On-Demand Preexposure Prophylaxis in Men at High Risk for HIV-1 Infection

Strategies for achieving viral hepatitis C micro-elimination in the Netherlands

The Netherlands is striving to achieve national elimination of the hepatitis C virus (HCV) as one of the first countries worldwide. The favorable HCV epidemiology with both low prevalence and incidence, together with access to care and treatment, present excellent conditions to further build on towards this objective. The Dutch national plan on viral hepatitis, introduced in 2016, defines targets in the HCV healthcare cascade and provides a structural framework for the development of elimination activities. Since many different stakeholders are involved in HCV care in the Netherlands, focus has been placed on micro-elimination initiatives as a pragmatic and efficient approach. These numerous micro-eliminations projects have brought the Netherlands closer to HCV elimination. In the near future, efforts specifically have to be made in order to optimize case-finding strategies and to successfully accomplish the nationwide implementation of the registration and monitoring system of viral hepatitis mono-infections, before this final goal can be reached. The upcoming years will then elucidate if the Dutch' hands on approach has resulted in sufficient progress against HCV and if the Netherlands will lead the way towards nationwide HCV elimination.

Daily or on-demand oral tenofovir disoproxil fumarate/emtricitabine for HIV pre-exposure prophylaxis: experience from a hospital-based clinic in France

BACKGROUND

On-demand oral tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) has been approved for pre-exposure prophylaxis (PrEP) in MSM in France following the results of clinical studies, but data are limited on real-world experience.

DESIGN

A single-center, open-label, prospective cohort study that recruited people at high risk of HIV infection in Paris.

METHODS

Participants were enrolled in a single hospital-based outpatient clinic and were proposed to start PrEP with daily or on demand TDF/FTC. At baseline and every 3 months thereafter, patients were tested for HIV and creatinine plasma levels, and data on sexual behavior, other sexually transmitted infections (STIs), and tolerability were collected.

RESULTS

From 10 November 2015 to 30 April 2017, 1069 patients were screened and 1049 (98.1%) started PrEP. Median age was 36 years, 99.4% were MSM with a median number of partners of 10, and 793 (75.6%) opted for on demand PrEP. Over 486 person-years of follow-up, four HIV-infections were diagnosed in poorly or nonadherent patients (incidence 0.82/100 person-years). Rate of condomless sex at last intercourse increased from 53.3% at baseline to 79% at month 12 (P < 10), but increase in bacterial STI rates was modest (14.6% at baseline vs. 19.2% at month 12; P < 10). Most adverse events were gastrointestinal and did not lead to PrEP discontinuation.

CONCLUSIONS

Most PrEP users were high-risk MSM and opted for on-demand PrEP. PrEP use was associated with a low HIV incidence and a high rate of condomless sex with a modest increase in bacterial STIs.

Similar tenofovir hair concentrations in men and women after directly observed dosing of tenofovir disoproxil fumarate/emtricitabine: implications for preexposure prophylaxis adherence monitoring

OBJECTIVES

Women likely require higher adherence than men to preexposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) for similar efficacy. Pharmacologic metrics of adherence predict efficacy better than self-report, but expected drug levels (adherence benchmarks) must be established using directly observed therapy. We sought to evaluate whether tenofovir hair concentrations differ between women and men receiving directly observed TDF/FTC.

METHODS

We assessed tenofovir hair concentrations in HIV-uninfected volunteers randomized to receive 100%, 67%, or 33% of daily dosing of TDF/FTC for 12 weeks (DOT-DBS, NCT02022657). Hair samples were collected at dosing weeks 4, 8, and 12 and every 3 weeks during a 12-week washout. Tenofovir concentrations in the proximal 1.5 cm of hair (representing ∼6 weeks of exposure) were analyzed using liquid chromatography/tandem mass spectrometry. Linear regression was used to model tenofovir hair concentrations in terms of sex, doses over the prior 6 weeks, and number of days since last dose.

RESULTS

A total of 264 hair samples were analyzed from 23 female and 24 male participants. Female participants had similar tenofovir hair concentrations to men (estimated fold-difference 0.92, 95% CI 0.75-1.13, P = 0.43). The estimated fold-difference in tenofovir levels for female versus male participants did not appreciably change when age (0.93, 95% CI 0.76-1.15), weight (0.89, 95% CI 0.71-1.11), or race/ethnicity (0.95, 95% CI 0.77-1.17) were added to the model.

CONCLUSION

Women and men have similar adherence benchmarks for tenofovir in hair samples. As pharmacokinetic metrics are increasingly used for PrEP monitoring, these findings provide guidance for assessing adherence via hair concentrations.

Knowledge and use of HIV pre-exposure prophylaxis among men who have sex with men in Berlin - A multicentre, cross-sectional survey

Background

HIV pre-exposure prophylaxis (PrEP) has likely contributed to large decreases in HIV incidence among men who have sex with men (MSM) in several major cities. Berlin has seen a smaller decline, and affordable PrEP has been accessible through formal channels in Germany only since autumn 2017. We aimed to investigate knowledge and use of PrEP among MSM in Berlin, and factors predictive of a desire to use PrEP and history of PrEP use.

Methods

Multicentre, paper-based, self-administered survey of adult MSM whose HIV status was negative or unknown at time of participation. Data were collected from 1 October 2017 to 2 April 2018.

Results

473 of 875 questionnaires were returned (response rate 54.1%; mean age 37.4 years, range 18–79). 90.0% of participants were aware of PrEP and, of these, 48.2% felt well informed about it. Among the 17.2% of participants reporting PrEP use, 59.3% indicated obtaining some or all of it from informal sources. 23.7% of those with no history of PrEP use reported having condomless anal intercourse (CAI) with two or more partners over the past six months. Worries about side effects, cost, not having a doctor who prescribes it, and a lack of information were the most frequently reported barriers to PrEP use. A desire to use PrEP and history of PrEP use were associated in our multivariable model with having multiple CAI partners. A history of PrEP use was associated with having a university degree, one or two parents born outside Germany, or friends living with HIV.

Conclusions

We found high awareness of PrEP among MSM in Berlin, but also a strong need for more education on its pros, cons and proper use. The frequency of informal PrEP use was also high, raising urgent individual and public health concerns. Policy makers need to consider recent calls to improve access to PrEP and PrEP education through regular health services.

Efficacy and Safety of Oral TDF-Based Pre-exposure Prophylaxis for Men Who Have Sex With Men: A Systematic Review and Meta-Analysis

Background: Pre-exposure prophylaxis (PrEP) is used as an HIV prevention method by people at substantial risk of HIV infection. This systematic review and meta-analysis evaluates current clinical evidence for use of oral TDF-based PrEP among men who have sex with men.

Methods: A comprehensive literature search in PubMed, web of science, Google Scholar and ClinicalTrials.gov was performed. A random-effects meta-analysis was conducted using the event rate (ER) for estimation of the incidence of HIV and grade 3 or 4 adverse events (AE) among PrEP arm and using risk ratio (RR) for comparison of incidence of HIV and grade 3 or 4 AE between PrEP recipients and PrEP non-users. Blood-based adherence levels were also divided into three categories with reference to previous meta-analysis. Subgroup meta-analysis was also performed to evaluate whether blood-based adherence levels moderated the effect of TDF-based PrEP on HIV incidence. Narrative review was used due to inconsistent measurements of risk behavior and drug resistance. This review is registered on the PROSPERO database (CRD42017077965).

Results: Fourteen studies were included in the review. Oral TDF-based PrEP significantly reduced HIV incidence with minimum drug resistance and tolerable safety risks (HIV incidence, ER = 1.1%, 95% CI 0.6–2.0%, p < 0.001, RR = 0.244, 95% CI 0.111–0.537, p < 0.001 and grade 3 or 4 AEs, ER = 13.0%, 95% CI 9.9–16.9%, p < 0.001, RR = 1.059, 95% CI 0.824–1.362, p = 0.653). Oral TDF-based PrEP was more effective in reducing HIV incidence with high levels of blood-based PrEP adherence (ER, 0.4%) compared to moderate adherence (2.9%; p < 0.001). Most studies found no association between PrEP use and self-reported sexual behavior.

Conclusion: Oral TDF-based PrEP is an effective intervention to prevent against HIV infection among MSM. Well-designed implementation science studies that integrate sociobehavioral and biomedical interventions are needed to identify optimal PrEP delivery models in different populations to translate biomedical efficacy into real-world efficacy.

Safety and pharmacokinetics of single, dual, and triple antiretroviral drug formulations delivered by pod-intravaginal rings designed for HIV-1 prevention: A Phase I trial

BACKGROUND

Intravaginal rings (IVRs) for HIV pre-exposure prophylaxis (PrEP) theoretically overcome some adherence concerns associated with frequent dosing that can occur with oral or vaginal film/gel regimens. An innovative pod-IVR, composed of an elastomer scaffold that can hold up to 10 polymer-coated drug cores (or "pods"), is distinct from other IVR designs as drug release from each pod can be controlled independently. A pod-IVR has been developed for the delivery of tenofovir (TFV) disoproxil fumarate (TDF) in combination with emtricitabine (FTC), as daily oral TDF-FTC is the only Food and Drug Administration (FDA)-approved regimen for HIV PrEP. A triple combination IVR building on this platform and delivering TDF-FTC along with the antiretroviral (ARV) agent maraviroc (MVC) also is under development.

METHODOLOGY AND FINDINGS

This pilot Phase I trial conducted between June 23, 2015, and July 15, 2016, evaluated the safety, pharmacokinetics (PKs), and acceptability of pod-IVRs delivering 3 different ARV regimens: 1) TDF only, 2) TDF-FTC, and 3) TDF-FTC-MVC over 7 d. The crossover, open-label portion of the trial (N = 6) consisted of 7 d of continuous TDF pod-IVR use, a wash-out phase, and 7 d of continuous TDF-FTC pod-IVR use. After a 3-mo pause to evaluate safety and PK of the TDF and TDF-FTC pod-IVRs, TDF-FTC-MVC pod-IVRs (N = 6) were evaluated over 7 d of continuous use. Safety was assessed by adverse events (AEs), colposcopy, and culture-independent analysis of the vaginal microbiome (VMB). Drug and drug metabolite concentrations in plasma, cervicovaginal fluids (CVFs), cervicovaginal lavages (CVLs), and vaginal tissue (VT) biopsies were determined via liquid chromatographic-tandem mass spectrometry (LC-MS/MS). Perceptibility and acceptability were assessed by surveys and interviews. Median participant age was as follows: TDF/TDF-FTC group, 26 y (range 24-35 y), 2 White, 2 Hispanic, and 2 African American; TDF-FTC-MVC group, 24.5 y (range 21-41 y), 3 White, 1 Hispanic, and 2 African American. Reported acceptability was high for all 3 products, and pod-IVR use was confirmed by residual drug levels in used IVRs. There were no serious adverse events (SAEs) during the study. There were 26 AEs reported during TDF/TDF-FTC IVR use (itching, discharge, discomfort), with no differences between TDF alone or in combination with FTC observed. In the TDF-FTC-MVC IVR group, there were 12 AEs (itching, discharge, discomfort) during IVR use regardless of attribution to study product. No epithelial disruption/thinning was seen by colposcopy, and no systematic VMB shifts were observed. Median (IQR) tenofovir diphosphate (TFV-DP) tissue concentrations of 303 (277-938) fmol/10(6) cells (TDF), 289 (110-603) fmol/10(6) cells (TDF-FTC), and 302 (177.1-823.8) fmol/10(6) cells (TDF-FTC-MVC) were sustained for 7 d, exceeding theoretical target concentrations for vaginal HIV prevention. The study's main limitations include the small sample size, short duration (7 d versus 28 d), and the lack of FTC triphosphate measurements in VT biopsies.

CONCLUSIONS

An innovative pod-IVR delivery device with 3 different formulations delivering different regimens of ARV drugs vaginally appeared to be safe and acceptable and provided drug concentrations in CVFs and tissues exceeding concentrations achieved by highly protective oral dosing, suggesting that efficacy for vaginal HIV PrEP is achievable. These results show that an alternate, more adherence-independent, longer-acting prevention device based on the only FDA-approved PrEP combination regimen can be advanced to safety and efficacy testing.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02431273.

Old Pathogen, New Challenges: A Narrative Review of the Multilevel Drivers of Syphilis Increasing in American Men Who Have Sex With Men

Since the turn of the current century, syphilis incidence and prevalence have been increasing more rapidly among men who have sex with men (MSM) than any other US subpopulation, exceeding their previously high rates in the 1970s and 1980s, before the AIDS epidemic. The reasons for these trends are multifactorial and complex, involving individual behavioral, sociocultural, structural, and biological factors, which will be reviewed in this article. Men who have sex with men tend to have more sexual partners than heterosexuals, and engage in practices (e.g., anal sex) that are highly efficient for syphilis transmission and nondetection of primary chancres. In the era of highly active antiretroviral therapy rendering adherent patients noninfectious and the use of preexposure prophylaxis, there is substantially less concern about HIV transmission and acquisition among MSM, resulting in higher levels of condomless sex. The increased concentration of syphilis among black MSM is partially related to assortative mixing, that is, black MSM being more likely to have other black sex partners, as well as decreased access to preventive services and treatment due to economic marginalization, Societal rejection and discrimination may also potentiate factors that may increase sexual risks resulting in syphilis, for example, depression and substance use. The anticipation of experiencing homophobic discrimination in health care settings may lead many sexually active MSM to delay needed screening and treatment, thus being infectious to partners for longer periods than other populations. To effectively control the syphilis epidemic among MSM, scaling up a combination of programs, ranging from enhanced community education to training clinicians and health care systems to provide culturally competent care, will be necessary.

Building the Case for Localized Approaches to HIV: Structural Conditions and Health System Capacity to Address the HIV/AIDS Epidemic in Six US Cities

Since the discovery of the secondary preventive benefits of antiretroviral therapy, national and international governing bodies have called for countries to reach 90% diagnosis, ART engagement and viral suppression among people living with HIV/AIDS. The US HIV epidemic is dispersed primarily across large urban centers, each with different underlying epidemiological and structural features. We selected six US cities, including Atlanta, Baltimore, Los Angeles, Miami, New York, and Seattle, with the objective of demonstrating the breadth of epidemiological and structural differences affecting the HIV/AIDS response across the US. We synthesized current and publicly-available surveillance, legal statutes, entitlement and discretionary funding, and service location data for each city. The vast differences we observed in each domain reinforce disparities in access to HIV treatment and prevention, and necessitate targeted, localized strategies to optimize the limited resources available for each city's HIV/AIDS response.

Interest in HIV pre-exposure prophylaxis in men who have sex with men in West Africa (CohMSM ANRS 12324 - Expertise France)

OBJECTIVE

To explore the interest in taking PrEP among Western African men who have sex with men (MSM).

METHODS

A cross-sectional survey was implemented at enrolment of HIV-negative MSM in a multiple centre community-based cohort study in four West African countries (Mali, Côte d'Ivoire, Burkina Faso, Togo). A standardised face-to-face questionnaire collected data on socio-demographic and behavioural characteristics over the previous 6 months. Descriptive analysis and multivariate logistic regression helped identify factors associated with the interest in taking PrEP.

RESULTS

Of 564 participants, 87% were interested in taking PrEP. Interest in PrEP was associated with inconsistent condom use for anal sex (adjusted odds ratio (aOR): 2.11; 95% confidence interval (CI) 1.21-3.67), transactional sex (aOR: 2.02; 95% CI 1.11-3.71), searching for male sexual partners on the Internet in the previous month (aOR: 1.86; 95% CI 1.01-3.43), having a high level of self-esteem (aOR: 1.20; 95% CI 1.06-1.36), having at least one sexually transmitted infections at enrolment (aOR: 5.08; 95% CI 1.40-18.4) and not being aware of PrEP (aOR: 2.03; 95% CI 1.04-3.96). Participants having sex with HIV-positive male partners (aOR: 0.28; 95% CI 0.11-0.74), those being more sexually attracted to women than to men (aOR: 0.20; 95% CI 0.07-0.89) and those reporting psychological and material support from close friends (aOR: 0.33; 95% CI 0.15-0.73) were less interested in taking PreP.

CONCLUSIONS

Western African HIV-negative MSM appear very interested in taking PrEP, especially those most at risk of HIV infection. PrEP implementation in a comprehensive prevention package should be considered urgently.

PCR-based rapid diagnostic tests as a strategy for preventing infections with sexually transmitted diseases-a 'diagnostics-as-prevention' modelling approach

The potential was modelled of molecular rapid diagnostic tests (RDTs) that target agents of sexually transmitted diseases (STDs) to contribute to a reduction in the exposure risk for sexually active populations who prefer condom-free high-risk contacts. The biostatistical approach is exemplified by considering the use of a PCR-based RDT for Chlamydia trachomatis and Neisseria gonorrhoeae in a population of German men having sex with men. We modelled the exposure risk as risk of sexual contact with individuals infected by a STD in spite of multiple RDTs having been conducted to identify STDs that could lead to avoidance of an infectious sexual contact. The risk for a given specific disease is influenced by the diagnostic accuracy of all diagnostic tests conducted. The simulation showed a reduction in exposure risk through conducting the selected PCR-based RDT as a strategy to prevent infections with C. trachomatis and N. gonorrhoeae in comparison with unprotected sexual contact of >97% for C. trachomatis and ≥96% for N. gonorrhoeae. Reliable knowledge of the performance characteristics of the diagnostic tests applied is essential for a thorough risk assessment based on such diagnostic approaches.

SIGNIFICANCE AND IMPACT OF THE STUDY

A low-threshold use of molecular rapid diagnostic tests in settings where risky sexual activity is undertaken with deliberate non-use of condoms is modelled. Such an approach might contribute to a considerable reduction in the exposure risk if positively tested individuals are excluded from unprotected sexual intercourse. Protective effects are influenced by the prevalence of the disease and the performance characteristics of the applied tests. Precise knowledge of the performance characteristics of the test assays employed are prerequisites of a reliable risk assessment. The modelling approach is of particular use for preventive health experts.

HIV

The benefits of combination antiretroviral therapy (cART) for HIV replication and transmission control have led to its universal recommendation. Many people living with HIV are, however, still undiagnosed or diagnosed late, especially in sub-Saharan Africa, where the HIV disease burden is highest. Further expansion in HIV treatment options, incorporating women-centred approaches, is essential to make individualised care a reality. With a longer life expectancy than before, people living with HIV are at an increased risk of developing non-AIDS comorbidities, such as cardiovascular diseases and cancers. Antiretroviral strategies are evolving towards a decrease in drug burden, and some two-drug combinations have proven efficacy for maintenance therapy. Investigational immune checkpoint inhibitors and broadly neutralising antibodies with effector functions have energised the HIV cure research field as the search for an effective vaccine continues. In this Seminar, we review advances and challenges relating to the goal of an AIDS-free world.

DIY HIV prevention: Formative qualitative research with men who have sex with men who source PrEP outside of clinical trials

Pre-exposure prophylaxis (PrEP) with antiretroviral medication is an effective, evidence-based option for HIV prevention. In England, issues of cost-effectiveness and of responsibility for commissioning prevention services have so far led National Health Service (NHS) England to decide not to commission PrEP. Given the significant lag between the awareness of PrEP efficacy and the opportunity to obtain PrEP through traditional health care routes, many gay and other men who have sex with men (MSM) have turned to ‘DIY PrEP’, purchasing generic formulations of PrEP for themselves on the internet or via other alternative routes. However, there is very little research on DIY PrEP practices and no qualitative study with DIY PrEP users in the UK. A formative qualitative study was conducted in 2017 to inform the development of an intervention (PrEP Club) to support DIY PrEP users and improve the safety and experience of this prevention strategy. Focus groups were held with 20 MSM who are based in London and are obtaining PrEP through means other than clinical trials, to explore their accounts of sourcing and using PrEP and the experiential meanings of these. In this article, we report findings from this first, formative study and present the different practices involved in finding out about PrEP, buying it and ascertaining legitimacy of sellers and products. We reflect on the uncertainties participants described related to actually using PrEP, including deciding on drug dosing and monitoring their health. Finally, we present the results of the discussions participants had about the kind of support they had received, the help they would have liked, and their views on proposed interventions to support DIY PrEP users, such as PrEP Club.

Acceptability of Injectable and On-Demand Pre-Exposure Prophylaxis Among an Online Sample of Young Men Who Have Sex with Men in California

PURPOSE

Pre-exposure prophylaxis (PrEP) is an effective strategy to prevent HIV. However, low uptake of daily oral PrEP since Food and Drug Administration approval and low medication adherence among users have stimulated the investigation of other modalities for delivery, such as injectable PrEP and on-demand PrEP. The objective of this study was to determine the demographic and behavioral predictors of willingness to try alternative PrEP delivery mechanisms among young men who have sex with men (YMSM) who stated that they were unwilling to try daily oral PrEP.

METHODS

YMSM in California were recruited through geosocial networking applications; we analyzed a subsample who stated that they were either ambivalent about trying or unwilling to try daily oral PrEP (n = 265). We used chi-square and Fisher's exact tests to determine characteristics associated with willingness to try injectable PrEP, willingness to try on-demand PrEP, and willingness to try either alternative form.

RESULTS

For individuals who stated that they would not be willing to try daily oral PrEP, ∼85% were willing to try on-demand and/or injectable PrEP. Individuals who reported some college or more reported greater willingness to try injectable PrEP (adjusted odds ratio [aOR]: 2.92; 95% confidence interval [CI]: 1.32-6.46), on-demand PrEP (aOR: 2.28; 95% CI: 1.06-4.90), or either method (aOR: 5.54; 95% CI: 1.78-17.22).

CONCLUSION

Future research should determine how to enhance uptake of emerging forms of PrEP among the individuals most at risk for HIV.

Behavioural and demographic correlates of undiagnosed HIV infection in a MSM sample recruited in 13 European cities

Background

Reducing the number of people with undiagnosed HIV infection is a major goal of HIV control and prevention efforts in Europe and elsewhere. We analysed data from a large multi-city European bio-behavioural survey conducted among Men who have Sex with Men (MSM) for previously undiagnosed HIV infections, and aimed to characterise undiagnosed MSM who test less frequently than recommended.

Methods

Data on sexual behaviours and social characteristics of MSM with undiagnosed HIV infection from Sialon II, a bio-behavioural cross-sectional survey conducted in 13 European cities in 2013/2014, were compared with HIV-negative MSM. Based on reported HIV-testing patterns, we distinguished two subgroups: MSM with a negative HIV test result within 12 months prior to the study, i.e. undiagnosed incident infection, and HIV positive MSM with unknown onset of infection. Bivariate and multivariate associations of explanatory variables were analysed. Distinct multivariate multi-level random-intercept models were estimated for the entire group and both subgroups.

Results

Among 497 participants with HIV-reactive specimens, 234 (47.1%) were classified as previously diagnosed, 106 (21.3%) as incident, and 58 (11.7%) as unknown onset based on self-reported status and testing history. MSM with incident HIV infection were twice as likely (odds ratio (OR) = 2.22, 95% confidence interval (95%CI): 1.17–4.21) to have used recreational substances during their last anal sex encounter and four times more likely (OR = 3.94, 95%CI: 2.14–7.27) not to discuss their HIV status with the last anal sex partner(s). MSM with unknown onset of HIV infection were 3.6 times more likely (OR = 3.61, 95%CI: 1.74–7.50) to report testing for a sexually transmitted infection (STI) during the last 12 months.

Conclusions

Approximately one third of the study participants who are living with HIV were unaware of their infection. Almost two-third (65%) of those with undiagnosed HIV appeared to have acquired the infection recently, emphasizing a need for more frequent testing. Men with the identified behavioural characteristics could be considered as primary target group for HIV Pre-Exposure Prophylaxis (PrEP) to avoid HIV infection. The increased odds of those with unknown onset of HIV infection to have had an STI test in the past year strongly suggests a lost opportunity to offer HIV testing.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3249-8) contains supplementary material, which is available to authorized users.

Transcutaneously refillable nanofluidic implant achieves sustained level of tenofovir diphosphate for HIV pre-exposure prophylaxis

Pre-exposure prophylaxis (PrEP) with antiretroviral (ARV) drugs are effective at preventing human immunodeficiency virus (HIV) transmission. However, implementation of PrEP presents significant challenges due to poor user adherence, low accessibility to ARVs and multiple routes of HIV exposure. To address these challenges, we developed the nanochannel delivery implant (NDI), a subcutaneously implantable device for sustained and constant delivery of tenofovir alafenamide (TAF) and emtricitabine (FTC) for HIV PrEP. Unlike existing drug delivery platforms with finite depots, the NDI incorporates ports allowing for transcutaneous refilling upon drug exhaustion. NDI-mediated drug delivery in rhesus macaques resulted in sustained release of both TAF and FTC for 83 days, as indicated by concentrations of TAF, FTC and their respectively metabolites in plasma, PBMCs, rectal mononuclear cells and tissues associated with HIV transmission. Notably, clinically relevant preventative levels of tenofovir diphosphate were achieved as early as 3 days after NDI implantation. We also demonstrated the feasibility of transcutaneous drug refilling to extend the duration of PrEP drug delivery in NHPs. Overall, the NDI represents an innovative strategy for long-term HIV PrEP administration in both developed and developing countries.

University of North Carolina/Emory Center for Innovative Technology (iTech) for Addressing the HIV Epidemic Among Adolescents and Young Adults in the United States: Protocol and Rationale for Center Development

Background

Over a fifth of all new HIV infections in the United States occur among persons aged 13 24 years, with most of these diagnoses occurring among gay and bisexual males (81%). While the epidemic of HIV in the United States has leveled off for many age groups, the annual number of new HIV diagnoses among young men who have sex with men (YMSM; 13-24 years old) remains high. Traditional approaches to continuum improvement for youth have been insufficient, and targeted interventions are urgently needed for young people at risk for or infected with HIV. Interventions delivered through mobile health technology represent a promising approach for improving outcomes in this population. Mobile phones have nearly reached saturation among youth, making mobile technology a particularly promising tool for reaching this population.

Objective

The University of North Carolina/Emory Center for Innovative Technology (iTech) is a National Institutes of Health cooperative agreement as part of the Adolescent Medicine Trials Network for HIV/AIDS Interventions. iTech aims to impact the HIV epidemic by conducting innovative, interdisciplinary research on technology-based interventions across the HIV prevention and care continuum for adolescents and young adults in the United States, particularly YMSM, by providing the following: (1) evaluation of novel approaches to identifying youth with undiagnosed HIV infections; (2) evaluation of multilevel, combination prevention approaches, particularly relevant to gender- and sexual-minority youth facing co-occurring health risks; (3) evaluation of uptake of and adherence to biomedical prevention modalities; and 4) evaluation of interventions designed to promote or optimize engagement in care and antiretroviral therapy adherence in HIV-positive youth, to optimize viral load suppression.

Methods

iTech brings together multidisciplinary experts in the fields of adolescent HIV treatment and prevention, development and evaluation of technology-based interventions, HIV surveillance and epidemiology, and intervention design and evaluation. This initiative will support 8 efficacy trials and 2 exploratory projects, each led by 2 principal investigators. Taken together, the studies address all of the key steps of the HIV prevention and care continuum for youth in the United States. Each proposal uses technology in a scientifically rigorous and innovative way to access, engage, and impact at-risk or infected youth. Nine iTech subject recruitment venues are spread across 8 US cities. Three cores (management, analytic, and technology) support all iTech activities and form the research network’s infrastructure, facilitating all aspects of study implementation and evaluation.

Results

Formative work has already begun on many of the above-mentioned iTech trials. We expect the first randomized controlled trials to begin in mid-2018. Additional details can be found in the individual intervention protocol papers in this issue.

Conclusions

Through its comprehensive research portfolio, iTech aims to effectively advance HIV prevention and care for youth through technology-based, youth-relevant interventions that maximize adaptability and sustainability.

Registered Report Identifier

RR1-10.2196/10365

Weighing the Evidence of Efficacy of Oral PrEP for HIV Prevention in Women in Southern Africa

As oral tenofovir-based regimens for preexposure prophylaxis (PrEP) are adopted as standard of care for HIV prevention, their utilization in clinical trials among women in southern Africa will require an accurate estimate of oral PrEP efficacy in this population. This information is critical for women in choosing this prevention strategy, and in public health policy making. Estimates of the efficacy of oral PrEP regimens containing tenofovir have varied widely across trials that enrolled women, with some studies reporting high efficacy and others reporting no efficacy. Although poor adherence is strongly associated with lack of efficacy, other factors, such as mode of transmission (sexual vs. parenteral), predominant HIV subtype (C vs. non-C), intensity of exposure, and percentage of stable serodiscordant couples, may also contribute to the variation in efficacy estimates. In this article, we evaluate the evidence for PrEP efficacy in women and propose potential explanations for the observed differences in efficacy among studies. Our review emphasizes the need to continue to refine estimates of efficacy and effectiveness of tenofovir-based oral PrEP so as to best develop the next generation of HIV prevention tools, and to inform public policies directed toward HIV prevention.

How Do Gay and Bisexual Men Make Up for Missed PrEP Doses, and What Impact Does Missing a Dose Have on Their Subsequent Sexual Behavior?

HIV pre-exposure prophylaxis (PrEP) is being adopted by members of key populations, such as gay and bisexual men (GBM). Since adherence to a daily PrEP regimen ensures a maximum protection, it is critical to understand GBM's behavioral responses to having missed PrEP doses. We report on qualitative interviews with GBM taking PrEP. We identified three behavioral responses: (1) 59% continued with their next scheduled dose; (2) 49% described "making up" for a missed dose by taking medication as soon as possible; and (3) 11% reported "doubling" the next PrEP dose. Participants provided potentially contradictory narratives about their sexual behavior after a missed dose: (1) 54% described making no changes; (2) 49% described adjusting their sexual behavior to reduce HIV risk; and (3) 10% said their decision would be contingent upon how many doses were missed. For PrEP prescribers, our data provide a useful lens to understand patients' lived experiences with PrEP.

"It's Like Birth Control for HIV": Communication and Stigma for Gay Men on PrEP

This study focuses on how gay men communicate about pre-exposure prophylaxis (PrEP), focusing on how they learned about PrEP, how they discussed adoption with health care providers, and to what extent they have encountered stigma on social networks. In this qualitative study, 39 gay PrEP users were interviewed about PrEP. A majority of the participants learned about PrEP via friends and potential sex partners, and a majority of the participants experienced stigma from their health care provider and from other gay men online, mainly referring to promiscuity and risks of STIs. The authors recommend that health care providers should be trained in minimizing the expression of stigmatizing attitudes and should increase their knowledge of PrEP.

Antiretroviral Drugs for Treatment and Prevention of HIV Infection in Adults: 2018 Recommendations of the International Antiviral Society-USA Panel

Importance

Antiretroviral therapy (ART) is the cornerstone of prevention and management of HIV infection.

Objective

To evaluate new data and treatments and incorporate this information into updated recommendations for initiating therapy, monitoring individuals starting therapy, changing regimens, and preventing HIV infection for individuals at risk.

Evidence Review

New evidence collected since the International Antiviral Society-USA 2016 recommendations via monthly PubMed and EMBASE literature searches up to April 2018; data presented at peer-reviewed scientific conferences. A volunteer panel of experts in HIV research and patient care considered these data and updated previous recommendations.

Findings

ART is recommended for virtually all HIV-infected individuals, as soon as possible after HIV diagnosis. Immediate initiation (eg, rapid start), if clinically appropriate, requires adequate staffing, specialized services, and careful selection of medical therapy. An integrase strand transfer inhibitor (InSTI) plus 2 nucleoside reverse transcriptase inhibitors (NRTIs) is generally recommended for initial therapy, with unique patient circumstances (eg, concomitant diseases and conditions, potential for pregnancy, cost) guiding the treatment choice. CD4 cell count, HIV RNA level, genotype, and other laboratory tests for general health and co-infections are recommended at specified points before and during ART. If a regimen switch is indicated, treatment history, tolerability, adherence, and drug resistance history should first be assessed; 2 or 3 active drugs are recommended for a new regimen. HIV testing is recommended at least once for anyone who has ever been sexually active and more often for individuals at ongoing risk for infection. Preexposure prophylaxis with tenofovir disoproxil fumarate/emtricitabine and appropriate monitoring is recommended for individuals at risk for HIV.

Conclusions and Relevance

Advances in HIV prevention and treatment with antiretroviral drugs continue to improve clinical management and outcomes for individuals at risk for and living with HIV.

Metabolic Effects of Preexposure Prophylaxis With Coformulated Tenofovir Disoproxil Fumarate and Emtricitabine

Background

Antiretroviral drugs have been associated with changes in lipids, fat mass and dat distribution. Tenofovir disoproxil fumarate (TDF) has been shown to have a more favorable metabolic profile than other drugs in its class. However, the metabolic effects of TDF in preexposure prophylaxis (PrEP) are unknown.

Methods

We evaluated the effects of TDF/emtricitabine (FTC) on lipids and body composition in a blinded, placebo-controlled PrEP trial. Participants enrolled in a metabolic subcohort (N = 251, TDF/FTC; N = 247, placebo) consented to fasting lipid panels, dual-energy X-ray absorptiometry scans for body composition, and pharmacologic testing of drug metabolites at baseline and every 24 weeks thereafter.

Results

Lean body mass was stable and unaffected by TDF/FTC. Body weight increased in both groups but was lower on TDF/FTC through week 72. This difference was explained by lower fat accumulation on TDF/FTC. The net median percent difference (standard error, P value) for TDF/FTC vs placebo at week 24 was -0.8% (0.4%, P = .02), +0.3% (0.4%, P = .46), and -3.8% (1.4%, P = .009) for total, lean, and fat mass, respectively. There was no apparent differential regional fat accumulation on TDF/FTC. Decreases in cholesterol, but not triglycerides, were seen in TDF/FTC participants, with detectable drug levels compared to placebo.

Conclusions

TDF/FTC for PrEP showed cholesterol reductions and appeared to transiently suppress the accumulation of weight and body fat compared to placebo. There was no evidence of altered fat distribution or lipodystrophy during daily oral TDF/FTC PrEP.

Clinical Trials Registration

NCT00458393.

Change in sexual risk behaviour after 6 months of pre-exposure prophylaxis use: results from the Amsterdam pre-exposure prophylaxis demonstration project

OBJECTIVE

HIV pre-exposure prophylaxis (PrEP) use may lead to higher STI incidence via behavioural risk compensation. We examined changes in sexual behaviour between baseline and 6 months after PrEP initiation among MSM and transgender women (TGW).

DESIGN

Prospective, open-label demonstration study at a large sexually transmitted infection (STI) clinic in Amsterdam, the Netherlands.

METHODS

Participants answered questions about sexual behaviour in the preceding 3 months, including number of anal sex partners and frequency of anal sex with and without condom by partner type and were tested for STI. Sexual behaviour at baseline was compared with 6 months after PrEP initiation using Wilcoxon signed rank tests. Logistic regression was used to identify factors associated with an increase in receptive condomless anal sex acts (rCASa) with casual partners.

RESULTS

Data were available for 328 (99%) MSM and 2 (1%) TGW. The number of receptive and insertive condomless anal sex acts (CASa) increased (baseline: median 11, interquartile range 4-23; 6 months: median 14, interquartile range 6-26, P < 0.001), whereas the number of anal sex partners (P = 0.2) and anal sex acts (P = 0.8) remained unchanged. Prevalence of STI was stable. Older age, prior engagement in chemsex, recent use of postexposure prophylaxis and choosing a daily PrEP regimen at baseline were associated with an increase in rCASa with casual partners.

CONCLUSION

Over the first 6 months after initiation of PrEP, an increase in insertive and receptive CASa with casual partners was observed. Long-term follow-up data are needed and STI incidence needs to be closely monitored.

Reasons for nonadherence to the dapivirine vaginal ring: narrative explanations of objective drug-level results

OBJECTIVE(S)

MTN-020/ASPIRE trial and IPM-027/Ring Study recently proved the dapivirine vaginal ring was safe and effective with consistent use. To optimize the ring's impact, the barriers and facilitators to ring adherence must be understood and addressed.

METHODS

Former ASPIRE participants were stratified by age group (18-21; 22-45) and randomly selected at seven sites in Malawi, South Africa, Uganda and Zimbabwe, 12-17 months after trial exit. Using in-depth interviews or focus group discussions, ring use barriers were explored using structured guides and visual tools including individual-level depictions of dapivirine levels detected in plasma and returned rings.

RESULTS

A total of 187 were enrolled; 37% were 18-21 years when they began ASPIRE. Most (75%) had drug-level results, suggesting inconsistent ring use throughout ASPIRE. Participants viewed themselves as adherent, while simultaneously describing regular instances and reasons for ring removal (e.g. for sex or menses). Less adherent women reported fears that partners would oppose the ring or feel it during sex. High adherers expressed altruistic motivations for ring use. Women of all ages attributed young women's nonadherence to their tendency to be less 'serious' about the future, HIV prevention and the study; motivated predominantly by benefits; more fearful of fertility-related consequences; and to having less relationship control.

CONCLUSION

When presented with objective adherence data, participants provided reasons for intermittent ring use, while simultaneously portraying themselves as consistent ring users. Further research is needed to understand how women could use the ring in a way that fits into the context of their relationships and their lives while still conferring adequate HIV prophylaxis.

Exploring the Use of Pre-exposure Prophylaxis (PrEP) for HIV Prevention Among High-Risk People Who Use Drugs in Treatment

Introduction: Despite unequivocal evidence supporting the use of pre-exposure prophylaxis (PrEP), its scale-up has been gradual overall, and nearly absent among people who use drugs (PWUD). In the present study, we implemented the use of PrEP, as a part of an integrated HIV prevention approach, and explored the experiences and attitudes related to PrEP use among PWUD.

Methods: Between September 2016 and July 2017, we recruited 40 HIV-uninfected, methadone-maintained people, who reported HIV-risk behaviors, and were currently taking PrEP. We conducted both quantitative and in-depth semi-structured qualitative interviews that primarily focused on experiences, attitudes, acceptability, disclosure status, risk compensation-related attitudes, and barriers related to PrEP adherence.

Results: Results showed that participants were highly satisfied and perceived PrEP as valuable and acceptable for HIV prevention. Participants reported high adherence to PrEP. The most highly endorsed facilitators to PrEP adherence were use of memory aids, no out-of-pocket cost, perceived benefit, and support from social network. The barriers to adherence included side-effects, stigmatization, requirement of daily dosing, and accessibility of PrEP services. Additionally, participants expressed disagreement with the overall risk compensation-related attitudes (i.e., decreased personal concern about engaging in HIV risk behavior due to their perception that PrEP is now fully protecting them from contracting HIV) and indicated no increased engagement in risk behaviors while on PrEP.

Conclusions: The results from the current study provide preliminary evidence supporting the successful integration of PrEP within the substance abuse treatment setting, where high risk PWUD are concentrated.

HIV health care providers are ready to introduce pre-exposure prophylaxis in Central and Eastern Europe and neighbouring countries: data from the Euroguidelines in Central and Eastern Europe (ECEE) Network Group

OBJECTIVES

Pre-exposure prophylaxis (PrEP) for HIV infection has been introduced in only a few European countries. We investigated the potential to provide PrEP in the Central and Eastern European region, and in neighbouring countries.

METHODS

The Euroguidelines in Central and Eastern Europe (ECEE) Network Group was formed in February 2016 to review standards of care for HIV infection in the region. Information related to PrEP was collected through on-line surveys. Respondents were recruited by ECEE members based on their involvement in HIV care.

RESULTS

Seventy-six respondents from 23 countries participated in the survey. Twenty-six (34.2%) respondents reported that PrEP [tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC)] was registered by the drug registration authority in their country. Fifty-three (70.7%) respondents reported being aware of 'informal' PrEP use in their country. If they had access to PrEP, 56 (74.7%) would advise its use in their practice. Forty-five (59.2%) respondents had concerns regarding PrEP use, and 10 (13.3%) expressed the need for more training. Most of the respondents (88.2%) would provide PrEP to people with high-risk behaviours.

CONCLUSIONS

PrEP is already used informally in some countries in the region. Physicians are keen to use PrEP if and when it is accessible. Obstacles towards implementing PrEP in those countries were mostly related to lack of national guidelines, drug registration and governmental strategy.

Vaginal epidermal dendritic cells: defense against HIV-1 or a safe haven?

Langerhans cells (LCs) are likely among the first targets of HIV-1 infection due to their localization in mucosal tissues. In their recent work, Pena-Cruz and colleagues were able to study HIV-1 infection in vaginal epithelial DCs (VEDCs), termed CD1a+ VEDCs. They show that VEDCs are distinct from other blood- and tissue-derived DCs or LCs because they express the protein langerin but not the lectin receptor DC-SIGN, and they do not have Birbeck granules. The results from this study indicate that HIV-1 using CXCR4 replicates poorly in VEDCs but that a higher replication for HIV-1 using CCR5 strains is supported by VDECs. Furthermore, Pena-Cruz and colleagues demonstrate that VDECs can represent a viral reservoir in HIV-1-infected virologically suppressed women. As such, VDECs may represent another sanctuary of viral persistence and can be an additional obstacle to viral eradication.

Thirty Years of Research on Gay Men and HIV Prevention in France: A Narrative Review of the Literature

Research on homosexuality and HIV/AIDS in the social sciences has evolved into a vast and multiform field of study since the beginning of the epidemic in the Global North. Studies from France in this domain have remained relatively unknown at the international level. This article offers a narrative review of publications that resulted from research on homosexuality and HIV/AIDS, from 1985 to 2016. It offers an analysis of how the constitution of a field of research conditions the ways scientific questions are asked (and answered). This epistemological concern is addressed through a sociohistorical contextualization of the main issues surrounding prevention and how they have been addressed by researchers in France. A review of French publications on HIV prevention among gay men reveals certain specificities. In terms of the social science disciplines, psychology and psychoanalysis are much less present in this domain, whereas epidemiology, sociology, and anthropology are the most represented. The works analyzed in this article also reveal the circulation and local adaptations of risk categories imported from the English-speaking world, such as "relapse" and "bareback." Regardless, research on HIV prevention in France largely evolved contemporaneously in the same way that it did elsewhere.

Expert consensus statement on the science of HIV in the context of criminal law

INTRODUCTION

Globally, prosecutions for non-disclosure, exposure or transmission of HIV frequently relate to sexual activity, biting, or spitting. This includes instances in which no harm was intended, HIV transmission did not occur, and HIV transmission was extremely unlikely or not possible. This suggests prosecutions are not always guided by the best available scientific and medical evidence.

DISCUSSION

Twenty scientists from regions across the world developed this Expert Consensus Statement to address the use of HIV science by the criminal justice system. A detailed analysis of the best available scientific and medical research data on HIV transmission, treatment effectiveness and forensic phylogenetic evidence was performed and described so it may be better understood in criminal law contexts. Description of the possibility of HIV transmission was limited to acts most often at issue in criminal cases. The possibility of HIV transmission during a single, specific act was positioned along a continuum of risk, noting that the possibility of HIV transmission varies according to a range of intersecting factors including viral load, condom use, and other risk reduction practices. Current evidence suggests the possibility of HIV transmission during a single episode of sex, biting or spitting ranges from no possibility to low possibility. Further research considered the positive health impact of modern antiretroviral therapies that have improved the life expectancy of most people living with HIV to a point similar to their HIV-negative counterparts, transforming HIV infection into a chronic, manageable health condition. Lastly, consideration of the use of scientific evidence in court found that phylogenetic analysis alone cannot prove beyond reasonable doubt that one person infected another although it can be used to exonerate a defendant.

CONCLUSIONS

The application of up-to-date scientific evidence in criminal cases has the potential to limit unjust prosecutions and convictions. The authors recommend that caution be exercised when considering prosecution, and encourage governments and those working in legal and judicial systems to pay close attention to the significant advances in HIV science that have occurred over the last three decades to ensure current scientific knowledge informs application of the law in cases related to HIV.

Management of acute HCV infection in the era of direct-acting antiviral therapy

The management of acute HCV infection has not been standardized following the availability of direct-acting antiviral agents (DAAs) for chronic HCV infection, and substantial uncertainty exists regarding the optimal treatment regimen and duration. Despite the lack of direct evidence, the 2016 American Association for the Study of Liver Diseases (AASLD)-Infectious Diseases Society of America (IDSA) guidelines supported "the same regimens for acute HCV as recommended for chronic HCV infection … owing to high efficacy and safety", whereas the 2016 European Association for the Study of the Liver (EASL) guidelines recommended sofosbuvir-ledipasvir, sofosbuvir-velpatasvir or sofosbuvir plus daclatasvir for 8 weeks in acute HCV infection, with a longer duration of 12 weeks recommended for those infected with HIV and/or baseline HCV RNA levels >1,000,000 IU/ml. This Review outlines the epidemiology, natural history and diagnosis of acute HCV infection and provides contemporary information on DAAs for acute and recent HCV infection. The Review also discusses the 2016 AASLD-IDSA and EASL recommendations for acute HCV infection management in light of available evidence and highlights key differences in study populations and design that influence interpretation. We focus on populations at high risk of HCV transmission and acquisition, including people who inject drugs and HIV-positive men who have sex with men, and highlight the potential effects of diagnosis and treatment of acute HCV infection in contributing to HCV elimination.

How to do it: setting up a PrEP service in an integrated sexual reproductive health service setting

Pre-exposure prophylaxis for HIV (PrEP) has been shown to reduce transmission of HIV in a number of trials; however, there is limited evidence regarding the optimal way to deliver PrEP through pre-existing UK services, particularly through fully integrated drop-in sexual health service models. PrEP in the form of Truvada was launched in Wales in July 2017. We set up a PrEP service to be delivered via our drop-in integrated sexual reproductive health service. In the first 5 months of PrEP service provision, we found unforeseen levels of comorbidity, polypharmacy and renal impairment in our cohort of PrEP patients. As a result, we have altered our service model and all patients are now followed up in booked appointment PrEP clinics run by members of the HIV team. Those patients with estimated glomerular filtration rate (eGFR) of 60-70 mL/min or with eGFR of 60-80 mL/min and with comorbidities impacting on renal function are monitored every 4-6 weeks initially, and PrEP has been incorporated into our pre-existing virtual HIV renal clinic for discussion with a renal physician. The PrEP team clinicians report that monitoring and managing the PrEP cohort is now easier in its appointment-only format, although some patients have reported that they would prefer a drop-in system.

HIV pre-exposure prophylaxis (PrEP) in Spain: political and administrative situation

This study focuses on actions at the political and administrative level in Spain in relation to the implementation of pre-exposure prophylaxis (PrEP). We analysed a whole range of different formal initiatives taken by the political and administrative actors involved. The information was obtained from official public data sources. As of February 2018, PrEP had not been implemented. The decision is dependent on both state and regional governments. The Ministry of Health and some Autonomous Regions are working on different interventions, but without providing an implementation timetable. The political parties have kept a very low profile in terms of initiatives related to the implementation of PrEP. From a legal point of view, proceedings are passing back and forth with the extension of the patent. The role of intergovernmental and interdepartmental institutions is very important for the implementation of PrEP in Spain.

Risk of HIV transmission during combined ART initiation for HIV-infected persons with severe immunosuppression

Background

Individuals presenting for care with severe immunosuppression typically have high plasma HIV viral load (pVL) and may transmit HIV before and after initiation of combination antiretroviral therapies (cART).

Patients and methods

Using risk equations and data collected in the IMEA 040 DATA trial on sexual behaviour and pVL level of 84 HIV-infected patients (23 women), we estimated monthly rates of HIV transmission for each virologically unsuppressed participant (pVL >50 copies/mL) who reported sex with HIV-negative or unknown serostatus (HNUS) partners at cART initiation, 24 weeks (W24) and W48 after; rates were considered negligible for other participants.

Results

At cART initiation, median pVL was 5.4 log10 copies/mL. The percentage of virologically unsuppressed patients decreased, from 100% at cART initiation to 27% (95% CI 16%-43%) for heterosexuals and 8% (95% CI 2%-22%) for MSM at W48 (P < 0.001). The percentage of patients reporting sex with HNUS partners increased between cART initiation and W48, from 23% (95% CI 10%-42%) to 42% (95% CI 25%-61%) for heterosexuals (P = 0.042) and from 41% (95% CI 21%-64%) to 73% (95% CI 52%-88%) for MSM (P = 0.004). Median monthly HIV transmission rates were 0.0540 (IQR 0.0339-0.0742) for MSM and 0.0018 (IQR 0.0014-0.0191) for heterosexuals at cART initiation, and were reduced by 95% (95% CI 87%-100%) for heterosexuals and 98% (95% CI 95%-100%) for MSM as early as W24.

Conclusions

Risk of onward transmission for severely immunosuppressed individuals is high before and within the first weeks of cART, and persists, at a substantially reduced level, beyond 24 weeks of cART for some individuals. Earlier cART and protecting HIV-negative partners until full viral suppression is achieved could reduce HIV transmission.

Tackling HIV and AIDS: contributions by non-human primate models

During the past three decades, non-human primate (NHP) models have gained an increasing importance in HIV basic and translational research. In contrast to natural host models, infection of macaques with virulent simian or simian-human immunodeficiency viruses (SIV, SHIV) results in a disease that closely resembles HIV infection and AIDS. Although there is no perfect animal model, and each of the available models has its benefits and limitations, carefully designed NHP studies with selection of experimental variables have unraveled important questions of basic pathogenesis and have provided the tools to explore and screen intervention strategies. For example, NHP studies have advanced our understanding of the crucial events during early infection, and have provided proof-of-concept of antiretroviral drug treatment and prevention strategies such as pre-exposure prophylaxis (PrEP) regimes that are increasingly used worldwide, and upon overcoming further barriers of implementation, have the potential to make the next generation AIDS-free. Remaining goals include the pursuit of an effective HIV vaccine, and HIV cure strategies that would allow HIV-infected people to ultimately stop taking antiretroviral drugs. Through a reiterative process with feed-back from results of human studies, NHP models can be further validated and strengthened to advance our scientific knowledge and guide clinical trials.

The averted infections ratio: a novel measure of effectiveness of experimental HIV pre-exposure prophylaxis agents

Tenofovir disoproxil fumarate combined with emtricitabine is a highly effective oral pre-exposure prophylaxis (PrEP) agent for preventing the acquisition of HIV. This effectiveness has consequences for the design and analysis of trials assessing experimental PrEP regimens, which now generally include an active-control tenofovir disoproxil fumarate plus emtricitabine group, rather than a placebo group, as a comparator. Herein, we describe major problems in the interpretation of the primary measure of effectiveness proposed for these trials, namely the ratio of HIV incidence in the experimental agent group to that in the active-control group. We argue that valid interpretation requires an assumption about one of two parameters: either the incidence among trial participants had they not received PrEP or the effectiveness of tenofovir disoproxil fumarate plus emtricitabine within the trial. However, neither parameter is directly observed because of the absence of a no-treatment group, thus requiring the use of external evidence or subjective judgment. We propose an alternative measure of effectiveness based on the concept of averted infections, which incorporates one of these parameters. The measure is simple to interpret, has clinical and public health relevance, and is a natural preservation-of-effect criterion for assessing statistical non-inferiority. Its adoption could also allow the use of smaller sample sizes, currently a major barrier to the assessment of experimental PrEP regimens.

Hybrid stochastic framework predicts efficacy of prophylaxis against HIV: An example with different dolutegravir prophylaxis schemes

To achieve the 90-90-90 goals set by UNAIDS, the number of new HIV infections needs to decrease to approximately 500,000 by 2020. One of the 'five pillars' to achieve this goal is pre-exposure prophylaxis (PrEP). Truvada (emtricitabine-tenofovir) is currently the only medication approved for PrEP. Despite its advantages, Truvada is costly and requires individuals to adhere to the once-daily regimen. To improve PrEP, many next-generation regimen, including long-acting formulations, are currently investigated. However, pre-clinical testing may not guide candidate selection, since it often fails to translate into clinical efficacy. On the other hand, quantifying prophylactic efficacy in the clinic is ethically problematic and requires to conduct long (years) and large (N>1000 individuals) trials, precluding systematic evaluation of candidates and deployment strategies. To prioritize- and help design PrEP regimen, tools are urgently needed that integrate pharmacological-, viral- and host factors determining prophylactic efficacy. Integrating the aforementioned factors, we developed an efficient and exact stochastic simulation approach to predict prophylactic efficacy, as an example for dolutegravir (DTG). Combining the population pharmacokinetics of DTG with the stochastic framework, we predicted that plasma concentrations of 145.18 and 722.23nM prevent 50- and 90% sexual transmissions respectively. We then predicted the reduction in HIV infection when DTG was used in PrEP, PrEP 'on demand' and post-exposure prophylaxis (PEP) before/after virus exposure. Once daily PrEP with 50mg oral DTG prevented 99-100% infections, and 85% of infections when 50% of dosing events were missed. PrEP 'on demand' prevented 79-84% infections and PEP >80% when initiated within 6 hours after virus exposure and continued for as long as possible. While the simulation framework can easily be adapted to other PrEP candidates, our simulations indicated that oral 50mg DTG is non-inferior to Truvada. Moreover, the predicted 90% preventive concentrations can guide release kinetics of currently developed DTG nano-formulations.

HIV prevention strategies and risk of infection: a model-based analysis

Risk populations for HIV infections tend to neglect condom use, making alternative preventive approaches necessary. Accordingly, we modelled the risk of sexual HIV transmission for condom use vs. use of rapid diagnostic test (RDT) systems with subsequent exclusion of potential sexual partners with a correctly or falsely positive test from unprotected sex with and without the use of HIV pre-exposure prophylaxis (PrEP) in a bio-statistical approach. We combined a previously described model of transmission risk for HIV-exposed individuals with a newly suggested model of risk of HIV exposure for sexually active HIV-negative individuals. The model was adapted for several stages of infection and different strategies of HIV infection prevention.HIV prevention with RDTs can reduce the transmission risk by up to 97% compared with having sex without any prevention and up to 80% compared with condom use. Nevertheless, RDT-based prevention strategies demonstrate a lack of protection in several stages of infection; in particular, RNA-based RDT systems may fail under treatment. RDT-based pre-screening of potential sex partners prior to unprotected sexual contacts substantially reduces HIV transmission risk. Combination of different prevention strategies is advisable for high-risk groups.

The ANRS-Ipergay trial, an opportunity to use qualitative research to understand the perception of the "participant"-physician relationship

The ANRS-IPERGAY trial consisted in providing sexual activity-based antiretroviral prophylaxis for HIV prevention (PrEP) with a package of prevention tools (counselling, condoms, HIV and sexually transmitted infections' screening) to highly exposed HIV-negative men who have sex with men (MSM). Few data exist concerning the patient-physician relationship in the particular context of PrEP, where physicians discuss sexual behaviours with MSM who are not classic patients, in that consultation is for prevention purposes, not for illness. This study took place during the open-label extension of ANRS-IPERGAY trial when all participants received PrEP. In this qualitative study, we examined how physicians perceived their relationship with participants in the ANRS-IPERGAY trial. Of all 30 physicians involved in the trial who were contacted by email to participate in an interview about their opinions and perceptions of ANRS-IPERGAY 18 volunteered to participate in the current sub-study. We performed a vertical analysis for each interview to identify the extract in each physician's discourse concerning their relationship with MSM participants, and conducted a horizontal analysis to construct the thematic tree and subsequently investigate differences and similitudes between themes. An analysis of all physicians' discourses showed that the participant-physician relationship during the trial could be described through 4 themes: (i) personal experience of the relationship, (ii) trust and non-judgement, (iii) positive relational climate and (iv) influence of physician's characteristics (age, gender, etc.) on relationship. We found that the particular context of PrEP led some physicians to adopt a patient-as-partner approach during consultations rather than a paternalist or hierarchical approach. Indeed, the close follow-up provided by the trial and the active role of patients in their own prevention care trajectory, are more compatible with the patient-as-partner approach. The prescription of PrEP may lead to an evolution in patient-physician relationships and may even modify the professional identity of physicians.

Lessons learned from the experiences of informal PrEP users in France: results from the ANRS-PrEPage study

Before January 2016, Pre-Exposure Prophylaxis (PrEP), a new biomedical HIV-prevention tool, was only available in France via ANRS-Ipergay clinical study but informal use was reported outside this setting. PrEPage qualitative study reports profiles and experiences of participants who used PrEP outside of a biomedical trial before this prevention method was authorized. Between March 2015 and February 2016, a cross-section of twenty-four informal PrEP users, mostly MSM, was recruited to complete in-depth semi-structured interviews. While ANRS-Ipergay was still ongoing (2012-2016), participants described their initiation to PrEP, the way they used it and the difficulties they faced to acquire antiretroviral drugs in an environment where PrEP was still not widely known and often criticized . Through the testimonies, different user profiles and motivation toward informal PrEP use emerged: (a) participants who have increasing difficulties using condoms, (b) "opportunists" who tried PrEP without the intention of using it regularly and (c) participants with a risk aversion who sought additional protection against HIV. Participants chose to use PrEP and/or their usual prevention strategies depending on available supplies, type of partners and individual attitudes toward risk. The feeling of living a safer sex life helped participants to outweigh the fear of possible toxicity and drug resistance. Participants' needs and expectations about PrEP implementation in France were also presented.

Protocol for an HIV Pre-exposure Prophylaxis (PrEP) Population Level Intervention Study in Victoria Australia: The PrEPX Study

Background: Pre-exposure prophylaxis (PrEP) is the use of HIV anti-retroviral therapy to prevent HIV transmission in people at high risk of HIV acquisition. PrEP is highly efficacious when taken either daily, or in an on-demand schedule. In Australia co-formulated tenofovir-emtricitabine is registered for daily use for PrEP, however, this co-formulation is not listed yet on the national subsidized medicines list. We describe a study protocol that aims to demonstrate if the provision of PrEP to up to 3800 individuals at risk of HIV in Victoria, Australia reduces HIV incidence locally by 25% generally and 30% among GBM.

Methods: PrEPX is a population level intervention study in Victoria, Australia in which generic PrEP will be delivered to 3800 individuals for up to 36 months. Study eligibility is consistent with the recently updated 2017 Australian PrEP guidelines. Participants will attend study clinics, shared care clinics, or outreach clinics for quarterly HIV/STI screening, biannual renal function tests and other clinical care as required. Study visits and STI diagnoses will be recorded electronically through the ACCESS surveillance system. At each study visit participants will be invited to complete behavioral surveys that collect demographics and sexual risk data. Diagnosis and behavioral data will be compared between PrEPX participants and other individuals testing within the ACCESS surveillance system. A subset of participants will complete in depth surveys and interviews to collect attitudes, beliefs and acceptability data. Participating clinics will provide clinic level data on implementation and management of PrEPX participants. The population level impact on HIV incidence will be assessed using Victorian HIV notification data.

Discussion: This study will collect evidence on the real world impact of delivery of PrEP to 3800 individuals at risk of acquiring HIV in Victoria. This study will provide important information for the broader implementation of PrEP planning upon listing of the tenofovir-emtricitabine on the national subsidized list of medicines. The study is registered on the Australian New Zealand Clinical Trials Registry (ACTRN12616001215415)

US Black Women and Human Immunodeficiency Virus Prevention: Time for New Approaches to Clinical Trials

Black women bear the highest burden of human immunodeficiency virus (HIV) infection among US women. Tenofovir/emtricitabine HIV prevention trials among women in Africa have yielded varying results. Ideally, a randomized controlled trial (RCT) among US women would provide data for guidelines for US women's HIV preexposure prophylaxis use. However, even among US black women at high risk for HIV infection, sample size requirements for an RCT with HIV incidence as its outcome are prohibitively high. We propose to circumvent this large sample size requirement by evaluating relationships between HIV incidence and drug concentrations measured among participants in traditional phase 3 trials in high-incidence settings and then applying these observations to drug concentrations measured among at-risk individuals in lower-incidence settings, such as US black women. This strategy could strengthen the evidence base to enable black women to fully benefit from prevention research advances and decrease racial disparities in HIV rates.

Doxycycline Prophylaxis for Bacterial Sexually Transmitted Infections: Promises and Perils

Despite their high global incidence, sexually transmitted infections (STIs) remain a neglected area of research. Increased rates of STIs have been reported in particular among men who have sex with men (MSM) probably because of the advances in the treatment and prophylaxis of human immunodeficiency virus (HIV) infection with a decrease in condom use. A recent report among MSM showed that the use of postexposure prophylaxis with doxycycline could dramatically reduce the incidence of chlamydia and syphilis but not of gonorrhea. The long-term consequences of this strategy are yet unknown, especially the risk of selection and dissemination of syphilis and chlamydia strains with doxycycline resistance, which has not been reported yet.

HIV Prevention After Discontinuing Pre-Exposure Prophylaxis: Conclusions From a Case Study

Pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate in combination with emtricitabine (FTC) is a highly effective form of HIV prevention. Endeavors of health-care providers and activists in many countries over the world are directed at making access to PrEP possible, or increasing PrEP use among men-who-have-sex-with-men (MSM). We argue while this effort is necessary, we also need to consider modes of HIV prevention after a period of PrEP use. PrEP uptake is not a one-way street, meaning that individuals may discontinue PrEP use, either voluntarily and involuntarily. Voluntary discontinued PrEP use in conjunction with decreased or no HIV risk exposure is unproblematic, but involuntary discontinuations with continuous high level of HIV risk exposure calls for tailored post-PrEP use HIV prevention. We present a case study of an MSM individual who discontinued PrEP for medical reasons (renal function) and seroconverted soon afterward, to illustrate the need for tailored HIV prevention post-PrEP. Furthermore, we provide additional contexts of PrEP discontinuation leading to populations that are in need for post-PrEP types of HIV prevention. Subsequently, we present suggestions for modes of post-PrEP HIV prevention based on knowledge–communication–choice model. Community organization and health-care providers should consider and prepare their HIV prevention consulting protocols for such types of clients and add post-PrEP HIV prevention measures to their consulting offer.

Randomized Controlled Trial of Daily Text Messages to Support Adherence to Preexposure Prophylaxis in Individuals at Risk for Human Immunodeficiency Virus: The TAPIR Study

Background

Adherence is critical for efficacy of tenofovir disoproxil fumarate/emtricitabine (FTC) as preexposure prophylaxis (PrEP).

Methods

Between February 2013 and February 2016, 398 men who have sex with men and transgender women were randomized 1:1 to receive individualized texting for adherence building (iTAB) or standard care (SoC) for 48 weeks. The primary endpoint was dried blood spot (DBS) tenofovir diphosphate (TFV-DP) concentrations at both week 12 and the last on-drug visit of >719 fmol/punch (ie, adequate adherence). Secondary outcomes included DBS TFV-DP concentrations of >1246 fmol/punch (ie, near-perfect adherence) and plasma FTC >350 ng/mL (consistent with dosing within the past 24 hours).

Results

Concentrations >719 fmol/punch of TFV-DP were found in 88.6% of participants at week 12 and 82.5% at week 48. For the primary endpoint, the study arms did not differ (72.0% in iTAB and 69.2% in SoC; P > .05). For the secondary composite endpoint of >1246 fmol/punch the iTAB arm was superior to SoC (33.5% vs 24.8%; P = .06), reaching statistical significance when adjusting for age (odds ratio, 1.56 [95% confidence interval, 1.00-2.42]; P < .05). At week 48, iTAB was superior to SoC for near-perfect adherence (51.0% vs 37.4%; P = .02). At week 12, iTAB was superior to SoC for dosing in past 24 hours by plasma FTC (47.5% vs 33.3%; P = .007), but not at weeks 24, 36, and 48 (all P > .05).

Conclusions

Automated text messaging is a low-burden tool that improves durability of near-perfect PrEP adherence.

Clinical Trials Registration

NCT01761643.