Genetic Basis of the Risk and Consequences of Cannabis Exposure in Humans

September 1, 2026 updated by: Deepak C. D'Souza, Yale University
Cannabis is widely used worldwide and is associated with negative outcomes including cannabis use disorder (CanUD), psychosis, and cognitive impairment amongst others. Given the legalization of "recreational" and "medical" cannabis globally, the increasing availability of cannabis, the higher potency of cannabis, the availability of highly potent cannabinoid products, the commercialization of cannabis, and the rising rates of cannabis use, it is critical to understand how genetic factors influence 1) an individual's vulnerability for addiction and psychosis, 2) the response to cannabinoids, 3) the response to novel treatments for CanUD. CanUD is strongly genetically influenced; the investigators published the first CanUD genomewide association study (GWAS) with genomewide-significant results; however, the precise nature of the contribution of genetic factors in the development of CanUD is still not clear. Cannabis exposure has also been linked to a number of psychosis outcomes including schizophrenia (SCZ). SCZ is highly heritable and population-based and genetics studies both support a bidirectional genetic relationship between SCZ and CanUD. However, the precise contribution of genetic factors in the development of psychosis outcomes related to cannabis are not clear.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
215

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • Connecticut
      • West Haven, Connecticut, United States, 06516
        • Recruiting
        • West Haven Veterans Affairs Medical Center
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

-Ages 21-60 years old

Exclusion Criteria:

  • Major or unstable medical conditions based on history, the Structured Clinical Interview for DSM-5, collateral information, physical and laboratory examinations, ECG, and vital signs.
  • Cannabis naïve individuals
  • Positive pregnancy test

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Other
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Placebo Comparator: Placebo
Control: small amount of alcohol administered intravenously (quarter teaspoon), with no delta-9-THC, over 20 minutes.
Drug: Placebo
Control: Small amount of sterile 190 proof USP ethanol (1-2 mLs), with no THC, administered intravenously over 20 minutes.
Active Comparator: Delta-9-THC Very Low Dose
Active delta-9-THC administered intravenously over 20 minutes.
Drug: Delta-9-THC Very Low Dose
Active Delta-9-THC administered intravenously over 20 minutes.
Active Comparator: Delta-9-THC Medium Dose
Active delta-9-THC administered intravenously over 20 minutes.
Drug: Delta-9-THC Medium Dose
Active Delta-9-THC administered intravenously over 20 minutes.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Visual Analog Scale (VAS)
Time Frame: Measured at baseline, 20 minutes, 45 minutes, 90 minutes, 140 minutes, 165 minutes, 210 minutes, 270 minutes, and 360 minutes after the start of the initial THC/placebo drug infusion.
The VAS is a scale to document perceived reward. A higher score reflects a positive response.
Measured at baseline, 20 minutes, 45 minutes, 90 minutes, 140 minutes, 165 minutes, 210 minutes, 270 minutes, and 360 minutes after the start of the initial THC/placebo drug infusion.
Positive and Negative Symptom Scale (PANSS)
Time Frame: Measured at baseline, 45 minutes, 90 minutes, 165 minutes, 210 minutes, and 360 minutes after the start of the initial THC/placebo drug infusion.
The Positive and Negative Syndrome Scale is a 30-item scale to assess both the positive and negative symptom symptoms of schizophrenia. The range total score is 30-210. An improvement in symptoms is reflected by a lower score.
Measured at baseline, 45 minutes, 90 minutes, 165 minutes, 210 minutes, and 360 minutes after the start of the initial THC/placebo drug infusion.
Clinician Administered Dissociative Symptoms Scale (CADSS),
Time Frame: Measured at baseline, 45 minutes, 90 minutes, 165 minutes, 210 minutes, and 360 minutes after the start of the initial THC/placebo drug infusion.
Perceptual alterations will be measured using scales such as the Clinician Administered Dissociative Symptoms Scale (CADSS), a scale consisting of 19 self-report items and 8 clinician-rated items (0 = not at all, 4 = extremely) that we have shown to be sensitive to THC effects. The scale captures alterations in environmental/time/body perception, feelings of unreality, and memory impairment.
Measured at baseline, 45 minutes, 90 minutes, 165 minutes, 210 minutes, and 360 minutes after the start of the initial THC/placebo drug infusion.
CogState Battery
Time Frame: Measured at baseline, 45 minutes, and 165 minutes after the start of the initial THC/placebo drug infusion.
The CogState Battery measures cognition including verbal learning and recall and episodic memory.
Measured at baseline, 45 minutes, and 165 minutes after the start of the initial THC/placebo drug infusion.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Yale University

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Institute on Drug Abuse (NIDA)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Deepak D'Souza, MD, Yale University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
September 16, 2024

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 31, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 31, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 15, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 21, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 28, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 2, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 1, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2000036194
  • RO1 (Other Identifier: National Institute on Drug Abuse)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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