Exploring how CBD affects THC's psychoactive effects
Official title: Modulation of ∆9-tetrahydrocannabinol Acute Psychoactive Effects by Ranging Doses of Cannabidiol in Healthy, Occasional Cannabis Users: a Controlled, Triple Blind, Randomized, Cross-over Study
Run by Centre hospitalier de l'Université de Montréal (CHUM) · NCT06099379 · Data updated 2026-11-12
This study is testing how different amounts of CBD can change the effects of THC when people inhale them together.
Quick facts
| Phase | Phase1; Phase2 |
|---|---|
| Study type | Interventional |
| Ages | 21 Years to 49 Years |
| Sex | All |
| Enrollment | 100 (estimated) |
| Sponsor | Centre hospitalier de l'Université de Montréal (CHUM) Academic / other |
| Locations | 1 site (Montreal, Quebec) |
| Status | Recruiting |
| Started | June 27, 2024 |
| Main results expected | July 31, 2026 |
| Study ends | December 31, 2026 |
| Registry record updated | December 22, 2025 |
| Trial ID | NCT06099379 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are adults aged 21 to 49 who have used cannabis at least once and have limited recent use.
✕Probably not a fit
Patients who do not use cannabis or are outside the specified age range may not benefit from this study.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This study aims to investigate the modulation of THC's psychoactive effects by CBD at various ratios and doses. Participants will inhale different combinations of CBD and THC to assess their behavioral and pharmacological responses. The research seeks to fill gaps in understanding how CBD influences THC effects, which is crucial for public safety and informed cannabis use. By evaluating these interactions, the study hopes to provide insights that can guide regulatory bodies and improve cannabis consumption guidelines.
Why it matters
Potential benefit: If successful, this study could help patients and consumers make more informed choices about cannabis products, potentially enhancing safety and efficacy.
How similar studies have gone: While there is ongoing research into cannabinoid interactions, this specific approach to studying CBD's modulation of THC effects is relatively novel.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: 1. Between 21 and 49 years of age, inclusively; 2. Have used cannabis at least once in their lifetime and have used cannabis three days or less in the 30 days prior to enrollment; 3. Be able to provide a signed informed consent; 4. Willing to comply with study procedures and requirements as per protocol; 5. Have a forced expiratory volume in first second (FEV) less than or equal to 90 %; 6. Able to communicate and understand English or French language; 7. For female participants: a. No childbearing potential, defined as: i. postmenopausal (12 months of spontaneous amenorrhea and ≥ 45 years of age); or ii. Documented surgically sterilized (i.e., tubal ligation, hysterectomy, or bilateral oophorectomy); or b. For female of childbearing potential: i. Must have negative pregnancy test result at screening and at subsequent visits. ii. AND have no pregnancy plan while on the study iii. AND must agree to use a medically accepted method of birth control throughout the study. Exclusion criteria Participants will be excluded if any of the following criteria are met: 1. Any disabling medical condition, as assessed by medical history, physical exam, vital signs and/or laboratory assessments that, in the opinion of the study physician, precludes safe participation in the study or the ability to provide fully informed consent; 2. Severe psychiatric condition (history of schizophrenia, schizoaffective disorder or bipolar disorder; current acute psychosis, mania or current suicidality based on the Mini International Neuropsychiatric Interview); 3. Any other disabling, unstable or acute mental condition that, in the opinion of the study physician, precludes safe participation in the study or ability to provide fully informed consent; 4. Known chronic liver disease or aspartate transaminase/alanine transaminase (AST/ALT) two times higher than upper limit of normal values at screening visit; 5. Blood pressure higher than 130/80 mmHg; 6. Kidney disorders; 7. Bleeding disorders; 8. Current moderate or severe DSM-5 substance use disorder (except nicotine) according to SCID-V; 9. Currently pregnant, breastfeeding or planning to become pregnant either at screening or while enrolled in the study; 10. Pending legal action or other reason that, in the opinion of the study physician, might prevent study completion; 11. Use of medication within 7 days of experimental sessions; which, in the opinion of the Investigator, may interact with cannabis. 12. Participation in clinical studies or undergoing other investigational procedure involving cannabis or cannabinoids administration within 30 days prior to randomization. 13. Resting heart rate over 100 beats per minute. 14. Current body mass index (BMI) over 29.9 kg/m2. 15. Any clinically significant electrocardiogram abnormalities at screening visit.
Where it's running
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Centre de recherche du Centre Hospitalier Universitaire de Montréal
Montreal, Quebec, Canada Recruiting
Study contacts
- Principal investigator: Didier Jutras-Aswad, MD, MS — Crchum
- Study coordinator: Pamela Lachance, PhD
- Email: pamela.lachance-touchette.chum@ssss.gouv.qc.ca
- Phone: 514-890-8000
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.