THC + CBD and Memory Study

• ClinicalTrials.gov Identifier: NCT04855526
• Recruitment Status: Unknown
• First Posted: April 22, 2021
• Last Update Posted: January 6, 2022
• Sponsor: Hartford Hospital
• Collaborator: Yale University
• Information provided by (Responsible Party): Godfrey Pearlson, Hartford Hospital

Study Description

Brief Summary:

Memory deficits are one of the most consistently observed cognitive effects of marijuana use. There is evidence that some decrements attributable to the primary psychoactive ingredient, delta-9-tetrahydrocannabinol (THC), may be attenuated by cannabidiol (CBD). This study will help us learn more about the relationship between THC and CBD consumption with memory processes. A combination of MRI and neuropsychological tests (which are computer and paper/pencil tasks) will be used to measure the neurocognitive and behavioral impacts of THC and CBD use.

Condition or disease	Intervention/treatment	Phase
Marijuana Use; Cannabis Use; Cannabis Intoxication	Drug: High THC/No CBD Marihuana; Drug: High THC/High CBD Marihuana; Drug: No THC/No CBD Marihuana	Early Phase 1

Detailed Description:

With increased legalization and medicalization of marijuana (MJ), there is an urgent need to understand the acute effects of use. One of the most consistently observed cognitive outcomes associated with MJ use is memory dysfunction, which may have a substantial impact on daily life in individuals using MJ for recreational or medicinal purposes. Notably, there are numerous preparations of MJ with varying proportions of cannabinoids, which may differ in behavioral and cognitive effects. For instance, there is emerging evidence that acute administration of delta-9-tetrahydrocannabinol (THC), the main psychoactive constituent of MJ, hinders memory and reduces prefrontal and hippocampal functional magnetic resonance imaging (fMRI) activation, but cannabidiol (CBD) may mitigate some of these impairments. Given the role of glutamate in learning and memory, the investigators suggest that these effects may be subserved, in part, by glutamatergic mechanisms. The investigators will use magnetic resonance spectroscopy (MRS) to non-invasively measure glutamate in order to explore the neurochemical underpinnings of memory-related fMRI response changes following acute administration of THC and CBD in a randomized, double-blind, placebo-controlled, cross-over design. A total of 9 healthy participants ages 18-40 will be enrolled. Participants will first undergo one screening visit (~4 hours), comprising informed consent, assessment of health history, psychiatric diagnoses, cognitive function, and substance use history, and a structural MRI session. This will be followed by 3 separate MJ dose visits (~4 hours each), at which participants will complete neuroimaging after administration of one of 3 preparations of vaporized MJ in a randomized, counterbalanced, double-blinded fashion: 1) high THC and no CBD (THC), 2) high THC and high CBD (THC+CBD), and 3) no THC and no CBD (placebo MJ). As in the investigator's ongoing studies, bulk MJ plant material will be provided by the National Institute on Drug Abuse. MJ dose visits will comprise MJ administration, blood collection, MRS/fMRI scan, subjective reports, and a brief cognitive assessment.

Study Design

• Study Type: Interventional (Clinical Trial)
• Estimated Enrollment: 9 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
• Primary Purpose: Other
• Official Title: Effects of Marijuana on Memory-Related Neurochemistry and Neural Response
• Estimated Study Start Date: April 1, 2022
• Estimated Primary Completion Date: June 30, 2022
• Estimated Study Completion Date: June 30, 2022

Arms and Interventions

Arm	Intervention/treatment
Experimental: Occasional Users - High THC and High CBD Dose; People who smoke marijuana occasionally will be given a dose of high THC high CBD marijuana at the study visit	Drug: High THC/High CBD Marihuana; high THC (65 mg THC) and high CBD (50 mg CBD)
Experimental: Occasional Users - High THC and No CBD Dose; People who smoke marijuana occasionally will be given a dose of high THC and no CBD marijuana at the study visit	Drug: High THC/No CBD Marihuana; high THC (65 mg THC) and no CBD (0 mg CBD)
Experimental: Occasional Users - No THC and No CBD Dose; People who smoke marijuana occasionally will be given a dose of marijuana that contains no THC or CBD	Drug: No THC/No CBD Marihuana; no THC (0 mg THC) and no CBD (0 mg CBD); placebo drug

Outcome Measures

Primary Outcome Measures :

1. fMRI response [ Time Frame: approximately 1 hour following drug administration ]
   Blood oxygen level dependent functional magnetic resonance imaging (fMRI) response during the relational and item specific encoding task. fMRI response will be evaluated during the encoding phase (relational vs. item encoding), item recognition phase (hits vs. misses for item-specific encoding, and hits vs. misses for relational encoding), and associative recognition phase (hits vs. misses).
2. Glutamate [ Time Frame: approximately 1 hour following drug administration ]
   Magnetic resonance spectroscopy (MRS)-acquired glutamate containing compounds (Glx).

Secondary Outcome Measures :

1. HVLT-R performance [ Time Frame: Approximately 2.50 hours after drug administration ]
   The Hopkins Verbal Learning Test-Revised will ascertain verbal list learning and immediate and delayed recall (~15min); alternate forms have been validated, and the order of versions participants receive will be randomized
2. Performance on CHARLIE cognitive task [ Time Frame: Approximately 3.00 hours after drug administration ]
   This is a computer-based cognitive battery that administers the Digit Span and Letter/Number Sequencing Test (working memory) and the Digit Symbol Coding test (processing speed). It should take about 10 minutes to complete.
3. Blood THC and CBD concentration testing [ Time Frame: Immediately after drug administration (~0.25 hours after drug administration) ]
   A blood sample will be taken once per dose visit to assess the concentration of the following metabolites in ng/mL: delta-9-tetrahydrocannabinol, 11-hydroxy-tetrahydrocannabinol, 11-Nor-9-Carboxy-tetrahydrocannabinol (THCCOOH), tetrahydrocannabinol-Glucuronide, THCCOOH-Glucuronide, cannabinol (CBN), and cannabidiol (CBD).
4. Subjective effects on drug effects questionnaire [ Time Frame: Post drug administration at: 0.00 hours (immediately after); 1.0 hours; 2.0 hours; 3.0 hours ]
   This self-report will be used to assess subjective reports every 60 minutes throughout the dose visit days. These subjective ratings will be obtained using rapidly completed Visual Analog Scales (VASs) scored on a 0-100 scale. Items include: Do you feel a drug effect right now?, Are you high right now?, Do you dislike any of the effects you are feeling right now?, Do you like any of the effects you are feeling right now? and Would you like more of the drug you took, right now?

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 40 Years (Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

Inclusion Criteria:

• Right-handed
• Prior MJ users (has used MJ at least once in the past year, but no more than 1x/month in the past 12 months)
• Medically healthy (as determined by medical history and treatment)
• Adequate comprehension of English in order to complete study materials
• Acceptable birth control method for women (i.e., no copper IUD or any device that is not MRI safe)

Exclusion Criteria:

• Participant currently uses psychoactive medications or substances
• Psychiatric diagnoses (determined by DSM-V)
• Participant heavily or regularly uses MJ (more than 1x/month in the past year)
• Current or past substance dependence (including MJ)
• Positive urine toxicology screens
• Positive pregnancy screens
• MRI contraindications (e.g., heart pacemaker)

Contacts and Locations

Contacts

Contact: Chelsea N Meagher, BA; 860-545-7106; chelsea.meagher@hhchealth.org

Contact: Diana G King, BA; 860-545-7563; diana.king@hhchealth.org

Sponsors and Collaborators

Hartford Hospital

Yale University

Investigators

• Principal Investigator: Godfrey Pearlson, MD; Hartford Hospital - Olin Neuropsychiatry Research Center; Yale University
• Principal Investigator: Alecia Dager, PhD; Hartford Hospital - Olin Neuropsychiatry Research Center; Yale University
• Principal Investigator: Michael Stevens, PhD; Hartford Hospital - Olin Neuropsychiatry Research Center

More Information

• Responsible Party: Godfrey Pearlson, Founding Director Olin Neuropsychiatry Research Center; Professor Yale University, Hartford Hospital
• ClinicalTrials.gov Identifier: NCT04855526
• Other Study ID Numbers: R-HHC-2019-0137; 126663 ( Other Grant/Funding Number: Hartford Hospital )
• First Posted: April 22, 2021
• Last Update Posted: January 6, 2022
• Last Verified: January 2022

• Studies a U.S. FDA-regulated Drug Product: Yes
• Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Godfrey Pearlson, Hartford Hospital:

marijuana; cannabidiol; memory; THC; cannabis; intoxication; MRI; glutamate; MRS

Additional relevant MeSH terms:

Marijuana Abuse; Marijuana Use; Substance-Related Disorders; Chemically-Induced Disorders; Mental Disorders; Dronabinol; Hallucinogens; Physiological Effects of Drugs; Psychotropic Drugs; Analgesics, Non-Narcotic; Analgesics; Sensory System Agents; Peripheral Nervous System Agents; Cannabinoid Receptor Agonists; Cannabinoid Receptor Modulators; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists