|
Home
Search
Study Topics
Glossary
|
![]() |
![]() |
|
![]() |
|
![]() |
|
![]() |
![]() |
![]() |
|
![]() |
![]() |
||||||||||||||||||||||||||||||||||||
| Sponsor: | Centre for Addiction and Mental Health |
|---|---|
| Information provided by (Responsible Party): | Centre for Addiction and Mental Health |
| ClinicalTrials.gov Identifier: | NCT00716755 |
Purpose
Since side effects of antipsychotics, dopamine D2 receptor blockers, frequently occur in older patients with schizophrenia and the risk is dose dependent, clinical guidelines universally advocate the use of lower doses. However, there is no report to test this dosing guideline with measurements of D2 receptor blockade caused by antipsychotics. In this study, dopamine D2 receptor occupancy will be measured, using Positron Emission Tomography (PET), in 40 patients aged 50 and older with schizophrenia-spectrum disorders before and after a gradual 40 % dose reduction of antipsychotics that was safely achieved in the past study while setting a target dose still above the lower limit of the dose range recommended in clinical guidelines for older patients. Our goal is to relate changes in clinical outcome, including subjective and objective clinical ratings, to dopamine D2 receptor occupancy, and compare these results with the data for younger patients in the literature.
| Condition | Intervention |
|---|---|
|
Schizophrenia Schizoaffective Disorder Schizophreniform Disorder Delusional Disorder Psychotic Disorder |
Drug: Risperidone/Olanzapine and PET scans |
| Study Type: | Interventional |
| Study Design: | Intervention Model: Single Group Assignment Masking: Open Label Primary Purpose: Treatment |
| Official Title: | The Minimal Effective Dose of Antipsychotic Medication in Older Patients With Schizophrenia: a PET Study. |
| Estimated Enrollment: | 40 |
| Study Start Date: | October 2009 |
| Estimated Primary Completion Date: | January 2015 (Final data collection date for primary outcome measure) |
| Arms | Assigned Interventions |
|---|---|
| Experimental: 1 |
Drug: Risperidone/Olanzapine and PET scans
Current risperidone/olanzapine users who are 50 or older will be recruited. Dopamine D2 dopamine receptors using a selective D2 dopamine receptor ligand, [11C]-raclopride, and plasma levels of risperidone and 9-OH-risperidone, or of olanzapine, and prolactin will be measured on the 1st PET visit. Subsequently, there will be gradual dose reductions of risperidone or olanzapine by 0.5 and 2.5 mg per week, respectively (as long as the total reduction does not exceed 40%). At least 5 days after the termination of the dose taper, participants will have the second PET scan. Participants will be followed up for 24 weeks after the termination of the dose reduction.
|
Show Detailed Description
Eligibility| Ages Eligible for Study: | 50 Years and older |
| Genders Eligible for Study: | Both |
| Accepts Healthy Volunteers: | No |
Inclusion Criteria:
Exclusion Criteria:
Contacts and Locations| Contact: Ariel Graff-Guerrero, MD, PhD | 416-535-8501 ext 4834 | ariel_graff@camh.net |
| Canada, Ontario | |
| Centre for Addiction and Mental Health | Recruiting |
| Toronto, Ontario, Canada, M5T 1R8 | |
| Sub-Investigator: Benoit Mulsant, MD | |
| Sub-Investigator: Bruce Pollock, MD PhD | |
| Sub-Investigator: Shinichiro Nakajima, MD, PhD | |
| Principal Investigator: | David C. Mamo, MD MSc | Centre for Addiction and Mental Health |
| Principal Investigator: | Ariel Graff-Guerrero, MD,PhD | Centre for Addiction and Mental Health |
More Information
| Responsible Party: | Centre for Addiction and Mental Health |
| ClinicalTrials.gov Identifier: | NCT00716755 History of Changes |
| Other Study ID Numbers: | 156/2007 |
| Study First Received: | July 14, 2008 |
| Last Updated: | October 7, 2011 |
| Health Authority: | Canada: Health Canada |
|
Positron emission tomography antipsychotics risperidone olanzapine Dopamine D2 receptor |
elderly schizophrenia schizoaffective disorder schizophreniform disorder delusional disorder psychotic disorder NOS |
|
Schizophrenia, Paranoid Delusions Psychotic Disorders Mental Disorders Schizophrenia Schizophrenia and Disorders with Psychotic Features Behavioral Symptoms Antipsychotic Agents Risperidone Olanzapine Tranquilizing Agents Central Nervous System Depressants Physiological Effects of Drugs Pharmacologic Actions Central Nervous System Agents |
Therapeutic Uses Psychotropic Drugs Serotonin Antagonists Serotonin Agents Neurotransmitter Agents Molecular Mechanisms of Pharmacological Action Dopamine Antagonists Dopamine Agents Serotonin Uptake Inhibitors Neurotransmitter Uptake Inhibitors Antiemetics Autonomic Agents Peripheral Nervous System Agents Gastrointestinal Agents |