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NCT Number: NCT02926859

Enhancing Recovery in Early Schizophrenia

Current antipsychotic treatments of schizophrenia are only partially effective, and their use is often associated with serious side effects. Cannabidiol is a natural counterpart of the psychoactive component of marijuana, delta-9- tetrahydrocannabinol and has no psychotomimetic or addictive properties. In a controlled clinical trial of cannabidiol versus amisulpride in acute paranoid schizophrenia we showed a statistically significant clinical improvement in all symptoms clusters of schizophrenia compared to baseline with either treatment. Cannabidiol displayed a significantly superior side-effect profile in particular regarding prolactin elevation, extrapyramidal symptoms and weight gain. The favorable side-effect profile and potentially novel mechanism of action identify this molecule as a potential antipsychotic. However, long-term safety and efficacy data is still lacking. This study is to evaluate the efficacy and safety of the novel compound cannabidiol in the maintenance treatment of schizophrenia in comparison to placebo as an add-on to an established treatment with either amisulpride, aripiprazole, olanzapine, quetiapine or risperidone, in a 12-months, double-blind, parallel-group, randomized, placebo-controlled clinical trial. Thereby, relevant data on cannabidiol's antipsychotic potential will be gained.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Conditions

Schizophrenia Mental Disorders Schizophrenia Spectrum and Other Psychotic Disorders

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Dept. of Psychiatry and Psychotherapy, Charité, Campus Charité-Mitte, Berlin, B, Germany

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Informed consent given by the subject
  • DSM-IV-TR diagnosis of schizophrenic psychosis (295.10-30, 295.90)
  • First documented diagnosis of schizophrenia must not be no older than seven years.
  • Patients must receive a stable dose of amisulpride, aripiprazole, olanzapine, quetiapine or risperidone (TAU: treatment as usual) at least 4 weeks prior to inclusion in the study to ensure that the maximal effect of the previous medication has been received.
  • Initial PANSS total score of ≤ 75 at baseline.
  • proper contraception in female patients of childbearing potential
  • body mass index between 18 and 40.

Exclusion criteria

  • Lack of accountability
  • positive urine drug-screening for illicit drugs at screening (except cannabinoids and benzodiazepines)
  • serious suicidal risk at screening visit
  • other relevant interferences of axis 1 according to diagnostic evaluation (MINI) including residual forms of schizophrenia.
  • other relevant neurological or other medical disorders
  • pregnancy or lactation.

Treatment and study plan

Cannabidiol as add-on

Drug

Cannabidiol capsules 2x200 mg twice a day as add-on to individualized pharmacological treatment with either amisulpride, aripiprazole, olanzapine, quetiapine or risperidone over 26 weeks

Placebo as add-on

Drug

Placebo capsules 2x200 mg twice a day as add-on to individualized pharmacological treatment with either amisulpride, aripiprazole, olanzapine, quetiapine or risperidone over 26 weeks

Primary outcomes

  1. All-cause discontinuation

    Time frame: within 12 month

Secondary outcomes

  1. Improvement in Psychopathology assessed by PANSS

    Time frame: 6, 9 and 12 month

    Positive and Negative Syndrome Scale (PANSS)

  2. Improvement in Psychopathology assessed by CGI

    Time frame: 6, 9 and 12 month

    Clinical Global Impression (CGI)

  3. Improvement in Psychopathology assessed by BSI-53

    Time frame: 6, 9 and 12 month

    Brief Symptom Inventory (BSI-53)

  4. Improvement in Psychopathology assessed by FROGS

    Time frame: 6, 9 and 12 month

    Functional Remission of General Schizophrenia (FROGS)

  5. Changes from baseline in Depression Scale

    Time frame: 6, 9 and 12 month

    Calgary Depression Scale for Schizophrenia (CDSS)

  6. Improvement in social and occupational functioning assessed by GAF

    Time frame: 6, 9 and 12 month

    Global Assessment of Functioning (GAF)

  7. Improvement in social and occupational functioning assessed by PSP

    Time frame: 6, 9 and 12 month

    Personal and Social Performance Scale (PSP)

  8. Improvement in social and occupational functioning assessed by EMA

    Time frame: 6, 9 and 12 month

    Ecological Momentary Assessment (EMA)

  9. Improvement in Quality of life assessed by WHOQUOL-Bref

    Time frame: 6, 9 and 12 month

    WHO Quality of Life-Bref (WHOQUOL-Bref)

  10. Improvement in Quality of life assessed by LQLP

    Time frame: 6, 9 and 12 month

    Lancashire Quality of Life Profile (LQLP)

  11. Changes from baseline in Neurocognition assessed by B-CATS

    Time frame: 6, 9 and 12 month

    Brief Cognitive Assessment Tool for Schizophrenia (B-CATS)

  12. Changes from baseline in Neurocognition assessed by BACS

    Time frame: 6, 9 and 12 month

    Brief Assessment of Cognition in Schizophrenia (BACS)

  13. Changes from baseline in Neurocognition assessed by UPSA-B

    Time frame: 6, 9 and 12 month

    University of California San Diego Performance based Skills Assessment (UPSA-B)

  14. Changes from baseline in Neurocognition assessed by MASC

    Time frame: 6, 9 and 12 month

    Movie for the Assessment of Social Cognition (MASC)

  15. Changes from baseline in Neurocognition assessed by PFA

    Time frame: 6, 9 and 12 month

    Pictures of Facial Affect (PFA)

  16. Treatment adherence

    Time frame: 6, 9 and 12 month

  17. Changes in Cumulative dose of concomitant or rescue medication

    Time frame: 6, 9 and 12 month

  18. Changes of Biomarker: alterations of endocannabinoids and lipdomic profiling

    Time frame: 6, 9 and 12 month

Other outcomes

  1. Side effects: weight gain

    Time frame: 6, 9 and 12 month

    Body Mass Index, abdominal girth

  2. Side effects: Vital Signs

    Time frame: 6, 9 and 12 month

    heart rate, blood pressure, electrocardiography

  3. Side effects: UKU Side Effect rating scale

    Time frame: 6, 9 and 12 month

  4. Side effects: Abnormal Involuntary Movement Scale (AIMS)

    Time frame: 6, 9 and 12 month

  5. Side effects: Evaluation of extrapyramidal symptoms (EPS)

    Time frame: 6, 9 and 12 month

  6. Side effects: physical and neurological examination

    Time frame: 6, 9 and 12 month

  7. Standard blood tests

    Time frame: 6, 9 and 12 month

  8. Columbia Suicidality Sverity Rating Scale (C-SSRS)

    Time frame: 6, 9 and 12 month

Sponsors and collaborators

Lead sponsor

Central Institute of Mental Health, Mannheim

Other

Registry information

Official study title

Enhancing Recovery in Early Schizophrenia - a Multi-center, Two-arm, Double-blind, Randomized Phase II Trial Investigating Cannabidiol vs. Placebo as an add-on to an Individualized Antipsychotic Treatment

Important dates

Study start
2017
Primary completion
2027
Study completion
2027
First posted
Oct 6, 2016
Registry last updated
Feb 3, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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