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Ginkgo Biloba Extract for Schizophrenia

This study has been completed.
ClinicalTrials.gov Identifier:
First Posted: February 2, 2012
Last Update Posted: July 12, 2016
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by (Responsible Party):
Xiang Yang Zhang, Beijing HuiLongGuan Hospital
A double-blind, randomized, placebo-controlled trial of ginkgo biloba extract (Egb-761) as an add-on therapy to risperidone compared to risperidone plus placebo in the treatment of 200 treatment-naive first-episode patients with schizophrenia. The study addresses an immune dysfunction hypothesis of schizophrenia.

Condition Intervention
Schizophrenia Drug: Ginkgo biloba extract Drug: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Treatment
Official Title: A Double-blind and Randomized Trial of Ginkgo Biloba Extract Added to Risperidone in Treatment-naive First-episode Schizophrenia

Resource links provided by NLM:

Further study details as provided by Xiang Yang Zhang, Beijing HuiLongGuan Hospital:

Primary Outcome Measures:
  • PANSS [ Time Frame: 11 weeks ]

Secondary Outcome Measures:
  • CGI [ Time Frame: 11 weeks ]
  • Cognition [ Time Frame: 11 weeks ]

Enrollment: 124
Study Start Date: September 2011
Study Completion Date: August 2013
Primary Completion Date: June 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Ginkgo biloba extract, antioxidant
Active treatment with Ginkgo biloba extract
Drug: Ginkgo biloba extract
400mg/day, twice a day, 10 weeks
Other Name: EGb761
Placebo Comparator: Placebo
Treatment with placebo
Drug: Placebo
twice a day, 10 weeks
Other Name: EGb761

Detailed Description:

OBJECTIVE: There is evidence that an excessive free radical production or oxidative stress may be involved in the pathophysiology of patients with schizophrenia. The investigators hypothesize that antioxidant therapy by using an add-on agent together with a well-proven antipsychotic drug may have favorable effects on some schizophrenic patients.


  1. Clinical Trial: This is a randomized, double-blind and parallel controlled trial in treatment-naive first-episode patients with schizophrenia. The study consists of a 1-week stabilization phase, followed by 10 weeks of double-blind treatment. The total trial duration is 11 weeks.
  2. Medications: Eligible patients are randomly assigned to either capsulized EGb(240mg.day) or identically capsulized placebo addition to the risperidone (2-6mg/day) in a double-blind fashion.
  3. Assessment Procedures:

3.1. Primary Outcome Variable-psychopathology: Assessment instruments include the Positive and Negative Syndrome Scale (PANSS), and the Clinical Global Impression (CGI). Patients are interviewed at screening, at baseline and at every two weeks.

3.2. Cognitive tests: A comprehensive battery of tests encompassing the cognitive domains of executive function, attention, memory, perception, and general intellect is administered twice at baseline and at the end of 10-week treatment by a trained psychologist. Scoring follows standardized procedures.

3.3. Side Effects: Parkinsonism is rated with the Simpson-Angus Scale for extrapyramidal side effects. The Abnormal Involuntary Movement Scale (AIMS) is chosen to assess tardive dyskinesia (TD) severity. All of the AIMS and Simpson-Angus Rating Scales are administered by the same investigator at baseline and at baseline, and at week 5 and at week 10.

3.4. Plasma Measures: Venous blood from forearm vein is collected from healthy controls and patients with schizophrenia between 7 and 9 a.m. following an overnight fast. Serum Plasma malondialdehyde (MDA) levels and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities will be analyzed using established procedures.


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Ages Eligible for Study:   18 Years to 45 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Diagnosis of schizophrenia or schizophreniform disorder;
  • Duration of symptoms not longer than 60 months;
  • No prior treatment with antipsychotic medication or, if previously treated, a total lifetime usage of less than 14 days;
  • Between 16 and 40 years of age; and
  • Current psychotic symptoms of moderate severity.

Exclusion Criteria:

  • A DSM-IV Axis I diagnosis other than schizophrenia or schizophreniform;
  • Documented disease of the central nervous system that can interfere with the trial assessments including, but not limited to stroke, tumor, Parkinson's disease, Huntington's disease, seizure disorder, history of brain trauma resulting in significant impairment, chronic, infection;
  • Acute, unstable and/or significant and untreated medical illness (e.g., infection, unstable diabetes, uncontrolled hypertension);
  • A clinically significant ECG abnormality in the opinion of the investigator;
  • Pregnant or breast-feeding female;
  • Use of disallowed concomitant therapy;
  • History of severe allergy or hypersensitivity.
  Contacts and Locations
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): NCT01524380

Beijing HuiLongGuan Hospital
Beijing, China, 100096
Sponsors and Collaborators
Beijing HuiLongGuan Hospital
Principal Investigator: Xiang Y Zhang, MD/PhD Beijing HuiLongGuan Hospital
  More Information

Responsible Party: Xiang Yang Zhang, co-Director, Psychiatric Research Center, Beijing HuiLongGuan Hospital
ClinicalTrials.gov Identifier: NCT01524380     History of Changes
Other Study ID Numbers: Sch-FEP-001
First Submitted: January 28, 2012
First Posted: February 2, 2012
Last Update Posted: July 12, 2016
Last Verified: July 2016

Keywords provided by Xiang Yang Zhang, Beijing HuiLongGuan Hospital:
clinical trial
ginkgo biloba extract

Additional relevant MeSH terms:
Schizophrenia Spectrum and Other Psychotic Disorders
Mental Disorders
Serotonin Antagonists
Serotonin Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Antipsychotic Agents
Tranquilizing Agents
Central Nervous System Depressants
Psychotropic Drugs
Dopamine Antagonists
Dopamine Agents
Protective Agents