Sodium Benzoate and/or N-Acetylcysteine Added to TAU in Patients With Early Schizophrenia Spectrum Disorder.


This study aims to determine if the addition of Sodium Benzoate and / or NAC to TAU will be acceptable and tolerable and result in overall improvement of symptoms, social and cognitive functioning in patients with early schizophrenia spectrum disorder.

Full Title of Study: “A Multicentre 12-week Randomised Double-blind Placebo Controlled Feasibility Trial of Sodium Benzoate and/or N-acetylcysteine Added to TAU in Patients With Early Schizophrenia Spectrum Disorder.”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Factorial Assignment
    • Primary Purpose: Other
    • Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
  • Study Primary Completion Date: April 30, 2020


  • Drug: Sodium Benzoate
    • Sodium Benzoate will be administered at 1000mg daily
  • Drug: N-Acetylcysteine
    • N-Acetylcysteine 1000 mgs twice daily dose
  • Drug: Placebo
    • Placebo added to TAU
  • Drug: Sodium Benzoate Plus N-Acetylcysteine
    • Sodium Benzoate will be administered at 1000mg daily and NAC 1000 mgs twice daily dose

Arms, Groups and Cohorts

  • Active Comparator: Sodium Benzoate
    • Sodium Benzoate added to TAU will be administered at 1000mg daily
  • Active Comparator: N-Acetylcysteine
    • N-Acetylcysteine added to TAU 1000 mgs twice daily dose
  • Active Comparator: Placebo
    • Placebo added to TAU
  • Active Comparator: Sodium Benzoate Plus N-Acetylcysteine
    • Sodium Benzoate will be administered at 1000mg daily and NAC 1000 mgs twice daily dose

Clinical Trial Outcome Measures

Primary Measures

  • Feasibility of intervention ( including recruitment rates and drop outs)
    • Time Frame: 12 weeks
    • Feasibility estimates of delivering the intervention including recruitment rates and drop outs

Secondary Measures

  • Overall improvement in symptoms using the Positive and Negative Syndrome Scale (PANSS) total score
    • Time Frame: 12 weeks
    • The PANSS is measured on a 7-point scale, and is a 30-item structured clinical interview assessing symptom severity over the previous week. The PANSS scale has a maximum score of 210 and a minimum of 30. Higher scores indicate higher severity of illness.

Participating in This Clinical Trial

Inclusion Criteria

1. Male/Female patients aged between 18-35 years.

2. Diagnosis of schizophrenia confirmed by SCID interview meeting DSM-V criteria for schizophrenia, schizophreniform or schizoaffective psychosis.

3. Stable on medication for the past four weeks

4. In contact with mental health services

5. Within 5 years of diagnosis of psychotic illness

6. Able to demonstrate the capacity to provide informed consent as assessed by their own clinician

7. Able to complete the required evaluations and take oral medication.

8. Effective contraceptive precautions (either the use of barrier methods or the oral contraceptive pill) to be taken by women of child-bearing age. A negative pregnancy test will be required in order to meet inclusion criteria.

Exclusion Criteria

1. Prior history of intolerance or serious side effects to Sodium Benzoate or N-acetylcystine.

2. Concomitant use of Ascorbic acid

3. Active substance abuse (except nicotine or caffeine) or dependence within the last three months according to DSM-V criteria.

4. Relevant CNS or other medical disorders.

5. Pregnant or breast feeding

6. Diagnosis of Moderate to Severe Learning Disability

7. Relevant current or past haematological, hepatic, renal, neurological or other medical disorder in the opinion of the principal investigator (PI) or the responsible clinician, that may interfere with the trial.

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: 35 Years

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Pakistan Institute of Living and Learning
  • Provider of Information About this Clinical Study
    • Sponsor
  • Overall Official(s)
    • Imran B Chaudhry, MD, Principal Investigator, Ziauddin Hospital
  • Overall Contact(s)
    • Ameer B Khoso, 021-35871845,


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