Approach Bias Modification for the Treatment of Cannabis Use Disorder

Study Overview
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Brief Summary
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Effective and durable treatments for cannabis use disorder remain elusive. Given the increasing prevalence rates of cannabis use and CUD nationwide, investigation of novel treatments is warranted. Implicit cognitive processing is an emerging, and potentially critical therapeutic target. Cognitive models of addiction posit an override of explicit control-related cognitive processes by implicit reward-driven processes resulting from chronic drug exposure. One form of implicit cognitive processing is approach bias, or, the automatic tendency to approach rather than avoid drug cues, which has been identified for alcohol, nicotine, opioids, and cannabis. Cannabis approach bias predicts increased cannabis use, dependence severity, and cannabis-related problems among heavy cannabis users. Approach bias modification (ABM) is a novel treatment approach that seeks to reduce approach bias by attenuating the incentive-salience of drug cues, and subsequently, drug cue reactivity and drug use. ABM has been shown to reduce relapse rates in alcohol dependent adults by 10-13% at one-year follow-up, and dependence severity in nicotine dependent adults. Our pilot data suggests that ABM may also reduce cannabis craving and that gender may moderate the effect of ABM on cannabis sessions per day in non-treatment seeking adults with CUD. A recent fMRI study with alcohol-dependent adults found decreased mesolimbic activation in participants who received ABM compared to sham-control participants. ABM appears to target implicit reward-driven processes, and could be an effective adjunct to traditional psychosocial and/or future pharmacological interventions that target explicit control-related processes. Building on our promising feasibility data, the proposed K23 research study will examine the effects of ABM on cue-reactivity and cannabis outcomes in a four-session randomized, double-blind, sham-controlled pilot treatment trial. One-hundred and six (106) treatment-seeking adults with moderate to severe CUD will be randomized to receive either MET/CBT plus ABM or Motivational Enhancement Therapy/Cognitive Behavioral Therapy(MET/CBT) plus sham-ABM. An equal number of men and women will be recruited and randomization will be stratified by gender. ABM sessions will occur following each of the three weekly MET/CBT therapy sessions. Primary outcomes will include cannabis cue-reactivity and cannabis use.

Official Title
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Approach Bias Modification for the Treatment of Cannabis Use Disorder

Conditions
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Cannabis Use Disorder

Intervention / Treatment
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* Behavioral: Approach Bias Modification (ABM)
* Behavioral: Sham ABM
* Behavioral: Psychosocial therapy for cannabis use disorder.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be age 18-65 and must be able to provide informed consent. Meet DSM-5 criteria for current moderate to severe CUD (past 60 days). Identify cannabis as their primary substance of choice. Consent to remain abstinent from alcohol and cannabis for 12 hours immediately prior to study visits and other drugs of abuse (except nicotine) for three days prior (see Additional Instrumentation below for methods); by restricting cannabis and other substance use as proposed, participants should not be under the acute effects of cannabis or other substances. Exclusion Criteria: Evidence of, or a history of serious medical or neurological disease that may affect cognitive processing. History of, or current psychotic disorder, bipolar disorder, and attention-deficit hyperactivity disorder, or current untreated major depressive disorder as these may interfere with subjective measurements. Current use of psychotropic medications because these may affect subjective measurements (individuals taking antidepressants will be allowed). Current suicidal ideation. Individuals who endorse suicidal ideation will be seen by a psychologist or psychiatrist in the office and will be referred to treatment as necessary. Women who are pregnant, nursing or of childbearing potential and not practicing an effective means of birth control. Moderate to severe DSM-5 substance use disorder within the past 60 days (other than nicotine or cannabis).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Active ABM + CBT/MET<br>Participants in the Active ABM condition will receive approach bias modification (ABM) training sessions aimed at reducing cognitive bias for cannabis cues. All participants will receive MET/CBT therapy. | Behavioral: Approach Bias Modification (ABM)<br>* Approach bias modification (ABM) is a novel treatment that involves retraining the implicit action tendency to approach a drug cue by manipulating contingencies in a stimulus-response paradigm.<br>Behavioral: Psychosocial therapy for cannabis use disorder.<br>* All participants will receive psychosocial therapy for cannabis use disorder.<br>|
| Sham Comparator: Sham ABM + CBT/MET<br>Participants in the Sham ABM condition will undergo similar computerized tasks without the manipulation of response contingencies that target modification of approach bias. All participants will receive MET/CBT therapy. | Behavioral: Sham ABM<br>* Sham ABM involves similar computerized procedures that mimic the active experimental condition, but do not involve manipulation of response contingencies and thus it does not contain any active intervention.<br>Behavioral: Psychosocial therapy for cannabis use disorder.<br>* All participants will receive psychosocial therapy for cannabis use disorder.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in cannabis cue-reactivity | Using a cue-reactivity paradigm, we will evaluate the efficacy of approach bias modification on physiological (i.e. skin conductance) and subjective (i.e. cannabis craving) cue-reactivity. | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in percent days abstinent | Using self-report we will evaluate the efficacy of ABM on percent days abstinent. | 8 weeks | 
| Change in creatinine-adjusted cannabinoid levels | Using urine toxicology we will evaluate the efficacy of ABM on creatinine-adjusted cannabinoid levels. | 8 weeks |