Predictors of Long-Term HIV Pre-exposure Prophylaxis Adherence After Study Participation in Men Who Have Sex With Men

Improving Delivery and Use of HIV Pre-Exposure Prophylaxis in the US: A Systematic Review of Implementation Strategies and Adjunctive Interventions

Implementation of pre-exposure prophylaxis (PrEP) to prevent HIV transmission is suboptimal in the United States. To date, the literature has focused on identifying determinants of PrEP use, with a lesser focus on developing and testing change methods to improve PrEP implementation. Moreover, the change methods available for improving the uptake and sustained use of PrEP have not been systematically categorized. To summarize the state of the literature, we conducted a systematic review of the implementation strategies used to improve PrEP implementation among delivery systems and providers, as well as the adjunctive interventions used to improve the uptake and persistent adherence to PrEP among patients. Between November 2020 and January 2021, we searched Ovid MEDLINE, PsycINFO, and Web of Science for peer reviewed articles. We identified 44 change methods (18 implementation strategies and 26 adjunctive interventions) across a variety of clinical and community-based service settings. We coded implementation strategies and adjunctive interventions in accordance with established taxonomies and reporting guidelines. Most studies focused on improving patient adherence to PrEP and most conducted pilot trials. Just over one-third of included studies demonstrated a positive effect on outcomes. In order to end the human immunodeficiency virus (HIV) epidemic in the U.S., future, large scale HIV prevention research is needed that develops and evaluates implementation strategies and adjunctive interventions for target populations disproportionately affected by HIV.

HIV Prevention Among Men Who Have Sex With Men: Tenofovir Alafenamide Combination Preexposure Prophylaxis Versus Placebo

BACKGROUND

While noninferiority of tenofovir alafenamide and emtricitabine (TAF/FTC) as preexposure prophylaxis (PrEP) for the prevention of human immunodeficiency virus (HIV) has been shown, interest remains in its efficacy relative to placebo. We estimate the efficacy of TAF/FTC PrEP versus placebo for the prevention of HIV infection.

METHODS

We used data from the DISCOVER and iPrEx trials to compare TAF/FTC to placebo. DISCOVER was a noninferiority trial conducted from 2016 to 2017. iPrEx was a placebo-controlled trial conducted from 2007 to 2009. Inverse probability weights were used to standardize the iPrEx participants to the distribution of demographics and risk factors in the DISCOVER trial. To check the comparison, we evaluated whether risk of HIV infection in the shared tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) arms was similar.

RESULTS

Notable differences in demographics and risk factors occurred between trials. After standardization, the difference in risk of HIV infection between the TDF/FTC arms was near zero. The risk of HIV with TAF/FTC was 5.8 percentage points lower (95% confidence interval [CI], -2.0% to -9.6%) or 12.5-fold lower (95% CI, .02 to .31) than placebo standardized to the DISCOVER population.

CONCLUSIONS

There was a reduction in HIV infection with TAF/FTC versus placebo across 96 weeks of follow-up.

CLINICAL TRIALS REGISTRATION

NCT02842086 and NCT00458393.

Early disengagement from HIV pre-exposure prophylaxis services and associated factors among female sex workers in Dar es Salaam, Tanzania: a socioecological approach

INTRODUCTION

Pre-exposure prophylaxis (PrEP) is an effective HIV prevention tool when taken as prescribed. However, suboptimal use may challenge its real-life impact. To support female sex workers in their efforts to prevent themselves from HIV, it is essential to identify factors that contribute to early disengagement from PrEP care. In this study, we aimed to estimate the risk of early disengagement from PrEP services among female sex workers in Tanzania and associated factors using a socioecological model as a guiding framework.

METHODS

The study was conducted as part of a pragmatic mHealth trial for PrEP roll-out in Dar es Salaam in 2021. We estimated the risk of early disengagement, defined as not presenting for the first follow-up visit (within 56 days of enrolment), and its associations with individual, social, behavioural and structural factors (age, self-perceived HIV risk, mental distress, harmful alcohol use, condom use, number of sex work clients, female sex worker stigma and mobility) using multivariable logistic regression models, with marginal standardisation to obtain adjusted relative risks (aRR).

RESULTS

Of the 470 female sex workers enrolled in the study, 340 (74.6%) did not attend the first follow-up visit (disengaged). Mental distress (aRR=1.14; 95% CI 1.01 to 1.27) was associated with increased risk of disengagement. Participants who reported a higher number of clients per month (10-29 partners: aRR=0.87; 95% CI 0.76 to 0.98 and ≥30 partners: aRR=0.80; 95% CI 0.68 to 0.91) and older participants (≥35 years) (RR=0.75; 95% CI 0.56 to 0.95) had a lower risk of disengagement.

CONCLUSIONS AND RECOMMENDATIONS

Early disengagement with the PrEP programme was high. Mental distress, younger age and having fewer clients were risk factors for disengagement. We argue that PrEP programmes could benefit from including mental health screening and treatment, as well as directing attention to younger sex workers and those reporting fewer clients.

Substance Use and Adherence to HIV Pre-Exposure Prophylaxis in Studies Enrolling Men Who Have Sex with Men and Transgender Women: A Systematic Review

Optimal adherence to pre-exposure prophylaxis (PrEP) is critical, but challenging. Men who have sex with men and transgender women have high rates of HIV incidence and substance use. Substance use is associated with reduced adherence to other medications, but associations between substance use and adherence to PrEP are less clear. Thus, the current review 1) systematically evaluates the measurement of substance use and PrEP adherence in studies examining both and 2) summarizes reported findings. Peer-reviewed articles published between 2010 - April 2021 examining associations between substance use and PrEP adherence were reviewed. Fifty studies met inclusion criteria. Assessment of substance use (i.e., mostly via self-reports at baseline) and PrEP adherence (i.e., often via tenofovir diphosphate [TFV-DP] concentration levels at follow-up) varied considerably across studies. Many studies used categorical variables (e.g., substance use: yes/no). Studies using TFV-DP levels defined adherence consistently (i.e., TFV-DP ≥ 700 fmol/punch), with slight variations. Qualitative studies (n = 10) indicated that substance use (mainly alcohol) is related to poorer PrEP adherence. While quantitative findings to date are equivocal for alcohol, there is a pattern of findings linking stimulant use with poorer PrEP adherence. This review reveals four methodological gaps, which can be addressed in future research by: 1) use of uniform benchmarks for substance use measures, 2) prospective assessment for substance use, 3) use of continuous outcome variables wherever possible, and 4) more extensive consideration of potential confounders. Addressing these methodological gaps may help us reach more definitive conclusions regarding associations between substance use and PrEP adherence.

Intention to use PrEP among men who have sex with men and engage in chemsex: an international descriptive study

Background

Pre-exposure prophylaxis (PrEP) is a valuable tool in the response to the HIV epidemic, recommended for groups with a higher risk of HIV infection, such as men who have sex with men (MSM), particularly in the context of high-risk sexual behavior such as chemsex.

Purpose

This study aimed to analyze the prevalence and factors associated with the intention to use PrEP among MSM who engage in chemsex in Brazil and Portugal.

Methods

This was a cross-sectional study of a secondary dataset from a larger study conducted between January 2020 and May 2021 throughout Brazil and Portugal involving 1852 MSM who engage in chemsex. An initial descriptive analysis was performed to calculate the absolute and relative frequencies of independent variables related to the intention to use PrEP among MSM. A multivariate regression model was developed to identify factors independently associated with the intention to use PrEP.

Results

Although a high level of PrEP knowledge (85.75%) was observed among MSM who engage in chemsex, the prevalence of intention to use PrEP was only 59.07%. Five variables were associated with a higher prevalence of intention to use PrEP [engaging in double penetration - adjusted prevalence ratio (aPR): 1.56, 95% CI: 1.44-1.69; being assigned female sex at birth - aPR: 1.34, 95% CI: 1.12-1.61; cruising - aPR: 1.21, 95% CI: 1.06-1.38; not using condoms - aPR: 1.20, 95% CI: 1.05-1.36; and being an immigrant - aPR: 1.16; 95% CI: 1.07-1.25], while having knowledge of postexposure prophylaxis (aPR: 0.91; 95% CI: 0.84-0.98), having a casual sexual partner (aPR: 0.86 and 0.85; 95% CI: 0.74-0.99 and 0.74-0.98), and engaging in group sex (aPR: 0.81; 95% CI: 0.73-0.90) were associated with a lower intention to use PrEP.

Conclusion

The intention to use PrEP among MSM who engage in chemsex was high, and several factors were associated with this intention. Understanding the factors associated with the intention to use PrEP among MSM practicing chemsex is crucial for developing targeted interventions to increase PrEP uptake in this population. The results of this study suggest that tailored approaches are necessary to promote PrEP use in this population.

Determinants of Pre-exposure Prophylaxis (PrEP) Implementation in Transgender Populations: A Qualitative Scoping Review

We conducted a scoping review of contextual factors impeding uptake and adherence to pre-exposure prophylaxis in transgender communities as an in-depth analysis of the transgender population within a previously published systematic review. Using a machine learning screening process, title and abstract screening, and full-text review, the initial systematic review identified 353 articles for analysis. These articles were peer-reviewed, implementation-related studies of PrEP in the U.S. published after 2000. Twenty-two articles were identified in this search as transgender related. An additional eleven articles were identified through citations of these twenty-two articles, resulting in thirty-three articles in the current analysis. These thirty-three articles were qualitatively coded in NVivo using adapted constructs from the Consolidated Framework for Implementation Research as individual codes. Codes were thematically assessed. We point to barriers of implementing PrEP, including lack of intentional dissemination efforts and patience assistance, structural factors, including sex work, racism, and access to gender affirming health care, and lack of provider training. Finally, over 60% of articles lumped cisgender men who have sex with men with trans women. Such articles included sub-samples of transgender individuals that were not representative. We point to areas of growth for the field in this regard.

Barriers and Facilitators to HIV Pre-Exposure Prophylaxis Uptake Among Men Who have Sex with Men Who Use Stimulants: A Qualitative Study

The HIV epidemic disproportionately impacts men who have sex with men (MSM), particularly those who use stimulants. We explored barriers and facilitators to pre-exposure prophylaxis (PrEP) uptake among this population. From June 2018 through February 2019, we conducted semi-structured interviews in Providence, Rhode Island, and New Haven, Connecticut, with 21 MSM who reported recent (past six months) stimulant use. We identified individual, interpersonal, and structural barriers to PrEP, including: (1) high awareness but mixed knowledge of PrEP, resulting in concerns about side effects and drug interactions; (2) interest that was partly determined by substance use and perceived HIV risk; (3) fragmented and constrained social networks not conducive to disseminating PrEP information; and (4) PrEP access, such as insurance coverage and cost. Our findings suggest potential approaches to increase PrEP uptake in this group, including promotion through mainstream and social media, clarifying misinformation, and facilitating increased access through structural interventions.

Evidence and implication of interventions across various socioecological levels to address pre-exposure prophylaxis uptake and adherence among men who have sex with men in the United States: a systematic review

BACKGROUND

Pre-exposure prophylaxis (PrEP) represents a proven biomedical strategy to prevent HIV transmissions among men who have sex with men (MSM) in the United States (US). Despite the design and implementation of various PrEP-focus interventions in the US, aggregated evidence for enhancing PrEP uptake and adherence is lacking. The objective of this systematic review is to synthesize and evaluate interventions aimed to improve PrEP uptake and adherence among MSM in the US, and identify gaps with opportunities to inform the design and implementation of future PrEP interventions for these priority populations.

METHODS

We followed the PRISMA guidelines and conducted a systematic review of articles (published by November 28, 2021) with a focus on PrEP-related interventions by searching multiple databases (PubMed, MEDLINE, Web of Science and PsycINFO). Details of PrEP interventions were characterized based on their socioecological level(s), implementation modalities, and stage(s) of PrEP cascade continuum.

RESULTS

Among the 1363 articles retrieved from multiple databases, 42 interventions identified from 47 publications met the inclusion criteria for this review. Most individual-level interventions were delivered via text messages and/or apps and incorporated personalized elements to tailor the intervention content on participants' demographic characteristics or HIV risk behaviors. Interpersonal-level interventions often employed peer mentors or social network strategies to enhance PrEP adoption among MSM of minority race. However, few interventions were implemented at the community-, healthcare/institution- or multiple levels.

CONCLUSIONS

Interventions that incorporate multiple socioecological levels hold promise to facilitate PrEP adoption and adherence among MSM in the US given their acceptability, feasibility, efficacy and effectiveness. Future PrEP interventions that simultaneously address PrEP-related barriers/facilitators across multiple socioecological levels should be enhanced with a focus to tackle contextual and structural barriers (e.g., social determinants of health, stigma or medical mistrust) at the community- and healthcare/institution-level to effectively promote PrEP use for MSM of color.

Running with Scissors: a Systematic Review of Substance Use and the Pre-exposure Prophylaxis Care Continuum Among Sexual Minority Men

Purpose of Review

Patterns of sexualized drug use, including stimulants (e.g., methamphetamine) and chemsex drugs, are key drivers of HIV incidence among sexual minority men (SMM). Although pre-exposure prophylaxis (PrEP) mitigates HIV risk, there is no consensus regarding the associations of substance use with the PrEP care continuum.

Recent Findings

SMM who use substances are as likely or more likely to use PrEP. Although SMM who use stimulants experience greater difficulties with daily oral PrEP adherence, some evidence shows that SMM who use stimulants or chemsex drugs may achieve better adherence in the context of recent condomless anal sex. Finally, SMM who use substances may experience greater difficulties with PrEP persistence (including retention in PrEP care).

Summary

SMM who use stimulants and other substances would benefit from more comprehensive efforts to support PrEP re-uptake, adherence, and persistence, including delivering behavioral interventions, considering event-based dosing, and providing injectable PrEP.

Factors associated with self-reported adherence to daily oral pre-exposure prophylaxis among men who have sex with man and transgender women: PrEP Brasil study

Understanding the factors associated with pre-exposure prophylaxis (PrEP) adherence may help in the development of strategies to support, motivate and sustain PrEP use. This study estimated self-reported adherence, described perceived barriers and facilitators and investigated factors associated with adherence to daily oral PrEP among men who have sex with man (MSM) and transgender women after 1 year of PrEP use in Brazil. PrEP Brasil was a prospective, multicentre, open-label demonstration study with MSM and transgender women at high risk for HIV infection. We used logistic regression to evaluate factors associated with complete adherence (not forgetting to take any pills in the past 30 days) at week 48. Of 338 participants included in this analysis, 60% reported complete adherence to daily oral PrEP at week 48. Perceived barriers and facilitators to daily oral PrEP were reported by 38.2% and 98.5%, respectively. The most reported barrier and facilitator were 'I forgot to take my pills' (19.2%) and 'Associate PrEP with a daily activity/task' (58.6%), respectively. In final multivariable analysis, living in Rio de Janeiro (aOR: 0.38; 95% CI: 0.20-0.73), being transgender women (aOR: 0.22; 95% CI: 0.07-0.73), reporting stimulant use (a OR: 0.40; 95% CI: 0.20-0.80) and having any perceived barriers to daily oral PrEP (aOR: 0.12; 95% CI: 0.07-0.23) were associated with decreased odds of complete adherence. Our findings provide information for developing the best practices to promote PrEP adherence in the Brazilian context.

Grindr Users Take More Risks, but Are More Open to Human Immunodeficiency Virus (HIV) Pre-exposure Prophylaxis: Could This Dating App Provide a Platform for HIV Prevention Outreach?

BACKGROUND

Technology has changed the way that men who have sex with men (MSM) seek sex. More than 60% of MSM in the United States use the internet and/or smartphone-based geospatial networking apps to find sex partners. We correlated use of the most popular app (Grindr) with sexual risk and prevention behavior among MSM.

METHODS

A nested cohort study was conducted between September 2018 and June 2019 among MSM receiving community-based human immunodeficiency virus (HIV) and sexually transmitted infection (STI) screening in central San Diego. During the testing encounter, participants were surveyed for demographics, substance use, risk behavior (previous 3 months), HIV pre-exposure prophylaxis (PrEP) use, and Grindr usage. Participants who tested negative for HIV and who were not on PrEP were offered immediate PrEP.

RESULTS

The study included 1256 MSM, 1090 of whom (86.8%) were not taking PrEP. Overall, 580 of 1256 (46%) participants indicated that they used Grindr in the previous 7 days. Grindr users reported significantly higher risk behavior (greater number of male partners and condomless sex) and were more likely to test positive for chlamydia or gonorrhea (8.6% vs 4.7% of nonusers; P = .005). Grindr users were also more likely to be on PrEP (18.7% vs 8.7% of nonusers; P < .001) and had fewer newly diagnosed HIV infections (9 vs 26 among nonusers; P = .014). Grindr users were also nearly twice as likely as nonusers to initiate PrEP (24.6% vs 14%; P < .001).

CONCLUSIONS

Given the higher risk behavior and greater acceptance of PrEP among MSM who used Grindr, Grindr may provide a useful platform to promote HIV and STI testing and increase PrEP uptake.

Chemsex is not a barrier to self-reported daily PrEP adherence among PROUD study participants

BACKGROUND

Pre-exposure prophylaxis (PrEP) is a novel HIV prevention method whereby HIV-negative individuals take the drugs tenofovir and emtricitabine to prevent HIV acquisition. Optimal adherence is critical for PrEP efficacy. Chemsex describes sexual activity under the influence of psychoactive drugs, in the UK typically; crystal methamphetamine, gamma-hydroxybutyrate(GHB) and/or mephedrone. Chemsex drug use has been associated with increased HIV transmission risk among gay, bisexual and other men who have sex with men (GBM) and poor ART adherence among people living with HIV. This study assessed whether self-reported chemsex events affected self-reported daily PrEP adherence among PROUD study participants.

METHODS

The PROUD study was an open-label, randomised controlled trial, conducted in thirteen English sexual health clinics, assessing effectiveness of TruvadaⓇ-PrEP among 544 HIV-negative GBM. The study reported an 86% risk-reduction of HIV from daily PrEP. Participants were asked about chemsex engagement at follow-up visits. Monthly self-reports of missed PrEP tablets were aggregated to assess adherence between visits. Univariable and multivariable regression analyses were performed to test for associations between chemsex and reporting less than seven out of seven intended doses(<7/7ID) in the 7 days before and/or after last condomless anal intercourse(CAI).

RESULTS

1479 follow-up visit forms and 2260 monthly adherence forms from 388 participants were included in the analyses, with 38.5% visit forms reporting chemsex since last visit and 29.9% follow-up periods reporting <7/7ID. No statistically significant associations were observed between reporting <7/7ID and chemsex (aOR=1.29 [95% CI 0.90-1.87], p = 0.168). Statistically significant associations were seen between reporting <7/7ID and participants perceiving that they would miss PrEP doses during the trial, Asian ethnicity, and reporting unemployment at baseline.

CONCLUSIONS

These analyses suggest PrEP remains a feasible and effective HIV prevention method for GBM engaging in chemsex, a practise which is prevalent in this group and has been associated with increased HIV transmission risk.

Universal HIV and Birth Cohort HCV Screening in San Diego Emergency Departments

Universal HIV and HCV screening in emergency departments (ED) can reach populations who are less likely to get tested otherwise. The objective of this analysis was to evaluate universal opt-out HIV and HCV screening in two EDs in San Diego. HIV screening for persons aged 13-64 years (excluding persons known to be HIV+ or reporting HIV testing within last 12 months) was implemented using a 4th generation HIV antigen/antibody assay; HCV screening was offered to persons born between 1945 and 1965. Over a period of 16 months, 12,575 individuals were tested for HIV, resulting in 33 (0.26%) new HIV diagnoses, of whom 30 (90%) were successfully linked to care. Universal screening also identified 74 out-of-care for >12-months HIV+ individuals of whom 50 (68%) were successfully relinked to care. Over a one-month period, HCV antibody tests were conducted in 905 individuals with a seropositivity rate of 9.9% (90/905); 61 seropositives who were newly identified or never treated for HCV had HCV RNA testing, of which 31 (51%) resulted positive (3.4% of all participants, including 18 newly identified RNA positives representing 2% of all participants), and 13/31 individuals (42%) were linked to care. The rate of newly diagnosed HCV infections exceeded the rate of newly diagnosed HIV infections by >7-fold, underlining the importance of HCV screening in EDs.

Reasons Why Young Men Who Have Sex with Men Report Not Using HIV Pre-Exposure Prophylaxis: Perceptions of Burden, Need, and Safety

Uptake of pre-exposure prophylaxis (PrEP) has dramatically increased but remains well below the estimated number of individuals who could benefit from PrEP in the United States, and uptake remains limited among young men who have sex with men (YMSM) and MSM of color. Reasons for not adopting PrEP as a prevention strategy among those at elevated risk for HIV is an important area of inquiry that could advise efforts to better position PrEP as an active part of prevention programs. As part of a mixed methods study investigating experiences with repeat HIV testing, we identified main themes emerging from in-depth interview data pertaining to reasons why YMSM report not using PrEP, among YMSM with frequent access to HIV testing services. Themes from 14 in-depth interviews with predominantly Latino MSM for not using PrEP included perceived burden of daily dosing, feeling that risk was not high enough to warrant PrEP, and beliefs that PrEP would have severe adverse events affecting the kidneys and bones. Less prominent but noteworthy themes included stigma as a PrEP user, social or provider influence on decisions not to use PrEP, and preference for current prevention strategy. No differences in PrEP discourse were noted across those at different levels of HIV risk. Results suggest that efforts are needed to engage communities and individuals around PrEP-related education, facilitate risk evaluation, and reduce PrEP stigma. New formulations and nondaily regimens may also be of particular interest to YMSM who may perceive daily PrEP regimens as highly burdensome.

HPTN 067/ADAPT: Correlates of Sex-Related Pre-exposure Prophylaxis Adherence, Thai Men Who Have Sex With Men, and Transgender Women, 2012-2013

BACKGROUND

We identified correlates of sex-related pre-exposure prophylaxis (PrEP) adherence in HPTN067/ADAPT, a phase 2, open-label feasibility study of daily and nondaily regimens of emtricitabine/tenofovir disoproxil fumarate (FTC/TDF)-based PrEP, among Thai men who have sex with men (MSM), and transgender women (TGW), Bangkok.

METHODS

Participants were randomly assigned to one of three self-administered dosing regimens for 24 weeks: daily, time-driven, or event-driven. Demographic and behavioral information was obtained at screening. Pill-container opening was recorded with electronic dose monitoring, and self-reported information on PrEP use, sex events, and substance use was obtained during weekly interviews to confirm dose data. Sex-related PrEP adherence was calculated as the proportion of sex events covered by PrEP use (at least one tablet taken within 4 days before sex and at least one tablet taken within 24 hours after sex) to total sex events. We used multivariate modeling with sex event as the unit of analysis to evaluate correlates associated with sex-related PrEP adherence.

RESULTS

Among 178 MSM and TGW, sex-related PrEP adherence was similar in the daily and time-driven arms (P = 0.79), both significantly greater than the event-driven arm (P = 0.02 compared to daily). Sex-related PrEP adherence by those reporting stimulant use (74.2%) was similar to those reporting other nonalcohol drug use (76.3%, P = 0.80), but lower than those reporting no substance use (84.6%, P = 0.04). In a multivariable model, randomization to the event-driven arm, a higher prestudy number of reported sex events, and use of stimulant drugs were associated with significantly lower sex-related PrEP adherence.

CONCLUSION

Adherence was influenced by treatment schedule and adversely affected by nonalcoholic substance use. Regardless of these factors, Thai MSM and TGW maintained high adherence levels to oral PrEP dosing regimens and coverage of sexual exposures.