Retention in event-driven PrEP among young Thai men who have sex with men at risk of HIV acquisition.

Background: Daily pre-exposure prophylaxis (PrEP) regimen of tenofovir/emtricitabine (TDF/FTC) tablet is the standard of care for HIV prevention in Thailand. Event-driven PrEP (ED-PrEP), taking two loading pills 2-24 h prior to sex and two doses afterward, is considered an alternative regimen. This pilot study aimed to describe accuracy of and retention in ED-PrEP use among Thai young men who have sex with men (YMSM).Methods: A cohort of YMSM aged 15-19 years at risk of HIV infection, defined as reporting irregular condom use or having an HIV-positive sexual partner, was enrolled. All participants were provided oral TDF/FTC, condoms, and the "Raincoat" mobile application, which reminds users when to administer ED-PrEP. Participants attended clinic visits at Months 1, 3, and 6 and followed up by phone at Months 2, 4, and 5. Proper use of ED-PrEP was reported in person-months.Results: From August 2020 to July 2021, 36 YMSM with a median age of 18.7 (IQR, 17.5-19.4) years were enrolled. Thirty-two participants (88.9%, 95% CI: 73.9-96.9%) were retained at 6 months. No HIV incidence occurred during this study period. Of 197 person-months of follow-up, 69 (35%) involved sexual activity. In this group, 61% used ED-PrEP correctly. "Unplanned sexual activity" was the most commonly cited reason for incorrect use.Conclusions: YMSM who have infrequent sex had very high retention in ED-PrEP. However, about one-third of the sexually active period, ED-PrEP was not used correctly due to not taking the loading dose, suggesting that this regimen may not be suitable for unanticipated sexual activity.

Sexually transmitted infections incidence in young Thai men who have sex with men and transgender women using HIV pre-exposure prophylaxis.

BACKGROUND: Sexually transmitted infections are a major public health issue worldwide. HIV pre-exposure prophylaxis (PrEP) use among youth may be associated with increased incidence of sexually transmitted infections (STIs). OBJECTIVES: To measure the prevalence and incidence of STIs among young men who have sex with men (YMSM) and young transgender women (YTGW) using PrEP. METHODS: A prospective cohort of 15- to 19-year-old YMSM and YTGW with HIV risk defined as inconsistent condom use and/or multiple sex partners were enrolled. Participants were provided daily oral tenofovir disoproxil fumarate/emtricitabine. STI screening was done at baseline and month 6 for syphilis, urine, and anal swab nucleic acid amplification testing for C. trachomatis (CT) and N. gonorrheaoe (NG). RESULTS: From March 2018 to June 2019, 200 adolescents (147 MSM and 53 TGW) with a median (IQR) age of 18 years (17-19) were enrolled. STI prevalence was 22.5% (95% CI 16.7-28.3). STI incidence was 25.2 per 100 person-years (95% CI 14.7, 40.3). Factors associated with STI incidence were self-reported >2 sex partners in the past month (unadjusted rate ratio [uRR] 4.6, 95% CI 1.0, 20.6), and moderate PrEP adherence (uRR 7.3, 95% CI 1.6, 32.6). CONCLUSIONS: STI incidence in YMSM and YTGW PrEP users was high at approximately one in five. Regular screening and treatment of STIs should be implemented in youth HIV prevention packages.

Preference and ability to perform blood-versus oral-fluid-based HIV self-testing in adolescents and young adults in Bangkok.

Introduction: Adolescents and young adults (AYA) have limited access to HIV screening tests despite the risk of acquiring HIV infection. This study aims to understand AYA preferences and their ability to perform HIV self-tests (HIVST).Methods: A cross-sectional study looked at AYA preferences when offered a choice between blood-based (INSTI®) and oral fluid-based (OraQuick®) HIVST. Adolescents and young adult participants between 18 and 24 years-old who report inconsistent condom use or had a history of sexually transmitted diseases were enrolled. Participants were offered a choice between blood-based and/or oral fluid-based HIVSTs with explanations of the differences between two types. Then, written and short video instructions according to the chosen type were given before participants performed a test. The study seeks to understand test preference, ability to perform and interpret test results.Results: From March to April 2021, 87 AYA were enrolled with a median age of 20 years (interquartile range (IQR) 18-22). Of the participants, 54 (62.1%) were men who have sex with men (MSM), 25 (28.7%) were cisgender men or women and 8 (9.2%) were transgender women (TGW). There were 37 (42.5%) first-time HIV testers and 32 (36.8%) HIV PrEP users. There were 57 participants (65.6%, 95% CI 54.6%-75.4%) that preferred blood-based HIVSTs. Reasons for preferring blood-based testing were the rapid results (77.2%) and higher accuracy (66.7%). The ability to perform and interpret HIVST results were 89.5% and 98% among INSTI users and 93.3% and 100.0% among OraQuick® users. None was HIV-positive. Moreover, 13.8% of the participants initiated same-day pre-exposure prophylaxis (PrEP).Conclusions: Thai AYA preferred blood-based over oral fluid-based HIVSTs. Most AYAs were able to perform the HIVSTs and interpret results. Supervision and post-test counselling of HIVSTs should be implemented to ensure AYA gain benefits from HIVSTs.

Acceptability of blood-based HIV self-testing among adolescents aged 15-19 years at risk of HIV acquisition in Bangkok.

INTRODUCTION: Young men who have sex with men (YMSM) and young transgender women (YTGW) in Thailand are at high HIV risk. HIV self-tests (HIVSTs) are rapidly administrable and prompt linkage to HIV treatment or prevention services. This study assesses the acceptability and feasibility of blood-based HIVST use in adolescents. METHODS: A cross-sectional study was conducted among YMSM and YTGW aged 15-19 years with HIV acquisition risk. Participants completed questionnaires on the HIVST and then administered INSTI® independently, an HIVST immunoassay detecting gp41 and gp36 antibodies from finger-stick blood. Confirmatory HIV antibody tests were performed. RESULTS: Between July and September 2020, 90 adolescents were enrolled. Mean (SD) age was 17.6 (1.1) years. Half (N = 45) were YMSM. Forty-six (51%) were first-time HIV testers, and 32 (36%) had "ever used" HIV pre-exposure prophylaxis (PrEP). Two (2.2%, 95% CI: 0.0-5.3) tested positive, 21 (23.4%) invalid, and 67 (74.4%) negative. Invalidity causes included 17 (81%) insufficient blood, 3 (14%) buffer spillage, and 1 (5%) procedural missteps; all had negative HIV antibody tests. HIV self-test acceptability was 87.8% (95% CI: 81.0-94.5). Most (79%) preferred HIVST performance in hospital rather than at home. CONCLUSIONS: HIVSTs are acceptable in HIV at-risk adolescents. Blood-based HIVSTs should be positioned as rapid point-of-care tests with real-time linkage to HIV services.

Improving Methods to Classify Perinatal versus Nonperinatal HIV Acquisition in Young Adolescents 10-14 Years of Age.

Mode of HIV acquisition for adolescents with HIV is often not recorded within routine healthcare databases. Hence, age at enrollment in HIV care is often used as a proxy for perinatal versus nonperinatal infection. Using routine cohort data from adolescents presenting for HIV care 10-14 years of age, we developed logistic regression models to predict likely mode of infection.