Patterns and correlates of PrEP drug detection among MSM and transgender women in the Global iPrEx Study

Effectiveness and safety of oral HIV preexposure prophylaxis for all populations

OBJECTIVE

Preexposure prophylaxis (PrEP) offers a promising new approach to HIV prevention. This systematic review and meta-analysis evaluated the evidence for use of oral PrEP containing tenofovir disoproxil fumarate as an additional HIV prevention strategy in populations at substantial risk for HIV based on HIV acquisition, adverse events, drug resistance, sexual behavior, and reproductive health outcomes.

DESIGN

Rigorous systematic review and meta-analysis.

METHODS

A comprehensive search strategy reviewed three electronic databases and conference abstracts through April 2015. Pooled effect estimates were calculated using random-effects meta-analysis.

RESULTS

Eighteen studies were included, comprising data from 39 articles and six conference abstracts. Across populations and PrEP regimens, PrEP significantly reduced the risk of HIV acquisition compared with placebo. Trials with PrEP use more than 70% demonstrated the highest PrEP effectiveness (risk ratio = 0.30, 95% confidence interval: 0.21-0.45, P < 0.001) compared with placebo. Trials with low PrEP use did not show a significantly protective effect. Adverse events were similar between PrEP and placebo groups. More cases of drug-resistant HIV infection were found among PrEP users who initiated PrEP while acutely HIV-infected, but incidence of acquiring drug-resistant HIV during PrEP use was low. Studies consistently found no association between PrEP use and changes in sexual risk behavior. PrEP was not associated with increased pregnancy-related adverse events or hormonal contraception effectiveness.

CONCLUSION

PrEP is protective against HIV infection across populations, presents few significant safety risks, and there is no evidence of behavioral risk compensation. The effective and cost-effective use of PrEP will require development of best practices for fostering uptake and adherence among people at substantial HIV risk.

Incidence of and temporal relationships between HIV, herpes simplex II virus, and syphilis among men who have sex with men in Bangkok, Thailand: an observational cohort

Background

High HIV incidence has been detected among men who have sex with men (MSM) in Thailand, but the relationship and timing of HIV, herpes simplex virus 2 (HSV-2), and syphilis is unknown. This analysis measures incidence, temporal relationships, and risk factors for HIV, HSV-2, and syphilis among at-risk MSM in the Bangkok MSM Cohort Study.

Methods

Between April 2006 and December 2010, 960 men negative for HIV, HSV-2, and syphilis at entry enrolled and contributed 12–60 months of follow-up data. Behavioral questionnaires were administered at each visit; testing for HIV antibody was performed at each visit, while testing for syphilis and HSV-2 were performed at 12 month intervals. We calculated HIV, HSV-2, and syphilis incidence, assessed risk factors with complementary log-log regression, and among co-infected men, measured temporal relationships between infections with Kaplan-Meier survival analysis and paired t-test.

Results

The total number of infections and incidence density for HIV, HSV-2, and syphilis were 159 infections and 4.7 cases/100 PY (95 % Confidence Interval (CI): 4.0–5.4), 128 infections and 4.5/100 PY (95 % CI: 3.9–5.5), and 65 infections and 1.9/100 PY (95 % CI: 1.5–2.5), respectively. Among men acquiring >1 infection during the cohort period, mean time to HIV and HSV-2 infection was similar (2.5 vs. 2.9 years; p = 0.24), while syphilis occurred significantly later following HIV (4.0 vs. 2.8 years, p < 0.01) or HSV-2 (3.8 vs. 2.8 years, p = 0.04) infection. The strongest independent predictor of any single infection in adjusted analysis was acquisition of another infection; risk of syphilis (Adjusted Hazards Ratio (AHR) = 3.49, 95 % CI: 1.89–6.42) or HIV (AHR = 2.26, 95 % CI: 1.47–3.48) acquisition during the cohort was significantly higher among men with incident HSV-2 infection. No single independent behavioral factor was common to HIV, HSV-2, and syphilis acquisition.

Conclusion

HIV and HSV-2 incidence was high among this Thai MSM cohort. However, acquisition of HIV and co-infection with either HSV-2 or syphilis was low during the time frame men were in the cohort. Evaluation of behavioral risk factors for these infections suggests different risks and possible different networks.

Self-reported Recent PrEP Dosing and Drug Detection in an Open Label PrEP Study

Monitoring adherence to pre-exposure prophylaxis (PrEP) is part of the recommended package for PrEP prescribing, yet ongoing concerns about how to do so confidently are exacerbated by gross discrepancies in reported and actual use in clinical trials. We evaluated concordance between reports of recent PrEP dosing collected via neutral interviewing and drug quantitation in the iPrEx open-label extension, where participants (n = 1172) had the choice to receive or not receive PrEP. Self-report of recent dosing (at least one PrEP dose in the past 3-day) was the most common report (84 % of participants), and among these 83 % did have quantifiable levels of drug. The vast majority of those reporting no doses in the past 3-day (16 % of the sample) did not have quantifiable levels of drug (82 %). Predictors of over-report of dosing included younger age and lower educational attainment. Monitoring recent PrEP use through neutral interviewing may be a productive approach for clinicians to consider in implementation of real-world PrEP. Strategies to capture longer term or prevention-effective PrEP use, particularly for younger cohorts, are needed.

Divergent adherence estimates with pharmacokinetic and behavioural measures in the MTN-003 (VOICE) study

INTRODUCTION

In the Microbicide Trial Network MTN-003 (VOICE) study, a Phase IIB pre-exposure prophylaxis trial of daily oral or vaginal tenofovir (TFV), product adherence was poor based on pharmacokinetic (PK) drug detection in a random subsample. Here, we sought to compare behavioural and PK measures of adherence and examined correlates of adherence misreporting.

METHODS

We included participants with PK and behavioural data from VOICE random subsample. Behavioural assessments included face-to-face interviews (FTFI), audio computer-assisted self-interviewing (ACASI) and pharmacy-returned product counts (PC). TFV concentrations < 0.31 ng/mL in plasma (oral group) and < 8.5 ng/swab in vaginal group were defined as "PK non-adherent." Logistic regression models were fit to calculate the combined predictive ability of the behavioural measures as summarized by area under the curve (AUC). Baseline characteristics associated with over-reporting daily product use relative to PK measures was assessed using a Generalized Linear Mixed Model.

RESULTS

In this random adherence cohort of VOICE participants assigned to active products, (N = 472), PK non-adherence was 69% in the oral group (N = 314) and 65% in the vaginal group (N = 158). Behaviourally, ≤ 10% of the cohort reported low/none use with any behavioural measure and accuracy was low (≤ 43%). None of the regression models had an AUC > 0.65 for any single or combined behavioural measures. Significant (p < 0.05) correlates of over-reporting included being very worried about getting HIV and being unmarried for the oral group; whereas for the vaginal group, being somewhat worried about HIV was associated with lower risk of over-reporting.

CONCLUSIONS

PK measures indicated similarly low adherence for the oral and vaginal groups. No behavioural measure accurately predicted PK non-adherence. Accurate real-time measures to monitor product adherence are urgently needed.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00705679.

Improving outpatient implementation of preexposure prophylaxis in men who have sex with men

BACKGROUND AND PURPOSE

Preexposure prophylaxis (PrEP) has been shown to decrease the transmission of human immunodeficiency virus (HIV) when used in high-risk populations including men who have sex with men. However, despite effectiveness, there is underutilization in the outpatient setting. This review aims to assess the facilitators and barriers to improve outpatient utilization.

METHODS

A systematic search of four databases, CINAHL, Ovid, Scopus, and PsychINFO, during March-May of 2015. A total of 22 articles were included for review.

CONCLUSIONS

Barriers to utilization were either patient or provider centered. Patient barriers included a significant lack of knowledge, stigma, risk-taking, and adherence. Provider barriers also included lack of knowledge of treatment and protocols as well as fears of resistance and behavior change. Facilitators included adherence regimens, education, and comprehensive care.

IMPLICATIONS FOR PRACTICE

Men who have sex with men are a high-risk population for HIV transmission. PrEP is successful in this subgroup at reducing transmission. Through education, nonjudgmental and comprehensive care providers can utilize PrEP to decrease transmission.

Preexposure Prophylaxis for HIV Infection Integrated With Municipal- and Community-Based Sexual Health Services

IMPORTANCE

Several randomized clinical trials have demonstrated the efficacy of preexposure prophylaxis (PrEP) in preventing human immunodeficiency virus (HIV) acquisition. Little is known about adherence to the regimen, sexual practices, and overall effectiveness when PrEP is implemented in clinics that treat sexually transmitted infections (STIs) and community-based clinics serving men who have sex with men (MSM).

OBJECTIVE

To assess PrEP adherence, sexual behaviors, and the incidence of STIs and HIV infection in a cohort of MSM and transgender women initiating PrEP in the United States.

DESIGN, SETTING, AND PARTICIPANTS

Demonstration project conducted from October 1, 2012, through February 10, 2015 (last date of follow-up), among 557 MSM and transgender women in 2 STI clinics in San Francisco, California, and Miami, Florida, and a community health center in Washington, DC. Data were analyzed from December 18, 2014, through August 8, 2015.

INTERVENTIONS

A combination of daily, oral tenofovir disoproxil fumarate and emtricitabine was provided free of charge for 48 weeks. All participants received HIV testing, brief client-centered counseling, and clinical monitoring.

MAIN OUTCOMES AND MEASURES

Concentrations of tenofovir diphosphate in dried blood spot samples, self-reported numbers of anal sex partners and episodes of condomless receptive anal sex, and incidence of STI and HIV acquisition.

RESULTS

Overall, 557 participants initiated PrEP, and 437 of these (78.5%) were retained through 48 weeks. Based on the findings from the 294 participants who underwent measurement of tenofovir diphosphate levels, 80.0% to 85.6% had protective levels (consistent with ≥4 doses/wk) at follow-up visits. African American participants (56.8% of visits; P = .003) and those from the Miami site (65.1% of visits; P < .001) were less likely to have protective levels, whereas those with stable housing (86.8%; P = .02) and those reporting at least 2 condomless anal sex partners in the past 3 months (88.6%; P = .01) were more likely to have protective levels. The mean number of anal sex partners declined during follow-up from 10.9 to 9.3, whereas the proportion engaging in condomless receptive anal sex remained stable at 65.5% to 65.6%. Overall STI incidence was high (90 per 100 person-years) but did not increase over time. Two individuals became HIV infected during follow-up (HIV incidence, 0.43 [95% CI, 0.05-1.54] infections per 100 person-years); both had tenofovir diphosphate levels consistent with fewer than 2 doses/wk at seroconversion.

CONCLUSIONS AND RELEVANCE

The incidence of HIV acquisition was extremely low despite a high incidence of STIs in a large US PrEP demonstration project. Adherence was higher among those participants who reported more risk behaviors. Interventions that address racial and geographic disparities and housing instability may increase the impact of PrEP.

Pre-exposure prophylaxis for men and transgender women who have sex with men in Brazil: opportunities and challenges

INTRODUCTION

The World Health Organization recently released guidelines on the use of pre-exposure prophylaxis (PrEP) for prevention of HIV infection among men and transgender women (TGW) who have sex with men based on results of randomized clinical trials. The aim of this commentary is to discuss the opportunities and challenges of incorporating PrEP into the Brazilian continuum of HIV care and prevention for men who have sex with men (MSM) and TGW.

DISCUSSION

Key aspects of the AIDS epidemic among MSM and TGW in Brazil and the comprehensive Brazilian response to the epidemic are presented. The universal access to health care provided through the Brazilian Unified Health System (SUS) and the range of prevention and care services already available countrywide to HIV-positive individuals and at-risk MSM and TGW are identified as the main facilitators for the implementation of PrEP. Limited PrEP awareness among MSM, TGW and health care providers, low HIV testing frequency and low HIV risk perception among MSM and TGW represent the core challenges to be addressed. Data generated by demonstration projects in Brazil will provide an important contribution to PrEP rollout in Brazil.

CONCLUSIONS

The implementation of PrEP in Brazil is feasible. A synergistic rollout of treatment as prevention and PrEP will maximize public health and individual benefits of the country's comprehensive response to the AIDS epidemic.

Study product adherence measurement in the iPrEx placebo-controlled trial: concordance with drug detection

OBJECTIVE

To evaluate the concordance between adherence estimated by self-report (in-person interview or computer-assisted self-interview), in-clinic pill counts, and pharmacy dispensation records and drug detection among participants in a placebo-controlled pre-exposure prophylaxis HIV prevention trial (iPrEx).

DESIGN

Cross-sectional evaluation of 510 participants who had drug concentration data and matched adherence assessments from their week-24 study visit.

METHODS

Self-reported adherence collected through (1) interview and (2) computer-assisted self-interview surveys, (3) adherence estimated by pill count, and (4) medication possession ratio was contrasted to having a detectable level of drug concentrations [either tenofovir diphosphate (TFV-DP) or emtricitabine triphosphate (FTC-TP)], as well as to having evidence of consistent dosing (tenofovir diphosphate ≥ 16 fmol/10⁶ cells), focusing on positive predictive values, overall and by research site.

RESULTS

Overall, self-report and pharmacy records suggested high rates of product use (over 90% adherence); however, large discrepancies between these measures and drug detection were noted, which varied considerably between sites (positive predictive values from 34% to 62%). Measures of adherence performed generally well in the US sites but had poor accuracy in other research locations. Medication possession ratio outperformed other measures but still had relatively low discrimination.

CONCLUSIONS

The sizable discrepancy between adherence measures and drug detection in certain regions highlights the potential contribution of factors that may have incentivized efforts to seem adherent. Understanding the processes driving adherence reporting in some settings, but not others, is essential for finding effective ways to increase accuracy in measurement of product use and may generalize to promotion efforts for open-label pre-exposure prophylaxis.