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OpenTrials
Completed

NCT Number: NCT00431574

Antipsychotic Medication Extended Dosing Study

In patients stabilized on their antipsychotic and demonstrating evidence of good clinical response, there will not be a significant change in symptoms if their medication is decreased to every 2 days rather than daily. This decrease in antipsychotic exposure will lead to a reduction in side effects, as well as improved subjective response to treatment.

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Key information

Conditions

Schizophrenia Mental Disorders Schizophrenia Spectrum and Other Psychotic Disorders

Age range

18 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Centre for Addiction and Mental Health

Toronto, Ontario, M5T 1R8, Canada

About this study

The present study is a 6-month, double-blind study of patients with schizophrenia stabilized on their current antipsychotic (monotherapy) for a period of at least 3 months. After providing informed consent, individuals will be randomly assigned to 1 of 2 treatment arms: regular daily antipsychotic dosing or active medication at the same daily dose every 2nd day. Various scales to measure clinical response and side effects will be administered at baseline, as well as every 2 weeks thereafter. Subjective scales will also be employed, and lab evaluations will include plasma antipsychotic levels at baseline and endpoint, as well as prolactin. Our sample size will be 20/group.

Who can participate

Healthy volunteers accepted: No

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

Inclusion criteria

  • DSM-IV diagnosis of schizophrenia or schizo-affective disorder
  • Capacity to provide written, informed consent
  • Stabilized* on a single oral antipsychotic for at least three months (excluding CLOZAPINE or QUETIAPINE)
  • Evidence of compliance with previous antipsychotic treatment, i.e. greater than 90% * defined as 2 consecutively identical CGI evaluations (screening and baseline, at least one week apart)

Exclusion criteria

  • exposure to depot antipsychotic during 12 months prior to enrollment
  • substance-related disorders according to DSM-IV

Treatment and study plan

dosing

Procedure

Primary outcomes

  1. Clinical Global Impression every 2 weeks

  2. Simpson and Angus Rating Scale for Extrapyramidal Effects every 2 weeks

  3. Barnes Rating Scale for Drug-Induced Akathisia every 2 weeks

  4. Abnormal Involuntary Movement Scale every 2 weeks

  5. Drug Attitude Inventory every 2 weeks

  6. Calgary Depression Scale for Schizophrenia every 2 weeks

  7. Brief Psychiatric Rating Scale every 2 weeks

Sponsors and collaborators

Lead sponsor

Centre for Addiction and Mental Health

Other

Collaborators

  • National Alliance for Research on Schizophrenia and Depression

Registry information

Important dates

Study start
2002
Primary completion
2007
Study completion
2007
First posted
Feb 6, 2007
Registry last updated
Feb 7, 2024

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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