HPTN 083-02: factors influencing adherence to injectable PrEP and retention in an injectable PrEP study.

INTRODUCTION: HPTN 083 demonstrated the superiority of long-acting cabotegravir (CAB-LA) versus daily oral emtricitabine/tenofovir disoproxil fumarate (TDF/FTC) as pre-exposure prophylaxis (PrEP) among cisgender men and transgender women who have sex with men (MSM/TGW). HPTN 083 provided the first opportunity to understand experiences with injectable PrEP in a clinical trial. METHODS: Participants from two US sites (Chicago, IL and Atlanta, GA) and one international site (Rio de Janeiro, Brazil) were purposively sampled for individual qualitative interviews (N = 40), between November 2019 and March 2020, to explore trial experiences, barriers to adherence and other factors that may have impacted study implementation or outcomes. The blinded phase ended early due to efficacy; this analysis includes interviews conducted prior to unblinding with three groups defined by adherence (i.e. injection visit attendance): adherent (n = 27), non-adherent (n = 12) and early discontinuers (n = 1). Data were organized using NVivo software and analysed using content analysis. RESULTS: Participants (mean age: 27) were primarily cisgender MSM (90%) and Black/African American (60%). Reasons for trial enrolment and PrEP use included a preference for using HIV prevention medication versus treatment in the event of HIV acquisition; the ability to enhance health via study-related education and services; access to a novel, convenient HIV prevention product at no cost; and contributing to MSM/TGW communities through research. Participants contrasted positive experiences with study staff with their routine clinical care, and emphasized increased scheduling flexibility, thorough communication, non-judgemental counselling and open, affirming environments (e.g. compassion, less stigma) as adherence facilitators. Injection experiences were positive overall; some described early injection-related anxiety, which abated with time and when given some measure of control (e.g. pre-injection countdown), and minimal injection site discomfort. Some concerns and misperceptions about injectable PrEP were reported. Barriers to adherence, across all adherence categories, included structural factors (e.g. financial constraints, travel) and competing demands (e.g. work schedules). CONCLUSIONS: Respondents viewed injectable PrEP trial participation as a positive experience and a means of enhancing wellbeing. Study site flexibility and affirming clinic environments, inclusive of non-judgemental counselling, were key facilitators of adherence. To support injection persistence, interventions that address structural barriers and promote flexible means of injection delivery may be most effective.

Efficacy and safety of long-acting cabotegravir compared with daily oral tenofovir disoproxil fumarate plus emtricitabine to prevent HIV infection in cisgender men and transgender women who have sex with men 1 year after study unblinding: a secondary analysis of the phase 2b and 3 HPTN 083 randomised controlled trial.

BACKGROUND: Injectable cabotegravir was superior to daily oral tenofovir disoproxil fumarate plus emtricitabine for HIV prevention in two clinical trials. Both trials had the primary aim of establishing the HIV prevention efficacy of long-acting injectable cabotegravir pre-exposure prophylaxis (PrEP) compared with tenofovir disoproxil fumarate plus emtricitabine daily oral PrEP. Long-acting PrEP was associated with diagnostic delays and integrase strand-transfer inhibitor (INSTI) resistance. This report presents findings from the first unblinded year of the HIV Prevention Trials Network (HPTN) 083 study. METHODS: The HPTN 083 randomised controlled trial enrolled HIV-uninfected cisgender men and transgender women at elevated HIV risk who have sex with men, from 43 clinical research sites in Africa, Asia, Latin America, and the USA. Inclusion criteria included: a negative HIV serological test at the screening and study entry, undetectable HIV RNA levels within 14 days of study entry, age 18 years or older, overall good health as determined by clinical and laboratory evaluations, and a creatinine clearance of 60 mL/min or higher. Participants were randomly allocated to receive long-acting injectable cabotegravir or daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP. After study unblinding, participants remained on their original regimen awaiting an extension study. HIV infections were characterised retrospectively at a central laboratory. Here we report the secondary analysis of efficacy and safety for the first unblinded year. The primary outcome was incident HIV infection. Efficacy analyses were done on the modified intention-to-treat population using a Cox regression model. Adverse events were compared across treatment groups and time periods (blinded vs unblinded). This trial is registered with ClinicalTrials.gov, NCT02720094. FINDINGS: Of the 4488 participants who contributed person-time to the blinded analysis, 3290 contributed person-time to the first unblinded year analysis between May 15, 2020, and May 14, 2021. Updated HIV incidence in the blinded phase was 0·41 per 100 person-years for long-acting injectable cabotegravir PrEP and 1·29 per 100 person-years for daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP (hazard ratio [HR] 0·31 [95% CI 0·17-0·58], p=0·0003). HIV incidence in the first unblinded year was 0·82 per 100 person-years for long-acting PrEP and 2·27 per 100 person-years for daily oral PrEP (HR 0·35 [0·18-0·69], p=0·002). Adherence to both study products decreased after study unblinding. Additional infections in the long-acting PrEP group included two with on-time injections; three with one or more delayed injections; two detected with long-acting PrEP reinitiation; and 11 more than 6 months after their last injection. Infection within 6 months of cabotegravir exposure was associated with diagnostic delays and INSTI resistance. Adverse events were generally consistent with previous reports; incident hypertension in the long-acting PrEP group requires further investigation. INTERPRETATION: Long-acting injectable cabotegravir PrEP retained high efficacy for HIV prevention in men and transgender women who have sex with men during the first year of open-label follow-up, with a near-identical HR for HIV risk reduction between long-acting injectable cabotegravir and daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP during the first year after unblinding compared with the blinded period. Extended follow-up further defined the risk period for diagnostic delays and emergence of INSTI resistance. FUNDING: Division of AIDS at the National Institute of Allergy and Infectious Diseases, ViiV Healthcare, and Gilead Sciences.

Prevalence of renal and bone risk factors among individuals prescribed oral pre-exposure prophylaxis for HIV.

Objectives: The only available oral pre-exposure prophylaxis (PrEP) regimens approved in the United States to prevent HIV infection during the period covered by this study were emtricitabine/tenofovir alafenamide (F/TAF) and emtricitabine/tenofovir disoproxil fumarate (F/TDF). Both agents have similar efficacy, however F/TAF exhibits improved bone and renal health safety endpoints over F/TDF. In 2021, the United States Preventive Services Task Force recommended individuals have access to the most medically appropriate PrEP regimen. To understand the impact of these guidelines, the prevalence of risk factors to renal and bone health was evaluated among individuals prescribed oral PrEP. Methods: This prevalence study utilized the electronic health records of people prescribed oral PrEP between January 1, 2015 and February 29, 2020. Renal and bone risk factors (age, comorbidities, medication, renal function, and body mass index) were identified using International Classification of Diseases (ICD) and National Drug Code (NDC) codes. Results: Among 40 621 individuals prescribed oral PrEP, 62% had ≥1 renal risk factor and 68% had ≥1 bone risk factor. Comorbidities were the most frequent (37%) class of renal risk factors. Concomitant medications were the most prominent (46%) class of bone-related risk factors. Conclusions: The high prevalence of risk factors suggests the importance of their consideration when choosing the most appropriate regimen for individuals who may benefit from PrEP.

Examining the Role of Autonomy Support, Goal Setting, and Care Coordination Quality on HIV PrEP Adherence in Black Men Who Have Sex with Men: HPTN 073.

Autonomy support is a concept that is derived from self-determination theory. Autonomy refers to the freedom to act as one chooses. The current study aimed to examine if autonomy support was associated with dried blood spot validated pre-exposure prophylaxis (PrEP) adherence, and whether the association was mediated by PrEP adherence goal setting and progress toward PrEP adherence goals. Our sample was drawn from Black men who have sex with men (MSM) from across three cities (Chapel Hill, NC; Los Angeles, CA; and Washington, DC) in the United States between February 2013 and September 2014. We used logistic regression to evaluate associations between study variables and path analysis to test mediation effects. Participants were, on average, 28 [standard deviation (SD) = 1.12] years old and 25% were unemployed. We found that MSM who experienced high autonomy support were more likely to adhere to PrEP [odds ratio (OR) = 1.17; 95% confidence interval: 1.00-1.38]. MSM who set PrEP adherence goals were more likely to adhere to PrEP. Moreover, MSM who reported making progress toward their goals were also more likely to adhere to PrEP. Finally, client perception of coordination quality enhanced the magnitude of the association between goal setting and goal progress and the effect size of goal progress on PrEP adherence. Autonomy support, goal setting, goal monitoring/evaluation, and care coordination quality influenced PrEP adherence among Black MSM. Our findings indicate that while it is important to set goals for PrEP adherence, goal setting may need to be accompanied by progress monitoring to achieve the maximal effect.

Implementation of Client-Centered Care Coordination for HIV Prevention with Black Men Who Have Sex with Men: Activities, Personnel Costs, and Outcomes-HPTN 073.

BACKGROUND: Black men who have sex with men (MSM) experience disproportionate rates of HIV infection in the USA, despite being no more likely to engage in sexual risk behaviors than other MSM racial/ethnic groups. HIV pre-exposure prophylaxis (PrEP) has been shown to reduce risk of HIV acquisition; however, rates of PrEP use among Black MSM remain low. Clinical, psychosocial, and structural factors have been shown to impact PrEP use and adherence among Black MSM. Care coordination of HIV prevention services has the potential to improve PrEP use and adherence for Black MSM, as it has been shown to improve HIV-related care outcomes among people living with HIV. METHODS: Client-centered care coordination (C4) is a multi-level intervention designed to address clinical, psychosocial, and structural barriers to HIV prevention services for Black MSM within HPTN 073, a PrEP demonstration project among Black MSM in three cities in the USA. The current study examined the implementation process of C4, specifically investigating the activities, cost, time, and outcomes associated with the C4 intervention. RESULTS: On average, participants engaged in five care coordination encounters. The vast majority of care coordination activities were conducted by counselors, averaging 30 min per encounter. The cost of care coordination was relatively low with a mean cost of $8.70 per client encounter. CONCLUSION: Although client-centered care coordination was initially implemented in well-resourced communities with robust HIV research and service infrastructure, our findings suggest that C4 can be successfully implemented in resource constrained communities.

Freedom as Prevention: Mechanisms of Autonomy Support for Promoting HIV Pre-Exposure Prophylaxis Use and Condom Use among Black MSM in 3 US Cities-HPTN 073.

Healthcare providers who use controlling or coercive strategies may compel short-term enactment of HIV and sexually transmitted infection prevention behaviors but may inadvertently undermine their client's motivation to maintain those behaviors in the absence of external pressure. Autonomous motivation refers to the self-emanating and self-determined drive for engaging in health behaviors. It is associated with long-term maintenance of health behaviors. We used structural equation modeling to investigate whether autonomy support was associated with increased odds of therapeutic serum levels of pre-exposure prophylaxis, through a pathway that satisfies basic psychological needs for autonomous self-regulation and competence regarding pre-exposure prophylaxis use. We also investigated whether autonomy support was associated with decreased odds of condomless anal intercourse via the same psychological needs-satisfaction pathway of autonomous self-regulation and competence regarding condom use. We tested these two theorized pathways using secondary data from a longitudinal sample of Black men who have sex with men from across three cities in the US (N = 226). Data from the sample fit the theorized models regarding the pathways by which autonomy support leads to the presence of therapeutic PrEP levels in serum (χ2 = 0.56; RMSEA = 0.04; CFI = .99, TLI = 0.98) and how it also leads to decreased odds of condomless anal intercourse (χ2 = 0.58; RMSEA = 0.03; CFI = 0.99; TLI = 0.98). These findings provide scientific evidence for the utility of self-determination theory as a model to guide intervention approaches to optimize the implementation and impact of PrEP for Black men who have sex with men.

Optimizing PrEP Continuance: A Secondary Analysis Examining Perceived Autonomy Support and Care Coordination Quality among Black MSM in HPTN 073.

At the end of year 2018, it was estimated that in the United States over 1 million people were living with HIV. Although Black/African American individuals comprise an estimated 13.4% of the US population, as of 2019, they represented an estimated 42% of all new HIV diagnoses in 2018. PrEP use among Black men who have sex with men has not reached levels sufficient to have a population impact on HIV incidence. The purpose of this study was to examine whether high perceived autonomy support and care coordination quality were associated with PrEP continuation. Secondary analyses were conducted on data with 226 Black MSM in three US cities. Participants who were PrEP users and scored higher on autonomy support at week 8 were significantly more likely to continue PrEP (OR 1.48; 95% CI 1.04-2.11). Perception of coordination quality did not differ between PrEP users and non-users at any of the visits. Although coordination quality was not statistically significant, greater than half of PrEP users and non-PrEP users utilized the C4 services. Addressing social, individual, and structural barriers to PrEP may benefit Black MSM irrespective of their PrEP use.

HIV care continuum interventions for Black men who have sex with men in the USA.

Disparities persist along the HIV care continuum among Black men who have sex with men (MSM) in the USA. As part of an initiative funded by the Health Resources and Services Administration's HIV/AIDS Bureau (US Department of Health and Human Services), we searched for recently published interventions focused on improving HIV care continuum outcomes among Black MSM with HIV in the USA. Our search identified 14 interventions, all of which were associated with at least one statistically significant outcome. Medication adherence was the most common outcome of interest, and linkage to care was the least common. More than half of the interventions focused on younger populations and took place in the US South. Interventions used a range of strategies to increase cultural relevance and address common barriers to optimal HIV outcomes for Black MSM. Several interventions harnessed social media, text messaging, and smartphone apps to facilitate social support, deliver HIV education, and encourage medication adherence. Interventions were delivered mostly at the individual or interpersonal level, although three made system-level changes to address structural barriers. Notably missing were interventions focused on minimising behavioural health barriers, and interventions directly addressing social determinants of health such as housing. To accelerate the pace of implementation and scale-up of interventions for Black MSM with HIV, public health entities can pilot emerging interventions in real-world settings, and use an implementation science approach to evaluate outcomes and assess the implementation strategies that drive or hinder effectiveness.

Long-Lived Organotypic Slice Culture Model of the Rat Basolateral Amygdala.

Organotypic slice cultures (OTCs) have been employed in the laboratory since the early 1980s and have proved to be useful for the study of a number of neural systems. Our recent work focuses on the development of behavioral stress resilience induced by repeated daily injections of neuropeptide Y into the basolateral amygdala (BLA). Resilience develops over weeks, persisting to 8 weeks. To unravel the cellular mechanisms underlying neuropeptide Y-induced stress resilience we developed in vitro OTCs of the BLA. Here, we provide an optimized protocol that consistently yields viable and healthy OTCs containing the BLA and surrounding tissue using the interface method, prepared with slices taken from postnatal (P) day 14 rats. We explain key points to optimizing tissue viability and discuss mitigation or avoidance of pitfalls that can arise to aid in successful implementation of this technique. We show that principal neurons in BLA OTCs (8 weeks in vitro = equivalent postnatal day 70) develop into networks that are electrophysiologically very similar to those from acute slices obtained from older rats (P70) and respond to pharmacological treatments in a comparable way. Furthermore, we highlight how these cultures be used to further understand the molecular, cellular, and circuit-level neuropathophysiological changes underlying stress disorders. BLA OTCs provide long-term physiological and pharmacological results whose predictions were borne out in vivo, supporting the validity of the BLA OTC as a model to unravel BLA neurocircuitry. Recent preliminary results also support the successful application of this approach to preparing long-lived OTCs of BLA and neocortex from mice. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Organotypic slice culture Support Protocol 1: Changing medium Support Protocol 2: Drug incubations Basic Protocol 2: Excision of OTC slices from inserts Support Protocol 3: Fixation of slices.

Sexual Risk Profiles Among Black Sexual Minority Men: Implications for Targeted PrEP Messaging.

Black gay, bisexual, and other Black sexual minority men (BSMM) continue to experience some of the largest sexual health disparities in the U.S. Engaging BSMM in PrEP is crucial to improving sexual health outcomes and reducing disparities. However, knowledge of the profiles of sexual risk and PrEP initiation among this group is limited. This study used latent class analysis to identify HIV risk and PrEP initiation patterns among BSMM in the HPTN 073 Study (n = 226). Guided by current Centers for Disease Control screening guidelines, latent class indicators included relationship status, condom use, number of sexual partners, substance use, sexually transmitted infection (STI) history, and partner HIV status. Age and PrEP initiation were used in a multinomial regression to identify correlates of class membership. Three latent classes were identified: Single, Condomless Partners, Single, Multiple Partners, and Serodiscordant Partners. Single, Condomless Partners had the highest conditional probabilities of having greater than three male partners, substance use before sex, and receiving an STI diagnosis. Serodiscordant Partners had a 100% conditional probability of condomless sex and having a male partner living with HIV. BSMM who initiated PrEP were less likely to be classified as Single, Condomless Partners than Serodiscordant Partners (AOR = 0.07, 95% CI = 0.02, 0.66). Findings support the need for culturally relevant tailored and targeted messaging for BSMM with multiple sexual risk indicators.

Cabotegravir for HIV Prevention in Cisgender Men and Transgender Women.

BACKGROUND: Safe and effective long-acting injectable agents for preexposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) infection are needed to increase the options for preventing HIV infection. METHODS: We conducted a randomized, double-blind, double-dummy, noninferiority trial to compare long-acting injectable cabotegravir (CAB-LA, an integrase strand-transfer inhibitor [INSTI]) at a dose of 600 mg, given intramuscularly every 8 weeks, with daily oral tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) for the prevention of HIV infection in at-risk cisgender men who have sex with men (MSM) and in at-risk transgender women who have sex with men. Participants were randomly assigned (1:1) to receive one of the two regimens and were followed for 153 weeks. HIV testing and safety evaluations were performed. The primary end point was incident HIV infection. RESULTS: The intention-to-treat population included 4566 participants who underwent randomization; 570 (12.5%) identified as transgender women, and the median age was 26 years (interquartile range, 22 to 32). The trial was stopped early for efficacy on review of the results of the first preplanned interim end-point analysis. Among 1698 participants from the United States, 845 (49.8%) identified as Black. Incident HIV infection occurred in 52 participants: 13 in the cabotegravir group (incidence, 0.41 per 100 person-years) and 39 in the TDF-FTC group (incidence, 1.22 per 100 person-years) (hazard ratio, 0.34; 95% confidence interval, 0.18 to 0.62). The effect was consistent across prespecified subgroups. Injection-site reactions were reported in 81.4% of the participants in the cabotegravir group and in 31.3% of those in the TDF-FTC group. In the participants in whom HIV infection was diagnosed after exposure to CAB-LA, INSTI resistance and delays in the detection of HIV infection were noted. No safety concerns were identified. CONCLUSIONS: CAB-LA was superior to daily oral TDF-FTC in preventing HIV infection among MSM and transgender women. Strategies are needed to prevent INSTI resistance in cases of CAB-LA PrEP failure. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 083 ClinicalTrials.gov number, NCT02720094.).

Syngap1 regulates experience-dependent cortical ensemble plasticity by promoting in vivo excitatory synapse strengthening.

A significant proportion of autism risk genes regulate synapse function, including plasticity, which is believed to contribute to behavioral abnormalities. However, it remains unclear how impaired synapse plasticity contributes to network-level processes linked to adaptive behaviors, such as experience-dependent ensemble plasticity. We found that Syngap1, a major autism risk gene, promoted measures of experience-dependent excitatory synapse strengthening in the mouse cortex, including spike-timing-dependent glutamatergic synaptic potentiation and presynaptic bouton formation. Synaptic depression and bouton elimination were normal in Syngap1 mice. Within cortical networks, Syngap1 promoted experience-dependent increases in somatic neural activity in weakly active neurons. In contrast, plastic changes to highly active neurons from the same ensemble that paradoxically weaken with experience were unaffected. Thus, experience-dependent excitatory synapse strengthening mediated by Syngap1 shapes neuron-specific plasticity within cortical ensembles. We propose that other genes regulate neuron-specific weakening within ensembles, and together, these processes function to redistribute activity within cortical networks during experience.

Patient-Focused Selection of PrEP Medication for Individuals at Risk of HIV: A Narrative Review.

Pre-exposure prophylaxis (PrEP) medication is a key component of the HIV prevention strategy in the US, which has been demonstrated to be highly effective in preventing HIV acquisition among individuals at risk. Two PrEP medications are currently approved: emtricitabine/tenofovir disoproxil fumarate (Truvada®; F/TDF) was approved by the US Food and Drug Administration in 2012, followed by emtricitabine/tenofovir alafenamide (Descovy®; F/TAF) in 2019. An ongoing randomized, double-blind, Phase 3 study (DISCOVER) demonstrated that F/TAF had non-inferior efficacy to F/TDF. While both medications have been found to be efficacious and well tolerated, several studies have identified that important differences exist with regards to pharmacokinetics, bone and renal safety profiles, and other factors. In this narrative review, we conducted a comprehensive evaluation of the populations at risk of HIV who may also be affected by, or at risk of, bone or renal conditions. We reviewed the safety profiles of F/TDF and F/TAF to develop an evidence-based algorithm for selecting the appropriate PrEP medication, based on biological, behavioral, and health characteristics of an individual at risk of HIV, and considered how the choice of PrEP medication may or may not compound safety concerns for these individuals. We identified that the introduction of F/TAF provides a valuable alternative to F/TDF, allowing the personalization of PrEP. F/TAF may be the preferred medication for cisgender men and transgender women at risk of HIV infection who are predisposed to, or already have, bone or renal conditions. While the approval of F/TAF is the first step in personalization of PrEP, additional options are still warranted to help accommodate the wide spectrum of individuals at risk of HIV with different lifestyles, medical histories, preferences, and requirements.

Pre-exposure prophylaxis (or PrEP) prevents HIV acquisition in individuals at risk of HIV infection. There are currently two approved options for PrEP in the US; both are oral medications. The first option, approved in 2012, is a combination of two drugs called emtricitabine/tenofovir disoproxil fumarate­also known as Truvada^® or F/TDF. The second option, approved in 2019, is a combination of emtricitabine and a different prodrug, tenofovir alafenamide­this combination is called Descovy^® or F/TAF. Both options are 99% effective in preventing HIV if taken daily. While the risk of serious side effects from taking either of the PrEP medications is low, F/TAF has demonstrated less effect on bone and kidney health, and may be the preferred option in people with bone or kidney conditions, or in those at risk of developing osteoporosis or having risk factors for kidney disease, such as people living with diabetes or high blood pressure. As the risk of HIV sometimes overlaps with risks to bone and renal health according to race/ethnicity, poverty, alcohol/substance use, smoking tobacco, and taking other medications, F/TAF as an alternative PrEP medication allows the PrEP choice to depend on the broader health conditions of the individual. 'Personalized medicine' means that medicines can be chosen to suit an individual's biology, behavior, lifestyle, and overall health. The approval of F/TAF is the first step in personalization of PrEP medication, while additional options need to be researched to meet the requirements of all individuals at risk of HIV.

Contribution of NPY Y5 Receptors to the Reversible Structural Remodeling of Basolateral Amygdala Dendrites in Male Rats Associated with NPY-Mediated Stress Resilience.

Endogenous neuropeptide Y (NPY) and corticotrophin-releasing factor (CRF) modulate the responses of the basolateral amygdala (BLA) to stress and are associated with the development of stress resilience and vulnerability, respectively. We characterized persistent effects of repeated NPY and CRF treatment on the structure and function of BLA principal neurons in a novel organotypic slice culture (OTC) model of male rat BLA, and examined the contributions of specific NPY receptor subtypes to these neural and behavioral effects. In BLA principal neurons within the OTCs, repeated NPY treatment caused persistent attenuation of excitatory input and induced dendritic hypotrophy via Y5 receptor activation; conversely, CRF increased excitatory input and induced hypertrophy of BLA principal neurons. Repeated treatment of OTCs with NPY followed by an identical treatment with CRF, or vice versa, inhibited or reversed all structural changes in OTCs. These structural responses to NPY or CRF required calcineurin or CaMKII, respectively. Finally, repeated intra-BLA injections of NPY or a Y5 receptor agonist increased social interaction, a validated behavior for anxiety, and recapitulated structural changes in BLA neurons seen in OTCs, while a Y5 receptor antagonist prevented NPY's effects both on behavior and on structure. These results implicate the Y5 receptor in the long-term, anxiolytic-like effects of NPY in the BLA, consistent with an intrinsic role in stress buffering, and highlight a remarkable mechanism by which BLA neurons may adapt to different levels of stress. Moreover, BLA OTCs offer a robust model to study mechanisms associated with resilience and vulnerability to stress in BLA.SIGNIFICANCE STATEMENT Within the basolateral amygdala (BLA), neuropeptide Y (NPY) is associated with buffering the neural stress response induced by corticotropin releasing factor, and promoting stress resilience. We used a novel organotypic slice culture model of BLA, complemented with in vivo studies, to examine the cellular mechanisms associated with the actions of NPY. In organotypic slice cultures, repeated NPY treatment reduces the complexity of the dendritic extent of anxiogenic BLA principal neurons, making them less excitable. NPY, via activation of Y5 receptors, additionally inhibits and reverses the increases in dendritic extent and excitability induced by the stress hormone, corticotropin releasing factor. This NPY-mediated neuroplasticity indicates that resilience or vulnerability to stress may thus involve neuropeptide-mediated dendritic remodeling in BLA principal neurons.

House Ball Community Leaders' Perceptions of HIV and HIV Vaccine Research.

BACKGROUND OR OBJECTIVES: Worldwide, men who have sex with men (MSM) and Transgender persons are vulnerable to psychosocial factors associated with high risk for HIV, and suffer disproportionately high rates of HIV/AIDS. In the United States (US), the House Ball Community (HBC) is a social network comprised predominantly of Black and Hispanic MSM and Transgender persons who reside in communal settings. This study explores Western New York HBC leaders' perceptions of HIV in their communities and their knowledge of HIV prevention strategies, including HIV vaccine trials. METHODS: The project was conducted using an exploratory approach based on the principles of Community-Based Participatory Research (CBPR) methods. An HIV behavioral risk assessment provided descriptive data, while qualitative measures explored psychosocial and behavioral factors. RESULTS: Behavioral assessments indicated high levels of risky sexual behaviors and experiences of violence. Interviews with 14 HBC leaders revealed that knowledge of HIV and local HIV vaccines trials was limited. Barriers to HIV knowledge included fear of peer judgment, having inaccurate information, and lack of formal education. Experiencing violence was identified as barrier to positive health behavior. Nevertheless, the HBC was described as a safe and creative space for marginalized MSM and Transgender youth. CONCLUSION AND GLOBAL HEALTH IMPLICATIONS: Findings suggest that the interrelation between health problems and social context amplify HIV risk in the HBC. The organizational structure and resources of the HBC, and MSM/Transgender communities worldwide can be instrumental in informing interventions to address HIV-related risk behaviors and create appropriate recruitment tools to ensure their representation in HIV research.

Development of a Black Caucus within the HIV Prevention Trials Network (HPTN): Representing the Perspectives of Black Men Who Have Sex with Men (MSM).

Black men who have sex with men (MSM) have disproportionate HIV disease burden in the United States. Black MSM have been underrepresented in biomedical research, including HIV clinical trials, due to a myriad of socio-structural, socio-cultural, and psychosocial factors. The HIV Prevention Trials Network (HPTN) 061, a feasibility study of a multi-component HIV prevention intervention for Black MSM in six US cities, incorporated the development and implementation of a Black Caucus as a culturally grounded model for the integration of Black MSM in clinical trials and research in HPTN. Based on a qualitative methodological approach, we describe the formation and implementation of the Black Caucus from the perspective of Black MSM key community stakeholders. Three major themes emerged from the qualitative narratives: (1) the role of the Black Caucus in shaping the HPTN, (2) how the Black Caucus addresses the needs of Black MSM communities pertaining to the influence of race and sexual identity, and (3) socio-cultural needs of Black MSM. These findings have implications for the provision of culturally congruent expertise, community engagement, cultural mistrust, recruitment and retention of Black MSM in HIV clinical trials, culturally-relevant study design and implementation, and the role of developing Black MSM prevention researchers.

Changes in Sexual and Gender Identity and Their Associations with Internalized Homophobia Among Black Men Who Have Sex with Men in the HPTN 061 BROTHERS Cohort.

Sexual and gender identity have frequently been assessed in public health research as static states. However, a substantial and growing body of evidence indicates that both identities may have greater potential for change over time than once supposed. Despite this evidence, research into adult identity change remains relatively limited. Using longitudinal data from 1553 Black men who have sex with men (BMSM) aged 18-68 years and recruited from study locations in six major cities across the country, we examined changes in sexual and gender identities over a period of 12 months. The results showed that sexual and gender identity did indeed change among adult BMSM. Additionally, we explored internalized homophobia (IH) as a potential driver of identity change and found that IH significantly impacts the degree and direction of change, with individuals who reported higher baseline IH more likely to demonstrate a shift toward a heterosexual/straight identity at 6 and 12 months. The results are discussed in light of what is known and unknown regarding identity change, and potential avenues for future research are explored.

NPY2 Receptors Reduce Tonic Action Potential-Independent GABAB Currents in the Basolateral Amygdala.

Although NPY has potent anxiolytic actions within the BLA, selective activation of BLA NPY Y2 receptors (Y2Rs) acutely increases anxiety by an unknown mechanism. Using ex vivo male rat brain slice electrophysiology, we show that the selective Y2R agonist, [ahx5-24]NPY, reduced the frequency of GABAA-mediated mIPSCs in BLA principal neurons (PNs). [ahx5-24]NPY also reduced tonic activation of GABAB receptors (GABABR), which increased PN excitability through inhibition of a tonic, inwardly rectifying potassium current (KIR ). Surprisingly, Y2R-sensitive GABABR currents were action potential-independent, persisting after treatment with TTX. Additionally, the Ca2+-dependent, slow afterhyperpolarizing K+ current (IsAHP ) was enhanced in approximately half of the Y2R-sensitive PNs, possibly from enhanced Ca2+ influx, permitted by reduced GABABR tone. In male and female mice expressing tdTomato in Y2R-mRNA cells (tdT-Y2R mice), immunohistochemistry revealed that BLA somatostatin interneurons express Y2Rs, as do a significant subset of BLA PNs. In tdT-Y2R mice, [ahx5-24]NPY increased excitability and suppressed the KIR in nearly all BLA PNs independent of tdT-Y2R fluorescence, consistent with presynaptic Y2Rs on somatostatin interneurons mediating the above effects. However, only tdT-Y2R-expressing PNs responded to [ahx5-24]NPY with an enhancement of the IsAHP Ultimately, increased PN excitability via acute Y2R activation likely correlates with enhanced BLA output, consistent with reported Y2R-mediated anxiogenesis. Furthermore, we demonstrate the following: (1) a novel mechanism whereby activity-independent GABA release can powerfully dampen BLA neuronal excitability via postsynaptic GABABRs; and (2) that this tonic inhibition can be interrupted by neuromodulation, here by NPY via Y2Rs.SIGNIFICANCE STATEMENT Within the BLA, NPY is potently anxiolytic. However, selective activation of NPY2 receptors (Y2Rs) increases anxiety by an unknown mechanism. We show that activation of BLA Y2Rs decreases tonic GABA release onto BLA principal neurons, probably from Y2R-expressing somatostatin interneurons, some of which coexpress NPY. This increases principal neuron excitability by reducing GABAB receptor (GABABR)-mediated activation of G-protein-coupled, inwardly rectifying K+ currents. Tonic, Y2R-sensitive GABABR currents unexpectedly persisted in the absence of action potential firing, revealing, to our knowledge, the first report of substantial, activity-independent GABABR activation. Ultimately, we provide a plausible explanation for Y2R-mediated anxiogenesis in vivo and describe a novel and modulatable means of damping neuronal excitability.

Pre-exposure prophylaxis initiation and adherence among Black men who have sex with men (MSM) in three US cities: results from the HPTN 073 study.

INTRODUCTION: Randomized clinical trials have demonstrated the efficacy of antiretroviral pre-exposure prophylaxis (PrEP) in preventing HIV acquisition among men who have sex with men (MSM). However, limited research has examined initiation and adherence to PrEP among Black MSM (BMSM) in the United States (US) who are disproportionately represented among newly HIV infected and late to care individuals. This research reports on the HIV Prevention Trials Network 073 (HPTN 073) study aimed to examine PrEP initiation, utilization and adherence among Black MSM utilizing the theoretically principled, culturally informed and client-centered care coordination (C4) model. METHODS: The HPTN 073 study enrolled and followed 226 HIV-uninfected Black MSM in three US cities (Los Angeles, CA; Washington DC; and Chapel Hill, NC) from February 2013 through September 2015. Study participants were offered once daily oral emtricitabine/tenofovir (FTC/TDF) PrEP combined with C4 and followed up for 52 weeks. Participants received HIV testing, risk reduction education and clinical monitoring. RESULTS: Of the 226 men enrolled, 178 participants initiated PrEP (79%), and of these 64% demonstrated PrEP utilization at week 26 (mid-point of the study) based on pharmacokinetic testing. Condomless anal sex with an HIV-infected or unknown status casual male partner was statistically significantly associated with a greater likelihood of PrEP initiation (adjusted odds ratio (OR) 4.4, 95% confidence interval (CI) 1.7, 11.7). Greater age (≥25 vs. <25, OR 2.95, 95% CI 1.37 -6.37), perception of having enough money (OR 3.6, 95% CI 1.7 to 7.7) and knowledge of male partner taking PrEP before sex (OR 2.22, 95% CI 1.03 to 4.79) were statistically significantly associated with increased likelihood of PrEP adherence at week 26. Annualized HIV incidence was 2.9 (95% CI 1.2 to 7.9) among those who initiated PrEP, compared to 7.7 (95% CI 2.5 to 24.1) among those who did not initiate PrEP (p = 0.18). CONCLUSIONS: Results suggest a high level of PrEP initiation among at-risk Black MSM, a group historically characterized as hard to reach. The data support the importance of addressing contextual factors that affect PrEP initiation and adherence, and of additional research on the ultimate benefit of PrEP in HIV prevention among Black MSM.

Incidence and Correlates of Sexually Transmitted Infections Among Black Men Who Have Sex With Men Participating in the HIV Prevention Trials Network 073 Preexposure Prophylaxis Study.

BACKGROUND: The HIV Prevention Trials Network (HPTN) Study 073 (HPTN 073) assessed the feasibility, acceptability, and safety of preexposure prophylaxis (PrEP) for black men who have sex with men (BMSM). The purpose of this analysis was to characterize the relationship between PrEP uptake and use and incident sexually transmitted infections (STIs) among participants enrolled in HPTN 073. METHODS: A total of 226 human immunodeficiency virus (HIV)-uninfected BMSM were enrolled in 3 US cities; all participants received client-centered care coordination (C4) and were offered daily oral PrEP. Participants were followed for 12 months with STI testing (rectal and urine nucleic acid amplification test for gonorrhea and chlamydia, rapid plasma reagin for syphilis) conducted at baseline, week 26, and week 52. Logistic regression was used to examine associations between STI incidence and PrEP uptake. Generalized estimating equations were used to evaluate associations between age, PrEP acceptance, sexual behaviors, and incident STIs. RESULTS: Baseline STI prevalence was 14.2%. Men aged <25 years were more likely to have a baseline STI (25.3% vs 6.7%; odds ratio [OR], 4.39; 95% confidence interval [CI:, 1.91, 10.11). Sixty participants (26.5%) acquired ≥1 STI during follow-up; the incidence rate was 34.2 cases per 100 person-years (95% CI, 27.4, 42.9). In adjusted analyses, baseline STI diagnosis (OR, 4.23; 95% CI, 1.82, 9.87; P < .001) and additional C4 time (OR, 1.03; 95% CI, 1.00, 1.06; P = .027) were associated with having an incident STI. STI incidence was not associated with PrEP acceptance or adherence. CONCLUSIONS: While we found higher rates of STIs in younger BMSM, overall rates of STI were lower than in prior PrEP trials, with no increase over time. BMSM with STIs at PrEP initiation may require additional interventions that target STI acquisition risk. CLINICAL TRIALS REGISTRATION: NCT01808352.