Characterizing PrEP Adherence and Patterns of Use in a Diverse Community Cohort of Young Men

项目摘要 与男性发生性关系的年轻男性（YMSM）感染艾滋病毒的风险很高，特别是有色人种的YMSM。暴露前 预防性治疗（PrEP）在减少艾滋病毒传播方面非常有效。摄取量低于 预计，但正在迅速增加，但在黑人YMSM中较少。PrEP的有效性取决于 坚持，但坚持的水平各不相同，往往是较低的黑人个人和青年。粘附 每日PrEP不需要完美才能获得益处-在iPrEx开放标签扩展中，服用2-3 剂量/周的有效性为84%（4+为100%有效）-并且非每日给药策略也在 研究（事件和时间驱动的给药）。除了坚持之外，使用模式也至关重要。口服 PrEP不太可能成为大多数人的终身策略，有证据表明许多YMSM停止PrEP （特别是黑人和拉丁裔YMSM），但大多数中止报告继续艾滋病毒的危险行为。此外，本发明还 研究开始检查在最高艾滋病毒风险的离散时期期间的间歇性PrEP使用。最后，风险 补偿（即，开始PrEP后避孕套使用减少）是PrEP有效性的关键组成部分 因为如果坚持不理想，它可能会维持甚至增加艾滋病毒的传播。当前的目标 建议是表征不同给药策略的PrEP依从性，描述使用模式（连续， 间歇性，停药），并检查在坚持和使用模式的种族差异。我们将嵌入 RADAR的一项新的混合方法研究，一个多样化的YMSM队列（N> 1，200;年龄16-29）评估了每个 6个月（U 01 DA 036939）。我们建议增加PrEP使用者的每日日记研究，以描述依从性 和使用模式，坚持客观衡量PrEP覆盖率的生物标志物，以及深入访谈 与PrEP用户一起了解这些问题的背景影响。目的1：描述PrEP依从性、剂量 策略和使用模式。我们将对120名YMSM进行为期3个月的每日日记研究 PrEP用户从雷达：a）表征PrEP给药策略的模式（每日，时间驱动，事件- 驱动），依从性和使用模式（连续，间歇，中止）; B）检查PrEP是否 依从性或给药策略与自我报告的性风险行为和STI感染相关;以及c） 描述PrEP依从性、给药策略和风险补偿的种族差异。目标2：评估 使用模式与红细胞中PrEP的长期和短期浓度之间的关联。我们 将在日记研究期间每月采集一次干血斑样本（3x），以评估 替诺福韦-二磷酸和恩曲他滨-三磷酸。目标3：描述YMSM对坚持的观点， 使用模式和风险补偿。我们将对60名YMSM进行深度访谈日记研究 参与者了解个人，人际和结构对PrEP依从性和模式的影响 使用，重点是理解种族差异。这项研究的数据将为开发 公共卫生信息和行为干预措施，以提高不同YMSM之间的PrEP有效性。

Project Summary Young men who have sex with men (YMSM) are at high risk for HIV–particularly YMSM of color. Pre-exposure prophylaxis (PrEP) is extremely effective at reducing HIV transmission. Uptake has been lower than anticipated, but is increasing rapidly–though less so among Black YMSM. PrEP effectiveness hinges upon adherence, but levels of adherence vary and tend to be lower among Black individuals and youth. Adherence to daily PrEP does not need to be perfect to obtain benefit–in the iPrEx open-label extension, taking 2-3 doses/week was 84% efficacious (4+ was 100% efficacious)–and non-daily dosing strategies are also under investigation (event- and time-driven dosing). Beyond adherence, patterns of use are critically important. Oral PrEP is unlikely to be a life-long strategy for most, and evidence suggests that many YMSM discontinue PrEP (particularly Black and Latino YMSM), but most discontinuers report continued HIV risk behaviors. Further, studies are beginning to examine episodic PrEP use during discrete periods of highest HIV risk. Finally, risk compensation (i.e., decreased condom use after initiating PrEP) is a crucial component of PrEP effectiveness as it may maintain, or even increase, HIV transmission if adherence is not optimal. The goal of the current proposal is to characterize PrEP adherence across dosing strategies, describe patterns of use (continuous, episodic, discontinuation), and examine racial differences in adherence and patterns of use. We will embed novel mixed-methods research into RADAR, a diverse cohort of YMSM (N>1,200; age 16-29) assessed every 6 months (U01DA036939). We propose to add a daily diary study of PrEP users to characterize adherence and patterns of use, biomarkers of adherence to objectively measure PrEP coverage, and in-depth interviews with PrEP users to understand contextual influences on these issues. Aim 1: Describe PrEP adherence, dosing strategies, and usage patterns among YMSM. We will conduct a 3-month daily diary study with 120 YMSM PrEP users from RADAR to: a) characterize patterns of PrEP dosing strategies (daily, time-driven, event- driven), adherence, and usage patterns (continuous, episodic, discontinuation); b) Examine whether PrEP adherence or dosing strategies are associated with self-reported sexual risk behavior and STI infection; and c) describe racial differences in PrEP adherence, dosing strategies, and risk compensation. Aim 2: Assess associations between usage patterns and long- and short-term concentrations of PrEP in red blood cells. We will collect dried blood spot samples once per month during the diary study (3x) to assess concentrations of tenofovir-diphosphate and embtricitabine-triphosphate. Aim 3: Characterize YMSM perspectives on adherence, usage patterns, and risk compensation. We will conduct in-depth interviews with 60 YMSM diary study participants to understand individual, interpersonal, and structural influences on PrEP adherence and patterns of use, with an emphasis on understanding racial differences. Data from this study will inform the development of public health messaging and behavioral interventions to improve PrEP effectiveness among diverse YMSM.