Relationship Between Neurotransmitter Receptor Polymorphisms, Plasma Concentrations and Clinical Response to Clozapine

Completed

• Conditions: Schizophrenia

• Registration Number: NCT00581932
• Lead Sponsor: Delwyn D. Miller

Brief Summary

This is a study designed to identify genetic polymorphisms (also called allelic variants or genetic markers) that are associated with response to clozapine. This information will be used to enhance the understanding of clozapine response and side effects. DNA from patients will be examined for significant associations between allelic variants in candidate genes in relation to clozapine effects on positive and negative symptoms, global response, quality of life, relapse rates and side effects.

Detailed Description

Patients age 18-65 with a DSM IV diagnosis of schizophrenia who have a history of nonresponse to conventional atypical antipsychotics and who are to be treated with clozapine by their psychiatrist, will be asked to participate at or near the time clozapine therapy is initiated. The Brief Psychiatric Rating Scale (BPRS), Scale for the Assessment of Negative Symptoms (SANS), and the Scale for the Assessment of Positive Symptoms (SAPS) will be performed on all subjects at entry into the study, at 3 weeks, 5 weeks, 8 weeks, and at 4 and 6 months. Adverse effects will be monitored with the Simpson-Angus Scale, Barnes Akathisia scale and the AIMS at each of these time points. The Calgary Depression Scale will also be administered at each visit. A complete neurocognitive assessment battery will be completed at entry and at 6 months for those subjects willing to undergo neurocognitive testing. It is anticipated not all subjects will complete neurocognitive testing. A blood or cheek swab sample will be collected at study entry for DNA analysis. Plasma blood levels will be collected at weeks 3, 5, 8 and study completion for measurement of clozapine plasma concentrations. The subject's weight, BMI, smoking status and concomitant medications will be recorded at each visit.

Study Timeline

• Study Start: 2001-10
• Study First Submitted: 2007-12-19
• Study First Submitted QC: 2007-12-19
• Study First Posted: 2007-12-28
• Primary Completion: 2015-12
• Study Completion: 2015-12
• Status Verified: 2017-05
• Last Update Submitted: 2017-05-11
• Last Update Posted: 2017-05-12

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 76

Inclusion Criteria

• Diagnosis of schizophrenia
• Beginning clozapine therapy
• age 18-65
• must be willing to participate in interviews and provide a DNA sample

Exclusion Criteria

• no longer taking clozapine

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Brief Psychiatric Rating Scale	entry, 3 wks, 5 wks, 8 wks, 4 mo, 6 mo

Secondary Outcome Measures

Name	Time	Method
Calgary Depression Scale	entry, 3 wk, 5 wk, 8 wk, 4 mo, 6 mo
Scale for the Assessment of Positive Symptoms	entry, wk 3, wk 5, wk 8, 4 mo, 6 mo
Scale for the assessment of Negative symptoms	entry, 3 wk, 5 wk, 8 wk, 4 mo, 6 mo
Abnormal Involuntary Movement Scale	entry, 3 wk, 5 wk, 8 wk, 4 mo, 6 mo
Barnes Akathisia Scale	entry, 3 wk, 5 wk, 8 wk, 4 mo, 6 mo

Trial Locations

Locations (1)

University of Iowa Hospitals and Clinics; 🇺🇸 Iowa City, Iowa, United States