The goal of this pilot clinical trial is to learn if an intervention that trains Gancheros (people who provide injection services in exchange for drugs or money) to conduct risk-reduction outreach could help lower risk for human immunodeficiency virus (HIV), hepatitis C virus (HCV) and overdose among migrant Puerto Rican people who inject drugs (PWID) in New York City. The main questions it aims to answer are:

• Can the Ganchero intervention be carried out successfully and will Gancheros and their clients like it?
• Could the Ganchero intervention help Puerto Rican PWID who are clients of Gancheros use sterile syringes and carry naloxone (a medication to reverse opioid overdoses) more often?

Gancheros who participate in the trial will be asked to attend a 6-session training on HIV, HCV, and overdose prevention and then to share key prevention messages and supplies (e.g., naloxone, sterile syringes and other injection equipment) with their clients during 4 months of outreach. The intervention will be carried out with Gancheros and their clients in two Bronx neighborhoods, one after the other, so the investigators can see if clients in the neighborhood that received the intervention first have better outcomes than clients in the neighborhood that did not yet receive the intervention.

The threat of human immunodeficiency virus (HIV) among people who inject drugs (PWID) in New York City (NYC) is not over. Multiple HIV outbreaks among PWID in rural and urban areas of the United States (US) have occurred recently, from 2015 in rural Indiana to 2018 in northeastern Massachusetts. PWID who are racial/ethnic minorities continue to be disproportionately infected with HIV. Among these, Puerto Rican (PR) PWID who started injecting drugs in Puerto Rico and continue to inject drugs in NYC remain highly vulnerable not only to HIV, but also to hepatitis C virus (HCV) and fatal opioid overdose. Analyses of two different cycles of the National HIV Behavioral Surveillance (NHBS) study conducted by the Centers for Disease Control and Prevention (CDC) in NYC found PR PWID, especially those who migrated from Puerto Rico, to be the most HIV-vulnerable ethnic group. In 2017, the US overdose mortality rate for US-born and Puerto Rico-born PR PWID exceeded the rate for Non-Hispanic Whites, and the same holds true in NYC. Recent research showed that PR PWID (both US- and Puerto Rico-born) have significantly higher prevalence of HCV than non-PR-PWID, and that Puerto Rico-born migrant PWID have the highest HCV prevalence (86%) of all three groups. Consequently, helping Puerto Rico-born PWID avoid HIV will help prevent HIV outbreaks in NYC. Lowering their HCV and overdose risk will help reduce overall HCV prevalence (67%) and overdose mortality rates (21.2 per 100,000) in NYC's PWID. Meeting these goals is urgent, as PWID migration from Puerto Rico to NYC is ongoing, as evidenced by their sizeable (≥25%) presence in NHBS studies in the past 15 years.

Risk behaviors of migrant PR PWID in the US are well documented. Compared to non-migrant PWID, migrants regularly engage in syringe- and cooker-sharing. In NYC, PR migrants mostly reside in the Bronx, the county with the largest numbers of PWID, overdose deaths, and new cases of HIV, and very high HCV prevalence in PWID. In a recent National Institute for Drug Abuse (NIDA)-funded ethnographic study (R03DA041892), the Principal Investigators identified normative practices learned while injecting drugs in Puerto Rico as critical influences on migrants' risks in NYC. These practices include: pervasive syringe-sharing after "cleaning" syringes by "air-blowing and water-rinsing"; regular sharing and trading of heavily used cookers which are highly valued for their concentrated drug residue; and low rates of naloxone carriage despite frequent overdoses.

Grounded in a multi-level ecosocial framework, the proposed intervention will directly target these practices by leveraging a key migrant PWID-role in NYC, the Ganchero: an "injection doctor" who exchanges injection expertise for drugs or money. Because migrant PWID regularly require expert injection services due to collapsed veins, Gancheros are central network members well-positioned to promote positive health change. This is aligned with social network diffusion theory, which underlies effective HIV prevention interventions that harness peer influence by relying on PWID to disseminate risk-reduction messages in their networks. PR migrant PWID are highly networked, and a peer-driven intervention relying on their network ties promises to yield sustainable health behavior change. The investigators will develop and conduct an initial evaluation of a Ganchero risk-reduction intervention for Puerto Rico-born PWID that is effective, culturally appropriate, credible, and sustainable.

First, a multi-method, iterative process that will incorporate input from Gancheros and their migrant clients will be used to develop the intervention: a training curriculum and outreach protocol for Gancheros. Building on specific intervention recommendations developed in consultation with a multiple-stakeholder Intervention Advisory Board and endorsed by focus groups of migrant PWID in the investigators' prior study, the intervention will empower Gancheros to promote and model consistent sterile syringe use and naloxone carriage with their clients and in their PWID networks. Targeting two Bronx neighborhoods with high proportions of PR migrants and non-overlapping PWID networks, the investigators will then conduct a pilot clinical trial to evaluate the feasibility, acceptability, and preliminary effectiveness of this innovative intervention.

Aim 1. Engage Gancheros (total n=4) and clients (total n=20) from both target neighborhoods in a series of semi-structured interviews and focus groups to develop a risk-reduction intervention comprised of a training curriculum and outreach protocol for Gancheros to implement with their regular clients in real-world settings.

Aim 2. Conduct a pilot clinical trial using a wait-list control design with 10 Gancheros and 60 clients across the two target neighborhoods to evaluate the intervention's feasibility (assessed via Ganchero and client participation rates), acceptability (assessed by Ganchero and client Visual Analog Scale [VAS] ratings and qualitative feedback) and preliminary effectiveness in increasing clients' rates of sterile syringe use (primary effectiveness outcome) and naloxone carriage (secondary effectiveness outcome).

Structured assessments to measure these outcomes will be supplemented with data from Gancheros' Weekly Outreach Reports and systematic ethnographic observations of Gancheros deploying intervention strategies in the field to assess fidelity of implementation, barriers encountered, and any pragmatic adaptations made in response to barriers, to inform future refinement of the intervention and its implementation strategy.

Impact: A Ganchero-led intervention may help prevent HIV outbreaks among PWID in NYC and mitigate the HCV and overdose syndemic among the highly vulnerable Puerto Rico-born PWID in NYC. Results will inform a larger hybrid effectiveness-implementation trial to evaluate a refined intervention for migrant PR PWID in NYC and other urban areas in the US with significant numbers of at-risk migrants.

Two distinct groups of participants with different eligibility criteria will be enrolled: (1) Gancheros (n=10, 5/neighborhood); and (2) Gancheros' clients (n=60, 30/neighborhood).

1. Ganchero participants:

   • Inclusion Criteria:

     • A migrant person who injects drugs (PWID) from Puerto Rico living in one of 2 pre-selected neighborhoods in the Bronx, New York City (NYC)
     • Past experience providing Ganchero services in Puerto Rico
     • Currently provides Ganchero services to ≥10 clients/day
     • Speaks Spanish or English

   • Exclusion Criteria:

     • Planned travel away from NYC for 2 weeks or longer over the next 24 months
     • Inability to comprehend trial information or provide informed consent (e.g., due to intoxication)

2. Client participants:

   • Inclusion Criteria:

     • A migrant PWID from Puerto Rico living in one of 2 pre-selected neighborhoods in the Bronx, NYC
     • Referred to the study by a participating Ganchero
     • Used the services of their nominating Ganchero at least once/week for the past 90 days
     • Speaks Spanish or English

   • Exclusion Criteria:

     • Inability to comprehend trial information or provide informed consent (e.g., due to intoxication)