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CompletedNCT03189810rTMSCANSZUpdated Sep 5, 2023

Effects of Repetitive Transcranial Magnetic Stimulation (rTMS) on Cannabis Use and Cognitive Outcomes in Schizophrenia

An interventional study of Repetitive Transcranial Magnetic Stimulation (rTMS) and Sham Repetitive Transcranial Magnetic Stimulation (rTMS) in Repetitive Transcranial Magnetic Stimulation (rTMS), Schizophrenia and Cannabis Use Disorder, sponsored by Centre for Addiction and Mental Health. Completed at 1 site in Canada. Open to participants aged 18 Years to 55 Years. Per ClinicalTrials.gov, last updated 2023-09-05.

Sponsored by Centre for Addiction and Mental Health · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
24
Allocation
Randomized
Ages
18 Years to 55 Years
Sex
All
01

Study summary

The high prevalence of cannabis and other substance use disorders are a major barrier to recovery in people with schizophrenia. Moreover, schizophrenia patients have significant deficits in cognitive function, which may be exacerbated by cannabis use. Complicating these problems is the lack of evidence-based treatments for co-morbid cannabis use disorders (CUDs) in schizophrenia; there are no established pharmacotherapies. Therefore, this study is investigating the effects of high-frequency (20Hz) repetitive transcranial magnetic stimulation (rTMS) on cannabis use disorder and cognitive function in patients with co-morbid schizophrenia/schizoaffective disorder. The proposed study would be the first randomized, double-blind, sham controlled trial of rTMS in patients with schizophrenia and co-morbid CUD. A total of N=40 schizophrenia smokers with co-morbid cannabis use disorder will be assigned to either active rTMS (N=20) or sham rTMS (N=20) as a treatment regimen of 5X/week treatment for four consecutive weeks. All participants will receive weekly behavioral therapy for 4 weeks. The investigators predict that active rTMS will be well-tolerated and superior to sham rTMS for the treatment of CUD in schizophrenia.

02

Conditions studied

  • Repetitive Transcranial Magnetic Stimulation (rTMS)
  • Schizophrenia
  • Cannabis Use Disorder
  • Cognition

Keywords

  • Sham Repetitive Transcranial Magnetic Stimulation (rTMS)
  • Schizophrenia
  • Cannabis Use Disorder
  • Cognitive Function
03

In context

Marijuana Abuse

517 studies on the registry are indexed under Marijuana Abuse; 114 are open to participants now.

This study's enrollment of 24 is below the median of 60 across 421 interventional studies indexed under Marijuana Abuse.

Browse Marijuana Abuse studies →

Lead sponsor

Centre for Addiction and Mental Health is the lead sponsor of 327 studies on the registry; 51 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 55 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  1. Male (80%) or Female (20%);
  2. Age 18-55;
  3. Meet the Diagnostic and Statistical Manual of Mental Disorders version 5 (DSM-5) criteria for Schizophrenia (SZ) or schizoaffective disorder and cannabis use disorder with physiological dependence;
  4. Full scale intelligence quotient (IQ) ≥ 80 determined through the Wechsler Test of Adult Reading (WTAR);
  5. Non-smokers OR cigarette smokers as confirmed with Fragerstrom Test for Nicotine Dependence (FTND) score of 5 or higher, self reported smoking of at lest 5 cigarettes per day (measured by the Timeline Follow Back), and verified by a Smokerlyzer test, cut-off as 10 ppm.

Exclusion criteria

Exclusion Criteria:

  1. DSM-5 diagnoses of alcohol, substance or polyuse substance use disorder in the past 6 months (other than cannabis/caffeine or nicotine);
  2. Currently active suicidal ideation or self-harm (suicidal or non-suicidal) as assessed by the Structured Clinical Interview for DSM-5 (SCID-5);
  3. Head injury resulting in loss of consciousness (>5 minutes) and hospitalization;
  4. Major neurological or medical illness including seizure disorder or syncope;
  5. Metallic implants;
  6. History of rTMS treatment;
  7. Pregnancy.
05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
24 participants (actual)

Study arms

  • Experimental
    Active rTMS (20Hz)

    Active rTMS administered with the MagProX100/R30 stimulator equipped with the B65 active coil for dorsolateral prefrontal cortex (DLPFC) stimulator (MagVenture, Farum, Denmark).The randomization order will be determined by a project scientist from Temerty. While the primary aim of this study is not to treat individuals with cannabis dependence, it is imperative that participants attend weekly study visits in an attempt to achieve end of study (Day 28) cannabis abstinence.

    Device: Repetitive Transcranial Magnetic Stimulation (rTMS) · Behavioral: Weekly Counselling Session

  • Sham comparator
    Sham rTMS

    Sham rTMS administered with the MagProX100/R30 stimulator equipped with the B65 placebo coil for DLPFC stimulator (MagVenture, Farum, Denmark). The randomization order will be determined by a project scientist from Temerty. While the primary aim of this study is not to treat individuals with cannabis dependence, it is imperative that participants attend weekly study visits in an attempt to achieve end of study (Day 28) cannabis abstinence.

    Device: Sham Repetitive Transcranial Magnetic Stimulation (rTMS) · Behavioral: Weekly Counselling Session

Interventions

  • DeviceRepetitive Transcranial Magnetic Stimulation (rTMS)

    On Day 1, the resting motor threshold (RMT) will be determined according to previous published methods \[Cardenas-Morales et al. 2013\] and the rTMS will be delivered at an intensity of 90% of the participant's RMT. rTMS will be administered at 20 Hz (25 trains, 30 pulses per train, 30 second intertrain interval).

  • DeviceSham Repetitive Transcranial Magnetic Stimulation (rTMS)

    On Day 1, the resting motor threshold (RMT) will be determined according to previous published methods \[Cardenas-Morales et al. 2013\] and the Sham rTMS will be delivered at an intensity of 90% of the participant's RMT. rTMS will be administered at 20 Hz with the B65 placebo coil (25 trains, 30 pulses per train, 30 second intertrain interval).

  • BehavioralWeekly Counselling Session

    In order to support participants in their abstinence plan, individual weekly sessions of supportive counselling will be administered over the course of the study on 1 time per week over 4 weeks (28 days of abstinence).

06

What researchers measure

Primary outcomes

  1. The effects of active versus sham rTMS directed to DLPFC on cannabis abstinence in cannabis-dependent patients with schizophrenia as assessed by urine screens for changes in Tetrahydrocannabinol (THC) content.

    Urine samples will be collected weekly during the abstinence period and tested by study personnel using the Semi-Quantitative THC Pre-Dosage Test (NarcoCheck®, Villejuif, France).

    Time frame: Weekly (Day 0, Day 7, Day 14, Day 21, Day 28) and at 8 weeks (Follow-up Day 56)

  2. The effects of active versus sham rTMS directed to DLPFC on cannabis abstinence in cannabis-dependent patients with schizophrenia as assessed by urine screens for changes in Tetrahydrocannabinol (THC) content.

    Urine samples at Day 28 and Follow-Up (Day 56) will be sent to CAMH's clinical laboratory for gas chromatography/mass spectrometry (GC/MS) analysis to obtain quantitative THC-COOH and creatinine concentrations. Thus abstinence will also be assessed with combined quantitative urinalysis (\<50 ng/ml) and TLFB assessment.

    Time frame: Up to 4 weeks (Day 28) and 8 weeks (Follow-Up Day 56)

Secondary outcomes

  1. The effects of active (20 Hz) versus sham rTMS on change in cognitive function in cannabis dependent patients with schizophrenia as assessed by a cognitive battery administered at Baseline and at Day 28.

    The cognitive battery (Day 28) will include the primary outcome of verbal memory (assessed by HVLT) and will be compared to baseline (Day 1) performance. Cortical inhibition will also be assessed and compared between Day 1 and Day 28 performance.

    Time frame: Up to 4 weeks (Day 28) and 8 weeks (Follow-Up Day 56)

Other outcomes

  1. The effects of active (20 Hz) versus sham rTMS on change in cannabis craving in cannabis-dependent patients with schizophrenia as assessed by the Marijuana Craving Questionnaire (MCQ).

    MCQ will be assessed over time, specifically at Day 1 compared to Day 28.

    Time frame: Up to 4 weeks (Day 28) and 8 weeks (Follow-Up Day 56)

  2. The effects of active (20 Hz) versus sham rTMS on change in cannabis withdrawal in cannabis-dependent patients with schizophrenia as assessed by the Marijuana Withdrawal Checklist (MWC).

    MWC will be assessed over time, specifically at Day 1 compared to Day 28.

    Time frame: Up to 4 weeks (Day 28) and 8 weeks (Follow-Up Day 56)

  3. The effects of active (20 Hz) versus sham rTMS on psychotic symptoms in cannabis-dependent patients with schizophrenia as assessed by the Calgary Depression Scale for Schizophrenia (CDSS).

    CDSS scores will be compared over time, specifically Day 1 compared to Day 28. The depressive subscales within the PANSS will also be compared with the CDSS final score.

    Time frame: Up to 4 weeks (Day 28) and 8 weeks (Follow-Up Day 56)

  4. The effects of active (20 Hz) versus sham rTMS on psychotic symptoms in cannabis-dependent patients with schizophrenia as assessed by the Positive and Negative Syndrome Scale (PANSS).

    PANSS will be compared over time, specifically Day 1 compared to Day 28. The depressive subscales within the PANSS will also be compared with the CDSS final score.

    Time frame: Up to 4 weeks (Day 28) and 8 weeks (Follow-Up Day 56)

07

Study locations

1 site
  • Centre for Addiction and Mental Health
    Toronto, Ontario M6J1H4, Canada
08

References and documents

Publications

  • Johnstone S, Lowe DJE, Kozak-Bidzinski K, Sanches M, Castle DJ, Rabin JS, Rabin RA, George TP. Neurocognitive moderation of repetitive transcranial magnetic stimulation (rTMS) effects on cannabis use in schizophrenia: a preliminary analysis. Schizophrenia (Heidelb). 2022 Nov 17;8(1):99. doi: 10.1038/s41537-022-00303-2. PubMed 36384966 ↗

Individual participant data

Plan to share: No

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 5, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03189810
Lead sponsor
Centre for Addiction and Mental Health
Responsible party
Tony George (Principal Investigator, Centre for Addiction and Mental Health) — Principal investigator
First posted
Jun 16, 2017
Start date
Jun 1, 2017
Primary completion
Jun 30, 2021
Completion
Jun 30, 2021
Last update
Sep 5, 2023

Study contacts

Tony P George, MD, FRCPC
principal investigator · Centre for Addiction and Mental Health

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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