Brief Report: Context Matters: PrEP Adherence is Associated With Sexual Behavior Among HIV Serodiscordant Couples in East Africa

Enhanced Oral Pre-exposure Prophylaxis (PrEP) Implementation for Ugandan Fisherfolk: Pilot Intervention Outcomes

Mobile populations such as fisherfolk show high HIV incidence and prevalence. We pilot-tested implementation strategies to enhance pre-exposure prophylaxis (PrEP) uptake and adherence in the context of healthcare outreach events in two mainland fisherfolk communities on Lake Victoria, Uganda from September 2021 to February 2022. The implementation strategies included PrEP adherence supporters (selected from PrEP users' social networks), community workshops (to address misconceptions and stigma, and empower PrEP advocacy), and check-in calls (including refill reminders). PrEP medical records data were collected from 6-months pre-intervention to 6-months post-intervention. Qualitative interviews with 20 PrEP users (10 who continued, 10 who discontinued), 9 adherence supporters, and 7 key partners (providers, community leaders) explored acceptability. Percentages of PrEP initiators (of those eligible) were significantly higher during the intervention (96.5%) than 6-months before the intervention (84.5%), p < 0.0001; percentages of PrEP users who persisted (i.e., possessed a refill) 6-months post-initiation (47.9% vs. 6.7%) and had at least 80% PrEP coverage (based on their medication possession ratio) from the initiation date to 6-months later (35.9% vs. 0%) were higher during versus pre-intervention, p < 0.0001. A comparison fisherfolk community with better healthcare access had lower uptake (78.3%; p < 0.0001) and persistence at 6-months (34.0%; p < 0.001), but higher coverage during the intervention period (70.4%; p < 0.0001). Qualitative data suggested the strategies promoted PrEP use through reduced stigma and misconceptions. The intervention bundle cost was $223.95, $172.98, and $94.66 for each additional person for PrEP initiation, persistence, and coverage, respectively. Enhanced community-based PrEP implementation that fosters a supportive community environment can improve PrEP use in mobile populations without easy access to healthcare. (NCT05084716).

Baseline preferences for oral pre-exposure prophylaxis (PrEP) or dapivirine intravaginal ring for HIV prevention among adolescent girls and young women in South Africa, Uganda and Zimbabwe (MTN-034/IPM-045 study)

INTRODUCTION

Adolescent girls and young women (AGYW) in sub-Saharan Africa are disproportionately affected by the HIV epidemic and face an array of challenges using proven behavioral and biomedical prevention methods. To address the urgent need for expanding prevention options, we evaluated the baseline preferences of HIV prevention methods among participants enrolled in the MTN-034/REACH crossover trial along with their stated product preference prior to product initiation.

METHODS

AGYW aged 16-21 years were enrolled at 4 study sites: Cape Town and Johannesburg, South Africa; Kampala, Uganda; and Harare, Zimbabwe and randomly assigned to the sequence of using oral PrEP and the dapivirine ring for 6 months each, followed by a choice period in which they could choose either product (or neither) for an additional six months. Eligible AGYW were HIV-negative, not pregnant and using effective contraception for at least two months prior to enrollment. Descriptive statistics were used to summarize demographic and behavioral data while multinomial analysis was used to determine predictors of stated product preference (ring or oral PrEP).

RESULTS

Of the 247 AGYW enrolled in REACH, 34% were aged 16-17 and 89% had a primary partner.The median age of sexual debut was 16 years and 40% had ever been pregnant. At screening, 35% of participants were diagnosed with a sexually transmitted infection (STI), 39% had an AUDIT-C score associated with harmful drinking and 11% reported intimate partner violence in the past 6 months. Overall, 28% of participants, had CESD-10 scores suggestive of depressive symptoms (≥12) in the past week. At baseline, similar proportions stated a preference for the ring and oral PrEP (38.1% and 40.5% respectively), with 19% of participants stating they preferred both products equally. Only study site was significantly associated with product preference (P<0.05) with AGYW from Johannesburg having higher odds of preferring the ring and those from Kampala having higher odds of preferring both options equally.

CONCLUSIONS

We successfully enrolled African AGYW with a clear unmet need for HIV prevention. The balanced preference between the two products suggests that multiple biomedical prevention options may be appealing to this age group and could address their prevention needs.

PrEP Use, Sexual Behaviour, and PrEP Adherence Among Men who have Sex with Men Living in Wales Prior to and During the COVID-19 Pandemic

We examined PrEP use, condomless anal sex (CAS), and PrEP adherence among men who have sex with men (MSM) attending sexual health clinics in Wales, UK. In addition, we explored the association between the introduction of measures to control transmission of SARS-CoV-2 on these outcomes. We conducted an ecological momentary assessment study of individuals in receipt of PrEP in Wales. Participants used an electronic medication cap to record PrEP use and completed weekly sexual behaviour surveys. We defined adherence to daily PrEP as the percentage of CAS episodes covered by daily PrEP (preceded by ≥ 3 days of PrEP and followed by ≥ 2 days). Sixty participants were recruited between September 2019 and January 2020. PrEP use data prior to the introduction of control measures were available over 5785 person-days (88%) and following their introduction 7537 person-days (80%). Data on CAS episodes were available for 5559 (85%) and 7354 (78%) person-days prior to and following control measures respectively. Prior to the introduction of control measures, PrEP was taken on 3791/5785 (66%) days, there were CAS episodes on 506/5559 (9%) days, and 207/406 (51%) of CAS episodes were covered by an adequate amount of daily PrEP. The introduction of pandemic-related control measures was associated with a reduction in PrEP use (OR 0.44, 95%CI 0.20–0.95), CAS (OR 0.35, 95%CI 0.17–0.69), and PrEP adherence (RR = 0.55, 95%CI 0.34–0.89) and this may have implications for the health and wellbeing of PrEP users and, in addition to disruption across sexual health services, may contribute to wider threats across the HIV prevention cascade.

Dynamic Perceived HIV Risk and Sexual Behaviors Among Young Women Enrolled in a PrEP Trial in Kenya: A Qualitative Study

Background: In Kenya and elsewhere in sub-Saharan Africa, young women are disproportionately affected by the HIV epidemic compared to young men. The extent to which young women's self-perceptions about risk of HIV acquisition influence their sexual behaviors and use of HIV prevention methods remains unclear. We therefore conducted a qualitative study to explore these issues among young women enrolled in a pre-exposure prophylaxis (PrEP) trial.

Methods: From January 2017 to January 2020, we conducted serial semi-structured in-depth interviews 50 purposively selected young women (18–24 years old) who were participating in the MPYA (Monitoring PrEP for Young Adult women) study—a randomized controlled trial in Thika and Kisumu, Kenya, assessing the impact of SMS reminders on PrEP adherence. Interviews were conducted at three time points (~1 week, 3, and 12 months after initiating PrEP). We used an inductive, content analytic approach to identify key themes related to risk perceptions, sexual behavior, and use of HIV prevention tools.

Results: Around the time of enrollment, most of the 50 women interviewed reported being at high risk of HIV because of their own sexual behaviors, such as inconsistent condom use, multiple sexual partners, and transactional sex. Additionally, high risk perception was based on the behavior of their partners, such as refusing to use condoms and being unsure of their partner's HIV status. Young women's perceived risk of HIV acquisition was a key motivator for PrEP initiation and continuation. During PrEP use, participants reported feeling protected and at less risk compared to peers who were not taking PrEP. Some reported no longer using condoms because they were confident that PrEP provided enough protection. Over time, many young women reported reducing risky sexual behaviors because of the regular counseling and HIV testing they received as part of their PrEP services. This lowered risk perception was in most cases accompanied by discontinuation of PrEP.

Conclusions: HIV risk perception among young women in Kenya was dynamic and influenced their use of PrEP and condoms over time, suggesting an often-deliberate approach to HIV prevention and sexual health.

Initiation, discontinuation, and restarting HIV pre-exposure prophylaxis: ongoing implementation strategies

When used appropriately, pre-exposure prophylaxis (PrEP) substantially reduces the risk of HIV acquisition. Early implementation outcomes often suggest poor PrEP adherence and persistence; however, this intervention is time-limited and the need for PrEP fluctuates as risk behaviours change. In this Viewpoint we examine the current guidelines and early programmatic outcomes after starting, stopping, and restarting PrEP, and we review the implications of PrEP in relation to HIV testing algorithms. Guidelines suggest to discontinue PrEP when a person is no longer at risk for HIV, but effectively implementing this strategy requires support tools to make the decision of stopping and restarting PrEP that considers the complex relationship between risk perceptions and risk behaviours. Safely discontinuing PrEP also requires greater understanding of the daily dosing duration that is needed to protect the person after their last HIV exposure. Additionally, clear strategies are needed to re-engage a person as their HIV exposure risk changes over time.

Sexual Behavior and Perceived HIV Risk Among HIV-Negative Members of Serodiscordant Couples in East Africa

HIV risk perception may influence the use of HIV prevention interventions. Using data from HIV-negative adults enrolled in a study of pre-exposure prophylaxis (PrEP) and antiretroviral therapy for HIV-serodiscordant couples in Kenya and Uganda, we examined associations between: (1) condom use and risk perception and (2) risk perception and PrEP adherence. Two-thirds of HIV-negative partners reported condomless sex with their HIV-positive partner or another partner in the month prior to study enrollment. Compared to those who reported no condomless sex, participants who reported condomless sex during the month prior to study visit had fivefold higher odds of reporting "high risk" vs "no risk" perception (36.3 versus 10.9%: aOR 4.9, 95% CI 3.4-6.9). Reporting condomless sex in the most recent sex act was associated with increased odds of perceiving some HIV risk (aOR for high risk = 7.3, 95% CI 4.9-10.8; aOR for moderate risk = 4.8, 95% CI 3.5-6.7; aOR for low risk = 3.5, 95% CI 2.7-4.6). We found no significant association between risk perception and PrEP adherence. Sexual behavior aligned with perceived HIV risk, which can facilitate an HIV-negative individual's decisions about PrEP use.

Vulnerable Periods: Characterizing Patterns of Sexual Risk and Substance Use During Lapses in Adherence to HIV Pre-exposure Prophylaxis Among Men Who Have Sex With Men

BACKGROUND

Pre-exposure prophylaxis (PrEP) is highly efficacious, but some groups of men who have sex with men may have difficulty adhering to daily dosing. Prevention-effective adherence suggests that PrEP's efficacy depends on adherence at the time of HIV exposure; yet, few studies have examined how exposures (ie, high-risk sex) overlap with periods of consecutive missed PrEP doses. Substance use may also play a role in these vulnerable periods.

METHODS

We used digital pill bottles to monitor the daily adherence of 40 PrEP-experienced patients recruited from an outpatient clinic in the Northeastern US over a six-month period. Participants also completed detailed online diaries every 2 weeks during this time that surveyed their sexual behavior and substance use each day.

RESULTS

Daily adherence was high overall (M = 83.9%, SD = 18.0%), but 53% (N = 21) had a lapse of > 3 consecutive daily PrEP doses over 6 months. Participants' rate of engaging in high-risk condomless anal sex (CAS) did not differ across lapse days versus continuously adherent days. Alcohol use was not associated with engaging in CAS during a PrEP lapse. However, participants reported engaging in CAS significantly more often during a PrEP adherence lapse on days when they also used stimulant drugs.

CONCLUSIONS

Men who have sex with men may have periodic difficulty adhering to PrEP at the specific times when they are at risk. Stimulant drug use could play an important role in increasing HIV risk specifically during adherence lapses.

Assessment of Demographic and Socio-Behavioral Factors on Adherence to HIV Pre-Exposure Prophylaxis Using a Markov Modeling Approach

Purpose: Adherence is important for the effectiveness of human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP). The objective of the current work is to assess the impact of multiple demographic and socio-behavioral factors on the adherence to tenofovir-based PrEP among HIV serodiscordant couples in East Africa using Markov mixed-effects modeling approach.

Methods: The Partners Demonstration Project was a prospective, open-label, implementation science-driven study of HIV PrEP among heterosexual HIV serodiscordant couples in Kenya and Uganda. The uninfected partner received oral PrEP according to the “bridge to antiretroviral therapy [ART]” strategy (i.e., until the infected partner had been on ART for ≥6 months). Adherence was monitored electronically; demographic and socio-behavioral data were collected during study visits. Analyzed data reflect 12 months of follow-up per participant. A two-state, first-order, discrete time Markov model was developed with longitudinal adherence data characterized by “dose taking (1)” and “dose missing (0).” Covariate effects were linearly added in the logit domain of transition probability parameters (P01 and P10) in the model. The full covariate model was initially developed, followed by backward elimination process to reduce the model. All significant covariates reported by a prior primary statistical analysis of the same data were included in the full covariate model.

Results: The model included data from 920 participants, who were predominantly male (65%). Significant covariates associated with higher adherence were 25 years or older [odds ratio (OR) for P10, 0.61], female sex (OR for P10, 0.67), participant wanting the relationship with the partner to succeed (OR for P10, 0.79; OR for P01, 1.45), and sex with partner either with 100% or <100% condom use compared to those reported no sex (OR for P10, 0.84; OR for P01, 1.21). Significant covariates associated with lower adherence were partner on ART >6 months (OR for P01, 0.86; OR for P10, 1.34), subject in the study for >6 months (OR for P01, 0.8; OR for P10, 1.25), and problematic alcohol use (OR for P01, 0.63; OR for P10, 1.16).

Conclusion: The developed Markov model provides a mechanistic understanding of relationship between demographic, socio-behavioral covariates, and PrEP adherence, by indicating the pattern of adherence influenced by each factor over time. Such data can be used for further intervention development to promote PrEP adherence.

Tenofovir Plasma Concentration from Preexposure Prophylaxis at the Time of Potential HIV Exposure: a Population Pharmacokinetic Modeling and Simulation Study Involving Serodiscordant Couples in East Africa

The Partners Demonstration Project was a prospective, open-label, implementation science-driven study of preexposure prophylaxis (PrEP) among heterosexual HIV serodiscordant couples in Kenya and Uganda. Adherence data were collected using the Medication Event Monitoring System (MEMS), and time of sexual activity was collected using the mobile phone short message service (SMS). Two plasma samples were collected at a single study visit. We integrated adherence, pharmacokinetics, and SMS data using a population pharmacokinetic (PopPK) model to simulate tenofovir plasma concentrations from PrEP at the time of sexual activity. In the first stage of this analysis, we used data from the current study to update a prior PopPK model of tenofovir (TFV) developed with data from the Partners PrEP Study (a phase III clinical trial). The second stage involved simulating plasma concentrations at the time of sexual activity using empirical Bayes estimates (EBEs) derived from the final model. In addition, EBEs from a previously published parent metabolite model of TFV (MTN-001, an open-label 3-way crossover study in healthy women) was used to simulate tenofovir diphosphate (TFV-DP) concentrations. We estimated percent PrEP "coverage" as the number of reported sexual events during which simulated concentrations were above an a priori threshold concentrations associated with a high degree of protection from HIV infection: plasma TFV of >40 ng/ml and peripheral blood mononuclear cell (PBMC) TFV-DP concentration of >36 fmol/million cells. The levels of coverage were 72% for TFV and 81% for TFV-DP. These levels are consistent with a high degree of protection against HIV acquisition in this study of a pragmatic delivery model for antiretroviral-based HIV prevention.

HIV-1 self-testing to improve the efficiency of pre-exposure prophylaxis delivery: a randomized trial in Kenya

Background

The introduction of pre-exposure prophylaxis (PrEP) for human immunodeficiency virus-1 (HIV-1) prevention in Africa presents new challenges for health systems that are already overburdened because PrEP delivery requires frequent clinic visits (generally every 3 months) for HIV-1 testing and PrEP refills. HIV-1 self-testing (HIVST) has the potential to improve the efficiency of PrEP delivery by decreasing the number of clinic visits. Here, we describe the rationale and design of a randomized, noninferiority trial designed to test the effectiveness and safety of using HIVST to support PrEP delivery in Kenya.

Methods

The JiPime-JiPrEP (Kiswahili for ‘Test Yourself, PrEP Yourself’) study is a three-arm randomized trial taking place in Thika, Kenya. Participants (n = 495) are eligible for enrollment if they are at least 18 years old, HIV-1 seronegative, and have been taking PrEP for 1 month. Three distinct participant types will be enrolled: men (n = 165) and women (n = 165) who are in mutually disclosed HIV-1 serodiscordant relationships, and women (n = 165) who are at HIV-1 risk and not in a known serodiscordant relationship. Participants in each of these subpopulations will be 1:1:1 randomized to: 1) the standard of care, with quarterly clinic visits; 2) oral HIVST, with biannual clinic visits plus oral HIVSTs to use at the quarters between those visits; or 3) blood-based HIVST, with biannual clinic visits plus blood-based HIVSTs. All participants will complete quantitative surveys and provide blood samples for the objective measurement of PrEP adherence at baseline, 6 months, and 12 months. The primary outcomes are PrEP adherence, PrEP continuation, and HIV-1 testing, measured at 6 months and secondarily at 12 months.

Discussion

The findings from this trial can help to understand how HIVST—a new HIV-1 testing technology—can support health systems in sub-Saharan Africa. Additionally, the findings can inform policy aimed at improving the efficiency of PrEP implementation and scale-up in Kenya.

Trial registration

ClinicalTrials.gov, NCT03593629. Retrospectively registered on 20 July 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3521-2) contains supplementary material, which is available to authorized users.

Actionable Adherence Monitoring: Technological Methods to Monitor and Support Adherence to Antiretroviral Therapy

PURPOSE OF REVIEW

Current digital technologies are being used for "actionable adherence monitoring"; that is, technologies that can be used to identify episodes of non-adherence to ART in a timely manner such that tailored interventions based on adherence data can be provided when and where they are needed most.

RECENT FINDINGS

Current digital communication technologies used to monitor ART adherence include electronic adherence monitors (EAMs), digital ingestion monitors, cellular phones, and electronic pharmacy refill tracking systems. Currently available real-time adherence monitoring approaches based on cellular technology allow for the delivery of interventions precisely when and where they are needed. Such technology can potentially enable significant efficiency of care delivery and impact on adherence and associated clinical outcomes. Standard digital advances, such as automated reminders in EAM and electronic pharmacy records, may also achieve improvements with relatively lower cost and easier implementation. Future research is needed to improve the functionality of these approaches, with attention paid to system-level issues through implementation science, as well as acceptability and ethical considerations at the individual level.

Short Message Service (SMS) Surveys Assessing Pre-exposure Prophylaxis (PrEP) Adherence and Sexual Behavior are Highly Acceptable Among HIV-Uninfected Members of Serodiscordant Couples in East Africa: A Mixed Methods Study

Short message service (SMS) surveys are a promising data collection method and were used to measure sexual behavior and adherence to HIV pre-exposure prophylaxis (PrEP) among HIV-uninfected partners of serodiscordant couples enrolled in a sub-study of the Partners Demonstration Project (an open-label study of integrated antiretroviral therapy and PrEP for HIV prevention in Kenya and Uganda). Questionnaires were completed by 142 participants after study exit. Median age was 29 years; 69% were male. Ninety-five percent (95%) felt SMS surveys were "easy" or "very easy", 74% reported no challenges, and 72% preferred SMS surveys over in-person study visits. Qualitative interviews involving 32 participants confirmed the ease of responding to SMS surveys. Participants also indicated that surveys acted as reminders for adherence to PrEP and condom use and were experienced as support from the study. SMS surveys were generally found to be acceptable in this population and provided real-time context of PrEP use.

A clinic-based tablet application to support safer conception among HIV serodiscordant couples in Kenya: feasibility and acceptability study

BACKGROUND

HIV serodiscordant couples are at heightened risk of HIV transmission when attempting to conceive, yet reproductive goals can outweigh concerns about HIV exposure. Safer conception strategies support fertility desires while minimizing HIV transmission risk and novel mHealth tools can optimize their use. The objective of this analysis is to examine the feasibility and usability of short message service (SMS) messages and a mobile application to support safer conception for HIV serodiscordant couples.

METHODS

We enrolled 74 heterosexual HIV serodiscordant couples with immediate pregnancy desires into a pilot safer conception intervention study in Thika, Kenya. Prior to pregnancy, women received daily 6-item SMS surveys to capture fertility indicators (e.g., menses, basal body temperature) and sexual behavior. The intervention also provided daily oral pre-exposure prophylaxis (PrEP) for the HIV-negative partner and in-depth counseling to accompany publicly-provided antiretroviral therapy (ART) for the HIV-infected partner. Couples attended monthly visits until pregnancy occurred. We measured PrEP use with medication event monitoring system (MEMS) caps and ART use via quarterly viral load quantification. We imported SMS, MEMS, and viral load data into an Android tablet application designed specifically for this setting for couples to view during clinic visits and included predictions of peak fertility days using SMS data. We used descriptive statistics to summarize SMS response data and developed a Google Analytics platform to monitor tablet application usage during follow-up. We also conducted semi-structured interviews with a purposive sample of 5 healthcare providers and 19 couples. Qualitative data were analyzed using a modified constant comparative approach to identify themes related to mHealth intervention feasibility and acceptability.

RESULTS

In our sample, 34 (45.9%) couples had an HIV-infected female partner. The median age of the female partner was 30 years [interquartile range (IQR), 27-35 years], education was 10 years (IQR, 8-12 years), and partnership duration was 3 years (IQR, 2-7 years). Couples were followed for a median of 218 days (IQR, 116-348 days) prior to pregnancy. Participants completed 13,181 of 16,905 (78.0%) SMS surveys surveys sent with a median of 167 completed surveys (IQR, 74-299) per participant. Most participants completed at least 75% of the total SMS messages received (N=58; 77.3%). The tablet application was opened by counselors 1,806 times during the study period (March 2016 through April 2018). In qualitative interviews, the SMS messages were reportedly easy to respond to and "part of the daily routine". Few participants had concerns about message confidentiality. mHealth tools were also found to be acceptable for tracking fertility indicators and enhancing provider-patient communication.

CONCLUSIONS

mHealth strategies are feasible to use and acceptable to support the delivery of safer conception intervention services among HIV serodiscordant couples in Kenya.

A Systematic Evaluation of Effect of Adherence Patterns on the Sample Size and Power of a Clinical Study

The objective of our study was to evaluate the effect of adherence patterns on the sample size and power of a clinical trial. Simulations from a population pharmacokinetic/pharmacodynamic (PK/PD) model linked to an adherence model were used. Four types of drug characteristics, such as long (~35 hours) and short (~12 hours) half-life in combination with earlier or delayed time to reach steady-state PD end points were studied. Adherence patterns were simulated using Markov chains. Our results clearly demonstrate the significant impact of varying levels and patterns of nonadherence on the sample size and power of a study. For drugs with short half-lives the evidence to support efficacy could be diluted by various patterns of nonadherence that would make its efficacy indistinguishable from the response to placebo. Prospectively utilizing clinical trial simulations with thorough incorporation of various adherence patterns would provide valuable information when designing a trial.

Pre-exposure prophylaxis for HIV-negative persons with partners living with HIV: uptake, use, and effectiveness in an open-label demonstration project in East Africa

Background: Pre-exposure prophylaxis (PrEP) can provide high protection against HIV infection and is a recommended intervention for HIV-negative persons with substantial HIV risk.  Demonstration projects conducted in diverse settings worldwide illustrate practical examples of how PrEP can be delivered. This manuscript presents estimates of effectiveness and patterns of PrEP use within a two-year demonstration project of PrEP for HIV-negative members of heterosexual HIV serodiscordant couples in East Africa. Methods: The PrEP delivery model integrated PrEP into HIV treatment services, prioritizing PrEP use for HIV-negative partners within serodiscordant couples before and during the first 6 months after the partner living with HIV initiated antiretroviral therapy (ART).  We measured PrEP uptake through pharmacy records and adherence to PrEP through medication event monitoring system (MEMS) bottle caps and quantification of tenofovir in plasma among a random sample of participants. We estimated HIV infections prevented using a counterfactual cohort simulated from the placebo arm of a previous PrEP clinical trial. Results: We enrolled 1,010 HIV serodiscordant couples that were naïve to ART and PrEP.  Ninety-seven percent of HIV-negative partners initiated PrEP. Objective measures suggest high adherence: 71% of HIV-negative participants took ≥80% of expected doses, as recorded via MEMS, and 81% of plasma samples had tenofovir detected.  Four incident HIV infections were observed (incidence rate=0.24 per 100 person-years), a 95% reduction (95% CI 86-98%, p<0.0001) in HIV incidence, relative to estimated HIV incidence for the population in the absence of PrEP integrated into HIV treatment services.   Conclusions: PrEP uptake and adherence were high and incident HIV was rare in this PrEP demonstration project for African HIV-negative individuals whose partners were known to be living with HIV.  Delivery of PrEP to HIV-negative partners within HIV serodiscordant couples was feasible and should be prioritized for wide-scale implementation.

Pre-exposure prophylaxis for HIV-negative persons with partners living with HIV: uptake, use, and effectiveness in an open-label demonstration project in East Africa

Background: Pre-exposure prophylaxis (PrEP) can provide high protection against HIV infection and is a recommended intervention for HIV-negative persons with substantial HIV risk.  Demonstration projects conducted in diverse settings worldwide illustrate practical examples of how PrEP can be delivered. This manuscript presents estimates of effectiveness and patterns of PrEP use within a two-year demonstration project of PrEP for HIV-negative members of heterosexual HIV serodiscordant couples in East Africa. Methods: The PrEP delivery model integrated PrEP into HIV treatment services, prioritizing PrEP use for HIV-negative partners within serodiscordant couples before and during the first 6 months after the partner living with HIV initiated antiretroviral therapy (ART).  We measured PrEP uptake through pharmacy records and adherence to PrEP through medication event monitoring system (MEMS) bottle caps and quantification of tenofovir in plasma among a random sample of participants. We estimated HIV infections prevented using a counterfactual cohort simulated from the placebo arm of a previous PrEP clinical trial. Results: We enrolled 1,010 HIV serodiscordant couples that were naïve to ART and PrEP.  Ninety-seven percent of HIV-negative partners initiated PrEP. Objective measures suggest high adherence: 71% of HIV-negative participants took ≥80% of expected doses, as recorded via MEMS, and 81% of plasma samples had tenofovir detected.  Four incident HIV infections were observed (incidence rate=0.24 per 100 person-years), a 95% reduction (95% CI 86-98%, p<0.0001) in HIV incidence, relative to estimated HIV incidence for the population in the absence of PrEP integrated into HIV treatment services.   Conclusions: PrEP uptake and adherence were high and incident HIV was rare in this PrEP demonstration project for African HIV-negative individuals whose partners were known to be living with HIV.  Delivery of PrEP to HIV-negative partners within HIV serodiscordant couples was feasible and should be prioritized for wide-scale implementation.