Recruiting

Cannabis Abstinence

Sponsor:

Centre for Addiction and Mental Health

Code:

NCT04935619

Conditions

Cannabis Use

Major Depressive Disorder

Cognitive Impairment

Eligibility Criteria

Sex: All

Age: 18 - 55

Healthy Volunteers: Not accepted

Interventions

Contingency Reinforcement

Non-Contingency Reinforcement

Study Details

Brief summary:

The prevalence of major depressive disorder (MDD) is \~5.0%, and rates of co-occurring SUDs in these patients approach 40-50%. Specifically, rates of co-morbid cannabis use disorder (CUD) in patients with MDD are elevated 2-3 fold compared to 2.9% in the general population, and is associated with poorer treatment outcomes and impaired cognitive and psychosocial functioning in comparison to MDD patients without CUD. Most studies of cannabis use in MDD are cross-sectional in design, and therefore causal relationships are unclear. This study investigates the effects of cannabis abstinence over a 28-day period in patients with MDD with co-occurring CUD using a randomized controlled design, namely contingent reinforcement.

Conditions

Cannabis Use

Major Depressive Disorder

Cognitive Impairment

Study ID

NCT04935619

Start date

Jul 21, 2021

Status verified date

Feb, 2025

Completion date

Aug 31, 2027

Anticipated

Primary completion date

Jun 30, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 55

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • All participants must be between the ages 18-55
  • Meet SCID for DSM-5 diagnostic criteria for cannabis use disorder, moderate to severe
  • Meet SCID for DSM-5 diagnostic criteria for Major Depressive Disorder
  • Be an outpatient receiving a stable dose of antidepressant medication for at least three months (to ensure stability of depressive symptoms
  • Have a Hamilton Depression Rating Scale (HDRS-17) at baseline assessment in the range of 12-25..
  • Have a Full-Scale IQ ≥ 80 as determined by the WTAR
  • Be a non-treatment seeking cannabis user
  • Evidence of sufficient motivation and effort as measured by a Test of Memory Malingering (TOMM) score ≥ 45.

Exclusion Criteria:

  • Meets criteria for substance use disorder of alcohol or other illicit substances within the past 6 months (with the exception of cannabis, nicotine, or caffeine)
  • Positive urine screen for illicit substances other than cannabis, nicotine, or caffeine
  • Current suicidal or homicidal ideation
  • Psychotic disorder diagnosis (e.g. schizoaffective disorder, major depression with psychotic features) as determined by the SCID
  • Treatment seeking for cannabis use
  • Meet SCID for DSM-5 diagnostic criteria for Bipolar Disorder
  • Head Injury> 5 minutes LOC
  • Exceed upper and lower cut-offs on HSRD-17 (See Inclusion Criteria)

Study Design

Enrollment

52 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

other: Non-Contingency Reinforcement Group

Subjects assigned to the NCR group with self-reported abstinence verified by urinary THC-COOH level <20 ng/ml will not receive contingency monetary reinforcement at Day 28 of the study.

experimental: Contingency Reinforcement Group

Subjects assigned to the CR group with self-reported abstinence verified by urinary THC-COOH level <20 ng/ml will receive contingency monetary reinforcement at Day 28 of the study.

Interventions

Contingency Reinforcement

Subjects will be randomly assigned on a 1:1 ratio to either the Contingency Reinforcement or Non-Contingency Reinforcement Intervention prior to their in-person screening visit.

Non-Contingency Reinforcement

Subjects will be randomly assigned on a 1:1 ratio to either the Contingency Reinforcement or Non-Contingency Reinforcement Intervention prior to their in-person screening visit.

Primary outcome measure

  • Changes in Depressive Symptomology from Baseline to Week 4 [ Time Frame: [Time Frame: Weekly (Day 0, Day 7, Day 14, Day 21, Day 28)] ]
  • Changes in Anxious Symptomology from Baseline to Week 4 [ Time Frame: [Time Frame: Weekly (Day 0, Day 7, Day 14, Day 21, Day 28)] ]
  • Changes in Sleep Symptomology from Baseline to Week 4 [ Time Frame: [Time Frame: Weekly (Day 0, Day 7, Day 14, Day 21, Day 28)] ]
  • Changes in Anhedonia from Baseline to Week 4 [ Time Frame: [Time Frame: Weekly (Day 0, Day 7, Day 14, Day 21, Day 28)] ]

Central Contacts and Locations

Central contacts

Maryam Sorkhou, HBSc

4165358501maryam.sorkhou@mail.utoronto.ca

Locations

Centre for Addiction and Mental Health

Recruiting

Toronto, Ontario, Canada, M5T 1R8

Principal Investigator:

Tony P George, M.D.

More Information

Sponsor

Centre for Addiction and Mental Health

Last update posted

Feb 24, 2025

Last verified

Feb, 2025

Keywords

  • cannabis
  • substance abuse
  • depression
  • anxiety
  • contingency reinforcement

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Centre for Addiction and Mental Health on 2025-02-24.