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Evaluation of the Antipsychotic Efficacy of Cannabidiol in Acute Schizophrenic Psychosis (CBD-CT1)

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ClinicalTrials.gov Identifier: NCT00628290
Recruitment Status : Completed
First Posted : March 5, 2008
Last Update Posted : March 18, 2008
Information provided by:
University of Cologne

Brief Summary:

A controlled, randomized study on the treatment of schizophrenic psychosis with cannabidiol, a phytocannabinoid is performed. This approach is based upon recent findings indicating that the human endogenous cannabinoid system is significantly involved in the pathogenesis of schizophrenia. Our group has shown, for example, that Δ9-tetrahydrocannabinol (Δ9-THC) is able to provoke schizophrenia-like psychotic symptoms in healthy volunteers. This, as well as the capability of Δ9-THC to exacerbate productive psychotic symptoms in schizophrenic patients, has recently been confirmed by others. Furthermore, we found that the en-dogenous brain constituent anandamide, an endogenous Δ9-THC agonist, is significantly elevated in the CSF of schizophrenic patients. Cannabinergic substances such as anandamide may enhance dopaminergic neurotrans-mission by increasing dopamine turnover. They may also influence the onset or course of schizophrenia by as yet unidentified mechanisms We seek to investigate the efficacy of cannabidiol in the treatment of schizophrenic and schizophreniform psy-choses, because there is evidence that CB1 antagonists such as SR141716 and cannabidiol have antipsychotic effects comparable to those of classic neuroleptic drugs. Furthermore, cannabidiol is well tolerated showing few side effects in humans. Cannabidiol may serve as an antipsychotic medication that is not primarily based upon an antidopaminergic but upon different mechanisms, especially anticannabinergic ones. It may therefore be an effec-tive medication in at least a subgroup of schizophrenic and schizophreniform patients and may be expected to show additional anxiolytic effects and only minor side effects.

The control condition in this parallel design will be an established neuroleptic treatment with amisulpride that is primarely an antidopaminergic drug. Thus, we will study not only the antipsychotic efficacy of cannabidiol, but we will also compare the effects of both treatment strategies on side effects and neuropsychological functioning.

Condition or disease Intervention/treatment Phase
Schizophrenia Drug: Cannabidiol Drug: Amisulpride Phase 2

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 42 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Evaluation of the Antipsychotic Efficacy of the Phytocannabinoid Cannabidiol in Treating Acute Schizophrenic Psychosis. A Double-Blind, Controlled Clinical Trial
Study Start Date : October 2002
Actual Primary Completion Date : November 2004
Actual Study Completion Date : March 2008

Arm Intervention/treatment
Experimental: 1 Drug: Cannabidiol
Capsules, 3 times daily, 200 mg, 4 weeks

Active Comparator: 2 Drug: Amisulpride
Capsules, 3 times daily, 200 mg, 4 weeks

Primary Outcome Measures :
  1. Change in BPRS total value. [ Time Frame: 4 weeks ]

Secondary Outcome Measures :
  1. Change in PANSS scores. [ Time Frame: 4 weeks ]
  2. EPS [ Time Frame: 4 weeks ]
  3. Weight gain [ Time Frame: 4 weeks ]
  4. Prolactin levels in serum [ Time Frame: 4 weeks ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Clinical diagnosis of schizophrenia or schizophreniform psychosis according to DSM-IV.
  • BPRS score >36 and BPRS psychosis cluster > 12.
  • Ability to provide written informed consent.
  • Participants are required an adequate contraception.

Exclusion Criteria:

  • Any severe neurological or somatic disorder.
  • Other psychiatric disorders including addictive disorders.
  • Positive urine drug screening for any compound except benzodiazepines.
  • No pregnancy or breast feeding.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00628290

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University of Cologne, Dept. of Psychiatry and Psychotherapy
Cologne, NRW, Germany, 50924
Sponsors and Collaborators
University of Cologne
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Principal Investigator: Franz-Markus Leweke, MD University of Cologne, Dept. of Psychiatry and Psychotherapy
Additional Information:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: Dr. F. Markus Leweke, University of Cologne
ClinicalTrials.gov Identifier: NCT00628290    
Other Study ID Numbers: CBD-CT1
SMRI Grant ID: 00-093
First Posted: March 5, 2008    Key Record Dates
Last Update Posted: March 18, 2008
Last Verified: January 2008
Additional relevant MeSH terms:
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Schizophrenia Spectrum and Other Psychotic Disorders
Mental Disorders
Antipsychotic Agents
Tranquilizing Agents
Central Nervous System Depressants
Physiological Effects of Drugs
Psychotropic Drugs
Dopamine Antagonists
Dopamine Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Antidepressive Agents, Second-Generation
Antidepressive Agents