PrEP Seguro: Antiretroviral-based HIV Prevention Among Men at High Risk in Mexico

The objective of this R34 application is to prepare for testing innovative user-centered ways to promote PrEP adherence at scale. Our central hypothesis is that adherence to PrEP can be improved among MSW if PrEP is provided for free along with highly-tailored conditional economic incentives (CEI). The specific aims are: Aim 1: To refine the design of PrEP adherence intervention with user-centered conditional economic incentives to maximize sustained adherence behaviors through a user-responsive computerized survey (n=200). We incorporate quantitatively identified preferences for CEIs through a user- responsive computerized survey. We use conjoint analysis to understand preferences for CEI intervention components and how CEIs should be integrated into an optimal combination package to be tested in Aim 2. Aim 2: Measure the extent to which a user-centered CEI intervention can help MSW increase their adherence to free PrEP in a randomized controlled pilot (n=100). Among MSW who accept to take free PrEP, and return at month 1 for a second pill bottle, we will randomize n=100 MSW to either: standard of care (SoC: information, prescription, free PrEP) or CEI (SoC + incentives contingent on sufficiently-high adherence to PrEP). We will assess the primary outcome (biomarker of adherence using scalp hair analysis) at months 3 and 6, as well as secondary outcomes: clinic attendance/retention, medication possession ratio, self-reported PrEP use, and sexual behavioral disinhibition (number of partners, condom use, incident STI). Aim 3: Estimate the preliminary cost-effectiveness of incentives for PrEP adherence to maximize future policy and practice relevance of this promising intervention strategy. Our working hypothesis is that conditional economic incentives for PrEP adherence will be cost-effective in terms of cost per fully- adherent month on PrEP, cost per HIV infection averted, and cost per disability-adjusted life year saved when compared to controls not receiving the conditional incentives. The expected outcome of this R34 is a demonstration that is feasible to implement user-centered CEIs in this context, as well as preliminary efficacy and cost-effectiveness data. The project will have positive impact because it is a critical step toward scaled-up implementation of PrEP in this highly-at-risk population of MSWs in Mexico, with implications for other concentrated epidemics among MSW worldwide.

Study Overview

• Status: Completed
• Conditions: HIV Infections
• Intervention / Treatment: Behavioral: Conditional Economic Incentive (CEI)

• Study Type: Interventional
• Enrollment (Actual): 310
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Mexico
  • DF
    • Mexico City, DF, Mexico
      • National Institute of Public Health (INSP) / Clinica Condesa

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Male at birth and self-identifies as male at the time of enrollment
• At least 18 years of age
• Has tested negative for HIV in the past month
• Demonstrates high risk of HIV acquisition defined as having had sex with penetration (oral or anal) with at least 8 male partners in past six months
• Has exchanged or accepted money, drugs or gifts in exchange for sex on at least 8 occasions in the past month
• Willing and capable of providing blood and scalp hair samples for assessments
• Willing and able to provide written informed consent
• Have successfully initiated PrEP and are returning for their second bottle of PrEP pills
• Able to provide a home address or personal telephone number, or able to provide two personal contacts who will be able to know the patient's whereabouts during the study period

Exclusion Criteria

• Under 18 years of age
• Unable to give informed consent due to severe mental or physical illness/substance intoxication at baseline visit
• Presents with severe adverse reactions to PrEP
• The subject will be excluded from the study at his own request for any reason since participation is voluntary

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CEI Group; CEI Group will receive the standard of care (information, prescription, free PrEP) and economic incentives contingent on sufficiently-high adherence to PrEP.	Behavioral: Conditional Economic Incentive (CEI); If hair testing shows that a participant has taken PrEP pills about 5-7 times in the previous week, he will receive a grade "A"; if he has taken PrEP pills about 3-4 times in the previous week he will receive a grade "B"; and if he has taken PrEP pills only 2 times or less, he will receive a grade "C". For those in the CEI group, if participant gets an A, he receives two additional prizes; if he gets a B, he receives one additional prize; and if he gets a C, he receives no additional prizes.
No Intervention: SOC Group; SOC Group will receive the standard of care only (information, prescription, free PrEP.)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ARV Hair Concentrations	Level of ARV (TDF/FTC) in scalp hair samples	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinic attendance/retention	This is a measure of retention in care. As each participant finishes his 6-month study period, retention will be determined by number of quarterly care visits completed.	6 months
Medication adherence	Medication Possession Ratio (MPR) is defined as the number of dispensed pills divided by the number of days between visits which will be derived from pharmacy refill records	6 months
Questionnaire to Assess Self-reported PrEP Use	Self report adherence to assess for change in adherence.	6 months
Reduction in HIV and STI incidence relative to control group	Male sex worker participants will be tested at baseline and 6-month follow-up for HIV and syphilis. Incidence rates for all infections at 6-month follow-up will be compared between the conditional economic incentive (CEI) group and the standard of care (SOC) group.	6 months
Reduction in number of unprotected sex acts relative to control group	Male sex worker participants will be assessed at baseline and 6-month follow-up using self-report measures of frequency of protected and unprotected sex acts with clients. Changes in frequency at 6-month follow-up will be compared between the conditional economic incentive (CEI) group and the standard of care (SOC) group.	6 months

Collaborators and Investigators

• Sponsor: Brown University
• Collaborators: National Institute of Mental Health (NIMH); University of California, San Francisco; Mexican National Institute of Public Health; Consorcio de Investigación sobre VIH/SIDA/TB (CISIDAT).
• Investigators: Principal Investigator: Omar Galarraga, PhD, Brown University

Publications and helpful links

General Publications

• Salinas-Rodriguez A, Sosa-Rubi SG, Chivardi C, Rodriguez-Franco R, Gandhi M, Mayer KH, Operario D, Gras-Allain N, Vargas-Guadarrama G, Galarraga O. Preferences for Conditional Economic Incentives to Improve Pre-exposure Prophylaxis Adherence: A Discrete Choice Experiment Among Male Sex Workers in Mexico. AIDS Behav. 2022 Mar;26(3):833-842. doi: 10.1007/s10461-021-03443-1. Epub 2021 Aug 27.

Study record dates

Study Major Dates

• Study Start (Actual): May 15, 2019
• Primary Completion (Actual): August 30, 2021
• Study Completion (Actual): August 30, 2021

Study Registration Dates

• First Submitted: August 10, 2018
• First Submitted That Met QC Criteria: September 14, 2018
• First Posted (Actual): September 18, 2018

Study Record Updates

• Last Update Posted (Actual): July 27, 2023
• Last Update Submitted That Met QC Criteria: July 25, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: adherence; PrEP; Cost-effectiveness; HIV Prevention; MSM; Anti-Retroviral Agents; Biological Markers; Behavioral Economics; AIDS prevention
• Additional Relevant MeSH Terms: RNA Virus Infections; Virus Diseases; Infections; Blood-Borne Infections; Communicable Diseases; Sexually Transmitted Diseases, Viral; Sexually Transmitted Diseases; Lentivirus Infections; Retroviridae Infections; Immunologic Deficiency Syndromes; Immune System Diseases; Urogenital Diseases; Genital Diseases; HIV Infections
• Other Study ID Numbers: 1R34MH114664-01 (U.S. NIH Grant/Contract); 5R34MH114664-02 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Materials generated under this project will be disseminated according to University and NIH policies regarding data sharing. Aggregate-level data collected in this collaboration will ultimately be available for public use. Opportunities for secondary analyses will be available following completion of the three-year project and publication of the main study findings. These findings will be available to the public through scientific meetings and peer-reviewed journals, as well as through a structured policy dissemination process.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No