Comparing Self-Report Pre-Exposure Prophylaxis Adherence Questions to Pharmacologic Measures of Recent and Cumulative Pre-Exposure Prophylaxis Exposure

Sexual Identity Development and Social Ecological Facilitators and Barriers of PrEP Uptake and Adherence Among Latinx Men Who Have Sex with Men

Latinx gay, bisexual, and other men who have sex with men (LMSM) report lower pre-exposure prophylaxis (PrEP) use than their white, non-Latinx counterparts. We hypothesize that this disparity is partially attributable to social ecological factors that can be addressed via prevention interventions. In this retrospective study, we first examined data from 253 LMSM to determine whether theorized associations existed between acquisition of a PrEP prescription (uptake) in relation to several social ecological factors based on a conceptual framework of determinants of access to and uptake of PrEP for LMSM. We also explored relations between frequency of PrEP use (adherence) and social ecological factors with a subsample of 33 LMSM who had initiated PrEP 12 months prior to assessment. In this study, individual-level factors from this framework included age and socioeconomic status. Perceived access to medical care represented both individual- and community-level determinants of PrEP uptake and adherence. Interpersonal-level factors were social support and relationship status. Structural/cultural-level factors were sexual identity development status, the masculinity norm of heterosexual self-presentation, traditional Latinx masculine gender role beliefs of machismo and caballerismo, racial identity, and immigration status. Results indicated that older men and those who endorsed the synthesis/integration status of sexual identity development were more likely to acquire a PrEP prescription during their lifetime in comparison to peers. PrEP adherence was linked with being older, reporting higher socioeconomic status, reporting more appraisal social support, self-identifying as white-Latinx, being U.S.-born, and endorsing less sexual identity uncertainty and more heterosexual self-presentation. Results specify modifiable factors that may inform tailored, community-based prevention efforts to increase PrEP use and decrease existing HIV/AIDS disparities among LMSM.

Characterizing Interest in and Uptake of Preexposure Prophylaxis for HIV Prevention Among Men in a US State Correctional System

BACKGROUND

People experiencing incarceration are disproportionately impacted by HIV and are potential candidates for HIV preexposure prophylaxis (PrEP). We explored factors associated with PrEP interest and PrEP uptake and described barriers to PrEP uptake among incarcerated men in a state correctional system.

METHODS

From September 2019 to July 2022, incarcerated men at the Rhode Island Department of Corrections were screened for PrEP eligibility and referred to a PrEP initiation study. We used bivariate analyses and multivariable logistic regression models to explore factors associated with PrEP interest and uptake in the screening sample.

RESULTS

Of the men screened and determined to be eligible for PrEP, approximately half (50%) were interested in taking PrEP. Individuals identifying as men who have sex with men (adjusted odds ratio, 4.46; 95% confidence interval, 1.86-11.4) and having multiple female sex partners (adjusted odds ratio, 2.98; 95% confidence interval, 1.47-6.27) were more likely to express interest in PrEP (interested/not interested) than those not reporting these behavioral factors. Preexposure prophylaxis uptake (yes/no) was 38%. Lack of PrEP interest, low self-perceived risk of HIV acquisition, and unpredictable lengths of incarceration were the most frequently encountered barriers to PrEP uptake.

CONCLUSIONS

Men reporting sexual transmission behaviors were more interested in PrEP and had higher uptake than other men. Preexposure prophylaxis interest and HIV risk factors were both moderately high, which suggests that men experiencing incarceration should be screened for and offered PrEP as part of standard clinical care. Study findings have important implications for research and practice to adapt PrEP care to correctional systems.

Sample Matrices for Mass Spectrometry-Based Adherence Monitoring: A Systematic Critical Review

BACKGROUND

Analytical monitoring of adherence using mass spectrometry (MS) plays an important role in clinical toxicology. Unambiguous detection of drugs (of abuse) and/or their metabolites in body fluids is needed to monitor intake of medication as prescribed or to monitor abstinence as a follow-up to detoxification procedures. This study focused on the advantages and disadvantages of different sample matrices used for MS-based adherence monitoring.

METHODS

Relevant articles were identified through a literature search in the PubMed database. English articles published between January 01, 2017, and December 31, 2022, were selected using the keywords "adherence assess*" or "adherence monit*" or "compliance assess*" or "compliance monit*" in combination with "mass spectrom*" in the title or abstract.

RESULTS

A total of 51 articles were identified, 37 of which were within the scope of this study. MS-based monitoring was shown to improve patient adherence to prescribed drugs. However, MS analysis may not be able to assess whether treatment was rigorously followed beyond the last few days before the sampling event, except when hair is the sample matrix. For medication adherence monitoring, blood-based analyses may be preferred because reference plasma concentrations are usually available, whereas for abstinence control, urine and hair samples have the advantage of extended detection windows compared with blood. Alternative sample matrices, such as dried blood samples, oral fluid, and exhaled breath, are suitable for at-home sampling; however, little information is available regarding the pharmacokinetics and reference ranges of drug (of abuse) concentrations.

CONCLUSIONS

Each sample matrix has strengths and weaknesses, and no single sample matrix can be considered the gold standard for monitoring adherence. It is important to have sufficient information regarding the pharmacokinetics of target substances to select a sample matrix in accordance with the desired purpose.

Low daily oral PrEP adherence and low validity of self-report in a randomized trial among PWID in Ukraine

BACKGROUND

The efficacy of daily oral pre-exposure prophylaxis (PrEP) in preventing HIV transmission among people who inject drugs (PWID) was demonstrated over a decade ago. However, only a few studies among PWID have since measured PrEP adherence using laboratory markers.

METHODS

In this trial, we randomized recently injecting PWID in Kyiv, Ukraine, to receive daily oral TDF/FTC with or without SMS reminders. Enrollment and PrEP initiation took place at an HIV clinic. Subsequent visits at months 1, 3, and 6 were conducted at a community harm reduction center and included a structured interview, adherence counseling, PrEP dispensing, and dried blood spot collection. PrEP adherence was assessed using standard self-reported measures and TDF/FTC biomarkers.

RESULTS

A total of 199 PWID (99 SMS, 100 No-SMS) were enrolled, of whom 24 % were women, with a median age of 37. At month 6, 79.4 % (158/199) of participants were retained, with 84 % (133/158) reporting opioid injection and 20 % (31/158) reporting stimulant injection in the past 30 days. 77 % (122/158) reported taking >95 % of PrEP doses in the past month, and 87 % reported taking the last dose within 2 days. Tenofovir diphosphate was detected in 17 % (28/158) of participants, and emtricitabine triphosphate was detected in 25 % (40/158). Only 3 % (5/158) had metabolite levels indicative of consistent PrEP uptake at 4+ doses per week. There was no association between the SMS intervention and TDF/FTC metabolite detection.

CONCLUSION

Adherence to daily oral PrEP among actively injecting PWID, without daily supervision or incentives, was extremely low, despite supportive counseling and SMS reminders. We also observed a high rate of discordance between self-report and classification by a validated biomarker of adherence. Given the scarcity of evidence and emerging data suggesting low oral PrEP adherence among PWID, additional implementation studies with TDF/FTC biomarkers are needed to study whether a sufficient level of adherence to daily PrEP is attainable among PWID, especially as long-acting injectable PrEP offers a promising alternative.

Performance of Multiple Adherence Measures for pre-exposure Prophylaxis (PrEP) Among Young Women in Kenya

Understanding PrEP adherence is key in the formulation of HIV prevention strategies; however, measurement of adherence can be challenging. We compared multiple adherence measures in a two-year study of young Kenyan women at high risk of HIV acquisition. Among 289 participants, concordance between electronic adherence monitoring (EAM) and tenofovir diphosphate (TFV-DP) in dried blood spots ranged from 57 to 72% depending on selected thresholds. Using area under the receiver operating curve, discrimination of quantifiable TFV-DP was high at 0.85 with EAM and low at 0.49-0.54 for multiple self-reported measures. Correlation between EAM and self-reported measures was low (r < 0.11) although correlation within self-reported measures was moderate (r > 0.69). These findings indicate that both TFV-DP and EAM are useful PrEP adherence tools. Adherence would benefit from better availability of less expensive versions of both measurement tools. Additionally, further research on TFV-DP thresholds is needed to inform interpretation and use in understanding PrEP adherence in this population.

Urine point-of-care tenofovir test demonstrates strong predictive clinical and research utility

BACKGROUND

Preexposure prophylaxis (PrEP) significantly reduces HIV infection risk but is dependent on adherence. Available approaches to measuring adherence have limitations related to accuracy, cost, practicality, and timeliness. This study compared the performance of two methods implementable in clinics and research studies [interview and urine point of care (POC) assay] to the gold-standard for measuring recent and longer term adherence in dried blood spots (DBS).

METHODS

Participants were recruited from RADAR, a cohort study of young MSM, or via online advertisements. At 3 monthly visits, an interviewer administered 7-day timeline follow-back (TLFB) questionnaire, DBS samples were tested for tenofovir-diphosphate (TFV-DP) to estimate average dosing over the prior month and emtricitabine-triphosphate (FTC-TP) to assess recent dosing (past 2-3 days), and a urine POC TFV test to qualitatively assess recent adherence (past 4 days).

RESULTS

Eighty-three PrEP users contributed 163 observations. At visit 1, self-reported adherence was 86% (4+ doses in last 7 days), versus urine TFV (74%), DBS FTC-TP (76%), and DBS TFV-DP (69%). The objective measures of short-term adherence performed similarly well in predicting longer term adherence. In multivariable logistic regression analyses, the urine assay was a significant predictor of DBS TFV-DP (adjusted OR = 19.4, P  < 0.0001); self-report did not add significantly.

CONCLUSION

The urine POC TFV assay had excellent predictive values for adherence and self-report did not add significantly to prediction. The POC assay provides results in several minutes to enable same-visit counseling, requires no specialized training, and is projected to be low-cost.

Stand-alone model for delivery of oral HIV pre-exposure prophylaxis in Kenya: a single-arm, prospective pilot evaluation

INTRODUCTION

The delivery of daily, oral HIV pre-exposure prophylaxis (PrEP) at private pharmacies may overcome barriers to PrEP delivery at public healthcare facilities, including HIV-associated stigma, long wait times and overcrowding.

METHODS

At five private, community-based pharmacies in Kenya, a care pathway for PrEP delivery (ClinicalTrials.gov: NCT04558554) was piloted-the first of its kind in Africa. Pharmacy providers screened clients interested in PrEP for HIV risk, then used a prescribing checklist to identify clients without medical conditions that might contraindicate PrEP safety, counsel them on PrEP use and safety, conduct provider-assisted HIV self-testing and dispense PrEP. For complex clinical cases, a remote clinician was available for consultation. Clients who did not meet the checklist criteria were referred to public facilities for free services delivered by clinicians. Pharmacy providers dispensed a 1-month PrEP supply at initiation and a 3-month supply thereafter at a client fee of 300 KES (∼$3 USD) per visit.

RESULTS

From November 2020 to October 2021, pharmacy providers screened 575 clients, identified 476 who met the prescribing checklist criteria and initiated 287 (60%) on PrEP. Among pharmacy PrEP clients, the median age was 26 years (IQR 22-33) and 57% (163/287) were male. The prevalence of behaviours associated with HIV risk among clients was high; 84% (240/287) reported sexual partners with unknown HIV status and 53% (151/287) reported multiple sexual partners (past 6 months). PrEP continuation among clients was 53% (153/287) at 1 month, 36% (103/287) at 4 months and 21% (51/242) at 7 months. During the pilot observation period, 21% (61/287) of clients stopped and restarted PrEP and overall pill coverage was 40% (IQR 10%-70%). Nearly, all pharmacy PrEP clients (≥96%) agreed or strongly agreed with statements regarding the acceptability and appropriateness of pharmacy-delivered PrEP services.

CONCLUSIONS

Findings from this pilot suggest that populations at HIV risk frequently visit private pharmacies and PrEP initiation and continuation at pharmacies is similar to or exceeds that at public healthcare facilities. Private pharmacy-based PrEP delivery, conducted entirely by private-sector pharmacy staff, is a promising new delivery model that has the potential to expand PrEP reach in Kenya and similar settings.

Socio-behavioral correlates of pre-exposure prophylaxis use and correct adherence in men who have sex with men in West Africa

BACKGROUND

Multiple barriers compromise pre-exposure prophylaxis (PrEP) engagement (i.e., use and adherence) in men who have sex with men (MSM). In low/middle-income countries, little is known about PrEP engagement in this population. In West Africa, the CohMSM-PrEP study was one of the rare interventions providing PrEP to MSM. We estimated PrEP use and correct adherence rates in CohMSM-PrEP, together with associated factors over time.  METHODS: CohMSM-PrEP recruited MSM in four community-based clinics in Mali, Côte d'Ivoire, Burkina Faso, and Togo. Quarterly follow-up included collecting socio-behavioral data, and providing a comprehensive HIV prevention package, PrEP (daily or event-driven), and peer educator (PE)-led counselling. Using repeated measures, multivariate generalized estimating equations models were used to identify factors associated with self-reported i) PrEP use and ii) correct PrEP adherence during participants' most recent anal intercourse (defined as four pills/week for daily users and 2 + 1 + 1 for event-driven users).

RESULTS

Five hundred twenty participants were included with a median follow-up time of 12 months (IQR 6-21). Of the 2839 intercourses declared over the follow-up period, PrEP use was self-reported for 1996 (70%), and correct PrEP adherence for 1461 (73%) of the latter. PrEP use was higher in participants who also attended participating clinics outside of scheduled visits (adjusted odds ratio (aOR) [95% Confidence Interval, CI], p-value; 1.32[1.01-1.71], 0.040), and in those who practiced condomless anal sex (1.86[1.54-2.24], < 0.001). Correct adherence was higher in those who often contacted PE outside of scheduled visits (2.16[1.01-4.64], 0.047) and in participants who adopted receptive/versatile sexual positions with stable partners (1.36[1.03-1.81], 0.030). Instead, after an interaction effect between financial situation and regimen was tested, it was lower in event-driven users with a difficult/very difficult financial situation (comfortable/just making ends meet & daily, 4.19[2.56-6.86], < 0.001; difficult/very difficult & daily, 6.47[4.05-10.30], < 0.001; comfortable/just making ends meet & event-driven, 1.63[1.22-2.17], 0.001), and in participants who felt alone (0.76[0.58-0.99], 0.042).

CONCLUSIONS

Community-based clinic attendance and PE contact outside of scheduled visits were both associated with higher PrEP engagement, but some socially and economically marginalized participants struggled with adherence. As scale-up continues in West Africa, we recommend implementing community-based interventions and providing extra support for vulnerable users to ensure adequate PrEP engagement.

The Potential of Telecommunication Technology to Address Racial/Ethnic Disparities in HIV PrEP Awareness, Uptake, Adherence, and Persistence in Care: A Review

Pre-exposure prophylaxis (PrEP) is highly effective in preventing new HIV infection, but uptake remains challenging among Black and Hispanic/Latino persons. The purpose of this review was to understand how studies have used electronic telecommunication technology to increase awareness, uptake, adherence, and persistence in PrEP care among Black and Hispanic/Latino persons and how it can reduce social and structural barriers that contribute to disparities in HIV infection. Of the 1114 articles identified, 10 studies were eligible. Forty percent (40%) of studies focused on Black or Hispanic/Latino persons and 80% addressed social and structural barriers related to PrEP use such as navigation or access to PrEP. Mobile health designs were more commonly used (50%) compared to telehealth (30%) and e-health (20%) designs. There is a need to increase the development of telecommunications interventions that address the needs of Black and Hispanic/Latino persons often challenged with uptake and adherent use of PrEP.

Optimizing an mHealth Intervention to Improve Uptake and Adherence to HIV Pre-exposure Prophylaxis in Young Transgender Women: Protocol for a Multi-Phase Trial

BACKGROUND

Vulnerable adolescents and emerging adults (aged 18-29 years), particularly young transgender women, are among the fastest-growing HIV positive populations worldwide. Thailand has the highest adult HIV seroprevalence in Asia, with a rate of infection among this population of 18%. Widespread technology offers opportunities for innovative mobile health (mHealth) interventions. Pre-exposure prophylaxis (PrEP) is an efficacious HIV prevention strategy recommended for at-risk individuals. PrEP is highly effective when taken as prescribed, but uptake and adherence have been low, with high discontinuation rates among youth.

OBJECTIVE

We propose to develop and pilot a multi-component, technology-based intervention to promote PrEP usage. We will adapt an existing 2-session, technology-delivered, motivational interviewing-based intervention to focus on PrEP use in transgender women in Thailand. We call this the Motivational Enhancement System for PrEP Uptake and Adherence (MES-PrEP). We will also refine and enhance YaCool, a mobile app with integrated text messaging developed and used clinically by our Thai team. The new version of the app is called Enhanced YaCool, and it enables self-management of gender and sexual health (including PrEP). Our primary aim is to develop and assess the preliminary efficacy of this mHealth intervention.

METHODS

We will utilize a multiphase optimization strategy (MOST) to identify the most effective intervention component or combination of components to improve PrEP usage in Thai transgender women. The study includes two phases: phase I (R21) includes qualitative interviews with key stakeholders to explore barriers and facilitators of PrEP usage through thematic analysis to inform intervention adaptation. Following this, we will adapt and beta-test MES-PrEP and Enhanced YaCool for functionality and feasibility using a community advisory board of HIV-negative Thai transgender women. In phase II (R33), we will conduct a MOST design-based trial to evaluate the feasibility, acceptability, and preliminary efficacy of MES-PrEP and Enhanced YaCool. Eighty HIV-negative participants who are currently taking PrEP and 80 participants who are not will be randomized to four conditions: (1) standard PrEP counseling (the control condition); (2) MES-PrEP and standard PrEP counseling; (3) Enhanced YaCool and standard PrEP counseling; and (4) MES-PrEP, Enhanced YaCool, and standard PrEP counseling. Feasibility and acceptability of the intervention will be assessed through usage patterns and the System Usability Scale. Preliminary impact will be assessed by evaluating the proportion of participants who initiate PrEP and their level of adherence to PrEP. Assessments will be at baseline and 1, 3, 6, 9, and 12 months postintervention. Biomarkers of adherence to PrEP, HIV, and other sexually transmitted infections will be collected.

RESULTS

Upon project completion, we will have an optimized mHealth intervention to support the use of PrEP by transgender women that will be ready for testing in a larger efficacy trial.

CONCLUSIONS

Even though transgender women in Thailand face increasing risks of HIV, few interventions have targeted them. Effective developmentally and culturally tailored interventions are needed to prevent HIV transmission in this high-risk population.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05262426; https://clinicaltrials.gov/ct2/show/NCT05262426.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/37659.

Rate and Predictors of Ineffective HIV Protection in African Men Who Have Sex with Men Taking Pre-Exposure Prophylaxis

We investigated the rate and predictors of ineffective HIV protection in men who have sex with men (MSM) taking pre-exposure prophylaxis (PrEP) in a prospective cohort study from November 2017 to November 2020 in Mali, Côte d'Ivoire, Burkina Faso, and Togo. MSM had to be 18 years or older and at high risk of HIV infection to participate. They also received a comprehensive sexual health prevention package, including PrEP, in community-based clinics as part of the cohort study. Using socio-behavioral/clinical data, HIV protection during their most recent anal intercourse with a male partner was categorized as effective or ineffective (i.e., incorrect PrEP adherence and no condom use). Seventeen percent (500/2839) of intercourses were ineffectively protected for the 520 study participants. Predictors of ineffective HIV protection included being an event-driven user with financial difficulties, having a high alcohol misuse score, and not being a member of a community association. PrEP programs in West Africa must be tailored to socially vulnerable MSM who struggle to adopt PrEP.

Adherence to Daily Oral TDF/FTC for PrEP in Community Health Center Populations: The Sustainable Health Center Implementation PrEP Pilot (SHIPP) Study

The prevention effectiveness of oral preexposure prophylaxis (PrEP) is highly dependent on medication adherence but no validated longer term PrEP adherence measures are readily available for use by primary care clinicians caring for diverse populations. We compared two self-report measures (number of doses missed in past 7 days and day-by-day past week pill taking) to results of tenofovir concentrations in dried blood spot (DBS) samples at quarterly visits over the first 12 months of PrEP use. 1420 men and women in five US community health centers enrolled in a medication adherence substudy. For 3, 6, 9 and 12 months, the respective percentages of persons with self-report vs DBS levels consistent having taken all 7 doses in the week prior were 71% (51%), 70% (47%), 71% (46%) and 69% (44%). Conversely, the percentage of participants reporting taking 0-1 doses in the week prior by self-report vs DBS drug levels at 3, 6, 9 and 12 months consistent with this level of nonadherence of 6% (9%), 5% (10%), 8% (9%), and 9% (15%). The estimated risk of low adherence (estimated 0-1 doses in the week prior) was higher for participants of Black (RR 1.60, CI 1.09-2.34) or "Other" race (RR 1.62, CI 0.99-2.65) compared with participants of White race; being a transgender female (RR 2.31, CI 1.33-4.02) compared to men who have sex with men; or enrollment at a study site with less experience in the provision of PrEP. The estimated risk of low adherence by DBS was lower for participants with a higher number of sex partners in the past 3 months and those having a bachelor's degree or higher. More work is needed to provide clinicians with measures to assess medication adherence in diverse US populations being prescribed PrEP to support its effective use in reducing HIV acquisition in individuals and at the community level.

Socio-behavioral factors related to PrEP non-adherence among gay male PrEP users living in California and New York: A behavioral theory informed approach

One effective preventative measure to reduce the number of new HIV infections is through the uptake of daily oral HIV pre-exposure prophylaxis (PrEP). Although previous clinical trials have proven the effectiveness of on-demand PrEP uptake, daily PrEP uptake is the most popular prevention method among PrEP users and is still recommended by most healthcare professionals and organizations. Informed by the integrative model of behavioral prediction, the current study examined the socio-behavioral factors associated with PrEP non-adherence. The present study conducted a cross-sectional survey of 210 gay male daily PrEP users living in California and New York. The results showed more than two-thirds of the sample indicated that they had skipped taking PrEP within the last 30 days, averaging around four to five missed doses. General attitudes toward desirable and undesirable outcomes, perceived behavioral control, and social-level barriers were associated with daily PrEP uptake non-adherence. The findings highlight providers' role in PrEP adherence and the importance of habit-forming, which can be enhanced by cost-effective strategies and technological innovations.

COVID-19-Related Stressors, Sex Behaviors, and HIV Status Neutral Care Among Black Men Who Have Sex With Men and Transgender Women in Chicago, USA

BACKGROUND

COVID-19 has disproportionately impacted vulnerable populations, including Black men who have sex with men (BMSM) and transgender women (BTW). We investigated associations of COVID-19 stressors and sex behaviors with pre-exposure prophylaxis (PrEP) and antiretroviral therapy (ART) among BMSM and BTW.

METHODS

As part of the Neighborhoods and Networks (N2) study, we conducted virtual interviews during peak COVID-19 infectivity in Chicago among BMSM and BTW (April-July 2020). Survey questions included multilevel COVID-19 stressors, sex behaviors, and current PrEP/ART use and access. Poisson regressions were used to examining relationships between COVID-19 stressors, sex behaviors, and PrEP/ART use/access.

RESULTS

Among 222 participants, 31.8% of participants not living with HIV reported current PrEP use and 91.8% of participants living with HIV reported ART use during the pandemic. Most (83.3% and 78.2%, respectively) reported similar or easier PrEP and ART access during the pandemic. Physical stress reaction to COVID-19 [adjusted prevalence ratio [aPR] = 2.1; confidence interval (CI): 1.3 to 3.5] and being in close proximity with someone diagnosed with COVID-19 (aPR = 1.7; CI: 1.1 to 2.8) were associated with current PrEP use. Intimate partner violence (aPR = 2.7; CI: 1.0 to 7.2) and losing health insurance (aPR = 3.5; CI: 1.1 to 10.7) were associated with harder ART access. Travel-related financial burden was associated with harder access in PrEP (aPR = 3.2; CI: 1.0 to 10.1) and ART (aPR = 6.2; CI: 1.6 to 24.3).

CONCLUSIONS

Multiple COVID-19 stressors were found to interfere with PrEP and ART use and access among BMSM and BTW. Contextually relevant strategies (eg, promoting telehealth and decreasing transportation burden) to address COVID-19 stressors and their sequelae should be considered to minimize disruption in HIV biomedical interventions.

Plasma and intracellular pharmacokinetics of tenofovir disoproxil fumarate and emtricitabine in transgender women receiving feminizing hormone therapy

BACKGROUND

Transwomen have an increased risk of HIV acquisition compared with other adults. Drug-drug interactions between pre-exposure prophylaxis (PrEP) and gender-affirming therapy are cited as a reason for poor PrEP uptake among transwomen. We evaluated plasma tenofovir and emtricitabine pharmacokinetics and their active intracellular anabolites, tenofovir-diphosphate and emtricitabine-triphosphate, in transwomen receiving feminizing hormones.

METHODS

We enrolled HIV-negative transwomen (≥19 years) not receiving PrEP. Participants took oral tenofovir disoproxil fumarate/emtricitabine 300/200 mg daily for 14 days. Plasma was collected at 0 h (pre-dose), 0.5, 1, 2, 3, 4, 6, 8 and 12 h on day 14 post-tenofovir disoproxil fumarate/emtricitabine dose. The plasma AUC0-24 was calculated using the trapezoidal rule and compared with historical HIV-negative cisgender adults as geometric mean ratios (GMRs, 90% CI). Secondarily, tenofovir-diphosphate and emtricitabine-triphosphate from PBMCs collected at 0 h and 12 h were reported descriptively as geometric means (90% CI). Clinical trials registration: NCT03270969.

RESULTS

Among 15 transwomen (mean age 32 years), geometric mean tenofovir and emtricitabine plasma AUC0-24 were lower compared with controls: tenofovir, 2.10 versus 2.76 mg·h/L, GMR 0.76 (0.65-0.90), P = 0.01; emtricitabine, 9.15 versus 10.64 mg·h/L, GMR 0.86 (0.75-0.98), P = 0.07. Tenofovir-diphosphate and emtricitabine-triphosphate concentrations were higher than previously reported in the literature: 167.1 (146.6-190.5) fmol/106 cells and 15.4 (13.8-17.3) pmol/106 cells, respectively.

CONCLUSIONS

We observed lower plasma tenofovir and emtricitabine concentrations in transwomen compared with historical cisgender adults, yet intracellular tenofovir-diphosphate and emtricitabine-triphosphate concentrations were higher than previously reported in PBMCs. Understanding the differences of PrEP pharmacokinetics in plasma and tissue compartments and the resultant impact on efficacy remains important for transwomen.

Population-Level Effectiveness of HIV Pre-exposure Prophylaxis Among MSM and Transgender Persons With Bacterial Sexually Transmitted Infections

BACKGROUND

Pre-exposure prophylaxis (PrEP) is highly efficacious, but its effectiveness may be limited by poor adherence or discontinuation. Our objective was to estimate the effectiveness of real-world PrEP use in a population at increased risk of HIV infection.

SETTING

King County, Washington.

METHODS

We conducted a retrospective cohort study using sexually transmitted infection (STI) partner services (PS) interview data collected January 2014-August 2018 in King County, Washington, USA. During PS interviews, men who have sex with men and transgender persons who have sex with men were asked if they were taking PrEP. We linked STI PS data to HIV surveillance data to estimate HIV incidence among self-reported PrEP users vs. nonusers using Cox proportional hazards regression, adjusting for age, race/ethnicity, and calendar year.

RESULTS

Among 4368 individuals, 1206 (28%) were taking PrEP at the time of the PS interview. The median observation time was 14 months (interquartile range 6-23 months). Five (0.4%) of 1206 PrEP users and 97 (3%) of 2162 PrEP nonusers were subsequently diagnosed with HIV (P < 0.001). HIV incidence was lower among PrEP users than nonusers [0.17 vs. 1.86 cases per 100 person-years, adjusted hazards ratio 0.21 (95% confidence interval: 0.08 to 0.58)]. Latinx ethnicity, Native Hawaiian/Pacific Islander ethnicity, gonorrhea, and syphilis were also independently associated with higher HIV risk.

CONCLUSIONS

Self-reported PrEP use was associated with a 79% reduction in HIV incidence among men who have sex with men and transgender persons who have sex with men with STIs in King County.

The Value of Assessing Self-Reported and Biological Indicators of Outcomes in Evaluating HIV Programs

PURPOSE OF REVIEW

In this manuscript, we present recent findings concerning concordance and discrepancy between biological measures and self-reports of these three outcomes of HIV programs: HIV status, adherence to antiretroviral medications (ARVs) and use of and adherence to pre-exposure prophylaxis medication (PrEP), and condom use/unprotected sex.

RECENT FINDINGS

Recent studies suggest that three successive rapid HIV tests (for those whose first test in positive) might be reasonably inexpensive and valid biological data to collect to combine with self-reports of HIV status, dried blood spots sufficiently affordable to combine with self-reports of adherence to ARVs and use of or adherence to PrEP, and that the discrepancy between self-reports of condom use and biomarkers of unprotected sex may be relatively small in high-income countries. Additional work on assessment of incorrect condom usage and breakage, standardized self-report measures of condom use, and more private data collection methodologies in low-income settings might reduce the recent observed discrepancies even further. Concordance between self-reports of HIV and biomarkers indicating HIV positive status has varied considerably, with much lower rates in low-income countries, where the stigma of HIV is still very high. Recommendation is for combining self-report data with the results of three successive rapid tests for those testing positive. For adherence, again agreement between self-reports and a variety of more objective and/or biological measures is only moderate. Dried blood spots (DBS) may be sufficiently inexpensive in low-resource settings that this may be the best biological method to combine with self-reports. In publications over the last 8 years, the discrepancy between self-reports of condom use and biomarkers for unprotected sex may be even lower than 20% after controlling for other features of the study, particularly in high-income countries. Our results suggest that more careful assessment of incorrect condom use and breakage as reasons other than intentional misreporting should be investigated more carefully and that more private data collection methods such as audio, computer-assisted self-interviewing (ACASI) might be employed more often in low-resource settings to reduce this discrepancy in those settings further. In addition, further analysis of the discrepancy between self-reports of condom use and biomarkers should be conducted of published studies using the correct calculation methods to be more certain of these findings.

Brief Report: Discrepancies Between Self-Reported Adherence and a Biomarker of Adherence in Real-World Settings

BACKGROUND

Pre-exposure prophylaxis (PrEP) is only effective in preventing new HIV infections when taken consistently. In clinical practice, asking a patient about their adherence (self-report) is the predominant method of assessing adherence to PrEP. Although inexpensive and noninvasive, self-report is subject to social desirability and recall biases. Several clinical trials demonstrate a discrepancy between self-reported adherence and biomarker-based recent adherence. Less is known about the accuracy of self-report in real-world clinical settings. This brief report addresses this knowledge gap and describes the concordance between self-reported adherence and biomarker-based adherence in real-world clinical settings.

METHODS

A liquid chromatography-mass spectrometry urine test for tenofovir was developed and used clinically to detect recent nonadherence (no dose in at least 48 hours) for each individual. Two clinics' standard operating procedures recommend utilization of the urine-based adherence test for patients who self-report that they are not struggling with adherence. Those who self-report struggling with adherence receive enhanced adherence support without the need for additional testing. The number of results indicating recent nonadherence from these 2 clinics were analyzed to assess the concordance between self-reported adherence and biomarker-based adherence.

RESULTS

Across 2 clinics, 3987 tests were conducted from patients self-reporting as "adherent," and 564 [14.1%; 95% confidence interval (CI): 13.1% to 15.2%] demonstrated recent nonadherence with the liquid chromatography-mass spectrometry test. At clinic #1 in Florida, 3200 tests were conducted, and 465 (14.5%; 95% CI: 13.3% to 15.8%) demonstrated recent nonadherence. At clinic #2 in Texas, 787 tests were conducted, and 99 (12.6%; 95% CI: 10.4% to 14.9%) demonstrated recent nonadherence.

CONCLUSIONS

Utilization of biomarker-based adherence monitoring at these 2 clinics resulted in 564 additional patients receiving enhanced adherence support who otherwise would not have been identified as nonadherent to their prescribed PrEP regimen. These findings suggest that objective adherence monitoring can be used clinically to enable providers to identify nonadherent patients and allocate support services accordingly.

Implementation of pre-exposure prophylaxis programme in Spain. Feasibility of four different delivery models

BACKGROUND

Pre-exposure prophylaxis (PrEP) is an effective and cost-effective strategy for HIV prevention. Spain carried out an implementation study in order to assess the feasibility of implementing PrEP programmes within its heterogeneous health system.

METHODS

Observational longitudinal study conducted on four different types of health-care setting: a community centre (CC), a sexually transmitted infections clinic (STIC), a hospital-based HIV unit (HBHIVU) and a hospital-based STI unit (HBSTIU). We recruited gay, bisexual and other men who have sex with men (GBSM) and transgender women at risk of HIV infections, gave them PrEP and monitored clinical, behavioural PrEP-related and satisfaction information for 52 weeks. We collected perceptions on PrEP implementation feasibility from health-care professionals participating in the study.

RESULTS

A total of 321 participants were recruited, with 99.1% being GBMSM. Overall retention was 87.2% and it was highest at the CC (92.6%). Condom use decreased during the study period, while STIs did not increase consistently. The percentage of people who did not miss any doses of PrEP during the previous week remained at over 93%. No HIV seroconversions occurred. We observed overall decreases in GHB (32.5% to 21.8%), cocaine (27.5% to 21.4%), MDMA (25.7% to 14.3%), speed (11.4% to 5.7%) and mephedrone use (10.7% to 5.0%). The overall participant satisfaction with PrEP was 98.6%. Health-care professionals' perceptions of PrEP feasibility were positive, except for the lack of personnel.

CONCLUSIONS

PrEP implementation is feasible in four types of health-care settings. Local specificities have to be taken into consideration while implementing PrEP.

Tenofovir diphosphate concentrations in dried blood spots from pregnant and postpartum adolescent and young women receiving daily observed pre-exposure prophylaxis in sub-Saharan Africa

Background

Intracellular tenofovir diphosphate (TFV-DP) concentration in dried blood spots (DBSs) is used to monitor cumulative pre-exposure prophylaxis (PrEP) adherence. We evaluated TFV-DP in DBSs following daily oral PrEP (emtricitabine 200 mg/tenofovir diphosphate 300 mg) among pregnant and postpartum adolescent girls and young women (AGYW).

Methods

Directly observed PrEP was administered for 12 weeks in a pregnancy (14–24 weeks’ gestation, n = 20) and postpartum (6–12 weeks postpartum, n = 20) group of AGYW aged 16–24 years in sub-Saharan Africa. Weekly DBS TFV-DP was measured by validated liquid chromatography–tandem mass spectrometry assay. Week 12 TFV-DP distributions were compared between groups with Wilcoxon test. Population pharmacokinetic models were fit to estimate steady-state concentrations and create benchmarks for adherence categories. Baseline correlates of TFV-DP were evaluated.

Results

Median age was 20 (IQR, 19–22) years. Of 3360 doses, 3352 (>99%) were directly observed. TFV-DP median (IQR) half-life was 10 (7–12) days in pregnancy and 17 (14–21) days postpartum, with steady state achieved by 5 and 8 weeks, respectively. Observed median (IQR) steady-state TFV-DP was 965 fmol/punch (691–1166) in pregnancy versus 1406 fmol/punch (1053–1859) postpartum (P = .006). Modeled median steady-state TFV-DP was 881 fmol/punch (667–1105) in pregnancy versus 1438 fmol/punch (1178–1919) postpartum. In pooled analysis, baseline creatinine clearance was associated with observed TFV-DP concentrations.

Conclusions

TFV-DP in African AGYW was approximately one-third lower in pregnancy than postpartum. These Population-specific benchmarks can be used to guide PrEP adherence support in pregnant/postpartum African women.

Clinical Trials Registration

NCT03386578

Comparing self-reported medication adherence measures with hair antiretroviral concentration among people living with HIV in Guangxi, China

BACKGROUND

Antiretroviral adherence is essential to HIV treatment efficacy. Various self-reported measures are commonly used for assessing antiretroviral adherence. Limited data are available regarding the validity of those self-reported measures in comparison with long-term objective biomarkers of adherence measures such as hair measures.

METHODS

Self-reported adherence (frequency, percentage, and visual analog scale [VAS]) and hair tenofovir concentration were evaluated at a single time point from 268 people living with HIV in China. The responses to each of three self-reported measures were converted into percentage and then dichotomized as "optimal" (100%) vs. "suboptimal" (less than 100%) adherence. Two composite adherence scores (CAS) were created from the three self-reported measures: (1) an overall adherence was the average percentage of the three self-reported measures; (2) responses were termed optimal adherence if participants reporting optimal adherence in all three self-reported measures, while were termed suboptimal adherence. Hair tenofovir concentration was also dichotomized as "optimal" (above the limit of quantitation, 36 pg/mg) vs. "suboptimal" adherence (blow 36 pg/mg). Spearman correlation, kappa statistics, and logistic regression analysis were used to calculate the correlations, agreements, and predictions of self-reported measures with hair measure, respectively.

RESULTS

Overall adherence, but any of the three self-reported adherence, was correlated with hair tenofovir concentration (r = 0.13, p < 0.05). Self-reported optimal adherence in VAS and CAS measures were agreed with and predicted optimal adherence assessed by hair measure (Kappa = 0.107, adjusted OR = 1.88, 95% CI 1.03-3.45; Kappa = 0.109, adjusted OR = 1.80, 95% CI 1.02-3.18; all p < 0.05, respectively).

CONCLUSION

VAS may be a good individual self-reported measure for antiretroviral adherence, and CAS may be a good composite self-reported measure for antiretroviral adherence.

Sexually transmitted infections and sexual behaviors of men who have sex with men in an American Deep South PrEP clinic

HIV pre-exposure prophylaxis (PrEP) effectively prevents HIV acquisition among men who have sex with men (MSM), but PrEP uptake has been associated with sexually transmitted infections (STIs). The effect of PrEP on STIs in MSM in the Deep South of the United States is unknown. We performed a retrospective analysis of adult MSM at an American Deep South PrEP clinic to calculate the prevalence and incidence rate of bacterial STIs (chlamydia, gonorrhea, and syphilis) and identify associated risk factors by linking incident STI to patient-reported outcomes; 139 MSM accessed the clinic between 2014 and 2018 with baseline bacterial STI prevalence of 11%. Twenty-six of 81 eligible MSM on PrEP had incident STIs with an incidence rate of 33.1 cases per 100 person-years. Significantly higher proportions of high PrEP adherence, multiple sexual partners, and inconsistent condom use were seen in those with incident STI, and we identified MSM with both high PrEP adherence and multiple sexual partners as being at especially high risk for bacterial STIs (hazard ratio: 7.57, 95% confidence interval: 1.75–32.74). Bacterial STIs are common after initiating PrEP in this clinic, and MSM reporting high PrEP adherence and multiple sexual partners have a significant risk for incident STI. Highrisk sexual behaviors persisted after starting PrEP, highlighting the importance of ongoing, intensive sexual health screening and interventions.

HIV and bacterial sexually transmitted infections (STIs) disproportionately affect men who have sex with men (MSM) in the American Deep South. We found a high incidence among MSM after starting PrEP and identified MSM with high PrEP adherence and multiple sexual partners as highest risk for STI. Our findings signal a need for intensive, targeted sexual health counseling and intervention to curb the rise in STIs.