A Social Network Approach to Improve HIV Prevention and Substance Use Treatment For People Who Use Drugs

This study includes finalization of the LINKED social network intervention to improve PrEP and MOUD uptake among people who inject drugs (PWID) in collaboration with an Expert Advisory Board and staff (N=16) at The Sidewalk Project (TSP), followed by a Hybrid Type II cluster randomized trial of the LINKED intervention (versus an equal-attention control) among N=372 people who inject drugs, with 6- and 12-month follow-up assessment of PrEP and MOUD uptake. The investigators will also evaluate implementation outcomes to inform future sustainable implementation of LINKED in harm reduction organizations.

Study Overview

• Status: Not yet recruiting
• Conditions: HIV Prevention; Substance Use
• Intervention / Treatment: Behavioral: LINKED; Behavioral: Group Intervention

• Study Type: Interventional
• Enrollment (Estimated): 398
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Suzan Walters, PhD; Phone Number: 951-443-6351; Email: Suzan.Walters@nyulangone.org

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90033
      • University of Southern California
      • Principal Investigator: Ricky Bluthenthal, PhD
  • Illinois
    • Chicago, Illinois, United States, 60637
      • The University of Chicago
      • Principal Investigator: Alida Bouris, PhD, MSW
  • New York
    • New York, New York, United States, 10016
      • NYU Langone Health
      • Principal Investigator: Suzan Walters, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Aim 1 - Virtual Focus Group

• Is 18 years or older
• Is a current TSP staff
• Is capable and willing to provide consent

Aim 2 - Intervention

• 18 years or older
• Spend majority of their time in the Los Angeles, CA area where recruited
• Able to complete surveys and group sessions in English
• Self-report to have injected drugs in the past 3 months
• Self-reported HIV negative serostatus
• Not currently on PrEP or MOUD
• Not pregnant
• If a network recruit: presents a valid recruitment coupon
• Is capable and willing to provide consent

Aim 3 - Virtual Focus Group/Surveys

• Is 18 years or older
• Is a current TSP staff
• Is capable and willing to provide consent

Exclusion Criteria:

Aims 1 and 3:

• Individuals who are not current TSP staff members will be excluded from participation.

Aim 2:

• Under age 18;
• Does not spend majority of time in the Los Angeles, CA area where recruited;
• Unable to complete surveys and groups sessions in English;
• Does not self-report injecting drugs in past 3 months;
• Self-reported HIV positive serostatus
• Currently on PrEP or MOUD
• Currently pregnant
• If a network recruit: does not present a valid recruitment coupon

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: LINKED Intervention; Participants randomized to the LINKED arm will receive a peer change agent intervention consisting of a 3-hour workshop divided into four learning and practice modules.	Behavioral: LINKED; LINKED is a theory-driven social network intervention (SNI) that leverages peer influence within the social networks of people who inject drugs (PWID) to disseminate information, encourage communication, and increase pre-exposure prophylaxis (PrEP) and medications for opioid use disorder (MOUD) uptake and persistence in harm reduction organization (HRO) settings.
Active Comparator: Equal-Attention Control; Participants randomized to the equal attention control group will receive a group intervention facilitated by trained study staff.	Behavioral: Group Intervention; Group intervention facilitated by trained study staff that supports critical thinking about what constitutes low, medium, and high risks for HIV and overdose.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of Participants with PrEP Uptake	Measured via filled PrEP prescription.	Month 6
Percentage of Participants with PrEP Uptake	Measured via filled PrEP prescription.	Month 12
Percentage of Participants with MOUD Uptake	Measured via filled MOUD prescription or buprenorphine, methadone, or naltrexone enrollment.	Month 6
Percentage of Participants with MOUD Uptake	Measured via filled MOUD prescription or buprenorphine, methadone, or naltrexone enrollment.	Month 12
Percentage of Participants with PrEP Adherence	Measured via urine immunoassays to test for oral PrEP.	Month 6
Percentage of Participants with PrEP Adherence	Measured via urine immunoassays to test for oral PrEP.	Month 12
Percentage of Participants with MOUD Adherence	Measured via urinalysis to test for metabolites for MOUD.	Month 6
Percentage of Participants with MOUD Adherence	Measured via urinalysis to test for metabolites for MOUD.	Month 12

Collaborators and Investigators

• Sponsor: NYU Langone Health
• Collaborators: National Institute on Drug Abuse (NIDA)
• Investigators: Principal Investigator: Suzan Walters, PhD, NYU Langone Health

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2027
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: February 9, 2026
• First Submitted That Met QC Criteria: February 9, 2026
• First Posted (Actual): February 13, 2026

Study Record Updates

• Last Update Posted (Actual): February 13, 2026
• Last Update Submitted That Met QC Criteria: February 9, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders
• Other Study ID Numbers: 25-01629

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The de-identified participant data from the final research dataset will be shared upon reasonable request beginning 9 to 36 months after publication or as required by a condition of awards or supporting agreements, provided the requesting investigator executes a data use agreement with NYU Langone Health. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's Data Sharing Strategy Board (DSSB). Requests should be directed to: Suzan.Walters@nyulangone.org. The protocol and statistical analysis plan will be posted on Clinicaltrials.gov only as required by federal regulation or supporting awards and agreements.
• IPD Sharing Time Frame: Beginning 9 months and ending 36 months following article publication or as required by a condition of awards and agreements supporting the research.
• IPD Sharing Access Criteria: The investigator who proposed to use the data will be granted access upon reasonable request. Requests should be directed to Suzan.Walters@nyulangone.org. To gain access, data requestors will need to sign a data access agreement. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's DSSB.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

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