Treatment as Prevention: Concepts and Challenges for Reducing HIV Incidence

Assessing Direct and Spillover Effects of Intervention Packages in Network-randomized Studies

BACKGROUND

Intervention packages may result in a greater public health impact than single interventions. Understanding the separate impact of each component on the overall package effectiveness can improve intervention delivery.

METHODS

We adapted an approach to evaluate the effects of a time-varying intervention package in a network-randomized study. In some network-randomized studies, only a subset of participants in exposed networks receive the intervention themselves. The spillover effect contrasts average potential outcomes if a person was not exposed to themselves under intervention in the network versus no intervention in a control network. We estimated the effects of components of the intervention package in HIV Prevention Trials Network 037, a Phase III network-randomized HIV prevention trial among people who inject drugs and their risk networks using marginal structural models to adjust for time-varying confounding. The index participant in an intervention network received a peer education intervention initially at baseline, then boosters at 6 and 12 months. All participants were followed to ascertain HIV risk behaviors.

RESULTS

There were 560 participants with at least one follow-up visit, 48% of whom were randomized to the intervention, and 1,598 participant visits were observed. The spillover effect of the boosters in the presence of initial peer education training was a 39% rate reduction (rate ratio = 0.61; 95% confidence interval = 0.43, 0.87).

CONCLUSIONS

These methods will be useful for evaluating intervention packages in studies with network features.

Multilevel strategies to end HIV for young couples in Cape Town: Study protocol for a cluster randomized trial

This protocol presents a multilevel cluster randomized study in 24 communities in Cape Town, South Africa. The study comprises four specific aims. Aim 1, conducted during the formative phase, was to modify the original Couples Health CoOp (CHC) intervention to include antiretroviral therapy/pre-exposure prophylaxis (ART/PrEP), called the Couples Health CoOp Plus (CHC+), with review from our Community Collaborative Board and a Peer Advisory Board. Aim 1 has been completed for staging the trial. Aim 2 is to evaluate the impact of a stigma awareness and education workshop on community members' attitudes and behaviors toward young women and men who use AODs and people in their community seeking HIV services (testing/ART/PrEP) and other health services in their local clinics. Aim 3 is to test the efficacy of the CHC+ to increase both partners' PrEP/ART initiation and adherence (at 3 and 6 months) and to reduce alcohol and other drug use, sexual risk and gender-based violence, and to enhance positive gender norms and communication relative to HIV testing services (n = 480 couples). Aim 4 seeks to examine through mixed methods the interaction of the stigma awareness workshop and the CHC+ on increased PrEP and ART initiation, retention, and adherence among young women and their primary partners. Ongoing collaborations with community peer leaders and local outreach staff from these communities are essential for reaching the project's aims. Additionally, a manualized field protocol with regular training, fidelity checks, and quality assurance are critical components of this multilevel community trial for successful ongoing data collection. Trial registration. Clinicaltrials.gov Registration Number: NCT05310773. Pan African Trials: pactr.samrc.ac.za/ Registration Number: PACTR202205640398485.

Correlates of concordance between self-reported and lab-confirmed viral load among Black and Latine men who have sex with men (BLMSM) living with HIV in New York City

Sustained viral suppression is one of the four strategies in the U.S. Department of Health and Human Services' (HHS) plan to end the HIV epidemic in the United States. Individuals living with HIV must understand their viral load accurately for this strategy to be effective. We conducted cross-sectional analyses using baseline data from the NNHIV longitudinal study among men who have sex with men (MSM) living with HIV in New York City to identify factors associated with concordant knowledge between self-reported and lab-confirmed viral load. Of 164 Black and/or Latine participants, 67% (n = 110) reported that their viral load was undetectable, however lab tests showed only 44% (n = 72) had an undetectable viral load (<20 copies/ml). Overall, 62% of the sample (n = 102) had concordant HIV viral load knowledge (agreement of self-reported and lab viral load). In multivariable regression, those with unstable housing (PR = 0.52, 0.30-0.92) and those who had higher levels of beliefs of racism in medicine scale (PR = 0.76, 0.59-0.97) were less likely to have concordant knowledge. Our study underscores the need for implementing measures to improve viral load knowledge, U = U messaging, and strategies to achieve and maintain undetectable viral load status to reduce the burden of HIV at the population level.

Assessing Direct and Spillover Effects of Intervention Packages in Network-Randomized Studies

Intervention packages may result in a greater public health impact than single interventions. Understanding the separate impact of each component in the overall package effectiveness can improve intervention delivery. We adapted an approach to evaluate the effects of a time-varying intervention package in a network-randomized study. In some network-randomized studies, only a subset of participants in exposed networks receive the intervention themselves. The spillover effect contrasts average potential outcomes if a person was not exposed themselves under intervention in the network versus no intervention in a control network. We estimated effects of components of the intervention package in HIV Prevention Trials Network 037, a Phase III network-randomized HIV prevention trial among people who inject drugs and their risk networks using Marginal Structural Models to adjust for time-varying confounding. The index participant in an intervention network received a peer education intervention initially at baseline, then boosters at 6 and 12 months. All participants were followed to ascertain HIV risk behaviors. There were 560 participants with at least one follow-up visit, 48% of whom were randomized to the intervention, and 1,598 participant-visits were observed. The spillover effect of the boosters in the presence of initial peer education training was a 39% rate reduction (Rate Ratio = 0.61; 95% confidence interval= 0.43, 0.87). These methods will be useful to evaluate intervention packages in studies with network features.

Are All Gay Men at Risk of Developing HIV/AIDS? Why China's Mass HIV Testing Has Majorly Targeted Gay Men in the Era of Biomedicalization

Global HIV/AIDS responses have been increasingly biomedically dominated over the past years. In line with this shifting paradigm, China has prioritized mass HIV testing as a practical approach to controlling its HIV/AIDS epidemics among at-risk populations, especially gay men and other men who have sex with men (MSM). This study analyzed why China's mass HIV testing mainly targeted gay men by understanding the perspectives of public health professionals, community-based organization (CBO) workers, and gay men. In addition, this study revealed the tensions and unintended consequences of HIV/AIDS prevention and the representation of gay men in China. The study involved fieldwork conducted in a major city in Eastern China from 2015 to 2019. Semi-structured interviews were held with participants from the three abovementioned groups (N = 25). The study identified four processes concerning why gay men are mainly targeted for HIV testing. Some public health professionals believe that being a gay man is equivalent to having HIV/AIDS risks. In addition, this study particularly noted tensions between public health professionals and gay men, including gay men-identified CBO workers, over whether mass HIV testing should target gay men or anyone who engaged in sexual risk behaviors. This study argued that a particular focus on gay men due to pursuing biomedical advances in HIV/AIDS prevention seems to have unintendedly stereotyped gay men based on the presumptions that they are at risk of developing HIV/AIDS. In addition, this study corresponded to the broader social scientific discussion concerning whether HIV/AIDS intervention should target specific sexual risk practices or sexual identity/population.

An Automated Literature Review Tool (LiteRev) for Streamlining and Accelerating Research Using Natural Language Processing and Machine Learning: Descriptive Performance Evaluation Study

BACKGROUND

Literature reviews (LRs) identify, evaluate, and synthesize relevant papers to a particular research question to advance understanding and support decision-making. However, LRs, especially traditional systematic reviews, are slow, resource-intensive, and become outdated quickly.

OBJECTIVE

LiteRev is an advanced and enhanced version of an existing automation tool designed to assist researchers in conducting LRs through the implementation of cutting-edge technologies such as natural language processing and machine learning techniques. In this paper, we present a comprehensive explanation of LiteRev's capabilities, its methodology, and an evaluation of its accuracy and efficiency to a manual LR, highlighting the benefits of using LiteRev.

METHODS

Based on the user's query, LiteRev performs an automated search on a wide range of open-access databases and retrieves relevant metadata on the resulting papers, including abstracts or full texts when available. These abstracts (or full texts) are text processed and represented as a term frequency-inverse document frequency matrix. Using dimensionality reduction (pairwise controlled manifold approximation) and clustering (hierarchical density-based spatial clustering of applications with noise) techniques, the corpus is divided into different topics described by a list of the most important keywords. The user can then select one or several topics of interest, enter additional keywords to refine its search, or provide key papers to the research question. Based on these inputs, LiteRev performs a k-nearest neighbor (k-NN) search and suggests a list of potentially interesting papers. By tagging the relevant ones, the user triggers new k-NN searches until no additional paper is suggested for screening. To assess the performance of LiteRev, we ran it in parallel to a manual LR on the burden and care for acute and early HIV infection in sub-Saharan Africa. We assessed the performance of LiteRev using true and false predictive values, recall, and work saved over sampling.

RESULTS

LiteRev extracted, processed, and transformed text into a term frequency-inverse document frequency matrix of 631 unique papers from PubMed. The topic modeling module identified 16 topics and highlighted 2 topics of interest to the research question. Based on 18 key papers, the k-NNs module suggested 193 papers for screening out of 613 papers in total (31.5% of the whole corpus) and correctly identified 64 relevant papers out of the 87 papers found by the manual abstract screening (recall rate of 73.6%). Compared to the manual full text screening, LiteRev identified 42 relevant papers out of the 48 papers found manually (recall rate of 87.5%). This represents a total work saved over sampling of 56%.

CONCLUSIONS

We presented the features and functionalities of LiteRev, an automation tool that uses natural language processing and machine learning methods to streamline and accelerate LRs and support researchers in getting quick and in-depth overviews on any topic of interest.

Challenges and barriers to HIV care engagement and care cascade: viewpoint

Patients with human immunodeficiency virus (HIV) are subject to long-term management and a complex care process. Patients with HIV are clinically, socially, and emotionally vulnerable, face many challenges, and are often stigmatized. Healthcare providers should engage them with diligence in the HIV care cascade process. In this paper, we discuss from our viewpoint certain social and public health barriers and challenges that should be considered by healthcare providers to better engage patients in the HIV care cascade process and maximize its outcomes.

Biomedical bargains: Negotiating "safe sex" on antiretroviral treatment in rural South Africa

Wide-scale availability of antiretroviral treatment (ART) has transformed the global landscape for HIV prevention, shifting emphasis away from a strictly behavioral focus on changing sexual practices towards a biomedical approach. Successful ART management is measured by an undetectable viral load, which helps maintain overall health and prevent onward viral transmission. The latter utility of ART, however, must be understood in the context of its implementation. In South Africa, ART has become easily accessible - yet ART knowledge spreads unevenly, while counseling advice and normative expectations and experiences of gender and aging interact to inform sexual practices. As ART enters the sexual lives of middle-aged and older people living with HIV (MOPLH), a population growing rapidly, how has it informed sexual decisions and negotiations? Drawing on in-depth interviews with MOPLH on ART, corroborated with focus group discussions and national ART-related policies and guidelines, we find that for MOPLH, sexual decisions increasingly feature compliance with biomedical directives and concern for ART efficacy. Seeking consensus regarding the biological risks of sex on ART becomes an important feature of sexual negotiations, and anticipated disagreements can pre-empt sexual relationships altogether. We introduce the concept of biomedical bargains to explain what happens when disagreements arise, and the terms of sex are negotiated using competing interpretations of biomedical information. For both men and women, ostensibly gender-neutral biomedical discourses provide new discursive resources and strategies for sexual decisions and negotiations, yet biomedical bargains are still embedded in gender dynamics-women invoke the dangers of jeopardizing treatment efficacy and longevity to insist on condoms or justify abstinence, while men utilize biomedical arguments in an effort to render condomless sex safe. While the full therapeutic benefits of ART are critical for the efficacy and equity of HIV programs, they will nonetheless always affect, and be affected by, social life.

High-level dolutegravir resistance can emerge rapidly from few variants and spread by recombination: implications for integrase strand transfer inhibitor salvage therapy

The integrase strand transfer inhibitor (INSTI) dolutegravir is commonly used in combination antiretroviral therapy regimens and retains strong potency even with primary resistance mutations to some other INSTIs. Acquisition of accessory mutations to primary mutations results in significant increases in dolutegravir resistance. Previously, we reported that addition of the secondary mutation T97A can result in rapid treatment failure in individuals with INSTI mutations at positions 140 and 148. Here, we conducted a detailed case study of one of these individuals and find that T97A-containing HIV emerged from a large replicating population from only a few (≤4) viral lineages. When combined with primary INSTI resistance mutations, T97A provides a strong selective advantage; the finding that T97A-containing variants spread by replication and recombination, and persisted for months after discontinuing dolutegravir, has important implications as dolutegravir is rolled out worldwide.

HIV Testing Uptake According to Opt-In, Opt-Out or Risk-Based Testing Approaches: a Systematic Review and Meta-Analysis

Purpose of Review

Improving HIV testing uptake is essential to ending the HIV pandemic. HIV testing approaches can be opt-in, opt-out or risk-based. This systematic review examines and compares the uptake of HIV testing in opt-in, opt-out and risk-based testing approaches.

Recent Findings

There remain missed opportunities for HIV testing in a variety of settings using different approaches: opt-in (a person actively accepts to be tested for HIV), opt-out (a person is informed that HIV testing is routine/standard of care, and they actively decline if they do not wish to be tested for HIV) or risk-based (using risk-based screening tools to focus testing on certain individuals or sub-populations at greater risk of HIV). It is not clear how the approach could impact HIV test uptake when adjusted for other factors (e.g. rapid testing, country-income level, test setting and population tested).

Summary

We searched four databases for studies reporting on HIV test uptake. In total, 18,238 records were screened, and 150 studies were included in the review. Most studies described an opt-in approach (87 estimates), followed by opt-out (76) and risk-based (19). Opt-out testing was associated with 64.3% test uptake (I² = 99.9%), opt-in testing with 59.8% (I² = 99.9%) and risk-based testing with 54.4% (I² = 99.9%). When adjusted for settings that offered rapid testing, country income level, setting and population tested, opt-out testing had a significantly higher uptake (+ 12% (95% confidence intervals: 3–21), p = 0.007) than opt-in testing. We also found that emergency department patients and hospital outpatients had significantly lower HIV test uptake than other populations.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11904-022-00614-0.

Chronic Opioid Administration is Associated with Prevotella-dominated Dysbiosis in SIVmac251 Infected, cART-treated Macaques

People living with the human immunodeficiency virus (HIV) have an elevated risk of opioid misuse due to both prescriptions for HIV-associated chronic pain and because injection drug use remains a primary mode of HIV transmission. HIV pathogenesis is characterized by chronic immune activation and microbial dysbiosis, and translocation across the gut barrier exacerbating inflammation. Despite the high rate of co-occurrence, little is known about the microbiome during chronic opioid use in the context of HIV and combination antiretroviral therapy (cART). We recently demonstrated the reduction of the CD4 + T-cell reservoir in lymphoid tissues but increased in microglia/macrophage reservoirs in CNS by using morphine-treated, simian immunodeficiency virus (SIV)-infected rhesus macaques with viremia suppressed by cART. To understand whether morphine may perturb the gut-brain axis, fecal samples were collected at necropsy, DNA isolated, and 16S rRNA sequenced and changes of the microbiome analyzed. We found that morphine treatment led to dysbiosis, primarily characterized by expansion of Bacteroidetes, particularly Prevotellaceae, at the expense of Firmicutes and other members of healthy microbial communities resulting in a lower α-diversity. Of the many genera in Prevotellaceae, the differences between the saline and morphine group were primarily due to a higher relative abundance of Prevotella_9, the taxa most similar to Prevotella copri, an inflammatory pathobiont in the human microbiome. These findings reinforce previous research showing that opioid abuse is associated with dysbiosis, therefore, warranting additional future research to elucidate the complex interaction between the host and opioid abuse during HIV and SIV infection.

Girl Champ in eSwatini: A Strategic Marketing Campaign to Promote Demand for Sexual and Reproductive Health Services Among Young Women

Efforts to engage adolescent girls and young women (AGYW) in HIV services have struggled, in part, due to limited awareness of services and stigma. Strategic marketing is a promising approach, but the impact on youth behavior change is unclear. We report findings from a mixed methods evaluation of the Girl Champ campaign, designed to generate demand for sexual and reproductive services among AGYW, and piloted in three clinics in the Manzini region of eSwatini. We analyzed and integrated data from longitudinal, clinic-level databases on health service utilization among AGYW before and after the pilot, qualitative interviews with stakeholders responsible for the implementation of the pilot, and participant feedback surveys from attendees of Girl Champ events. Girl Champ was well received by most stakeholders based on event attendance and participant feedback, and associated with longitudinal improvements in demand for HIV services. Findings can inform future HIV demand creation interventions for youth.

Point-of-care CD4 testing: Differentiated care for the most vulnerable

Background

South Africa, with the highest burden of HIV infection globally, has made huge strides in its HIV/ART programme, but AIDS deaths have not decreased proportionally to ART uptake. Advanced HIV disease (CD4 < 200 cells/mm³) persists, and CD4 count testing is being overlooked since universal test-and-treat was implemented. Point-of-care CD4 testing could address this gap and assure differentiated care to these vulnerable patients with low CD4 counts.

Methods

A time randomised implementation trial was conducted, enrolling 603 HIV positive non-ART, not pregnant patients at a primary health care clinic in Durban, South Africa. Weeks were randomised to either point-of-care CD4 testing (n = 305 patients) or standard-of-care central laboratory CD4 testing (n = 298 patients) to assess the proportion initiating ART at 3 months. Cox regression, with robust standard errors adjusting for clustering by week, were used to assess the relationship between treatment initiation and arm.

Results

Among the 578 (299 point-of-care and 279 standard-of-care) patients eligible for analysis, there was no significant difference in the number of eligible patients initiating ART within 3 months in the point-of-care (73%) and the standard-of-care (68%) groups (P = 0.112). The time-to-treat analysis was not significantly different in patients with CD4 counts of 201-500 cells/mm³ which could have been due to appointment scheduling to cope with the large burden of cases. However, in patients with advanced HIV disease (CD4 < 200cells/mm³) 65% more patients started ART earlier in the point-of-care group (HR 1.65 (95% confidence interval (CI) = 0.99-2.75; P = 0.052) compared to the standard-of-care group.

Conclusions

Point-of-care testing decreased time-to-treatment in those with advanced HIV disease. With universal test and treat for HIV, rollout of simple point-of-care CD4 testing would ensure early diagnosis of advanced HIV disease and facilitate differentiated care for these vulnerable patients as per the World Health Organisation 2020 target product profile for point-of-care CD4 testing.

Trial registration

ISRCTN14220457.

Predicting, Diagnosing, and Treating Acute and Early HIV Infection in a Public Sector Facility in Eswatini

BACKGROUND

The lack of acute and early HIV infection (AEHI) diagnosis and care contributes to high HIV incidence in resource-limited settings. We aimed to assess the yield of AEHI, predict and diagnose AEHI, and describe AEHI care outcomes in a public sector setting in Eswatini.

SETTING

This study was conducted in Nhlangano outpatient department from March 2019 to March 2020.

METHODS

Adults at risk of AEHI underwent diagnostic testing for AEHI with the quantitative Xpert HIV-1 viral load (VL) assay. AEHI was defined as the detection of HIV-1 VL on Xpert and either an HIV-seronegative or HIV-serodiscordant third-generation antibody-based rapid diagnostic test (RDT) result. First, the cross-sectional analysis obtained the yield of AEHI and established a predictor risk score for the prediction of AEHI using Lasso logistic regression. Second, diagnostic accuracy statistics described the ability of the fourth-generation antibody/p24 antigen-based Alere HIV-Combo RDT to diagnose AEHI (vs Xpert VL testing). Third, we described acute HIV infection care outcomes of AEHI-positive patients using survival analysis.

RESULTS

Of 795 HIV-seronegative/HIV-serodiscordant outpatients recruited, 30 (3.8%, 95% confidence interval: 2.6% to 5.3%) had AEHI. The predictor risk score contained several factors (HIV-serodiscordant RDT, women, feeling at risk of HIV, swollen glands, and fatigue) and had sensitivity and specificity of 83.3% and 65.8%, respectively, to predict AEHI. The HIV-Combo RDT had sensitivity and specificity of 86.2% and 99.9%, respectively, to diagnose AEHI. Of 30 AEHI-positive patients, the 1-month cumulative treatment initiation was 74% (95% confidence interval: 57% to 88%), and the 3-month viral suppression (<1000 copies/mL) was 87% (67% to 98%).

CONCLUSION

AEHI diagnosis and care seem possible in resource-limited settings.

Brief Report: Impact of the COVID-19 Pandemic on Virological Suppression in People Living With HIV Attending a Large Italian HIV Clinic

BACKGROUND

We assessed the impact of the coronavirus disease 2019 (COVID-19) pandemic on HIV suppression rates in people living with HIV (PLWH) attending a large Italian HIV clinic.

SETTING

The HIV outpatient clinic of the Infectious Diseases Department of Luigi Sacco Hospital, Milan, Italy, which serves more than 5000 PLWH per year.

METHODS

A before and after quasi-experimental study design was used to make a retrospective assessment of the monthly trend of HIV-RNA determinations of ≥50 among the PLWH attending our clinic, with "before" being the period from January 1, 2016 to February 20, 2020, and "after" being the period from February 21, 2020 to December 31, 2020 (the COVID-19 period). Interrupted time series analysis was used to evaluate any changes in the trend.

RESULTS

During the study period, 70,349 HIV-RNA viral load determinations were made, and the percentage of HIV-RNA viral load determinations of <50 copies/mL increased from 88.4% in 2016 to 93.2% in 2020 (P < 0.0001). There was a significant monthly trend toward a decrease in the number of HIV-RNA determinations of ≥50 copies/mL before the pandemic (β -0.084; standard error 0.015; P < 0.001), and this did not significantly change after it started (β -0.039, standard error 0.161; P = 0.811).

CONCLUSIONS

A high prevalence of viral suppression was maintained among the PLWH referring to our clinic, despite the structural barriers raised by the COVID-19 pandemic. The use of simplified methods of delivering care (such as teleconsultations and multiple antiretroviral treatment prescriptions) may have contributed to preserving this continuum.

Expert stakeholder perspectives on the acceptability of treatment-as-prevention in prison: a qualitative substudy of the 'Surveillance and Treatment of Prisoners with Hepatitis C' project (SToP-C)

BACKGROUND AND AIMS

Mathematical modelling has demonstrated the theoretical feasibility of HCV treatment-as-prevention strategies in custodial settings, yet limited empirical data exists. The Australian 'Surveillance and Treatment of Prisoners with Hepatitis C' study is the world's first trial of hepatitis C virus (HCV) treatment-as-prevention in prison. This study aimed to analyse how expert stakeholders involved in the Australian HCV response assessed the acceptability of HCV treatment-as-prevention in prison using interview data from the SToP-C qualitative substudy.

DESIGN AND SETTING

Qualitative analysis using semi-structured interviews in Australia.

PARTICIPANTS

Nineteen key HCV experts.

MEASUREMENTS

Drawing upon Sekhon's theoretical framework of acceptability, data were organized thematically under four component constructs of acceptability: affective attitude; ethicality; opportunity costs; and perceived effectiveness.

FINDINGS

Most differences in participant assessments of acceptability were a matter of relative emphasis and prioritization rather than absolute polarity. Nonetheless, a small minority of participants was overtly critical of the approach. Arguing against the focus on treatment, they instead advocated for prevention-as-prevention, including the improvement and expansion of existing harm reduction measures.

CONCLUSIONS

Qualitative analysis of expert stakeholder assessments of the acceptability of hepatitis C virus treatment-as-prevention in Australian prisons found no opposition to the universal rollout of direct-acting anti-virals, but most voiced concern regarding the lack of effective primary prevention in Australian prisons.

Tandem bispecific antibody prevents pathogenic SHIVSF162P3CN infection and disease progression

Although progress has been made on constructing potent bi-specific broadly neutralizing antibody (bi-bNAb), few bi-bNAbs have been evaluated against HIV-1/AIDS in non-human primates (NHPs). Here, we report the efficacy of a tandem bi-bNAb, namely BiIA-SG, in Chinese-origin rhesus macaques (CRM) against the CRM-adapted R5-tropic pathogenic SHIV_SF162P3CN challenge. Pre-exposure BiIA-SG injection prevents productive viral infection in 6 of 6 CRMs with unmeasurable proviral load, T cell responses, and seroconversion. Single BiIA-SG injection, at day 1 or 3 post viral challenge, significantly reduces peak viremia, achieves undetectable setpoint viremia in 8 of 13 CRMs, and delays disease progression for years in treated CRMs. In contrast, 6 of 8 untreated CRMs develop simian AIDS within 2 years. BiIA-SG-induced long-term protection is associated with CD8⁺ T cells as determined by anti-CD8β antibody depletion experiments. Our findings provide a proof-of-concept that bi-bNAb treatment elicits T cell immunity in NHPs, which warrant the clinical development of BiIA-SG for HIV-1 prevention and immunotherapy.

Point-of-care and Near Real-time Testing for Antiretroviral Adherence Monitoring to HIV Treatment and Prevention

PURPOSE OF REVIEW

In this report, we review the need for point-of-care (POC) or near real-time testing for antiretrovirals, progress in the field, evidence for guiding implementation of these tests globally, and future directions in objective antiretroviral therapy (ART) or pre-exposure prophylaxis (PrEP) adherence monitoring.

RECENT FINDINGS

Two cornerstones to end the HIV/AIDS pandemic are ART, which provides individual clinical benefits and eliminates forward transmission, and PrEP, which prevents HIV acquisition with high effectiveness. Maximizing the individual and public health benefits of these powerful biomedical tools requires high and sustained antiretroviral adherence. Routine monitoring of medication adherence in individuals receiving ART and PrEP may be an important component in interpreting outcomes and supporting optimal adherence. Existing practices and subjective metrics for adherence monitoring are often inaccurate or unreliable and, therefore, are generally ineffective for improving adherence. Laboratory measures of antiretroviral concentrations using liquid chromatography tandem mass spectrometry have been utilized in research settings to assess medication adherence, although these are too costly and resource-intensive for routine use. Newer, less costly technologies such as antibody-based methods can provide objective drug-level measurement and may allow for POC or near-patient adherence monitoring in clinical settings. When coupled with timely and targeted counseling, POC drug-level measures can support adherence clinic-based interventions to ART or PrEP in near real time.

Integrating and Interpreting Findings from the Latest Treatment as Prevention Trials

PURPOSE OF REVIEW

In 2018-2019, studies were published assessing the effectiveness of reducing HIV incidence by expanding HIV testing, linkage to HIV treatment, and assistance to persons living with HIV to adhere to their medications (the "90-90-90" strategy). These tests of "treatment as prevention" (TasP) had complex results.

RECENT FINDINGS

The TasP/ANRS 12249 study in South Africa, the SEARCH study in Kenya and Uganda, and one comparison (arms A to C) of the HPTN 071 (PopART) study in South Africa and Zambia did not demonstrate a community impact on HIV incidence. In contrast, the Botswana Ya Tsie study and the second comparison (arms B to C) of PopART indicated significant ≈ 30% reductions in HIV incidence in the intervention communities where TasP was expanded. We discuss the results of these trials and outline future research and challenges. These include the efficient expansion of widespread HIV testing, better linkage to care, and viral suppression among all persons living with HIV. A top implementation science priority for the next decade is to determine what strategies to use in specific local contexts.

Implementation opportunities and challenges identified by key stakeholders in scaling up HIV Treatment as Prevention in British Columbia, Canada: a qualitative study

Background

The province of British Columbia (BC), Canada, was among the first jurisdictions to scale up HIV Treatment as Prevention (TasP) to the population level, including funding and policy commitments that enhanced HIV testing efforts (e.g., expansion of routine, opt-out testing), while also making antiretroviral therapy universally available to all people living with HIV. As such, BC represents a critical context within which to identify factors that influenced the scalability of TasP (e.g., acceptability, adoption, fidelity, equitable reach, sustainability), including key opportunities and challenges.

Methods

We draw on in-depth, semi-structured interviews with 10 key stakeholders, comprised policymakers at the local and provincial levels and representatives from community-based organizations. Using the Consolidated Framework for Implementation Research (CFIR) to guide data collection, coding, and analysis, we identified key factors that influenced practice transformation and scale up.

Results

Key factors that contributed to the successful scale up of TasP included: (i) opportunities that enhanced stakeholder buy-in based on features of the intervention characteristics, including with regard to assessments about the quality and strength of evidence supporting TasP; (ii) an inner setting implementation climate that was, in part, shaped by the large and highly symbolic government investments into TasP; (iii) features of the outer setting such as external policies (e.g., harm reduction) that cultivated opportunities to implement new "systems-level" approaches to HIV intervention; (iv) the personal attributes of some "middle-level" influencers, including a team that was comprised of some highly motivated and social justice-oriented individuals (e.g., folks who were deeply committed to serving marginalized populations); and (v) the capacity to develop various implementation processes that could maintain "nimble and evidence-informed" adaptations across a highly decentralized service delivery system, while also creating opportunities to adapt features of TasP programming based on "real time" program data.

Conclusion

Constructs across all five domains of CFIR (intervention characteristics, outer setting, inner setting, characteristics of individuals, and process) were identified to influence the success of TasP in BC. Our findings provide important insights into how BC can successfully implement and scale up other systems-level interventions that have demonstrated efficacy, while also offering insights for other jurisdictions that are currently or planning to scale up TasP.

Opportunities and Challenges in HIV Treatment as Prevention Research: Results from the ANRS 12249 Cluster-Randomized Trial and Associated Population Cohort

PURPOSE OF REVIEW

The ANRS 12249 treatment as prevention (TasP) trial investigated the impact of a universal test and treat (UTT) approach on reducing HIV incidence in one of the regions of the world most severely affected by the HIV epidemic-KwaZulu-Natal, South Africa. We summarize key findings from this trial as well as recent findings from controlled studies conducted in the linked population cohort quantifying the long-term effects of expanding ART on directly measured HIV incidence (2004-2017).

RECENT FINDINGS

The ANRS TasP trial did not-and could not-demonstrate a reduction in HIV incidence, because the offer of UTT in the intervention communities did not increase ART coverage and population viral suppression compared to the standard of care in the control communities. Ten controlled studies from the linked population cohort-including several quasi-experimental study designs-exploit heterogeneity in ART exposure to show a consistent and substantial impact of expanding provision of ART and population viral suppression on reduction in HIV incidence at the couple, household, community, and population levels. In this setting, all of the evidence from large, population-based studies (inclusive of the ANRS TasP trial) is remarkably coherent and consistent-i.e., higher ART coverage and population viral suppression were repeatedly associated with clear, measurable decreases in HIV incidence. Thus, the expanded provision of ART has plausibly contributed in a major way toward the dramatic 43% decline in population-level HIV incidence in this typical rural African population. The outcome of the ANRS TasP trial constitutes a powerful null finding with important insights for overcoming implementation challenges in the population delivery of ART. This finding does not imply lack of ART effectiveness in blocking onward transmission of HIV nor its inability to reduce HIV incidence. Rather, it demonstrates that large increases in ART coverage over current levels will require health systems innovations to attract people living with HIV in early stages of the disease to participate in HIV treatment. Such innovations and new approaches are required for the true potential of UTT to be realized.

The effect of 90-90-90 on HIV-1 incidence and mortality in eSwatini: a mathematical modelling study

Background

The rapid scale-up of antiretroviral therapy (ART) towards the UNAIDS 90-90-90 goals over the last decade has sparked considerable debate as to whether universal test and treat can end the HIV-1 epidemic in sub-Saharan Africa. We aimed to develop a network transmission model, calibrated to capture age-specific and sex-specific gaps in the scale-up of ART, to estimate the historical and future effect of attaining and surpassing the UNAIDS 90-90-90 treatment targets on HIV-1 incidence and mortality, and to assess whether these interventions will be enough to achieve epidemic control (incidence of 1 infection per 1000 person-years) by 2030.

Methods

We used eSwatini (formerly Swaziland) as a case study to develop our model. We used data on HIV prevalence by 5-year age bins, sex, and year from the 2007 Swaziland Demographic Health Survey (SDHS), the 2011 Swaziland HIV Incidence Measurement Survey, and the 2016 Swaziland Population Health Impact Assessment (PHIA) survey. We estimated the point prevalence of ART coverage among all HIV-infected individuals by age, sex, and year. Age-specific data on the prevalence of male circumcision from the SDHS and PHIA surveys were used as model inputs for traditional male circumcision and scale-up of voluntary medical male circumcision (VMMC). We calibrated our model using publicly available data on demographics; HIV prevalence by 5-year age bins, sex, and year; and ART coverage by age, sex, and year. We modelled the effects of five scenarios (historical scale-up of ART and VMMC [status quo], no ART or VMMC, no ART, age-targeted 90-90-90, and 100% ART initiation) to quantify the contribution of ART scale-up to declines in HIV incidence and mortality in individuals aged 15–49 by 2016, 2030, and 2050.

Findings

Between 2010 and 2016, status-quo ART scale-up among adults (aged 15–49 years) in eSwatini (from 34·0% in 2010 to 74·1% in 2016) reduced HIV incidence by 43·57% (95% credible interval 39·71 to 46·36) and HIV mortality by 56·17% (54·06 to 58·92) among individuals aged 15–49 years, with larger reductions in incidence among men and mortality among women. Holding 2016 ART coverage levels by age and sex into the future, by 2030 adult HIV incidence would fall to 1·09 (0·87 to 1·29) per 100 person-years, 1·42 (1·13 to 1·71) per 100 person-years among women and 0·79 (0·63 to 0·94) per 100 person-years among men. Achieving the 90-90-90 targets evenly by age and sex would further reduce incidence beyond status-quo ART, primarily among individuals aged 15–24 years (an additional 17·37% [7·33 to 26·12] reduction between 2016 and 2030), with only modest additional incidence reductions in adults aged 35–49 years (1·99% [–5·09 to 7·74]). Achieving 100% ART initiation among all people living with HIV within an average of 6 months from infection—an upper bound of plausible treatment effect—would reduce adult HIV incidence to 0·73 infections (0·55 to 0·92) per 100 person-years by 2030 and 0·46 (0·33 to 0·59) per 100 person-years by 2050.

Interpretation

Scale-up of ART over the last decade has already contributed to substantial reductions in HIV-1 incidence and mortality in eSwatini. Focused ART targeting would further reduce incidence, especially in younger individuals, but even the most aggressive treatment campaigns would be insufficient to end the epidemic in high-burden settings without a renewed focus on expanding preventive measures.

Funding

Global Good Fund and the Bill & Melinda Gates Foundation.