/μL, SD 198/μL) and transmitted cases. Key input parameters to the analysis included first-line ART efficacy (80% suppression at 6 months) and ART cost ($90/person-year). We assessed cost-effectiveness relative to Côte d’Ivoire’s 2017 per capita annual gross domestic product ($1,600).

Results

Immediate ART increased life expectancy by 0.34 years compared to ART<350/μL and 0.17 years compared to ART<500/μL. Immediate ART resulted in 4,500 fewer 10-year transmissions per 170,000 PWH compared to ART<350/μL. In cost-effectiveness analysis, Immediate ART had a 10-year ICER of $680/YLS compared to ART<350/μL, ranging from cost-saving to an ICER of $1,440/YLS as transmission rates varied. ART<500/μL was “dominated” (an inefficient use of resources), compared with Immediate ART. Immediate ART increased the 5-year HIV care budget from $801.9M to $812.6M compared to ART<350/μL.

Conclusions

In Côte d’Ivoire, immediate compared to later ART initiation will increase life expectancy, decrease HIV transmission, and be cost-effective over the long-term, with modest budget impact. Immediate ART initiation is an appropriate, high-value standard of care in Côte d’Ivoire and similar settings.

The cost-effectiveness of HIV pre-exposure prophylaxis in men who have sex with men and transgender women at high risk of HIV infection in Brazil

Introduction

Men who have sex with men (MSM) and transgender women (TGW) in Brazil experience high rates of HIV infection. We examined the clinical and economic outcomes of implementing a pre‐exposure prophylaxis (PrEP) programme in these populations.

Methods

We used the Cost‐Effectiveness of Preventing AIDS Complications (CEPAC)‐International model of HIV prevention and treatment to evaluate two strategies: the current standard of care (SOC) in Brazil, including universal ART access (No PrEP strategy); and the current SOC plus daily tenofovir/emtracitabine PrEP (PrEP strategy) until age 50. Mean age (31 years, SD 8.4 years), age‐stratified annual HIV incidence (age ≤ 40 years: 4.3/100 PY; age > 40 years: 1.0/100 PY), PrEP effectiveness (43% HIV incidence reduction) and PrEP drug costs ($23/month) were from Brazil‐based sources. The analysis focused on direct medical costs of HIV care. We measured the comparative value of PrEP in 2015 United States dollars (USD) per year of life saved (YLS). Willingness‐to‐pay threshold was based on Brazil's annual per capita gross domestic product (GDP; 2015: $8540 USD).

Results

Lifetime HIV infection risk among high‐risk MSM and TGW was 50.5% with No PrEP and decreased to 40.1% with PrEP. PrEP increased per‐person undiscounted (discounted) life expectancy from 36.8 (20.7) years to 41.0 (22.4) years and lifetime discounted HIV‐related medical costs from $4100 to $8420, which led to an incremental cost‐effectiveness ratio (ICER) of $2530/YLS. PrEP remained cost‐effective (<1x GDP) under plausible variation in key parameters, including PrEP effectiveness and cost, initial cohort age and HIV testing frequency on/off PrEP.

Conclusion

Daily tenofovir/emtracitabine PrEP among MSM and TGW at high risk of HIV infection in Brazil would increase life expectancy and be highly cost‐effective.

Randomized feasibility trial of directly observed versus unobserved hepatitis C treatment with ledipasvir-sofosbuvir among people who inject drugs

AIMS

The advent of direct-acting antivirals for hepatitis C virus (HCV) and limited effectiveness of prevention have generated interest in "Treatment as Prevention" (TasP), in which those most likely to transmit HCV (i.e. people who inject drugs [PWID]) are treated to reduced secondary transmission. However, there are scant data regarding the feasibility of treating PWID at high risk for secondary transmission or the optimal approach to treatment delivery.

METHODS

We conducted a 2:1 randomized trial of modified directly-observed (mDOT) versus unobserved HCV treatment with ledipasvir-sofosbuvir daily for 8 weeks among PWID with 36 weeks of follow-up in San Francisco from 2015-2017. We evaluated recruitment-enrollment, treatment completion, end-of-treatment and 12-week response, and reinfection rate.

RESULTS

Of 83 individuals eligible for screening, 72 (87.6%) attended the screening visit, 33 were eligible, and 31 enrolled; mean age was 42 years, 81% were male, 74% white. All but one participant (in the mDOT arm) completed treatment and 89.4% of mDOT and 96.6% of unobserved arm visits were attended. HCV was undetectable for 96.8% (30/31) at end of treatment and 89.7% (26/29) 12 weeks later (1 relapse, 1 reinfection), with no differences by arm. Two additional reinfections were subsequently identified, for a reinfection rate of 16.3 (95% CI 5.3-50.5) per 100 person-years of observation.

CONCLUSIONS

It was feasible to recruit active PWID for HCV treatment and achieve high retention, viral response, and satisfaction with either mDOT or unobserved protocols, supporting treatment of PWID at risk of transmitting HCV to others. The reinfection rate suggests we successfully reached a high-risk population and that successful HCV TasP initiatives may aim to be sufficient in scope to significantly lower prevalence in the community.

TRIAL REGISTRATION

clinicaltrials.gov NCT02609893.

Optimal breastfeeding durations for HIV-exposed infants: the impact of maternal ART use, infant mortality and replacement feeding risk

INTRODUCTION

In 2010, the WHO recommended women living with HIV breastfeed for 12 months while taking antiretroviral therapy (ART) to balance breastfeeding benefits against HIV transmission risks. To inform the 2016 WHO guidelines, we updated prior research on the impact of breastfeeding duration on HIV-free infant survival (HFS) by incorporating maternal ART duration, infant/child mortality and mother-to-child transmission data.

METHODS

Using the Cost-Effectiveness of Preventing AIDS Complications (CEPAC)-Infant model, we simulated the impact of breastfeeding duration on 24-month HFS among HIV-exposed, uninfected infants. We defined "optimal" breastfeeding durations as those maximizing 24-month HFS. We varied maternal ART duration, mortality rates among breastfed infants/children, and relative risk of mortality associated with replacement feeding ("RRRF"), modelled as a multiplier on all-cause mortality for replacement-fed infants/children (range: 1 [no additional risk] to 6). The base-case simulated RRRF = 3, median infant mortality, and 24-month maternal ART duration.

RESULTS

In the base-case, HFS ranged from 83.1% (no breastfeeding) to 90.2% (12-months breastfeeding). Optimal breastfeeding durations increased with higher RRRF values and longer maternal ART durations, but did not change substantially with variation in infant mortality rates. Optimal breastfeeding durations often exceeded the previous WHO recommendation of 12 months.

CONCLUSIONS

In settings with high RRRF and long maternal ART durations, HFS is maximized when mothers breastfeed longer than the previously-recommended 12 months. In settings with low RRRF or short maternal ART durations, shorter breastfeeding durations optimize HFS. If mothers are supported to use ART for longer periods of time, it is possible to reduce transmission risks and gain the benefits of longer breastfeeding durations.

Risks and Benefits of Dolutegravir- and Efavirenz-Based Strategies for South African Women With HIV of Child-Bearing Potential: A Modeling Study

BACKGROUND

Dolutegravir is superior to efavirenz for HIV antiretroviral therapy (ART) but may be associated with an increased risk for neural tube defects (NTDs) in newborns if used by women at conception.

OBJECTIVE

To project clinical outcomes of ART policies for women of child-bearing potential in South Africa.

DESIGN

Model of 3 strategies: efavirenz for all women of child-bearing potential (EFV), dolutegravir for all women of child-bearing potential (DTG), or World Health Organization (WHO)-recommended efavirenz without contraception or dolutegravir with contraception (WHO approach).

DATA SOURCES

Published data on NTD risks (efavirenz, 0.05%; dolutegravir, 0.67% [Tsepamo study]), 48-week ART efficacy with initiation (efavirenz, 60% to 91%; dolutegravir, 96%), and age-stratified fertility rates (2 to 139 per 1000 women).

TARGET POPULATION

3.1 million South African women with HIV (aged 15 to 49 years) starting or continuing first-line ART, and their children.

TIME HORIZON

5 years.

PERSPECTIVE

Societal.

INTERVENTION

EFV, DTG, and WHO approach.

OUTCOME MEASURES

Deaths among women and children, sexual and pediatric HIV transmissions, and NTDs.

RESULTS OF BASE-CASE ANALYSIS

Compared with EFV, DTG averted 13 700 women's deaths (0.44% decrease) and 57 700 sexual HIV transmissions, but increased total pediatric deaths by 4400 because of more NTDs. The WHO approach offered some benefits compared with EFV, averting 4900 women's deaths and 20 500 sexual transmissions while adding 300 pediatric deaths. Overall, combined deaths among women and children were lowest with DTG (358 000 deaths) compared with the WHO approach (362 800 deaths) or EFV (367 300 deaths).

RESULTS OF SENSITIVITY ANALYSIS

Women's deaths averted with DTG exceeded pediatric deaths added with EFV unless dolutegravir-associated NTD risk was 1.5% or greater.

LIMITATION

Uncertainty in NTD risks and dolutegravir efficacy in resource-limited settings, each examined in sensitivity analyses.

CONCLUSION

Although NTD risks may be higher with dolutegravir than efavirenz, dolutegravir will lead to many fewer deaths among women, as well as fewer overall HIV transmissions. These results argue against a uniform policy of avoiding dolutegravir in women of child-bearing potential.

PRIMARY FUNDING SOURCE

National Institutes of Health, National Institute of Allergy and Infectious Diseases and Eunice Kennedy Shriver National Institute of Child Health and Human Development; Massachusetts General Hospital; and Harvard University Center for AIDS Research.

Model-Based Methods to Translate Adolescent Medicine Trials Network for HIV/AIDS Interventions Findings Into Policy Recommendations: Rationale and Protocol for a Modeling Core (ATN 161)

Background

The United States Centers for Disease Control and Prevention estimates that approximately 60,000 US youth are living with HIV. US youth living with HIV (YLWH) have poorer outcomes compared with adults, including lower rates of diagnosis, engagement, retention, and virologic suppression. With Adolescent Medicine Trials Network for HIV/AIDS Interventions (ATN) support, new trials of youth-centered interventions to improve retention in care and medication adherence among YLWH are underway.

Objective

This study aimed to use a computer simulation model, the Cost-Effectiveness of Preventing AIDS Complications (CEPAC)-Adolescent Model, to evaluate selected ongoing and forthcoming ATN interventions to improve viral load suppression among YLWH and to define the benchmarks for uptake, effectiveness, durability of effect, and cost that will make these interventions clinically beneficial and cost-effective.

Methods

This protocol, ATN 161, establishes the ATN Modeling Core. The Modeling Core leverages extensive data—already collected by successfully completed National Institutes of Health–supported studies—to develop novel approaches for modeling critical components of HIV disease and care in YLWH. As new data emerge from ongoing ATN trials during the award period about the effectiveness of novel interventions, the CEPAC-Adolescent simulation model will serve as a flexible tool to project their long-term clinical impact and cost-effectiveness. The Modeling Core will derive model input parameters and create a model structure that reflects key aspects of HIV acquisition, progression, and treatment in YLWH. The ATN Modeling Core Steering Committee, with guidance from ATN leadership and scientific experts, will select and prioritize specific model-based analyses as well as provide feedback on derivation of model input parameters and model assumptions. Project-specific teams will help frame research questions for model-based analyses as well as provide feedback regarding project-specific inputs, results, sensitivity analyses, and policy conclusions.

Results

This project was funded as of September 2017.

Conclusions

The ATN Modeling Core will provide critical information to guide the scale-up of ATN interventions and the translation of ATN data into policy recommendations for YLWH in the United States.

A systematic review and cost-effectiveness analyses of the new World Health Organization guidelines for the treatment of HIV-positive adults in India

Background

The World Health Organization (WHO) in 2013 has revised its guidelines on antiretroviral therapy (ART) treatment for human immunodeficiency virus (HIV)-positive adults and further updated it in 2016. Based on the WHO recommendations, in May 2017, National AIDS Control Organisation, India recommended initiation of ART treatment for all people living with HIV, regardless of CD4 count, clinical stage, age, or population. This systematic review aims to assess the clinical effectiveness and cost implication of the new guidelines for India.

Methods

A systematic and comprehensive literature search on PubMed, OvidSP, Cochrane Library, and Google Scholar was carried out. Studies reporting either acquired immunodeficiency syndrome (AIDS) or mortality or both as outcome variables were selected. A meta-analysis of the available studies was carried out. The risk ratio was calculated to assess the reduction in AIDS or mortality or both. Cost-effectiveness analysis using health technology principles evaluating the lives saved in terms of incremental cost-effectiveness ratio and cost per quality-adjusted life years gained was carried out.

Results

Nine eligible studies were included for the meta-analysis. For India, the pooled relative risk of AIDS or mortality or both being 0.84 (95% confidence interval [CI], 0.76-0.92) and 0.78 (95% CI, 0.68-0.89) for ART initiation at CD4 count of ≤350 vs CD4 count of ≤500 and at CD4 count of ≤500 vs CD4 count > 500 cells/mm³, respectively. The incremental cost for per additional life saved is US$ 2592 and US$ 2357 for ART initiation at ≤500 and > 500 CD4 count, respectively.

Conclusion

The adoption of the new WHO guidelines is beneficial with substantial reduction in AIDS or mortality or both. This study suggests that adopting new WHO guidelines is cost-effective for India.

The Cost-Effectiveness of Financial Incentives for Viral Suppression: HPTN 065 Study

OBJECTIVE

To evaluate the cost-effectiveness of financial incentives for human immunodeficiency virus (HIV) viral suppression compared to standard of care.

STUDY DESIGN

Mathematical model of 2-year intervention offering financial incentives ($70 quarterly) for viral suppression (<400 copies/ml³) based on the HPTN 065 clinical trial with HIV patients in the Bronx, NY and Washington, D.C.

METHODS

A disease progression model with HIV transmission risk equations was developed following guidelines from the Second Panel on Cost-Effectiveness in Health and Medicine. We used health care sector and societal perspectives, 3% discount rate, and lifetime horizon. Data sources included trial data (baseline N = 16,208 patients), CDC HIV Surveillance data, and published literature. Outcomes were costs (2017 USD), quality-adjusted life years (QALYs), HIV infections prevented, and incremental cost-effectiveness ratio (ICER).

RESULTS

Financial incentives for viral suppression were estimated to be cost-saving from a societal perspective and cost-effective ($49,877/QALY) from a health care sector perspective. Compared to the standard of care, financial incentives gain 0.06 QALYs and lower discounted lifetime costs by $4210 per patient. The model estimates that incentivized patients transmit 9% fewer infections than the standard-of-care patients. In the sensitivity analysis, ICER 95% credible intervals ranged from cost-saving to $501,610/QALY with 72% of simulations being cost-effective using a $150,000/QALY threshold. Modeling results are limited by uncertainty in efficacy from the clinical trial.

CONCLUSIONS

Financial incentives, as used in HTPN 065, are estimated to improve quality and length of life, reduce HIV transmissions, and save money from a societal perspective. Financial incentives offer a promising option for enhancing the benefits of medication in the United States.

Cost-effectiveness of urine-based tuberculosis screening in hospitalised patients with HIV in Africa: a microsimulation modelling study

BACKGROUND

Testing urine improves the number of tuberculosis diagnoses made among patients in hospital with HIV. In conjunction with the two-country randomised Rapid Urine-based Screening for Tuberculosis to Reduce AIDS-related Mortality in Hospitalised Patients in Africa (STAMP) trial, we used a microsimulation model to estimate the effects on clinical outcomes and the cost-effectiveness of adding urine-based tuberculosis screening to sputum screening for hospitalised patients with HIV.

METHODS

We compared two tuberculosis screening strategies used irrespective of symptoms among hospitalised patients with HIV in Malawi and South Africa: a GeneXpert assay (Cepheid, Sunnyvale, CA, USA) for Mycobacterium tuberculosis and rifampicin resistance (Xpert) in sputum samples (standard of care) versus sputum Xpert combined with a lateral flow assay for M tuberculosis lipoarabinomannan in urine (Determine TB-LAM Ag test, Abbott, Waltham, MA, USA [formerly Alere]; TB-LAM) and concentrated urine Xpert (intervention). A cohort of simulated patients was modelled using selected characteristics of participants, tuberculosis diagnostic yields, and use of hospital resources in the STAMP trial. We calibrated 2-month model outputs to the STAMP trial results and projected clinical and economic outcomes at 2 years, 5 years, and over a lifetime. We judged the intervention to be cost-effective if the incremental cost-effectiveness ratio (ICER) was less than US$750/year of life saved (YLS) in Malawi and $940/YLS in South Africa. A modified intervention of adding only TB-LAM to the standard of care was also evaluated. We did a budget impact analysis of countrywide implementation of the intervention.

FINDINGS

The intervention increased life expectancy by 0·5-1·2 years and was cost-effective, with an ICER of $450/YLS in Malawi and $840/YLS in South Africa. The ICERs decreased over time. At lifetime horizon, the intervention remained cost-effective under nearly all modelled assumptions. The modified intervention was at least as cost-effective as the intervention (ICERs $420/YLS in Malawi and $810/YLS in South Africa). Over 5 years, the intervention would save around 51 000 years of life in Malawi and around 171 000 years of life in South Africa. Health-care expenditure for screened individuals was estimated to increase by $37 million (10·8%) and $261 million (2·8%), respectively.

INTERPRETATION

Urine-based tuberculosis screening of all hospitalised patients with HIV could increase life expectancy and be cost-effective in resource-limited settings. Urine TB-LAM is especially attractive because of high incremental diagnostic yield and low additional cost compared with sputum Xpert, making a compelling case for expanding its use to all hospitalised patients with HIV in areas with high HIV burden and endemic tuberculosis.

FUNDING

UK Medical Research Council, UK Department for International Development, Wellcome Trust, US National Institutes of Health, Royal College of Physicians, Massachusetts General Hospital.

Research priorities to inform "Treat All" policy implementation for people living with HIV in sub-Saharan Africa: a consensus statement from the International epidemiology Databases to Evaluate AIDS (IeDEA)

INTRODUCTION

"Treat All" - the treatment of all people with HIV, irrespective of disease stage or CD4 cell count - represents a paradigm shift in HIV care that has the potential to end AIDS as a public health threat. With accelerating implementation of Treat All in sub-Saharan Africa (SSA), there is a need for a focused agenda and research to identify and inform strategies for promoting timely uptake of HIV treatment, retention in care, and sustained viral suppression and addressing bottlenecks impeding implementation.

METHODS

The Delphi approach was used to develop consensus around research priorities for Treat All implementation in SSA. Through an iterative process (June 2017 to March 2018), a set of research priorities was collectively formulated and refined by a technical working group and shared for review, deliberation and prioritization by more than 200 researchers, implementation experts, policy/decision-makers, and HIV community representatives in East, Central, Southern and West Africa.

RESULTS AND DISCUSSION

The process resulted in a list of nine research priorities for generating evidence to guide Treat All policies, implementation strategies and monitoring efforts. These priorities highlight the need for increased focus on adolescents, men, and those with mental health and substance use disorders - groups that remain underserved in SSA and for whom more effective testing, linkage and care strategies need to be identified. The priorities also reflect consensus on the need to: (1) generate accurate national and sub-national estimates of the size of key populations and describe those who remain underserved along the HIV-care continuum; (2) characterize the timeliness of HIV care and short- and long-term HIV care continuum outcomes, as well as factors influencing timely achievement of these outcomes; (3) estimate the incidence and prevalence of HIV-drug resistance and regimen switching; and (4) identify cost-effective and affordable service delivery models and strategies to optimize uptake and minimize gaps, disparities, and losses along the HIV-care continuum, particularly among underserved populations.

CONCLUSIONS

Reflecting consensus among a broad group of experts, researchers, policy- and decision-makers, PLWH, and other stakeholders, the resulting research priorities highlight important evidence gaps that are relevant for ministries of health, funders, normative bodies and research networks.

Losses to follow-up of HIV-infected people in the Spanish VACH cohort over the period between 2013 and 2014: The importance of sociodemographic factors

OBJECTIVE

To determine the proportion of people infected by HIV or AIDS under follow-up in the VACH Cohort in 2012 who were lost to follow-up from 2013 to 2014, and to establish the sociodemographic features relating to this loss.

METHODS

We considered subjects with less than one recorded consultation per year studied to be lost to follow-up. We built logistic regression models to calculate the odds ratios (OR) and their 95% confidence intervals (95% CI), of the variables relating to loss to follow-up.

RESULTS

The overall percentage of losses to follow-up was 15.5% (95% CI 14.9-16-1). The variables associated with loss to follow up were: not receiving antiretroviral treatment (ART) (OR: 1.948, 95% CI: 1.651 -2.298), being an immigrant (OR: 1.746; 95%CI: 1.494-2.040), intravenous drug consumption being the mechanism for HIV transmission (OR: 1.498, 95% CI: 1.312-1.711), being unemployed (OR: 1.331; 95% CI: 1.179-1.503), being without a partner (OR: 1.948, 95% CI: 1.651-1.298), belonging to a low socioeconomic class (OR: 1.279; 95% CI: 1.143-1.431), and being attended in a hospital with fewer than 1000 patients under follow-up (OR: 1.257, 95% CI: 1.121-1.457), as well as being under age and having spent less time under follow-up in the Cohort.

CONCLUSIONS

15.5% of the patients were lost to follow-up over a period of 2years in the VACH Cohort. This was associated with a series of sociodemographic and epidemiological variables that it might be useful to identify to design initiatives targeting the populations most likely to abandon the circuits of care, and guide strategies towards achieving Objective 90-90-90.

Partners-based HIV treatment for seroconcordant couples attending antenatal and postnatal care in rural Mozambique: A cluster randomized trial protocol

BACKGROUND

In resource-limited rural settings, scale-up of services to eliminate mother-to-child transmission of HIV has not been as effective as in better resourced urban settings. In sub-Saharan Africa, women often require male partner approval to access and remain engaged in HIV care. Our study will evaluate a promising male engagement intervention ("Homens para Saúde Mais" (HoPS+) [Men for Health Plus]) targeting the elimination of mother-to-child transmission in rural Mozambique.

DESIGN

We will use a cluster randomized clinical trial design to engage 24 health facilities (12 intervention and 12 standard of care), with 45 HIV-infected seroconcordant couples per clinic. The planned intervention will engage male partners to address social-structural and cultural factors influencing eMTCT based on new couple-centered integrated HIV services.

CONCLUSIONS

The HoPS+ study will evaluate the effectiveness of engaging male partners in antenatal care to improve outcomes among HIV-infected pregnant women, their HIV-infected male partners, and their newborn children. Our objectives are to: (1) Implement and evaluate the impact of male-engaged, couple-centered services on partners' retention in care, adherence to antiretroviral therapy, early infant diagnosis uptake, and mother-to-child transmission throughout pregnancy and breastfeeding; (2) Investigate the impact of HoPS+ intervention on hypothesized mechanisms of change; and (3) Use validated simulation models to evaluate the cost-effectiveness of the HoPS+ intervention with the use of routine clinical data from our trial. We expect the intervention to lead to strategies that can improve outcomes related to partners' retention in care, uptake of services for HIV-exposed infants, and reduced MTCT.

High CD4 counts associated with better economic outcomes for HIV-positive adults and their HIV-negative household members in the SEARCH Trial

Background

Country decisions to scale-up “test and treat” approaches for HIV depend on consideration of both the health and economic consequences of such investments. Evidence about economic impacts of expanded antiretroviral therapy (ART) provision is particularly relevant for decisions regarding foreign assistance levels for HIV/AIDS programs. We used baseline data from the Sustainable East Africa Research in Community Health (SEARCH) cluster randomized controlled trial in Kenya and Uganda to examine the association between HIV status, CD4+ T-cell counts, viral suppression, and multiple indicators of economic well-being.

Methods and findings

Socio-economic surveys were conducted in households with HIV-positive and HIV-negative adults sampled after a census of 32 communities participating in the SEARCH trial (NCT01864603). Data were obtained for 11,500 individuals from 5,884 households in study communities. Participants were stratified based on their own HIV status as well as CD4 counts and viral suppression status if they were HIV-positive. HIV-negative participants residing in households with no HIV-positive adults were considered separately from HIV-negative participants residing in households with ≥1 HIV-positive adult. Generalized estimating equation models were used to examine the relationship between HIV status, CD4 counts, ART, viral suppression, and outcomes of employment, self-reported illness, lost time from usual activities due to illness, healthcare utilization, health expenditures, and hospitalizations. In all models, HIV-negative participants in households with no HIV-positive persons were the reference group.

There was no significant difference in the probability of being employed between HIV-positive participants with CD4>500 and the reference group of HIV-negative participants residing in households with no HIV-positive adults (marginal effect, ME, 1.49 percentage points; 95% confidence interval, CI, -1.09, 4.08). However, HIV-positive participants with CD4 351–500 were less likely to be employed than the reference group (ME -4.50, 95% CI -7.99, -1.01), as were HIV-positive participants with CD4 ≤350 (ME -7.41, 95% CI -10.96, -3.85). Similarly, there was no significant difference in employment likelihood between HIV-negative participants who resided in households with a CD4>500 HIV-positive person and the reference group (ME -1.78, 95% CI -5.16, 1.59). HIV-negative participants residing with an HIV-positive person with CD4 351–500, however, were less likely to be employed than the reference group (ME -7.03, 95% CI -11.49, -2.57), as were people residing with a household member with CD4 ≤350 (ME -6.28, 95% CI -10.76, -1.80). HIV-positive participants in all CD4 categories were more likely to have lost time from usual activities due to illness and have incurred healthcare expenditures. Those with CD4>500 had better economic outcomes than those with CD4 351–500, even among those not virally suppressed (p = 0.004) and not on ART (p = 0.01).

Conclusions

Data from a large population-representative sample of households in east Africa showed a strong association between the health of HIV-positive persons and economic outcomes. The findings suggest there may be economic benefits associated with maintaining high CD4 counts, both for HIV-positive persons and their HIV-negative household members. The association of high CD4 counts with improved outcomes is consistent with the hypothesis that early ART initiation can avert declines in employment and other economic outcomes. Prospective longitudinal evaluation is needed to assess the causal impact of early ART initiation on economic functioning of households.

Clinical Benefits and Cost-Effectiveness of Laboratory Monitoring Strategies to Guide Antiretroviral Treatment Switching in India

Current Indian guidelines recommend twice-annual CD4 testing to monitor first-line antiretroviral therapy (ART), with a plasma HIV RNA test to confirm failure if CD4 declines, which would prompt a switch to second-line ART. We used a mathematical model to assess the clinical benefits and cost-effectiveness of alternative laboratory monitoring strategies in India. We simulated a cohort of HIV-infected patients initiating first-line ART and compared 11 strategies with combinations of CD4 and HIV RNA testing at varying frequencies. We included adaptive strategies that reduce the frequency of tests after 1 year from 6 to 12 months for virologically suppressed patients. We projected life expectancy, time on failed first-line ART, cumulative 10-year HIV transmissions, lifetime cost (2014 US dollars), and incremental cost-effectiveness ratios (ICERs). We defined strategies as cost-effective if their ICER was <1 × the Indian per capita gross domestic product (GDP, $1,600). We found that the current Indian guidelines resulted in a per person life expectancy (from mean age 37) of 150.2 months and a per person cost of $2,680. Adding annual HIV RNA testing increased survival by ∼8 months; adaptive strategies were less expensive than similar nonadaptive strategies with similar life expectancy. The most effective strategy with an ICER <1 × GDP was the adaptive HIV RNA strategy (ICER $840/year). Cumulative 10-year transmissions decreased from 27.2/1,000 person-years with standard-of-care to 20.9/1,000 person-years with adaptive HIV RNA testing. In India, routine HIV RNA monitoring of patients on first-line ART would increase life expectancy, decrease transmissions, be cost-effective, and should be implemented.

The cost-effectiveness and budgetary impact of a dolutegravir-based regimen as first-line treatment of HIV infection in India

INTRODUCTION

Dolutegravir (DTG)-based antiretroviral therapy (ART) is recommended for first-line HIV treatment in the US and Europe. Efavirenz (EFV)-based regimens remain the standard of care (SOC) in India. We examined the clinical and economic impact of DTG-based first-line ART in the setting of India's recent guidelines change to treating all patients with HIV infection regardless of CD4 count.

METHODS

We used a microsimulation of HIV disease, the Cost-Effectiveness of Preventing AIDS Complications (CEPAC)-International model, to project outcomes in ART-naive patients under two strategies: (1) SOC: EFV/tenofovir disoproxil fumarate (TDF)/lamivudine (3TC); and (2) DTG: DTG + TDF/3TC. Regimen-specific inputs, including virologic suppression at 48 weeks (SOC: 82% vs. DTG: 90%) and annual costs ($98 vs. $102), were informed by clinical trial data and other sources and varied widely in sensitivity analysis. We compared incremental cost-effectiveness ratios (ICERs), measured in $/year of life saved (YLS), to India's per capita gross domestic product ($1600 in 2015). We compared the budget impact and HIV transmission effects of the two strategies for the estimated 444,000 and 916,000 patients likely to initiate ART in India over the next 2 and 5 years.

RESULTS

Compared to SOC, DTG improved 5-year survival from 76.7% to 83.0%, increased life expectancy from 22.0 to 24.8 years (14.0 to 15.5 years, discounted), averted 13,000 transmitted HIV infections over 5 years, increased discounted lifetime care costs from $3040 to $3240, and resulted in a lifetime ICER of $130/YLS, less than 10% of India's per capita GDP in 2015. DTG maintained an ICER below 50% of India's per capita GDP as long as the annual three-drug regimen cost was ≤$180/year. Over a 2- or 5-year horizon, total undiscounted outlays for HIV-related care were virtually the same for both strategies.

CONCLUSIONS

A generic DTG-based regimen is likely to be cost-effective and should be recommended for initial therapy of HIV infection in India.

Using Observational Data to Calibrate Simulation Models

BACKGROUND

Individual-level simulation models are valuable tools for comparing the impact of clinical or public health interventions on population health and cost outcomes over time. However, a key challenge is ensuring that outcome estimates correctly reflect real-world impacts. Calibration to targets obtained from randomized trials may be insufficient if trials do not exist for populations, time periods, or interventions of interest. Observational data can provide a wider range of calibration targets but requires methods to adjust for treatment-confounder feedback. We propose the use of the parametric g-formula to estimate calibration targets and present a case-study to demonstrate its application.

METHODS

We used the parametric g-formula applied to data from the HIV-CAUSAL Collaboration to estimate calibration targets for 7-y risks of AIDS and/or death (AIDS/death), as defined by the Center for Disease Control and Prevention under 3 treatment initiation strategies. We compared these targets to projections from the Cost-effectiveness of Preventing AIDS Complications (CEPAC) model for treatment-naïve individuals presenting to care in the following year ranges: 1996 to 1999, 2000 to 2002, or 2003 onwards.

RESULTS

The parametric g-formula estimated a decreased risk of AIDS/death over time and with earlier treatment. The uncalibrated CEPAC model successfully reproduced targets obtained via the g-formula for baseline 1996 to 1999, but over-estimated calibration targets in contemporary populations and failed to reproduce time trends in AIDS/death risk. Calibration to g-formula targets improved CEPAC model fit for contemporary populations.

CONCLUSION

Individual-level simulation models are developed based on best available information about disease processes in one or more populations of interest, but these processes can change over time or between populations. The parametric g-formula provides a method for using observational data to obtain valid calibration targets and enables updating of simulation model inputs when randomized trials are not available.

Implementing Generalized Additive Models to Estimate the Expected Value of Sample Information in a Microsimulation Model: Results of Three Case Studies

BACKGROUND

The expected value of sample information (EVSI) can help prioritize research but its application is hampered by computational infeasibility, especially for complex models. We investigated an approach by Strong and colleagues to estimate EVSI by applying generalized additive models (GAM) to results generated from a probabilistic sensitivity analysis (PSA).

METHODS

For 3 potential HIV prevention and treatment strategies, we estimated life expectancy and lifetime costs using the Cost-effectiveness of Preventing AIDS Complications (CEPAC) model, a complex patient-level microsimulation model of HIV progression. We fitted a GAM-a flexible regression model that estimates the functional form as part of the model fitting process-to the incremental net monetary benefits obtained from the CEPAC PSA. For each case study, we calculated the expected value of partial perfect information (EVPPI) using both the conventional nested Monte Carlo approach and the GAM approach. EVSI was calculated using the GAM approach.

RESULTS

For all 3 case studies, the GAM approach consistently gave similar estimates of EVPPI compared with the conventional approach. The EVSI behaved as expected: it increased and converged to EVPPI for larger sample sizes. For each case study, generating the PSA results for the GAM approach required 3 to 4 days on a shared cluster, after which EVPPI and EVSI across a range of sample sizes were evaluated in minutes. The conventional approach required approximately 5 weeks for the EVPPI calculation alone.

CONCLUSION

Estimating EVSI using the GAM approach with results from a PSA dramatically reduced the time required to conduct a computationally intense project, which would otherwise have been impractical. Using the GAM approach, we can efficiently provide policy makers with EVSI estimates, even for complex patient-level microsimulation models.

Consequence of HIV and HCV co-infection on host immune response, persistence and current treatment options

Hepatitis C virus (HCV) is a common opportunistic pathogen especially among Human immunodeficiency virus (HIV) infected patients. Due to incongruous studies, the pathological effect of HCV on HIV induced disease are still not fully understood. While some studies have showed no effect of HCV on HIV infection, others reported a defined role of HCV in aggravating the rates of AIDS-related illnesses and mortality. The explanation of such variances may be due to the host immune response, viral genotypes, sub-type and quasi-species distribution. The factors that complicate the management of HIV/HCV patients are: (1) reduced HCV antibody production, (2) drug interactions, (3) liver disease and (4) different epidemiologic characteristics. However, it is abundantly clear that the morbidity and mortality caused by HCV have increased since the introduction of highly active antiretroviral therapy (HAART) against HIV. In this review, the consequence of HIV/HCV co-infection on host immune response, viral replication, disease progression, mortality and morbidity, viral load, persistence and current treatment options have been discussed. Based on the clinical studies, it is necessary to evaluate the effect of HCV therapy on HIV progression and to provide a fully active HCV treatment for patients receiving HIV treatment. In conclusion, it is recommended to provide fully active HAART therapy in combination with a known HCV therapy.

Treatment of HIV for the Prevention of Transmission in Discordant Couples and at the Population Level

The scientific breakthrough proving that antiretroviral therapy (ART) can halt heterosexual HIV transmission came in the form of a landmark clinical trial conducted among serodiscordant couples. Study findings immediately informed global recommendations for the use of treatment as prevention in serodiscordant couples. The extent to which these findings are generalizable to other key populations or to groups exposed to HIV through nonsexual transmission routes (i.e., anal intercourse or unsafe injection of drugs) has since driven a large body of research. This review explores the history of HIV research in serodiscordant couples, the implications for management of couples, subsequent research on treatment as prevention in other key populations, and challenges in community implementation of these strategies.

Do Less Harm: Evaluating HIV Programmatic Alternatives in Response to Cutbacks in Foreign Aid

BACKGROUND

Resource-limited nations must consider their response to potential contractions in international support for HIV programs.

OBJECTIVE

To evaluate the clinical, epidemiologic, and budgetary consequences of alternative HIV program scale-back strategies in 2 recipient nations, the Republic of South Africa (RSA) and Côte d'Ivoire (CI).

DESIGN

Model-based comparison between current standard (CD4 count at presentation of 0.260 × 109 cells/L, universal antiretroviral therapy [ART] eligibility, and 5-year retention rate of 84%) and scale-back alternatives, including reduced HIV detection, no ART or delayed initiation (when CD4 count is <0.350 × 109 cells/L), reduced investment in retention, and no viral load monitoring or second-line ART.

DATA SOURCES

Published RSA- and CI-specific estimates of the HIV care continuum, ART efficacy, and HIV-related costs.

TARGET POPULATION

HIV-infected persons, including future incident cases.

TIME HORIZON

5 and 10 years.

PERSPECTIVE

Modified societal perspective, excluding time and productivity costs.

OUTCOME MEASURES

HIV transmissions and deaths, years of life, and budgetary outlays (2015 U.S. dollars).

RESULTS OF BASE-CASE ANALYSIS

At 10 years, scale-back strategies increase projected HIV transmissions by 0.5% to 19.4% and deaths by 0.6% to 39.1%. Strategies can produce budgetary savings of up to 30% but no more. Compared with the current standard, nearly every scale-back strategy produces proportionally more HIV deaths (and transmissions, in RSA) than savings. When the least harmful and most efficient alternatives for achieving budget cuts of 10% to 20% are applied, every year of life lost will save roughly $900 in HIV-related outlays in RSA and $600 to $900 in CI.

RESULTS OF SENSITIVITY ANALYSIS

Scale-back programs, when combined, may result in clinical and budgetary synergies and offsets.

LIMITATION

The magnitude and details of budget cuts are not yet known, nor is the degree to which other international partners might step in to restore budget shortfalls.

CONCLUSION

Scaling back international aid to HIV programs will have severe adverse clinical consequences; for similar economic savings, certain programmatic scale-back choices result in less harm than others.

PRIMARY FUNDING SOURCE

National Institutes of Health and Steve and Deborah Gorlin MGH Research Scholars Award.

Differences in health-related quality of life between HIV-positive and HIV-negative people in Zambia and South Africa: a cross-sectional baseline survey of the HPTN 071 (PopART) trial

BACKGROUND

The life expectancy of HIV-positive individuals receiving antiretroviral therapy (ART) is approaching that of HIV-negative people. However, little is known about how these populations compare in terms of health-related quality of life (HRQoL). We aimed to compare HRQoL between HIV-positive and HIV-negative people in Zambia and South Africa.

METHODS

As part of the HPTN 071 (PopART) study, data from adults aged 18-44 years were gathered between Nov 28, 2013, and March 31, 2015, in large cross-sectional surveys of random samples of the general population in 21 communities in Zambia and South Africa. HRQoL data were collected with a standardised generic measure of health across five domains. We used β-distributed multivariable models to analyse differences in HRQoL scores between HIV-negative and HIV-positive individuals who were unaware of their status; aware, but not in HIV care; in HIV care, but who had not initiated ART; on ART for less than 5 years; and on ART for 5 years or more. We included controls for sociodemographic variables, herpes simplex virus type-2 status, and recreational drug use.

FINDINGS

We obtained data for 19 750 respondents in Zambia and 18 941 respondents in South Africa. Laboratory-confirmed HIV status was available for 19 330 respondents in Zambia and 18 004 respondents in South Africa; 4128 (21%) of these 19 330 respondents in Zambia and 4012 (22%) of 18 004 respondents in South Africa had laboratory-confirmed HIV. We obtained complete HRQoL information for 19 637 respondents in Zambia and 18 429 respondents in South Africa. HRQoL scores did not differ significantly between individuals who had initiated ART more than 5 years previously and HIV-negative individuals, neither in Zambia (change in mean score -0·002, 95% CI -0·01 to 0·001; p=0·219) nor in South Africa (0·000, -0·002 to 0·003; p=0·939). However, scores did differ between HIV-positive individuals who had initiated ART less than 5 years previously and HIV-negative individuals in Zambia (-0·006, 95% CI -0·008 to -0·003; p<0·0001). A large proportion of people with clinically confirmed HIV were unaware of being HIV-positive (1768 [43%] of 4128 people in Zambia and 2026 [50%] of 4012 people in South Africa) and reported good HRQoL, with no significant differences from that of HIV-negative people (change in mean HRQoL score -0·001, 95% CI -0·003 to 0·001, p=0·216; and 0·001, -0·001 to 0·001, p=0·997, respectively). In South Africa, HRQoL scores were lower in HIV-positive individuals who were aware of their status but not enrolled in HIV care (change in mean HRQoL -0·004, 95% CI -0·01 to -0·001; p=0·010) and those in HIV care but not on ART (-0·008, -0·01 to -0·004; p=0·001) than in HIV-negative people, but the magnitudes of difference were small.

INTERPRETATION

ART is successful in helping to reduce inequalities in HRQoL between HIV-positive and HIV-negative individuals in this general population sample. These findings highlight the importance of improving awareness of HIV status and expanding ART to prevent losses in HRQoL that occur with untreated HIV progression. The gains in HRQoL after individuals initiate ART could be substantial when scaled up to the population level.

FUNDING

National Institute of Allergy and Infectious Diseases, National Institute on Drug Abuse, National Institute of Mental Health, President's Emergency Plan for AIDS Relief, International Initiative for Impact Evaluation, the Bill & Melinda Gates Foundation.

The value of point-of-care CD4+ and laboratory viral load in tailoring antiretroviral therapy monitoring strategies to resource limitations

OBJECTIVE

To examine the clinical and economic value of point-of-care CD4 (POC-CD4) or viral load monitoring compared with current practices in Mozambique, a country representative of the diverse resource limitations encountered by HIV treatment programs in sub-Saharan Africa.

DESIGN/METHODS

We use the Cost-Effectiveness of Preventing AIDS Complications-International model to examine the clinical impact, cost (2014 US$), and incremental cost-effectiveness ratio [$/year of life saved (YLS)] of ART monitoring strategies in Mozambique. We compare: monitoring for clinical disease progression [clinical ART monitoring strategy (CLIN)] vs. annual POC-CD4 in rural settings without laboratory services and biannual laboratory CD4 (LAB-CD4), biannual POC-CD4, and annual viral load in urban settings with laboratory services. We examine the impact of a range of values in sensitivity analyses, using Mozambique's 2014 per capita gross domestic product ($620) as a benchmark cost-effectiveness threshold.

RESULTS

In rural settings, annual POC-CD4 compared to CLIN improves life expectancy by 2.8 years, reduces time on failed ART by 0.6 years, and yields an incremental cost-effectiveness ratio of $480/YLS. In urban settings, biannual POC-CD4 is more expensive and less effective than viral load. Compared to biannual LAB-CD4, viral load improves life expectancy by 0.6 years, reduces time on failed ART by 1.0 year, and is cost-effective ($440/YLS).

CONCLUSION

In rural settings, annual POC-CD4 improves clinical outcomes and is cost-effective compared to CLIN. In urban settings, viral load has the greatest clinical benefit and is cost-effective compared to biannual POC-CD4 or LAB-CD4. Tailoring ART monitoring strategies to specific settings with different available resources can improve clinical outcomes while remaining economically efficient.

Supporting HIV prevention and reproductive goals in an HIV-endemic setting: taking safer conception services from policy to practice in South Africa

Introduction: Safer conception care encompasses HIV care, treatment and prevention for persons living with HIV and their partners who desire children. In 2012, South Africa endorsed a progressive safer conception policy supporting HIV-affected persons to safely meet reproductive goals. However, aside from select research-supported clinics, widespread implementation has not occurred. Using South Africa as a case study, we identify key obstacles to policy implementation and offer recommendations to catalyse expansion of these services throughout South Africa and further afield.

Discussion: Four key implementation barriers were identified by combining authors’ safer conception service delivery experiences with available literature. First, strategic implementation frameworks stipulating where, and by whom, safer conception services should be provided are needed. Integrating safer conception services into universal test-and-treat (UTT) and elimination-of-mother-to-child-transmission (eMTCT) priority programmes would support HIV testing, ART initiation and management, viral suppression and early antenatal/eMTCT care engagement goals, reducing horizontal and vertical transmissions. Embedding measurable safer conception targets into these priority programmes would ensure accountability for implementation progress. Second, facing an organizational clinic culture that often undermines clients’ reproductive rights, healthcare providers’ (HCP) positive experiences with eMTCT and enthusiasm for UTT provide opportunities to shift facility-level and individual attitudes in favour of safer conception provision. Third, safer conception guidelines have not been incorporated into HCP training. Combining safer conception with “test-and-treat” training would efficiently ensure that providers are better equipped to discuss clients’ reproductive goals and support safer conception practices. Lastly, HIV-affected couples remain largely unaware of safer conception strategies. HIV-affected populations need to be mobilized to engage with safer conception options alongside other HIV-related healthcare services.

Conclusion: Key barriers to widespread safer conception service provision in South Africa include poor translation of policy into practical and measurable implementation plans, inadequate training and limited community engagement. South Africa should leverage the momentum and accountability associated with high priority UTT and eMTCT programmes to reinvigorate implementation efforts by incorporating safer conception into implementation and monitoring frameworks and associated HCP training and community engagement activities. South Africa’s experiences should be used to inform policy development and implementation processes in other HIV high-burden countries.

Betting on the fastest horse: Using computer simulation to design a combination HIV intervention for future projects in Maharashtra, India

Objective

To inform the design of a combination intervention strategy targeting HIV-infected unhealthy alcohol users in Maharashtra, India, that could be tested in future randomized control trials.

Methods

Using probabilistic compartmental simulation modeling we compared intervention strategies targeting HIV-infected unhealthy alcohol users on antiretroviral therapy (ART) in Maharashtra, India. We tested interventions targeting four behaviors (unhealthy alcohol consumption, risky sexual behavior, depression and antiretroviral adherence), in three formats (individual, group based, community) and two durations (shorter versus longer). A total of 5,386 possible intervention combinations were tested across the population for a 20-year time horizon and intervention bundles were narrowed down based on incremental cost-effectiveness analysis using a two-step probabilistic uncertainty analysis approach.

Results

Taking into account uncertainty in transmission variables and intervention cost and effectiveness values, we were able to reduce the number of possible intervention combinations to be used in a randomized control trial from over 5,000 to less than 5. The most robust intervention bundle identified was a combination of three interventions: long individual alcohol counseling; weekly Short Message Service (SMS) adherence counseling; and brief sex risk group counseling.

Conclusions

In addition to guiding policy design, simulation modeling of HIV transmission can be used as a preparatory step to trial design, offering a method for intervention pre-selection at a reduced cost.

Setting Performance Standards for a Cost-Effective Human Immunodeficiency Virus Cure Strategy in South Africa

BACKGROUND

Reports of a single case of human immunodeficiency virus (HIV) eradication suggest that elimination of HIV from individuals is possible. Anticipating both increased research funding and the development of effective, durable cure technologies, we describe the circumstances under which a cure might improve survival and be cost-effective in South Africa.

METHODS

We adapted a simulation model comparing a hypothetical cure strategy ("Cure") to the standard of care, lifetime antiretroviral therapy ("LifetimeART") among adherent South Africans (58% female; mean age 33.8 years; mean CD4 257/µL; virologic suppression ≥1 year). We portrayed cure as a single intervention, producing sustained viral eradication without ART. We considered both a plausible, more imminently achievable "Baseline Scenario" and a more aspirational "Optimistic Scenario". Inputs (Baseline/Optimistic) included the following: 50%/75% efficacy; 0.6%/0.0% fatal toxicity; 0.37%/0.085% monthly relapse over 5 years (0.185%/0.0425% per month thereafter); and $2000/$500 cost. These inputs were varied extensively in sensitivity analysis.

RESULTS

At baseline, Cure was "dominated," yielding lower discounted life expectancy (19.31 life-years [LY] vs 19.37 LY) and greater discounted lifetime costs ($13 800 vs $13 700) than LifetimeART. Under optimistic assumptions, Cure was "cost-saving," producing greater survival (19.91 LY) and lower lifetime costs ($11 000) than LifetimeART. Findings were highly sensitive to data assumptions, leaving little middle ground where a tradeoff existed between improved survival and higher costs.

CONCLUSIONS

Only under the most favorable performance assumptions will an HIV cure strategy prove clinically and economically justifiable in South Africa. The scientific pursuit of a cure should not undermine continued expansions of access to proven, effective, and cost-effective ART.