Does Cannabidiol Attenuate the Acute Effects of ∆9-tetrahydrocannabinol Intoxication in Individuals Diagnosed With Schizophrenia? A Double-blind, Randomised, Placebo-controlled Experimental Study

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

36 participants

Study Classification

INTERVENTIONAL

Study Start Date

2021-01-01

Study Completion Date

2023-07-07

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

This study will recruit schizophrenia patients who use cannabis recreationally. Each participant will attend the laboratory on three occasions: an initial visit to check that they are safe to join the study and two days of testing.

Participants will be administered, in a randomized order, a pre-treatment with either CBD (1000mg) orally or a matching placebo. On both experiments, participants will then inhale cannabis containing THC. The THC administration will follow a standardised inhalation procedure using a medical-grade vaporizer device.

Participants will complete a series of tasks measuring cognition, psychosis, anxiety and other subjective experiences.

The study will be carried out at the NIHR-Wellcome Trust Clinical Research Facility at King's College Hospital.

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Effects of Cannabidiol on Psychiatric Symptoms, Cognition, and Cannabis Consumption in Cannabis Users With Recent-Onset Psychosis

NCT03883360

Schizophrenia Spectrum Disorders Cannabis Use

WITHDRAWN PHASE2

Cannabidiol Treatment in Patients With Early Psychosis

NCT02504151

Schizophrenia Schizoaffective Disorder

COMPLETED PHASE2

Cannabidiol Treatment of Cognitive Dysfunction in Schizophrenia

NCT00588731

Schizophrenia Schizoaffective Disorder

COMPLETED PHASE2

Evaluation of the Antipsychotic Efficacy of Cannabidiol in Acute Schizophrenic Psychosis

NCT00628290

Schizophrenia

COMPLETED PHASE2

Effects of Cannabidiol (CBD) Versus Placebo as an Adjunct to Treatment in Early Psychosis

NCT04411225

Early Psychosis

RECRUITING PHASE3

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Schizophrenia Cannabis Use

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

QUADRUPLE

Participants Caregivers Investigators Outcome Assessors

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Placebo/THC

Oral placebo followed by inhalation of cannabis containing THC.

Group Type EXPERIMENTAL

Placebo

Intervention Type DRUG

Placebo

Delta-9-THC

Intervention Type DRUG

THC

CBD/THC

Oral CBD 1000mg followed by inhalation of cannabis containing THC.

Group Type EXPERIMENTAL

Cannabidiol

Intervention Type DRUG

CBD

Delta-9-THC

Intervention Type DRUG

THC

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Cannabidiol

CBD

Intervention Type DRUG

Placebo

Intervention Type DRUG

Delta-9-THC

THC

Intervention Type DRUG

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Age 18-65 years.
* Clinical diagnosis of schizophrenia (i.e. documented as such in the patient's clinical records and satisfying ICD-10 criteria for F20)
* Clinically stable for at least three months (since discharge from hospital, home treatment team, or prior clinical deterioration, and with agreement from the patient's responsible clinician)
* Regular (at least weekly) cannabis use for the past 3 months or more
* Evidence from either clinicians or from the patient that cannabis use exacerbates their symptoms or increases their risk of relapse
* Treatment with regular doses of antipsychotic medication for at least 1 month, confirmed by a blood test at the baseline visit, and with the participant agreeing to be maintained at a stable dose over the course of the experiment
* The participant agrees to abstain from cannabis use for at least 24hours prior to study visits
* The participant is willing to have an intravenous cannula inserted to collect blood samples on experimental visits
* Sufficiently fluent English
* Providing written informed consent

Exclusion Criteria

* Extreme cannabis use: participant is estimate to be using over 1gram of cannabis/day
* Dependence on alcohol or illicit substances other than cannabis as defined by ICD-10
* Pregnancy (current or planned) or breastfeeding
* Physical health disorder or another mental health disorder that the study psychiatrist judges may influence the patient's ability to tolerate the procedure, or that may alter the results of the study.
* Taken part in any drug study within the last 3 months or taking part in another study over the course of the trial
* Drug sensitivity/allergy to cannabis or Lorazepam
* Unlikely to be able to complete the study sessions for any reason, as judged by the study psychiatrist

Additional criteria which must be met on experimental visits:

* Negative alcohol breath test
* Negative urine drug screen (apart from cannabis and prescribed medication)
* Negative urine pregnancy test
* Stable mental state as judged by the study psychiatrist

Minimum Eligible Age

18 Years

Maximum Eligible Age

65 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No