CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

1115 Accuracy of PrEP Adherence Measures Among Transwomen and Young MSM in Latin America: ImPrEP Study Thiago S Torres 1 , Mayara Secco Torres da Silva 1 , Carolina Coutinho 1 , Pedro Leite 1 , Ronaldo Moreira 1 , Brenda Hoagland 1 , Juan V. Guanira 2 , Marcos Benedetti 1 , Hamid Vega 3 , Sergio Bautista 4 , Carlos Caceres 2 , Peter L. Anderson 5 , Beatriz Grinsztejn 1 , Valdilea Veloso 1 , for the ImPrEP Study Group 1 Instituto Nacional de Infectologia Evandro Chagas, Rio de Janeiro, Brazil, 2 Universidad Peruana Cayetano Heredia, Lima, Peru, 3 Instituto Nacional de Psiquiatria Ramon de la Fuente Muñz, Mexico City, Mexico, 4 Instituto Nacional de Salud Pública, Mexico City, Mexico, 5 University of Colorado, Aurora, CO, USA Background: HIV incidence is high among young men who have sex with men (YMSM) and transgender women (TGW). PrEP is a key strategy to reduce new HIV infections, and monitoring PrEP adherence is essential to guide implementation programs. We aimed to assess the accuracy of indirect PrEP adherence measures with drug concentrations in dried blood spots (DBS) among YMSM and TGW enrolled in the ImPrEP study. Methods: ImPrEP was an implementation project offering same-day oral PrEP for 9509 MSM/TGW in Brazil, Mexico, and Peru (Feb/2018-Jun/2021), with follow-up visits scheduled 4 weeks post-enrolment and quarterly thereafter, that included YMSM aged 18-24 years and TGW (all ages) who collected at least one DBS during follow-up. We compared two indirect adherence measures with DBS: medication possession ratio (MPR) (ratio between tablets dispensed in prior visit and days between the two visits) and self-reported information (single-question at each visit; 30-days recall). We used generalized estimating equations and area under the curve (AUC) to assess the accuracy of each indirect measure with protective drug DBS levels (TFV-DP ≥ 550 fmol/punch [week 4] and ≥ 800 fmol/punch [other weeks]), and the DeLong test to compare the curves. We calculated optimal cut-off points for discriminating protective drug levels based on Youden index and their respective sensitivity, specificity, negative (NPV) and positive (PPV) predictive values. Results: We included 4274 DBS samples from 2096 participants (week 4: 1905[44.6%], week 28: 1170[27.4%], week 52: 745[17.4%], week 76: 254[5.9%], week 100: 135[3.1%], week 124: 65[1.5%]). Overall, 1692 (80.7%) participants were MSM and 404 (19.3%) TGW; most were aged 18-24 years (1802; 86.0%), non-white (1582; 75.5%), and had ≥12 years of education (1374; 65.5%). Of all DBS samples, 2871(67.2%) had protective drug levels. AUC was 0.75(95%CI:0.74 0.77) for MPR and 0.76(95%CI:0.74–0.78) for self-report adherence (Table), with no difference between adherence assessment methods' curves (p>0.38). Calculated cut-off points for MPR and self-reported adherence were 97.0% and 93.3%, respectively. Conclusion: Self-reported adherence and MPR adequately discriminated protective levels of PrEP among key populations in Latin America at different time points during the study follow-up. These measures are low-cost, easy to implement, and allow for immediate action to support PrEP adherence at health service level and ultimately contribute to monitoring PrEP programs.

for the US in 2018 and 2022 overall, by gender, by race/ethnicity, and by age groups. Differences in median days on PrEP per year were assessed by gender, race/ethnicity, and age. To assess the potential impact of 2-1-1 PrEP dosing on median days of PrEP use, we compared data from 2018 (before CDC recommendation of 2-1-1 dosing) to data from 2022. Results: We evaluated data from 225,180 PrEP users in 2018, and 459,984 PrEP users in 2022. In 2022, the mean number of days covered by dispensed PrEP prescriptions among PrEP users was 187 (SD: 129.8; Figure). Mean days was lower among female (median 123 days) than male (median 192 days) users (P<0.01). Among PrEP users with race/ethnicity data, mean days of use were higher for White non-Hispanic (NH) (255 days) than for Hispanic (239 days) or Black NH (231 days) users (p<0.01 for each comparison). Older users had more days covered by PrEP than younger users (<16 years: 126 days; 16-29 years: 159 days; >30 years: 201 days; p<0.01 for comparisons between <16 years and other groups). A comparison of overall data for 2018 (182 days) versus 2022 (187 days) did not suggest that the USPHS 2021 inclusion of 2-1-1 PrEP in PrEP guidelines was associated with fewer days of coverage. Conclusion: PrEP programs are often evaluated by enumerating people who used PrEP at any time during a year; our data indicate that there are significant differences in PrEP coverage during a year's time, and that an annual use indicator might mask inequities in PrEP protection, with women, Black NH and Hispanic people, and younger people having fewer dispensed days of coverage. Assessments of days of PrEP coverage should be included in assessments potential impact of PrEP and to address and monitor PrEP equity.

Poster Abstracts

1117 Out-of-Pocket Payments for PrEP Ancillary Services Among US Commercially-Insured Persons, 2017-2021 Ya-Lin A Huang , Weiming Zhu , Sloane A. Bowman, Karen W. Hoover Centers for Disease Control and Prevention, Atlanta, GA, USA

Background: In June 2019, HIV preexposure prophylaxis (PrEP) received a grade A recommendation from the U.S. Preventive Services Task Force (USPSTF). Under the Affordable Care Act, private health plans and Medicaid expansion programs must cover the costs of all PrEP services without any patient cost sharing starting in January 2021, including PrEP medications and ancillary services such as clinical visits and laboratory testing. The objective of this study was to monitor trends in out-of-pocket (OOP) payments for PrEP ancillary services from 2017−2021 using a large commercial claims database. Methods: We analyzed data from the Merative™ MarketScan® Commercial Database that contains adjudicated medical claims. Using a validated algorithm, we identified persons aged ≥18 years prescribed PrEP from 2017−2021 and restricted the sample to those continuously enrolled in their plans for at least 6 months. We extracted all medical claims submitted for PrEP services within 1 week before each PrEP prescription using Current Procedural Terminology codes. We analyzed only fee-for-service claims and computed mean annual total and OOP (sum of copayment, deductible, and other coinsurance amounts) payments for each service. We also summed each service's total and OOP payments for combined amounts. All payments were inflated to 2021 U.S. dollars using the medical Consumer Price Index. Results: Between 2017−2021, we identified 127,055 adults prescribed PrEP. In 2021, PrEP users paid an average out-of-pocket cost of $34.60 for evaluation and management, $4.67 for preventive counseling, $3.08 for HIV testing, $2.98 for hepatitis B testing, $2.87 for hepatitis C testing, $1.30 for syphilis testing, $9.85 for gonorrhea testing, $10.42 for chlamydia testing, $1.91 for creatinine testing, and $2.84 for lipid testing. For most laboratory testing, the proportion of persons paying zero OOP payment increased over time, and more than 70% paid

1116 Inequities in PrEP Annualized Pill-Day Coverage: United States, 2018-2022

Patrick S Sullivan 1 , Eric Hall 2 , Heather Bradley 1 , Travis H. Sanchez 1 , Elizabeth S. Russell 3 1 Emory University, Atlanta, GA, USA, 2 Oregon Health and Sciences University, Portland, OR, USA, 3 Merck Research Laboratories, Rahway, NJ, USA Background: Pre-exposure prophylaxis (PrEP) is highly effective to reduce risk of HIV infection, but the population-level impact of PrEP depends on the proportion of people with PrEP indications who use it and how long they stay on it (persistence). Methods: We used previously reported methods and commercial pharmacy data to identify PrEP users and the duration of PrEP use calculating by dates of all prescriptions and number of pills dispensed in a year (pill-days per year). PrEP users include all patients who, at any point during the year, filled a prescription for Emtricitabine-Tenofovir Disoproxil Fumarate, Emtricitabine Tenofovir Alafenamide Fumarate, and/or Cabotegravir, but were not on any other antiretroviral medications. We calculated mean length of PrEP use

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