Using psilocybin to help treat cannabis use disorder

An 8-week Phase 2 Clinical Trial to Evaluate the Safety, Tolerability and Efficacy of Psilocybin-assisted-psychotherapy in Adults With Cannabis Use Disorder: A Proof-of-Concept Study

This study is testing whether using psilocybin along with therapy can help people reduce their cannabis use.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 16 (estimated)
• Ages: 18 Years to 65 Years
• Sex: All
• Sponsor: McMaster University (Academic / other)
• Locations: 1 site (Hamilton, Ontario)
• Trial ID: NCT06225232 on ClinicalTrials.gov

What this trial studies

This study explores the use of psilocybin, a psychedelic compound, in combination with Motivational Enhancement Therapy (MET) to treat individuals with Cannabis Use Disorder (CUD). Participants will receive two doses of psilocybin over an 8-week period while engaging in psychotherapy aimed at reducing their cannabis use. The study will assess the feasibility, safety, tolerability, and potential therapeutic effects of this approach. By investigating this novel treatment, the study aims to address the lack of effective pharmacological and psychological interventions for CUD.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 to 65 who have a moderate to severe diagnosis of cannabis use disorder and wish to reduce or stop their cannabis use.

Not a fit: Patients who are not seeking to reduce or stop their cannabis use or those with severe medical conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new therapeutic option for individuals struggling with cannabis use disorder.

How similar studies have performed: Other studies have shown promising results using psilocybin for treating substance use disorders, suggesting potential success for this approach.

Eligibility criteria

Inclusion Criteria:

1. Signed Informed Consent Form.
2. Able to show documentation of identity.
3. Fluent in speaking and reading English and able to complete rating scales and assessments.
4. Between the ages of 18 to 65.
5. At Screening, meet criteria for CUD diagnosis of at least moderate severity as per the MINI Plus
6. Expressed a wish to reduce or stop cannabis use.
7. Medically healthy based on physician review of CBC, electrolytes, liver function test, kidney function tests and ECG.
8. Has a stable residence for the duration of the study.
9. Agree to comply with the protocol requirements set out by the study.
10. Consent to providing regular check-ins and follow-up regarding any medical conditions, procedures and adverse events.
11. If of child-bearing potential, female participants must agree to use an adequate birth control method (IUD, injected or implanted hormonal methods, abstinence, vasectomy of the partner/partners, or double barrier contraception i.e. condoms plus diaphragm, or diaphragm plus spermicide) for the duration of the study. Male participants should agree to using condoms with spermicide throughout the trial in addition to the use of an adequate contraceptive by their partner of childbearing potential.
12. Following discharge from the dosing sessions, agree to have another individual accompany them home from the study site and stay with them overnight.

Exclusion Criteria:

1. Meet DSM-5 criteria for lifetime history of bipolar disorder, schizophrenia, or other psychotic disorders, personality disorders, delirium, dementia and amnesic and other cognitive disorders, or are in a current agitated state.
2. Have first-degree biological relatives (parents or full siblings) with past or present history of schizophrenia, bipolar disorder and any other psychosis.
3. Meet DSM-5 criteria for panic disorder or seizure disorders.
4. Meet DSM-5 criteria for dependence of any substance other than cannabis or tobacco in the past 6 months.
5. Positive urine drug screen for substances tested with the exception of cannabis
6. History of serotonergic psychedelic use in the past year and over 5 times of lifetime use (psilocybin, LSD, Ayahuasca, mescaline, DMT).
7. Current treatment with psychotropic agents including stimulants, anti-psychotic agents, benzodiazepines and tri-cyclic anti-depressants. Concurrent treatment with Selective Serotonin Reuptake Inhibitors and Serotonin Noradrenalin Reuptake Inhibitors will be allowed, provided the dose has been stable for 4 weeks and remains stable during the study.
8. History of cardiovascular diseases or uncontrolled hypertension that is not successfully treated or any other medical condition that might pose a risk to the participant in the opinion of the study physician.
9. Are receiving concurrent psychotherapy for CUD.
10. Are reasonably judged to present a serious suicide risk as determined by Columbia Suicide Severity Rating Scale or expressed homicide risk, who have enacted suicidal behaviors within 6 months prior to intake, or w ho are likely to require psychiatric hospitalization during the study.
11. Participants of childbearing potential with a positive pregnancy test at screening or prior to dosing sessions, or are pregnant, breast feeding, and who are not using an acceptable means of birth control for the duration of the study.
12. Are unable to fully understand the potential risks and benefits of the study and give informed consent.
13. Are currently or planning on participating in other interventional clinical trials during this study.

Where this trial is running

Hamilton, Ontario

• MacAnxiety Research Centre — Hamilton, Ontario, Canada (Recruiting)

Study contacts

• Study coordinator: Maryam Rahat, Ph.D Candiate

Conditions Cannabis Use Disorder, Moderate; Cannabis Use Disorder, Severe; Cannabis Use Disorder; Psilocybin; Motivational Enhancement Therapy