Cannabis THC Potency, Metabolism, and Cognitive Impairment in Young Adults

NCT06077292 | Suspended

• 1 other identifier: 23-39581
• Study Type: interventional
• Target: 110
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this interventional study is to determine the impact of high potency THC product use on cognitive function of young adults aged 21-25. The main question it aims to answer is: will cannabis users who switch to less potent THC products demonstrate improved cognitive function compared to baseline? Other questions this study aims to answer include:

• Can researchers accurately assess THC consumption among frequent cannabis users?
• Can researchers effectively incentivize cannabis users to use less potent THC products?
• Do genetic variations in THC metabolism impact urinary THC excretion?
• Do genetic variations in THC metabolism impact cognitive performance in cannabis users?
• Are quantitative urinary THC values predictive of cognitive impairment?
• How can researchers use research findings to inform harm reduction practices for people who use cannabis? Participants will submit blood and urine samples and be incentivized to use less potent THC products.

Conditions

THC; Cannabis Use; Marijuana Use; Cognitive Impairment; THC Vaping

Keywords

Cannabis; Marijuana; High Potency THC; Dabs; Wax; Young Adult; Youth

Outcome Measures

Primary Outcomes (7)

• Change in Rapid Visual Information Processing Score

  Cognitive performance will be assessed using the CANTAB, a computer-based cognitive assessment system. Participants in this study will complete a battery of seven neuropsychological tests. CANTAB is administered to subjects using a touch screen computer and is language- and culture- independent. Participants scores at 5 weeks will be compared to their baseline scores. The Rapid Visual Information Processing test takes 9 minutes to complete and is scored on a scale of 0-54, with a higher score indicative of better cognitive performance.

  Baseline and 5 weeks

• Change in Paired Associates Learning score

  Cognitive performance will be assessed using the CANTAB, a computer-based cognitive assessment system. Participants in this study will complete a battery of seven neuropsychological tests. CANTAB is administered to subjects using a touch screen computer and is language- and culture- independent. Participants scores at 5 weeks will be compared to their baseline scores. The Paired Associates Learning test takes 8 minutes to complete and is scored on a scale of 0-100%, with a higher percentage indicative of better cognitive performance.

  Baseline and 5 weeks

• Change in Delayed Matching-to-Sample Score

  Cognitive performance will be assessed using the CANTAB, a computer-based cognitive assessment system. Participants in this study will complete a battery of seven neuropsychological tests. CANTAB is administered to subjects using a touch screen computer and is language- and culture- independent. Participants scores at 5 weeks will be compared to their baseline scores. The Delayed Matching-to-Sample test takes 7 minutes to complete and is scored on a scale of 0-100%, with a higher percentage indicative of better cognitive performance.

  Baseline and 5 weeks

• Change in Verbal Recognition Memory score

  Cognitive performance will be assessed using the CANTAB, a computer-based cognitive assessment system. Participants in this study will complete a battery of seven neuropsychological tests. CANTAB is administered to subjects using a touch screen computer and is language- and culture- independent. Participants scores at 5 weeks will be compared to their baseline scores. The Verbal Recognition Memory test takes 6 minutes to complete and is scored on a scale of 0-36, with a higher score indicative of better cognitive performance

  Baseline and 5 weeks

• Change in Spatial Working Memory score

  Cognitive performance will be assessed using the CANTAB, a computer-based cognitive assessment system. Participants in this study will complete a battery of seven neuropsychological tests. CANTAB is administered to subjects using a touch screen computer and is language- and culture- independent. Participants scores at 5 weeks will be compared to their baseline scores. The Spatial Working Memory test takes 4 minutes to complete and is scored on a scale of 0-306, with a lower score indicative of fewer errors and better cognitive performance.

  Baseline and 5 weeks

• Change in One-Touch Stockings of Cambridge score

  Cognitive performance will be assessed using the CANTAB, a computer-based cognitive assessment system. Participants in this study will complete a battery of seven neuropsychological tests. CANTAB is administered to subjects using a touch screen computer and is language- and culture- independent. Participants scores at 5 weeks will be compared to their baseline scores. The One-Touch Stockings of Cambridge test takes 10 minutes to complete and scores are based on the time it takes for a participant to solve 20 problems. Shorter time to solve a problem is indicative of better cognitive performance.

  Baseline and 5 weeks

• Change in Stop Signal Task score

  Cognitive performance will be assessed using the CANTAB, a computer-based cognitive assessment system. Participants in this study will complete a battery of seven neuropsychological tests. CANTAB is administered to subjects using a touch screen computer and is language- and culture- independent. Participants scores at 5 weeks will be compared to their baseline scores. The Stop Signal Task test takes 14 minutes to complete and is scored on a scale of 1-1000 milliseconds, with a shorter time indicative of better cognitive performance.

  Baseline and 5 weeks

Secondary Outcomes (6)

• Baseline Urinary THC Excretion

  Baseline

• Week 1 Urinary THC Excretion

  7-10 days after study enrollment.

• Week 2 Urinary THC Excretion

  14-17 days after study enrollment.

• Week 3 Urinary THC Excretion

  21-24 days after study enrollment.

• Week 4 Urinary THC Excretion

  28-30 days after study enrollment.

Other Outcomes (24)

• Urinary THC Excretion in CYP2C9*3 carriers

  Baseline

• Cognitive Performance in CYP2C9*3 carriers

  Baseline

• Change in Cannabis Use Disorder Identification Identification Test (CUDIT) score

  Baseline and 5 weeks

Study Arms (2)

15% THC Potency Reduction Group

EXPERIMENTAL

Participants will be incentivized to use THC products that are at least 15% less potent than baseline

Behavioral: 15% THC Potency Reduction

35% THC Potency Reduction Group

EXPERIMENTAL

Participants will be incentivized to use THC products that are at least 35% less potent than baseline

Behavioral: 35% THC Potency Reduction

Interventions

35% THC Potency Reduction BEHAVIORAL

Participants will be incentivized to use THC products that are at least 35% less potent than baseline

35% THC Potency Reduction Group

15% THC Potency Reduction BEHAVIORAL

Participants will be incentivized to use THC products that are at least 15% less potent than baseline

15% THC Potency Reduction Group

Eligibility Criteria

• Age: 21 Years - 25 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Between the ages of 21-25
• Resides in San Francisco
• Self-report cannabis concentrate use as their primary method of cannabis use
• Self-report using cannabis daily or almost daily (i.e., at least 6 out of 7 days during each of the last 4 weeks)
• Self-report only purchasing cannabis from regulated retail stores in California.

You may not qualify if:

• Pregnant
• Regularly uses other drugs (other than nicotine)

Sponsors & Collaborators

• Advocates for Human Potential: collaborator
• University of California, San Francisco: lead

Study Sites (1)

University of California San Francisco

San Francisco, California, 94143, United States

Location

Related Publications (6)

• Sachse-Seeboth C, Pfeil J, Sehrt D, Meineke I, Tzvetkov M, Bruns E, Poser W, Vormfelde SV, Brockmoller J. Interindividual variation in the pharmacokinetics of Delta9-tetrahydrocannabinol as related to genetic polymorphisms in CYP2C9. Clin Pharmacol Ther. 2009 Mar;85(3):273-6. doi: 10.1038/clpt.2008.213. Epub 2008 Nov 12.

  PMID: 19005461 BACKGROUND

• Murray RM, Quigley H, Quattrone D, Englund A, Di Forti M. Traditional marijuana, high-potency cannabis and synthetic cannabinoids: increasing risk for psychosis. World Psychiatry. 2016 Oct;15(3):195-204. doi: 10.1002/wps.20341.

  PMID: 27717258 BACKGROUND

• Ramaekers JG, Kauert G, van Ruitenbeek P, Theunissen EL, Schneider E, Moeller MR. High-potency marijuana impairs executive function and inhibitory motor control. Neuropsychopharmacology. 2006 Oct;31(10):2296-303. doi: 10.1038/sj.npp.1301068. Epub 2006 Mar 29.

  PMID: 16572123 BACKGROUND

• D'Souza DC, Ganesh S, Cortes-Briones J, Campbell MH, Emmanuel MK. Characterizing psychosis-relevant phenomena and cognitive function in a unique population with isolated, chronic and very heavy cannabis exposure. Psychol Med. 2020 Oct;50(14):2452-2459. doi: 10.1017/S0033291719002721. Epub 2019 Oct 16.

  PMID: 31615592 BACKGROUND

• Bidwell LC, Martin-Willett R, Karoly HC. Advancing the science on cannabis concentrates and behavioural health. Drug Alcohol Rev. 2021 Sep;40(6):900-913. doi: 10.1111/dar.13281. Epub 2021 Mar 30.

  PMID: 33783029 BACKGROUND

• Bourque J, Potvin S. Cannabis and Cognitive Functioning: From Acute to Residual Effects, From Randomized Controlled Trials to Prospective Designs. Front Psychiatry. 2021 Jun 10;12:596601. doi: 10.3389/fpsyt.2021.596601. eCollection 2021.

  PMID: 34177633 BACKGROUND

MeSH Terms

Conditions

Marijuana Use; Cognitive Dysfunction; Vaping; Marijuana Abuse

Condition Hierarchy (Ancestors)

Behavior; Substance-Related Disorders; Mental Disorders; Cognition Disorders; Neurocognitive Disorders; Smoking; Chemically-Induced Disorders

Study Officials

• Veronika Mesheriakova, MD

  University of California, San Francisco

  PRINCIPAL INVESTIGATOR

• Michael Sofis, PhD

  Cannabis Public Policy Consulting

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: INVESTIGATOR
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 4, 2023
• First Posted: October 11, 2023
• Study Start: March 17, 2025
• Primary Completion: March 14, 2026
• Study Completion (Estimated): December 14, 2026
• Last Updated: April 13, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)