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Completed

NCT Number: NCT00169065

Effectiveness of Clozapine Versus Olanzapine for Treatment-resistant Schizophrenia

This study will determine the effectiveness of clozapine versus olanzapine in treating people with schizophrenia that has not improved with treatment.

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Key information

Conditions

Schizophrenia Mental Disorders Schizophrenia Spectrum and Other Psychotic Disorders

Age range

20 year–60 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Commonwealth Research Center

Jamaica Plain, Massachusetts, 02130, United States

About this study

This is a two-year open-label, randomized trial of the comparative effectiveness of clozapine versus olanzapine in patients with treatment refractory schizophrenia. The objective is to determine whether in a naturalistic setting olanzapine is a logical treatment choice (before using the more toxic clozapine) for some treatment refractory patients.

Who can participate

Healthy volunteers accepted: No

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

Inclusion criteria

  • Age 20-60 years;
  • Diagnosis of treatment refractory schizophrenia or schizoaffective disorder;
  • BPRS score > 21 (0-6) scale;
  • Either two 6-8 week trials of typical neuroleptics given at a dosage of 600 mg/day of CPZ or its equivalent or one 6-8 week trial of an atypical antipsychotic at a reasonable dose (i.e. risperidone 4-6 mg/day);
  • The patient (or the patient's authorized legal representative) must understand the nature of the study and sign the informed consent;
  • Clinically appropriate for clozapine or olanzapine

Exclusion criteria

  • Current substance abuse;
  • Suicide or homicide risk;
  • Pregnancy or lactation;
  • History of seizures or blood dyscrasias

Treatment and study plan

Clozapine

Drug

Olanzapine

Drug

Primary outcomes

  1. Changes in quality of life.

Secondary outcomes

  1. Symptom measures, neurological side effects, neuropsychological performance, patient satisfaction and burden on the family.

Sponsors and collaborators

Lead sponsor

Harvard Medical School (HMS and HSDM)

Other

Collaborators

  • Commonwealth Research Center, Massachusetts
  • Dartmouth-Hitchcock Medical Center
  • Eli Lilly and Company
  • National Institute of Mental Health (NIMH)

Registry information

Official study title

Clozapine vs. Olanzapine: An Effectiveness Study

Acronym: COES

Important dates

Study start
1998
Primary completion
2002
Study completion
2002
First posted
Sep 15, 2005
Registry last updated
Apr 7, 2015

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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