Trial Outcomes & Findings for Understanding Effects of Cannabis Use and Abstinence on Neural Glutamate Homeostasis (NCT NCT05664763)
NCT ID: NCT05664763
Last Updated: 2025-08-19
Results Overview
Participants will undergo a Positron Emission Tomography (PET) scan to visualized mGluR5 availability in the regions of interest (ROIs): orbitofrontal cortex (OFC), anterior cingulate, ventromedial prefrontal cortex (vmPFC), dorsolateral prefrontal cortex (dlPFC), hippocampus, and amygdala. Only done at baseline for HC group.
TERMINATED
EARLY_PHASE1
6 participants
Baseline and Day 28
2025-08-19
Participant Flow
No healthy controls were enrolled.
Participant milestones
| Measure |
Cannabis Use Disorder
CUD participants participants undergo neuroimaging, cognitive testing, and EEG at baseline and following cannabis abstinence at 4 weeks follow-up. Participants will receive motivational enhancement and contingency management during the 4-week abstinence period.
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Healthy Control
Healthy control participants undergo neuroimaging, cognitive testing, and EEG at baseline.
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|---|---|---|
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Overall Study
STARTED
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6
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0
|
|
Overall Study
Only Attended One Visit
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3
|
0
|
|
Overall Study
Attended Both Visits
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3
|
0
|
|
Overall Study
Included in Analysis
|
2
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0
|
|
Overall Study
COMPLETED
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3
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0
|
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Overall Study
NOT COMPLETED
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3
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0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Understanding Effects of Cannabis Use and Abstinence on Neural Glutamate Homeostasis
Baseline characteristics by cohort
| Measure |
Cannabis Use Disorder
n=6 Participants
CUD participants participants undergo neuroimaging, cognitive testing, and EEG at baseline and following cannabis abstinence at 4 weeks follow-up. Participants will receive motivational enhancement and contingency management during the 4-week abstinence period.
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|---|---|
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Age, Continuous
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30.5 years
STANDARD_DEVIATION 6.95 • n=93 Participants
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Sex: Female, Male
Female
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4 Participants
n=93 Participants
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Sex: Female, Male
Male
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2 Participants
n=93 Participants
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Ethnicity (NIH/OMB)
Hispanic or Latino
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1 Participants
n=93 Participants
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Ethnicity (NIH/OMB)
Not Hispanic or Latino
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5 Participants
n=93 Participants
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Ethnicity (NIH/OMB)
Unknown or Not Reported
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0 Participants
n=93 Participants
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Race (NIH/OMB)
American Indian or Alaska Native
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0 Participants
n=93 Participants
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Race (NIH/OMB)
Asian
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0 Participants
n=93 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
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0 Participants
n=93 Participants
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Race (NIH/OMB)
Black or African American
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4 Participants
n=93 Participants
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Race (NIH/OMB)
White
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1 Participants
n=93 Participants
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|
Race (NIH/OMB)
More than one race
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1 Participants
n=93 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=93 Participants
|
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Region of Enrollment
United States
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6 participants
n=93 Participants
|
PRIMARY outcome
Timeframe: Baseline and Day 28Participants will undergo a Positron Emission Tomography (PET) scan to visualized mGluR5 availability in the regions of interest (ROIs): orbitofrontal cortex (OFC), anterior cingulate, ventromedial prefrontal cortex (vmPFC), dorsolateral prefrontal cortex (dlPFC), hippocampus, and amygdala. Only done at baseline for HC group.
Outcome measures
| Measure |
Cannabis Use Disorder
n=2 Participants
CUD participants participants undergo neuroimaging, cognitive testing, and EEG at baseline and following cannabis abstinence at 4 weeks follow-up. Participants will receive motivational enhancement and contingency management during the 4-week abstinence period.
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|---|---|
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Change in Metabotropic Glutamate Receptor 5 (mGluR5) Availability
Amygdala
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-2.218 ml/cm^3
Standard Deviation 8.07
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Change in Metabotropic Glutamate Receptor 5 (mGluR5) Availability
Anterior Cingulate
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-4.03 ml/cm^3
Standard Deviation 9.98
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Change in Metabotropic Glutamate Receptor 5 (mGluR5) Availability
Dorsolateral Prefrontal Cortex
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-3.94 ml/cm^3
Standard Deviation 8.97
|
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Change in Metabotropic Glutamate Receptor 5 (mGluR5) Availability
Hippocampus
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-2.946 ml/cm^3
Standard Deviation 7.21
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Change in Metabotropic Glutamate Receptor 5 (mGluR5) Availability
Orbitofrontal Cortex
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-5.2 ml/cm^3
Standard Deviation 10.78
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Change in Metabotropic Glutamate Receptor 5 (mGluR5) Availability
Ventromedial Prefrontal Cortex
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-4.33 ml/cm^3
Standard Deviation 9.97
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SECONDARY outcome
Timeframe: Baseline and Day 28Population: Due to limitations in the availability of trained staff, data for the secondary outcomes were not collected. The project was scaled down to assess only the primary outcome, as reported above. All available data from this project have been reported. Data collection and analysis for this measure will not be conducted in the future.
A battery of neuropsychological tests from the well-validated CogState Cognitive Battery are sensitive to detecting cognitive deficits in mood disorders, executive control and working memory. The entire battery takes approximately 30 minutes. Change in CUD group at baseline and day 28 compared to HC at baseline.
Outcome measures
Outcome data not reported
SECONDARY outcome
Timeframe: Baseline and Day 28Population: Due to limitations in the availability of trained staff, data for the secondary outcomes were not collected. The project was scaled down to assess only the primary outcome, as reported above. All available data from this project have been reported. Data collection and analysis for this measure will not be conducted in the future.
Theta band power and coherence will be assessed. EEG data are collected in three separate conditions. In the passive listening condition, subjects will passively listen to a list of 15 words (presented one at a time) six times in a row. In the memory encoding condition, subjects will be administered a list of 15 words played one at a time, five times, and will be told to try and remember the list and to repeat as many words as possible after each list. Twenty minutes after the end of the encoding phase, subjects will be asked to repeat as many words as they can from the original list of words. In the computerized recognition condition, subjects will hear words from the (1) original memorized list, (2) the distractor list, and (3) novel words not heard that day. Subjects will respond with a three-choice button box to indicate from which list each word originated. Change in CUD group at baseline and day 28 compared to HC at baseline.
Outcome measures
Outcome data not reported
Adverse Events
Cannabis Use Disorder
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place