Assessment of PrEP eligibility and uptake among at-risk MSM participating in a HIV-1 vaccine feasibility cohort in coastal Kenya

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.

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.

Peer Mobilization and Human Immunodeficiency Virus (HIV) Partner Notification Services Among Gay, Bisexual, and Other Men Who Have Sex With Men and Transgender Women in Coastal Kenya Identified a High Number of Undiagnosed HIV Infections

Background

Human immunodeficiency virus (HIV) partner notification services (HPN), peer mobilization with HIV self-testing, and acute and early HIV infection (AEHI) screening among gay, bisexual, and other men who have sex with men (GBMSM) and transgender women (TGW) were assessed for acceptability, feasibility, and linkage to antiretroviral therapy (ART) and preexposure prophylaxis (PrEP) services.

Methods

Between April and August 2019, peer mobilizers mobilized clients by offering HIV oral self-tests and immediate clinic referral for clients with AEHI symptoms. Mobilized participants received clinic-based rapid antibody testing and point-of-care HIV RNA testing. Newly diagnosed participants including those derived from HIV testing services were offered immediate ART and HPN. Partners were recruited through HPN.

Results

Of 772 mobilized clients, 452 (58.5%) enrolled in the study as mobilized participants. Of these, 16 (3.5%) were HIV newly diagnosed, including 2 (0.4%) with AEHI. All but 2 (14/16 [87.5%]) initiated ART. Thirty-five GBMSM and TGW were offered HPN and 27 (77.1%) accepted it. Provider referral identified a higher proportion of partners tested (39/64 [60.9%] vs 5/14 [35.7%]) and partners with HIV (27/39 [69.2%] vs 2/5 [40.0%]) than index referral. Of 44 enrolled partners, 10 (22.7%) were newly diagnosed, including 3 (6.8%) with AEHI. All 10 (100%) initiated ART. PrEP was initiated among 24.0% (103/429) mobilized participants and 28.6% (4/14) partners without HIV.

Conclusions

HPN, combined with a peer mobilization-led self-testing strategy and AEHI screening for GBMSM and TGW, appears to be acceptable and feasible. These strategies, especially HPN provider referral, effectively identified undiagnosed HIV infections and linked individuals to ART and PrEP services.

Risk factors for loss to follow-up among at-risk HIV negative men who have sex with men participating in a research cohort with access to pre-exposure prophylaxis in coastal Kenya

INTRODUCTION

Retention in preventive care among at-risk men who have sex with men (MSM) is critical for successful prevention of HIV acquisition in Africa. We assessed loss to follow-up (LTFU) rates and factors associated with LTFU in an HIV vaccine feasibility cohort study following MSM with access to pre-exposure prophylaxis (PrEP) in coastal Kenya.

METHODS

Between June 2017 and June 2019, MSM cohort participants attending a research clinic 20 km north of Mombasa were offered daily PrEP and followed monthly for risk assessment, risk reduction counselling and HIV testing. Participants were defined as LTFU if they were late by >90 days for their scheduled appointment. Participants who acquired HIV were censored at diagnosis. Cox proportional hazards models were used to estimate adjusted Hazard Ratio (aHR) of risk factors for LTFU.

RESULTS AND DISCUSSION

A total of 179 participants with a median age of 25.0 years (interquartile range [IQR]: 23.0 to 30.0) contributed a median follow-up time of 21.2 months (IQR: 6.5 to 22.1). Of these, 143 (79.9%) participants started PrEP and 76 (42.5%) MSM were LTFU, for an incidence rate of 33.7 (95% confidence interval [CI], 26.9 to 42.2) per 100 person-years. Disordered alcohol use (aHR: 2.3, 95% CI, 1.5 to 3.7), residence outside the immediate clinic catchment area (aHR: 2.5, 95% CI, 1.3 to 4.6 for Mombasa Island; aHR: 1.8, 95% CI, 1.0 to 3.3 for south coast), tertiary education level or higher (aHR: 2.3, 95% CI, 1.1 to 4.8) and less lead-in time in the cohort prior to 19 June 2017 (aHR: 3.1, 95% CI, 1.8 to 5.6 for zero to three months; aHR: 2.4, 95% CI, 1.2 to 4.7 for four to six months) were independent predictors of LTFU. PrEP use did not differ by LTFU status (HR: 1.0, 95% CI, 0.6 to 1.5). Psychosocial support for men reporting disordered alcohol use, strengthened engagement of recently enrolled participants and focusing recruitment on areas close to the research clinic may improve retention in HIV prevention studies involving MSM in coastal Kenya.

CONCLUSIONS

About one in three participants became LTFU after one year of follow-up, irrespective of PrEP use. Research preparedness involving MSM should be strengthened for HIV prevention intervention evaluations in coastal Kenya.

PrEP uptake and adherence in relation to HIV-1 incidence among Kenyan men who have sex with men

BACKGROUND

Data on HIV-1 incidence following programmatic pre-exposure prophylaxis (PrEP) uptake by men who have sex with men (MSM) are limited in sub-Saharan Africa.

METHODS

Since June 2017, MSM participating in an ongoing cohort study in Kenya were offered daily PrEP, assessed for PrEP uptake and adherence, and evaluated for HIV-1 acquisition monthly. We determined tenofovir-diphosphate (TFV-DP) concentrations in dried blood spots 6-12 months after PrEP initiation, and tenofovir (TFV) concentrations and genotypic drug resistance in plasma samples when HIV-1 infection occurred. We assessed HIV-1 incidence by reported PrEP use.

FINDINGS

Of 172 MSM, 170 (98·8%) were eligible for PrEP, 140 (82·4%) started it, and 64 (57·7%) reported PrEP use at end of study. Of nine MSM who acquired HIV-1 [incidence rate: 3·9 (95% confidence interval (CI), 2·0-7·4) per 100 person-years (PY)], five reported PrEP use at the time of HIV-1 acquisition [incidence rate: 3·6 (95% CI, 1·5-8·6) per 100 PY)] and four had stopped or had never started PrEP [incidence rate: 4·3 (95% CI, 1·6-11·3) per 100 PY]. Among 76 MSM who reported PrEP use, 11 (14·5%) had protective TFV-DP concentrations of ≥700 fmol/punch (≥4 tablets a week). Among the five MSM who acquired HIV-1 while reporting PrEP use, only one had detectable but low TFV concentrations in plasma and none had genotypic HIV-1 resistance.

INTERPRETATION

HIV-1 incidence among MSM with access to programmatic PrEP was high and did not differ by reported PrEP use. Only one in seven MSM taking PrEP had protective tenofovir concentrations and four out of five MSM who acquired HIV-1 while reporting PrEP use had not taken it. Strengthened PrEP adherence support is required among MSM in Kenya.

FUNDING

This work was supported by the International AIDS Vaccine Initiative (IAVI).