NCT04411225 · University of California, San Diego
Effects of Cannabidiol (CBD) Versus Placebo as an Adjunct to Treatment in Early Psychosis
What this study is about
This is an outpatient, single center, between-group, double blind, placebo controlled design. Approximately 120 adolescents and adult patients will be randomly assigned to either have their treatment augmented with Cannabidiol taken by mouth Solution (CBD) or with a matching CBD placebo for 8 weeks. The study will examine CBD as an augmentation strategy in early psychosis.
View original scientific description
This is an outpatient, single center, between-group, double blind, placebo controlled design. Approximately 120 adolescents and adult patients will be randomized to either have their treatment augmented with Cannabidiol Oral Solution (CBD) or with a matching CBD placebo for 8 weeks. The study will examine CBD as an augmentation strategy in early psychosis. It is hypothesized that CBD will improve symptoms, neurocognition, markers of inflammation and eating behaviors.
Interventions
DRUG
Cannabidiol oral solution
Both the active drug (cannabidiol) and placebo will be in oral solution.
Primary outcome measures
Positive and Negative Symptoms of Psychosis
Time frame: Week 7
Psychotic symptoms will be assessed with The Positive and negative psychotic syndrome scale (PANSS). This scale provides a summary score of all positive symptoms and all negative symptoms in participants who are already diagnosed with a psychotic disorder. The total score ranges from 30 to 210 with a higher score representing more symptoms.
Neurocognition
Time frame: week 7
A Global Cognition Score will be assessed with Measurement and Treatment Research in Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB) in all subjects.The Global Cognitive Score is a composite of the Z scores across the different cognitive domains in the MCCB. The range of scores is -1 to +1. Positive scores represent better cognitive functioning.
Prodromal Symptoms
Time frame: Week 7
The Scale of Prodromal Symptoms (SOPS) is part of the Structured Interview for Prodromal Syndromes (SIPS) diagnostic interview. This scale will be used to assess subsyndromal psychotic symptoms in participants who are diagnosed as Clinical High Risk for Psychosis. Positive and Negative Symptoms will be assessed as summary scores of all positive or negative items The minimum score on the SOPS total is 0 and Maximum is 24. A higher score represents more symptoms.
General Symptoms
Time frame: week 7
The Brief Psychiatric Rating Scale (BPRS) will be used as an assessment of overall symptom ratings with a total score in all subjects. The minimum score is 24 and maximum is 168. A higher score represents more symptoms.
Clinical Global Impression Scale (CGI-S)
Time frame: Week 7
The CGI-S will provide a global psychopathology score for all subjects. The Clinical Global Impression - Severity scale (CGI-S) is a 7-point scale that requires the clinician to rate the severity of the patient's illness at the time of assessment, relative to the clinician's past experience with patients who have the same diagnosis. A "1" is considered normal while a "7" is extremely ill.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- First episode psychosis (onset within the last 2 years) or attenuated psychosis syndrome (APS), stabilized with treatment for at least 8 weeks prior to initiating the trial consistent with the FDA-NIMH-MATRICS guidelines for clinical trial design for clinical enhancing drugs:
- Clinically stable and in a nonacute phase of their illness for at least 2 months, First episode psychosis participants will have been maintained on current antipsychotic for at least 6 weeks, with no change in antipsychotic dose for the previous 4 weeks while APS participants will be on the same treatment regimen (psychosocial or pharmacologic) for 4 weeks,
- Exhibit no more than moderate levels of positive symptoms (defined by ratings of ≤ 4) on PANSS items P1 (delusions), P2 (conceptual disorganization), P3 (hallucinatory behavior), P5 (grandiosity), P6 (suspiciousness), and G8 (unusual thought content),
- No more than a minimal level of depressive symptoms as assessed by the Calgary Dep
Where
- La Jolla, California
- San Diego, California
Collaborators
Center for Medicinal Cannabis Research
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jan 8, 2026 · Source of record for eligibility and locations