Ingestible sensor system for measuring, monitoring and enhancing adherence to antiretroviral therapy: An open-label, usual care-controlled, randomised trial

BACKGROUND

Co-encapsulated antiretrovirals (ARVs) with ingestible sensor (IS) has the capacity to monitor adherence in real-time using a sensor patch, a mobile device, and supporting software. We evaluated the acceptability, effectiveness, and sustainability of the IS system with real-time text reminders.

METHODS

Participants were recruited from HIV clinics in Los Angeles and were randomised 1:1 to IS or usual care (UC) group. Adherence to ARVs (primary outcome) was measured by IS system (IS group only), plasma ARV concentration, and self-report. IS-measured adherence was clustered by group-based trajectory model and was validated by ARV concentration summarized by integrated pharmacokinetic adherence measure (IPAM) score. HIV RNA viral load (VL) was compared between IS and UC group.

FINDINGS

A total of 112 (IS = 54, UC = 58) participants who completed baseline with at least one follow-up data collection were included in analyses. Overall satisfaction rate for the IS system was >90%. The IPAM score was higher (0.018, 95% CI: -0.098-0.134, p = 0.75) and VL decayed faster (-0.020, 95% CI: -0.042-0.002, p = 0.08) in the IS group compared with the UC group. The ingestible sensor system was well tolerated by study participants.

INTERPRETATION

The IS system was well accepted by participants and its use was associated with improved adherence and lower HIV RNA VL. The findings provide a potentially effective strategy for improving adherence.

FUNDING

This work was supported by grant R01-MH110056 from the National Institute of Mental Health (NIMH)/National Institutes of Health (NIH). Y. Wang was in part supported by the NIMH/NIH award T32MH080634. E. Daar was in part supported by the National Center for Advancing Translational Sciences through UCLACTSI Grant UL1TR001881. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

Low incidence and prevalence of hepatitis C in two cohorts of HIV pre-exposure prophylaxis adherence interventions in men who have sex with men in Southern California

HIV pre-exposure prophylaxis (PrEP) has been associated with incident hepatitis C virus (HCV) infection in men who have sex with men (MSM) due to decreased condom use. We examined rates of HCV among MSM and transgender women at high-risk of HIV on PrEP in Southern California using data from two trials (NCT01761643 and NCT01781806). Five of 599 participants (0.84%, 95% CI, 0.27-1.93) had HCV antibodies detected at entry. Factors associated with HCV seropositivity included being older (p = .002) and lower education level (p < .001). HCV-positive participants had no reported cases of sexually transmitted infection (rectal, urethral or pharyngeal gonorrhoea and/or chlamydia) at entry while HCV-negative participants had a prevalence of 18% (95% CI, 15%-21%). There were no significant differences in substance use and sexual risk behaviour between HCV-positive and HCV-negative participants 1-3 months prior to entry. Among early PrEP adopters, incident HCV did not occur despite ongoing condomless intercourse. Screening intervals for HCV in MSM on PrEP should be led by a risk behaviour assessment.

Sexually transmitted infections among participants in an HIV PrEP adherence trial

BACKGROUND

HIV PrEP effectiveness is highly dependent on adherence. High STI incidence has been reported among PrEP users. We assessed the relationship between STI incidence (CT, NG, and syphilis) and PrEP adherence.

METHODS

We performed a subanalysis of a controlled, open-label, two-arm, randomized clinical demonstration project of a text-message based adherence intervention. Participants had 48 weeks of follow-up and had STI testing every 12 or 24 weeks. PrEP adherence was measured at week 48 using intracellular tenofovir-diphosphate drug concentrations. We calculated incidence rate ratios for STIs among those adherent as compared with those not adherent to PrEP.

RESULTS

Of the 381 assessed for CT, NG and syphilis at one or more follow-up visits, there were 16 cases of syphilis or 5.0 per 100 person years (95% CI: 2.6, 7.5); 63 cases of NG or 26.3 per 100 person years (95% CI: 19.8, 32.8); and 81 cases of CT or 36.3 per 100 person years (95% CI: 28.4, 44.2). We found no association between adequate PrEP adherence and STI incidence (aIRR: 0.97 95% CI: 0.67, 1.40).

CONCLUSIONS

We found that the incidence of STIs was not significantly different between those adherent to PrEP and those non-adherent. Further research is needed to assess how PrEP use may impact STIs over time.

Pre-Exposure Prophylaxis Perspectives, Sociodemographic Characteristics, and HIV Risk Profiles of Cisgender Women Seeking and Initiating PrEP in a US Demonstration Project

Little information is known about the cisgender women who seek and initiate pre-exposure prophylaxis (PrEP) for HIV prevention in the United States. Adherence Enhancement Guided by Individualized Texting and Drug Levels was a 48-week single-arm open-label demonstration study of daily oral tenofovir disoproxil fumaratel emtricitabine (TDF/FTC) in cisgender women ≥ 18 years old at risk for HIV. Participants were surveyed at screening and enrollment about sociodemographics, HIV risk perception and behaviors, and PrEP perspectives and aggregated into three risk groups according to HIV sexual risk behavior: being in a serodiscordant partnership (SD), engaging in sex work (SW), and having partners with unknown HIV status at risk for HIV (UP). One hundred sixty-seven women presented for screening with n = 31 screen failures. Of the 162 women completing enrollment, mean age was 40 (standard deviation 11), with 41% non-Hispanic Black, 22% non-Hispanic White, and 19% Latina. Compared with those who screened ineligible, enrolled participants were more likely to have heard of PrEP, had higher HIV risk perception, and reported higher perceived PrEP efficacy. Sixty-four women (47%) were categorized as SD, 21 (15%) as SW, and 51 (38%) as UP. The SW were more likely to report higher levels of drinking and drug use (p = 0.002) and history of intimate partner violence in the past year (p < 0.001) compared with SD and UP. Among cisgender women enrolled, there were significant differences between the three risk groups by demographics, HIV risk behavior, and PrEP perspectives, suggesting that interventions to successfully implement PrEP in US women may need to be tailored by HIV risk group. Clinical Trial Registration number: NCT02584140.

Results from a PrEP Demonstration Project for At-Risk Cisgender Women in the United States

BACKGROUND

Daily oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) is effective for reducing HIV acquisition among cisgender women. We report results from the first United States observational open-label demonstration project of PrEP among at-risk cisgender women.

METHODS

Adherence Enhancement Guided by Individualized Texting and Drug Levels (AEGiS) was a 48-week single-arm open-label demonstration study of daily oral TDF/FTC in cisgender women ≥18 years old at-risk for HIV. Adherence was supported using two-way text messaging and titrated adherence counseling based on rapid-turnaround tenofovir diphosphate concentrations from dried blood spots. Study visits occurred at baseline, and at weeks 4, 12, and quarterly through week 48. Outcomes included TDF/FTC adherence, retention and persistence.

RESULTS

From June 2016 to October 2018, 136 cisgender women enrolled [mean age 40 (SD 11); 38% non-Hispanic (NH) Black and 19% Latina]. At 48 weeks, 84 (62%) participants were retained and 62 (46%) remained on PrEP. Over one-third (12/31) of those on study but off PrEP throughout study discontinued TDF/FTC due to side effects, and one adverse event led to study discontinuation. Of 120 participants with drug concentrations measured, 67 (56%) had at least one concentration consistent with ≥6 doses/week (d/w); 22 (18%) had consistent ≥6 d/w across all study visits attended. There were no incident HIV infections and 4 incident bacterial STIs.

CONCLUSION

Adequate PrEP adherence for protective drug concentrations was not achieved for most study participants. More work needs to be done to fully explicate the reasons for non-adherence and low retention in cisgender women.

997. The Purview Paradox: PrEP Utilization at a Major Southern California County Teaching Hospital and Affiliated Clinics

Background

According to the Centers for Disease Control (CDC), PrEP coverage in the United States was approximately 18% in 2018 and 21.9% in California. We predict that PrEP prescription is lower at Harbor-UCLA Medical Center (HUMC) and affiliated clinics within Los Angeles County Department of Health Services.

Methods

A retrospective chart review of HIV-negative patients with ICD-10 coded diagnoses of sexually transmitted infections (STIs) or high-risk sexual behavior was performed across various medical specialties at HUMC and affiliated clinics in 2018. Documentation of sexual behavior risk reduction counseling, PrEP discussion and prescription was reviewed from electronic medical records for each encounter. Descriptive statistics and analysis were completed in STATA Version 16.1, StataCorp LLC.

Results

The sample included 250 individual patients, all with indications for PrEP. Of those, 47.2% identified as Latinx and 27.2% Black. Table 1 shows 74% of patients identified as heterosexual whereas 9.2% identified as gay, and 4.4% bisexual. Of the 250 individual patients, 87 (34.8%) returned for a 2nd visit, 35 (14.0%) for a third, and 9 (3.6%) for a 4th visit, for a total of 381 encounters. Of the total encounters, 49.3% had sexual behavior risk reduction counseling, 7.3% had discussions about PrEP with their provider, and only 2.1% were newly prescribed PrEP (Table 2). Of the 2.1% new PrEP prescriptions, 1.8% were prescribed by family medicine providers with no new prescriptions by OB/GYN or acute care providers. Only 25% of new PrEP prescriptions were female patients. A positive test for an STI occurred in 45.1% of total encounters while high risk sexual behavior was identified in 54.9% of encounters (Table 3).

Table 1: First Encounter Demographics (N=250 Individual Patients)

Table 2: Primary Outcomes by Specialty (N=381 Total Encounters)

Table 3: Sexually Transmitted Infections Frequency (N=381 Total Encounters)

Conclusion

Our findings demonstrate that the percent of individuals newly prescribed PrEP (2.1%) at HUMC and affiliated clinics is less than that reported nationally and in California. This suggests that municipal health systems fall short in PrEP usage, notably for structurally vulnerable populations such as racial minorities as well as heterosexual females. Ending racial/ethnic disparities in HIV and in PrEP coverage not only requires educating specialty providers on PrEP, but also addressing structural racism and identifying structural barriers to care in vulnerable communities.

Disclosures

All Authors: No reported disclosures

Greater Levels of Self-Reported Adherence to Pre-Exposure Prophylaxis (PrEP) are Associated with Increased Condomless Sex Among Men Who Have Sex with Men

The effectiveness of pre-exposure prophylaxis (PrEP) against HIV acquisition depends on treatment adherence; however, within-person associations between levels of PrEP adherence and engagement in condomless sex have not been well studied. In the context of a demonstration project, 372 men who have sex with men received once-daily PrEP and completed six study visits over 48 weeks. Two-part growth mixture modeling was used to examine the longitudinal trajectory of condomless anal intercourse (CAI) and self-reports of PrEP adherence, controlling for relevant covariates. Over time, greater PrEP adherence was contemporaneously associated with both a higher likelihood of engaging in any CAI and with a greater number of CAI acts. Substance use was also associated with a higher likelihood of engaging in CAI. Contemporaneous associations between self-reported PrEP adherence and CAI suggest that adherence behaviors may be motivated by the desire to mitigate risk of HIV infection; however, exact directionality is unknown.

Real-Time and Wireless Assessment of Adherence to Antiretroviral Therapy With Co-Encapsulated Ingestion Sensor in HIV-Infected Patients: A Pilot Study

Adherence with antiretroviral therapy is important for preventing disease progression and HIV transmission. The co-encapsulated pill sensor system sends a signal through a cutaneous patch and allows real-time monitoring of pill ingestion. A 16-week pilot study used a sensor system in 15 HIV-infected individuals with real-time monitoring of pill-taking with a personalized short message system text. System acceptability was assessed by survey at weeks 4, 8, 12, and 16. Follow-up occurred in 80% of subjects through 8 weeks. The system effectively collected measures of pill ingestion, which triggered text message reminders. Only 2 of 14 participants stated that co-encapsulated pills were "unable to take" or "poorly tolerated." At least 75% of respondents stated at each visit that the patch was very or somewhat comfortable. With regard to text message reminders, only 10-15% of the participants at any visit did not find the messages to be helpful. Larger studies will define the utility of this system to assess antiretroviral adherence relative to standard measures.

Characteristics of a cohort of high-risk men who have sex with men on pre-exposure prophylaxis reporting transgender sexual partners

Transgender people continue to be at high-risk for HIV acquisition, but little is known about the characteristics of their sexual partners. To address this gap, we examined sociodemographic and sexual characteristics of cisgender men who have sex with men (MSM) on pre-exposure prophylaxis (PrEP) reporting transgender sexual partners.A cohort of 392 MSM in southern California in a randomized clinical trial for PrEP adherence were followed from 2013 to 2016. Multivariable generalized estimating equation and logistic models identified characteristics of MSM reporting transgender sexual partners and PrEP adherence.Only 14 (4%) MSM reported having transgender sexual partners. MSM were more likely to report transgender partners if they were African American, had incident chlamydia, reported injection drug-using sexual partners, or received items for sex. Most associations remained significant in the multivariable model: African American (adjusted odds ratio [AOR] 11.20, P = .01), incident chlamydia (AOR 3.71, P = .04), and receiving items for sex (AOR 5.29, P = .04). There were no significant differences in PrEP adherence between MSM reporting transgender partners and their counterpart.MSM who report transgender sexual partners share characteristics associated with individuals with high HIV prevalence. Identifying this group distinct from larger cohorts of MSM could offer new HIV prevention opportunities for this group of MSM and the transgender community.

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.

Trajectories and Predictors of Longitudinal Preexposure Prophylaxis Adherence Among Men Who Have Sex With Men

Background

Adherence is necessary for efficacy of preexposure prophylaxis (PrEP), and text-messaging methods are promising tools for both adherence assessment and support. Although PrEP adherence is variable, little research has examined patterns of variability or factors associated with longitudinal use.

Methods

In the context of a randomized controlled trial of text-messaging versus standard of care for PrEP adherence, 181 men who have sex with men received once-daily tenofovir disoproxil fumarate/emtricitabine and daily adherence texts for 48 weeks. Growth mixture modeling (GMM) was used to identify subgroups of individuals with similar trajectories of text-reported adherence. Between-group differences in pharmacologic measures of adherence (ie, tenofovir diphosphate and emtricitabine triphosphate levels), as well as predictors and study-end attitudes associated with group membership, were examined.

Results

GMM identified 4 trajectories of text-reported adherence. Classes with higher text-reported adherence had higher drug concentrations. Younger age and minority race were associated with lower adherence, and individuals in classes with lower adherence had greater baseline levels of depression, substance use concerns, and sexual risk. Differences in study satisfaction were also associated with adherence.

Conclusions

This study supports the use of text-reported PrEP adherence. Identifying factors associated with less-than-optimal adherence may aid clinicians in anticipating at-risk patients requiring augmented intervention.

Clinical trials registration

NCT01761643.

Effect of Vitamin D Supplementation on Bone Turnover Markers During HIV Pre-Exposure Prophylaxis Using Tenofovir Disoproxil Fumarate-Emtricitabine in Men Who Have Sex with Men

Pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) reduces bone mineral density in HIV-uninfected men who have sex with men (MSM). We hypothesized that PrEP with TDF-FTC would increase bone turnover markers (BTMs) at week 24 and that vitamin D supplementation from weeks 24 to 48 would blunt this increase. Participants were from a cohort of 398 MSM and transgender women who received daily TDF-FTC for PrEP. At week 24, a prospective intervention group initiated vitamin D3 4,000 IU daily. Concurrent controls were selected from the cohort who took ≤400 IU/day of vitamin D3 matched by age, race, and body mass index. The primary endpoint was the change in procollagen-I N-terminal propeptide (P1NP) from weeks 24 to 48. Paired t-tests were used to compare changes in BTMs between intervention and controls. Among 48 intervention-control pairs, median age was 33 years. At baseline, 68.9% of the intervention group and 77.3% of controls were vitamin D sufficient (≥20 ng/mL, p = .94). P1NP, C-telopeptide, parathyroid hormone (PTH), and 25-OH vitamin D3 did not increase significantly at week 24. P1NP fell by a mean ± SD of -27.6 ± 49.9 pg/mL from weeks 24 to 48 with vitamin D and -2.5 ± 40.2 pg/mL in controls (p = .01). There were no significant between-group differences in the weeks 24-48 change in C-telopeptide, PTH, or 25-OH vitamin D3. Vitamin D3 supplementation with 4,000 IU/day resulted in a significant reduction in the BTM P1NP compared with controls, suggesting that this intervention has potential to improve bone health during PrEP.

Substance Use and Adherence to HIV Preexposure Prophylaxis for Men Who Have Sex with Men1

Substance and alcohol use were not associated with decreased adherence.

The effectiveness of oral HIV preexposure prophylaxis (PrEP) strongly depends on maintaining adherence. We investigated the association between substance use and PrEP adherence, as well as incident sexually transmitted infections (STIs) in a high-risk cohort of 394 participants (391 men who have sex with men and 3 transgender women) who were enrolled in a PrEP demonstration project. We assessed baseline and ongoing substance use over a 48-week period for stimulants and nonstimulant substances and for each substance separately. We measured PrEP adherence by using dried blood spots to obtain levels of tenofovir diphosphate. No differences in these levels were found between substance users and nonsubstance users. Baseline stimulant use was strongly associated (odds ratio 3.4; p<0.001) with incident STIs during the study. Thus, PrEP adherence was not decreased by substance use. Because substance users had increased rates of STIs, indicating higher-risk behavior, they might be excellent candidates for PrEP.

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

BACKGROUND

Efficacy of HIV pre-exposure prophylaxis (PrEP) among men who have sex with men is well documented in randomized trials. After trial completion, participants are challenged with acquiring PrEP on their own and remaining adherent.

METHODS

This was a follow-up study of the TAPIR randomized controlled multicenter PrEP trial. Participants were contacted after their last TAPIR visit (ie, after study-provided PrEP was discontinued) to attend observational posttrial visits 24 and 48 weeks later. Adherence during TAPIR and posttrial visits was estimated by dried blood spot intracellular tenofovir diphosphate levels (adequate adherence defined as tenofovir diphosphate levels >719 fmol/punch). Binary logistic regression analysis assessed predictors of completing posttrial visits and PrEP adherence among participants completing ≥1 visit.

RESULTS

Of 395 TAPIR participants who were on PrEP as part of the TAPIR trial for a median of 597 days (range 3-757 days), 122 (31%) completed ≥1 posttrial visit (57% of University of California San Diego participants completed posttrial visits, whereas this was 13% or lower for other study sites). Among participants who completed ≥1 posttrial visit, 57% had adequate adherence posttrial. Significant predictors of adequate adherence posttrial were less problematic substance use, higher risk behavior, and adequate adherence in year 1 of TAPIR.

CONCLUSION

More than half of PrEP users followed after trial completion had successfully acquired PrEP and showed adequate adherence. Additional adherence monitoring and intervention measures may be needed for those with low PrEP adherence and problematic substance use during the first year of trial.

Recent HIV Risk Behavior and Partnership Type Predict HIV Pre-Exposure Prophylaxis Adherence in Men Who Have Sex with Men

Men who have sex with men (MSM) reporting higher HIV risk behavior over time are often more adherent to pre-exposure prophylaxis (PrEP), but it is unclear if recent risk behavior and partnership type affect long-term PrEP adherence. HIV-negative MSM and transgender women completing the 48-week randomized study TAPIR (Daily Text Messages to Support Adherence to PrEP in At-Risk for HIV Individuals) were included. At baseline and weeks 24 and 48, a modified Calculated Risk (mCalcR) Score estimated the likelihood of HIV seroconversion over 1 year based on reported condomless anal sex acts in the last month and current sexually transmitted infection. mCalcR scores were categorized as low, moderate, and high/very high risk. Partnership type was classified as no partner/single HIV-negative partner (no/single-), single HIV-positive partner (single+), or multiple partners of any serostatus (multi) in the past 3 months. PrEP adherence was measured by intracellular tenofovir-diphosphate (TFV-DP) levels. Among 313 individuals, there was no difference in mCalcR category from baseline to week 48. There was a significant change in partnership type, with no/single partnerships increasing from 0.5% to 9%. Participants with moderate and high/very risk had higher TFV-DP levels than the low-risk group. No/single participants had lower TFV-DP levels than those reporting single+ or multi. Although there was a shift toward lower-risk partnerships, HIV risk category remained stable over time. Individuals with riskier behaviors and partnerships had higher PrEP drug levels, suggesting continued motivation for and adherence to PrEP.

Sexual Risk Compensation in a Pre-exposure Prophylaxis Demonstration Study Among Individuals at Risk of HIV

BACKGROUND

A public health concern regarding HIV pre-exposure prophylaxis (PrEP) is sexual risk compensation (ie, increased unsafe sex among PrEP users that may undermine prevention efforts).

METHODS

This demonstration study (NCT#01761643; initiated in 2013) included 398 men who have sex with men who initiated PrEP and were followed over 48 weeks at 4 sites in Southern California. Wilcoxon signed-rank tests compared previous 30-day number of sex partners and condomless insertive anal sex and receptive anal sex (CIAS and CRAS, respectively) acts at weeks 4, 12, 24, 36, and 48 to baseline. At 2 sites, PrEP users were also compared with a lagged, comparison group of 99 men who have sex with men who did not receive PrEP over 24 weeks using linear regression models, adjusting for age, race/ethnicity, education, and respective baseline scores. Logistic regression compared week 24 sexually transmitted infection (STI) rates.

RESULTS

Over 48 weeks in the PrEP group, there were significant decreases in the number of unknown HIV status sex partners and increases in CRAS at all study visits; there was no consistent change in number of HIV+ sex partners or CIAS. Among participants at 2 sites, there were no significant differences between PrEP and non-PrEP users in change in number of partners, CIAS, CRAS, or STI rates at week 24.

CONCLUSIONS

Among early adopters of PrEP, there is some evidence for sexual risk compensation. Results support current guidelines of regular STI screening and behavioral risk reduction and adherence counseling with the provision of PrEP.

Randomized Trial of a Health Coaching Intervention to Enhance Retention in Care: California Collaborative Treatment Group 594

Poor linkage, engagement and retention remain significant barriers in achieving HIV treatment goals in the US. HIV-infected persons entering or re-entering care across three Southern California academic HIV clinics, were randomized (1:1) to an Active, Linkage, Engagement, Retention and Treatment (ALERT) specialist for outreach and health coaching, or standard of care (SOC). The primary outcome of time to loss to follow up (LTFU) was compared using Cox proportional hazards regression modeling. No differences in the median time to LTFU (81.7 for ALERT versus 93.6 weeks for SOC; HR 1.27; p = 0.40), or time to ART initiation was observed (N = 116). Although, ALERT participants demonstrated worsening depressive symptomatology from baseline to week 48 compared to SOC (p = 0.02). The ALERT intervention did not improve engagement and retention in HIV care over SOC. Further studies are needed to determine how best to apply resources to improve retention and engagement.

Effect of rectal douching/enema on rectal gonorrhoea and chlamydia among a cohort of men who have sex with men on HIV pre-exposure prophylaxis

OBJECTIVES

Rectal douching/enema (RD) is a common practice among men who have sex with men (MSM) in preparation for sex. RD can break down the rectal mucosal barrier and potentially affect the rectal microbiome. The objective of this study was to understand if RD is associated with acquiring rectal infections (RI) with rectal gonorrhoea (NG) and/or chlamydia (CT).

METHODS

From 2013 to 2015, 395 adult HIV-uninfected MSM were enrolled in a randomised controlled study for pre-exposure prophylaxis (PrEP) adherence with routine sexual risk survey and testing. Using data from this cohort, baseline differences by RI were assessed using Pearson's χ² and Wilcoxon-Mann-Whitney test. Association between RD and RI was modelled using multivariable logistic regression adjusted for potential confounders (sexual behaviour, substance use and age) selected a priori. Effect modification by number of male partners and sensitivity analysis to rule out reverse causality were also conducted.

RESULTS

Of 395 participants, 261 (66%) performed RD and 133 (33%) had at least one NG/CT RI over 48 weeks. Number of condomless anal receptive sex (med: 4, p<0.001), male partners (med:6, p<0.001) and substance use (any of methamphetamine/hallucinogens/dissociative/poppers) (p<0.001) were associated with increased odds of RI. Controlling for potential confounders, odds of prevalent RI were 3.59 (p<0.001, 95% CI 1.90 to 6.78) and incident RI 3.87 (p=0.001, 95% CI 1.78 to 8.39) when douching weekly or more compared with not douching. MSM with more than six male partners had 5.34 (p=0.002, 95% CI 1.87 to 15.31) increased odds of RI when douching weekly or more compared with not douching.

CONCLUSION

Rectal hygiene with RD is a common practice (66%) among HIV-uninfected MSM on PrEP in this study, which increases the odds of acquiring rectal NG and/or CT independent of sexual risk behaviour, substance use and other factors. This suggests interventional approaches targeting rectal hygiene products and practices could reduce sexually transmitted infections.

Recent HIV Risk Behavior and Partnership Type Predict PrEP Adherence in Men Who Have Sex with Men

Background

Individuals engaging in higher risk behavior are often more adherent to PrEP but it is unclear if partnership type itself affects PrEP adherence. We examined the effect of recent HIV risk behaviors and partnership type on PrEP adherence in men who have sex with men (MSM) taking PrEP.

Methods

CCTG 595 is a 48-week PrEP demonstration study of 398 HIV− at-risk MSM. At baseline and week 48, HIV risk score was estimated as the probability of seroconversion over the next year based on number of condomless anal sex acts with HIV+/unknown partners in the last month and any STI diagnosed at study visit. HIV risk score was categorized as low (<0.12), moderate (0.12−0.59) and high (>0.59) risk based on population seroconversion probabilities. Partnership type was assigned as no/single HIV− partner, single HIV+ partner, or multiple partners of any serostatus in the past 3 months. PrEP adherence was estimated by intracellular tenofovir-diphosphate (TFV-DP) levels as a continuous variable at week 48. Statistical methods included McNemar’s test, Wilcoxon rank-sum test, and linear regression model where appropriate.

Results

Of 313 MSM who completed week 48, there was no significant change in HIV risk category from baseline to week 48 (low: 44 to 42%; moderate: 27 to 24%; high: 28 to 34%; P = 0.25). There was a significant change in partnership type, with the proportion of those with no or single HIV− partnerships increasing (1 to 9%, P < 0.001). In univariate analysis, moderate and high-risk groups had higher TFV-DP levels than the low-risk group at week 48 (P = 0.018). Participants with no/single HIV− partner had significantly lower TFV-DP levels than those with one HIV+ partner or multiple partners (P = 0.007). In a multivariable linear regression model, only low-risk partnerships remained significant where no/single HIV− partnerships were associated with lower TFV-DP levels (mean difference = −344fmol/punch [−617, −71], P = 0.014).

Conclusion

Although there was a shift in partnership type towards lower risk partnerships, objective HIV risk behavior remained stable over time. Individuals with higher HIV risk behaviors and risk partnerships had higher TFV-DP levels suggesting maintained strong motivation for PrEP adherence. Thus, recent sexual risk behavior and partnership type may be important predictors of PrEP adherence in MSM.

Disclosures

All authors: No reported disclosures.

Effect of Rectal Hygiene on Sexually Transmitted Infections Among HIV-Negative Men Who Have Sex with Men (MSM)

Background

Rectal gonorrhea (NG) and chlamydia (Connecticut) infections are common among men who have sex with men (MSM). Rectal douching/enema (RDE) is a common practice among MSM that can affect the rectal microbiome. It is unclear if this practice is associated with acquiring rectal infections (RI) with either NG or CT.

Methods

From 2013–2015, 398 adult HIV-negative MSM and transwomen were enrolled in a randomized controlled study on text messaging for adherence to pre-exposure prophylaxis (PrEP). Participants were surveyed on sexual behavior, frequency of RDE, drug use, and nutritional habits in conjunction with routine sexually transmitted infection testing. Pearson’s χ ² and two sample t-tests were used to measure significance of RDE and other risk factors with RI. Multivariable logistic regression model was used to control for confounding and assess the association of RDE with RIs. Confounders (i.e., age, number anal receptive sex, number sex partners) were selected a priori for inclusion in the final model based on a causal model and statistical significance.

Results

Of 397 participants, 262 (67%) performed RDE and 132 (33%) had at least one NG or CT rectal infection over 48 weeks. Number of condomless anal receptive sex acts (mean = 19, P < 0.001), condom use for anal receptive sex (P = 0.017), number of male sex partners in past 3 months (mean = 14, P = 0.001), and the use of poppers (P < 0.001) were associated with RI. There was no significant association between nutritional habits, probiotic foods or supplements and RI, with the exception of energy bars (P = 0.029). Controlling for confounders, RI was associated with RDE less than weekly with OR = 1.02 (95% CI 0.52–1.99) while RDE weekly or more had OR = 2.08 (95% CI 1.03–4.17). Stratified by number of partners, MSMs with more than the median (>6) number of partners had OR = 4.96 (95% CI 1.29–19.03) if performing RDE less than weekly, and OR = 6.03 (95% CI 1.55–23.49) if weekly or more.

Conclusion

Rectal hygiene with douching/enemas is a common practice among MSMs on PrEP, which increases the odds of acquiring rectal NG and/or CT. This finding is suggestive for the use of rectal hygiene products/practices as potential targets for sexually transmitted infection prevention.

Disclosures

All authors: No reported disclosures.

Frame me if you must: PrEP framing and the impact on adherence to HIV Pre-exposure Prophylaxis

Background

“PrEP whore” has been used both as a pejorative by PrEP opponents in the gay community and, reactively, by PrEP advocates as a method to reclaim the label from stigmatization and “slut-shaming.” The actual prevalence and impact of such PrEP-directed stigma on adherence have been insufficiently studied.

Methods

CCTG 595 was a randomized controlled PrEP demonstration project in 398 HIV-uninfected MSM and transwomen. Intracellular tenofovir-diphosphate (TFV-DP) levels at weeks 12 and 48 were used as a continuous measure of adherence. At study visits, participants were asked to describe how they perceived others’ reactions to them being on PrEP. These perceptions were categorized a priori as either “positively framed,” “negatively framed,” or both. We used Wilcoxon rank-sum to determine the association between positive and negative framing and TFV-DP levels at weeks 12 and 48.

Results

By week 4, 29% of participants reported perceiving positive reactions from members of their social groups, 5% negative, and 6% both. Reporting decreased over 48 weeks, but positive reactions were consistently reported more than negative. At week 12, no differences in mean TFV-DP levels were observed in participants with positively-framed reactions compared with those reporting no outcome or only negatively-framed (1338 [IQR, 1036-1609] vs. 1281 [946-1489] fmol/punch, P = 0.17). Additionally, no differences were observed in those with negative reactions vs. those without (1209 [977–1427] vs. 1303 [964–1545], P = 0.58). At week 48, mean TFV-DP levels trended toward being higher among those that report any reaction, regardless if positive (1335 [909–1665] vs. 1179 [841–1455], P = 0.09) or negative (1377 [1054–1603] vs. 1192 [838–1486], P = 0.10) than those reporting no reaction. At week 48, 46% of participants reported experiencing some form of PrEP-directed judgment, 23% reported being called “PrEP whore,” and 21% avoiding disclosing PrEP use.

Conclusion

Over 48 weeks, nearly half of participants reported some form of judgment or stigmatization as a consequence of PrEP use. However, individuals more frequently perceived positively framed reactions to being on PrEP than negative. Importantly, long-term PrEP adherence does not appear to suffer as a result of negative PrEP framing.

Disclosures

All authors: No reported disclosures.