Ginkgo Biloba Extract for Schizophrenia
Condition: Schizophrenia
MeSH terms: Schizophrenia
Study type: Interventional

Summary: 
      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.
    

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.

      METHODS:

        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.
    

Intervention name(s): Ginkgo biloba extract; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): 400mg/day, twice a day, 10 weeks; twice a day, 10 weeks
Other intervention name(s): EGb761; EGb761
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: Schizophrenia; clinical trial; risperidone; ginkgo biloba extract; antioxidant