Harm Reduction With Pharmacotherapy (HaRP)

University of Washington logo

University of Washington

Status and phase

Phase 2


Alcohol Use Disorder


Behavioral: HRC
Drug: XR-NTX
Other: Placebo

Study type


Funder types



1R01AA022309-01 (U.S. NIH Grant/Contract)

Details and patient eligibility


The goal of this study is to test the efficacy of extended-release naltrexone and harm reduction counseling in reducing alcohol-related harm among homeless people with alcohol dependence.

Full description

Homelessness and alcohol dependence are commonly co-occurring and serious public health issues. Unfortunately, abstinence-based alcohol treatment approaches are minimally effective in engaging and successfully treating homeless individuals with alcohol dependence. There have therefore been calls for more flexible and client-centered approaches tailored to this population's needs. Innovative, low-barrier approaches (e.g., Housing First and alcohol management programs) have been applied with this population and are efficacious in reducing alcohol use and related problems as well as utilization of publicly funded services and associated costs. Such approaches have been referred to as harm-reduction interventions because they focus on reducing alcohol-related harm for affected individuals and their communities without requiring a commitment to abstinence-based goals. Although psychosocial, harm-reduction approaches are beginning to proliferate for this population, there are few pharmacological counterparts to support and enhance these efforts. One medication that could address this treatment gap is extended-release naltrexone (XR-NTX; marketed as Vivitrol®). XR-NTX is a 30-day, extended release formulation of the opioid receptor antagonist, naltrexone, and is administered monthly via gluteal intramuscular injection. The proposed Phase II study features a four-arm RCT (N=300) designed to test the efficacy of XR-NTX as a pharmacological adjunct to existing psychosocial harm-reduction services provided by community agencies to homeless people with alcohol dependence. The proposed study will include a 24-week follow-up and will test the relative efficacy of 3 active treatment combinations-1) XR-NTX+harm reduction counseling, 2) placebo+harm reduction counseling and 3) harm reduction counseling only (HRC)-compared to the services as usual (TAU) that all participants receive from community agencies. This proposed design will allow us to dismantle active treatment components and thereby detect potential "placebo effects" of both the administration of an injection and attention from a medical professional. In this study, there are three primary specific aims. First, we will test the relative efficacy of XR-NTX, placebo and HRC compared to TAU in decreasing alcohol quantity, frequency and alcohol-related problems. Second, we will test hypothesized mediators of the intervention effects. Specifically, we hypothesize that the active treatments will precipitate increases in motivation to change and decreases in craving, which, in turn, will mediate the active treatment effects on alcohol outcomes. Finally, we will test treatment effects on publicly funded service costs (i.e., emergency medical services, ER visits, hospital admissions, and county jail). It is hypothesized that XR-NTX, placebo and HRC groups will show greater decreases in publicly funded service costs than the TAU group.


308 patients




21 to 65 years old


No Healthy Volunteers

Inclusion criteria

  • being a registered client at one of the named partnering sites
  • being at least 21 years of age (for legal reasons)
  • agreeing to use an adequate form of birth control (if female and in childbearing years) fulfilling criteria for current alcohol dependence according to DSM-IV-TR criteria as determined by the SCID-I/P

Exclusion criteria

  • refusal or inability to consent to participation in research
  • constituting a risk to safety and security of other clients or staff
  • known sensitivity or allergy to naltrexone/XR-NTX
  • current treatment with naltrexone/XR-NTX
  • being pregnant or nursing
  • suicide attempts within the past year
  • renal insufficiency/serum creatinine level > 1.5
  • current opioid dependence according to the DSM-IV-TR criteria
  • liver transaminases (AST, ALT) > 5 times the upper limit of normal (ULN)
  • clinical diagnosis of decompensated liver disease

Trial design

Primary purpose




Interventional model

Parallel Assignment


Quadruple Blind

308 participants in 4 patient groups, including a placebo group

No Intervention group
Assessment-only control condition
Active Comparator group
Harm reduction counseling, which entails provision of feedback and support of harm reduction goals and safer drinking provided at one-month intervals over a 3-month period.
Behavioral: HRC
Experimental group
3 doses of active medication (380 mg injection/month) + Harm reduction counseling at one-month intervals over three months.
Drug: XR-NTX
Behavioral: HRC
Placebo Comparator group
3 doses of placebo + harm reduction counseling at one-month intervals over a three-month period
Other: Placebo
Behavioral: HRC

Trial documents

Trial contacts and locations



Data sourced from clinicaltrials.gov

Clinical trials

Find clinical trialsTrials by location


© Copyright 2024 Veeva Systems