The purpose of this trial is: * To investigate whether cannabidiol (CBD), compared to placebo, can reduce the severity of attenuated psychotic symptoms in individuals at clinical high risk for psychosis. * To confirm the safety of CBD in individuals at clinical high risk for psychosis. The trial is a randomised, double-blind, placebo-controlled, multi-centre, international clinical trial. Individuals meeting clinical high risk for psychosis criteria will be recruited for the trial intervention component of the trial. Participants are randomised to treatment with oral CBD 300mg (oral solution 100 mg/mL) twice daily, or a matching placebo, for 104 weeks. By using a battery of clinical outcome assessments, the trial will be able to assess several biomarkers to predict clinical outcomes and response to treatment with CBD. Participants will be invited to provide blood samples, stool samples, cerebrospinal fluid samples (if aged 18 years or over) and complete neuroimaging assessments. Individuals who are not found to have mental illness as defined by DSM-5 criteria will be recruited to a healthy control group, to validate the biomarker component of the trial. Additionally, a control group of healthy volunteers will be recruited who will not take the trial intervention to aid calibration between datasets from sites acquiring MRI data and to inform and validate any possible multivariate signature associated with the CHR-P state, course or outcome by understanding how these measures are different in controls. Healthy controls will also be used for secondary case-control comparisons. Healthy controls will undergo clinical and biomarker assessments only.
Age range
12 Years – 35 Years
Sex
ALL
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Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
ChaChange from baseline in attenuated positive psychotic symptoms (CAARMS P1-P4 positive symptom subscale score)
Timeframe: Baseline to Week 104