Clinical Trials Logo

Clinical Trial Details — Status: Active, not recruiting

Administrative data

NCT number NCT00825045
Other study ID # 270/2008
Secondary ID
Status Active, not recruiting
Phase N/A
First received
Last updated
Start date December 2008
Est. completion date December 2020

Study information

Verified date February 2020
Source Centre for Addiction and Mental Health
Contact n/a
Is FDA regulated No
Health authority
Study type Interventional

Clinical Trial Summary

This study will provide information regarding dopamine D2/D3 occupancy related with clinical/adverse effects in older people with schizophrenia and schizoaffective disorder. The results of this study will also show an appropriate dose range in order to evade undesirable adverse effects while deriving therapeutic effects, which will directly serve to guide physicians in clinical practice. Furthermore, the findings of this study will elucidate mechanisms underlying older people's increased sensitivity to antipsychotic drugs. In addition, the contribution of D2 and D3 in mediating antipsychotic response will be contrasted, using 2 radiotracers, which has never been tested in an older population.

The hypotheses are as follows: First, clinical response (i.e., a ≥ 20% decrease in the Brief Psychiatric Rating Scale total score) will be achieved in older patients with occupancy that is lower than the threshold of 60% in historical young controls. Second, prolactin elevation and EPS will be detected in older patients with occupancies that are lower than the thresholds of 72 and 78% reported in historical young controls. Third, dopamine D2 receptor occupancy will be inversely correlated with subjective well-beings. Fourth, the binding potential and receptor occupancy will be at least 20% lower with [11C]-(+)-PHNO than with [11C]-raclopride in the caudate/putamen. Fifth, the binding of [11C]-(+)-PHNO in the globus pallidus will be higher than that of [11C]-raclopride.


Description:

Positron Emission Tomography (PET) studies have demonstrated that a therapeutic window of dopamine D2/3 receptor occupancy (60-80%) is associated with clinical response in younger patients with schizophrenia. This observation has been used to predict the therapeutic dose range and contributed to current recommended antipsychotic doses. To date, there is no published report to examine D2/3 receptor occupancy associated with clinical response in older individuals with primary psychotic disorders. This has has impeded the implementation of treatment guidelines.

The investigators therefore propose a prospective study to assess dopamine D2 and D3 receptor occupancy following acute antipsychotic treatment in patients aged 50 and older with schizophrenia who do not currently receive antipsychotic treatment, using both [11C]-(+)-PHNO and [11C]-raclopride PET scans. Dopamine D2/3 receptor occupancy of risperidone that are associated with clinical effects will be measured, using PET, in older patients with schizophrenia. The investigators will also try to contrast the contribution of D2 and D3 in mediating antipsychotic response, using 2 radiotracers.

Our primary goal is to relate changes in clinical outcome, including subjective and objective clinical ratings, to dopamine D2 and D3 receptor occupancy in older patients with schizophrenia, and compare these results with the data for younger patients in the literature.


Recruitment information / eligibility

Status Active, not recruiting
Enrollment 14
Est. completion date December 2020
Est. primary completion date December 2020
Accepts healthy volunteers No
Gender All
Age group 50 Years and older
Eligibility Inclusion Criteria:

- Age of 50 and older at time of scanning

- Inpatients or outpatients

- DSM-IV/SCID diagnosis of schizophrenia, schizoaffective disorder, or schizophreniform disorder

- Having NOT been treated with oral antipsychotic treatment for at least 2 weeks or long-acting antipsychotics for at least 6 months (Please note that patients will not be withdrawn from antipsychotic medications for the purpose of meeting inclusion criteria for this study).

Exclusion Criteria:

- Known history of intolerance or inefficacy to risperidone

- Participation in this study would result in exceeding the annual radiation dose limits (20 mSv) for human subjects participating in research studies.

- Substance abuse or dependence (within past six months)

- Positive urine drug screen

- Positive serum pregnancy test at screening or positive urine pregnancy test before PET scan

- Metal implants or a pace-maker that would preclude the MRI scan

- History of head trauma resulting in loss of consciousness >30 minutes that required medical attention

- Unstable physical illness or significant neurological disorder including a seizure disorder

- Inappropriate size of head, neck, and body to be able to fit the PET and MRI scans

Study Design


Intervention

Drug:
risperidone
Following the baseline clinical and cognitive assessments, risperidone will be initiated at 0.5-1.0 mg/day and subsequently increased by 0.25 - 1.0 mg on a weekly basis with the target of clinical stabilization (i.e. 20 or more % reduction in the total BPRS score) until a maximum dose of 4.0 mg/day is reached. To achieve this, a weekly assessment with BPRS will be performed. Physicians-of-record will be closely liaised with investigators. Dosage modification will be performed following this dosing schedule, however, this can be changed by treating physicians to meet clinical necessity. For example, in case psychotic symptoms are not controlled by this dosing schedule, facilitated dose increment will be allowed.

Locations

Country Name City State
Canada Centre for Addiction and Mental Health Toronto Ontario

Sponsors (1)

Lead Sponsor Collaborator
Centre for Addiction and Mental Health

Country where clinical trial is conducted

Canada, 

Outcome

Type Measure Description Time frame Safety issue
Primary The occupancy of risperidone at the D2 and D3 receptor, using [11C]-raclopride and [11C]-(+)-PHNO, respectively. Within 3 months of enrollment
Secondary Plasma levels of risperidone and 9-hydroxyrisperidone Within 3 months of enrollment
See also
  Status Clinical Trial Phase
Recruiting NCT05039489 - A Study on the Brain Mechanism of cTBS in Improving Medication-resistant Auditory Hallucinations in Schizophrenia N/A
Completed NCT05111548 - Brain Stimulation and Cognitive Training - Efficacy N/A
Completed NCT05321602 - Study to Evaluate the PK Profiles of LY03010 in Patients With Schizophrenia or Schizoaffective Disorder Phase 1
Completed NCT04503954 - Efficacy of Chronic Disease Self-management Program in People With Schizophrenia N/A
Completed NCT02831231 - Pilot Study Comparing Effects of Xanomeline Alone to Xanomeline Plus Trospium Phase 1
Completed NCT05517460 - The Efficacy of Auricular Acupressure on Improving Constipation Among Residents in Community Rehabilitation Center N/A
Completed NCT03652974 - Disturbance of Plasma Cytokine Parameters in Clozapine-Resistant Treatment-Refractory Schizophrenia (CTRS) and Their Association With Combination Therapy Phase 4
Recruiting NCT04012684 - rTMS on Mismatch Negativity of Schizophrenia N/A
Recruiting NCT04481217 - Cognitive Factors Mediating the Relationship Between Childhood Trauma and Auditory Hallucinations in Schizophrenia N/A
Completed NCT00212784 - Efficacy and Safety of Asenapine Using an Active Control in Subjects With Schizophrenia or Schizoaffective Disorder (25517)(P05935) Phase 3
Completed NCT04092686 - A Clinical Trial That Will Study the Efficacy and Safety of an Investigational Drug in Acutely Psychotic People With Schizophrenia Phase 3
Completed NCT01914393 - Pediatric Open-Label Extension Study Phase 3
Recruiting NCT03790345 - Vitamin B6 and B12 in the Treatment of Movement Disorders Induced by Antipsychotics Phase 2/Phase 3
Recruiting NCT05956327 - Insight Into Hippocampal Neuroplasticity in Schizophrenia by Investigating Molecular Pathways During Physical Training N/A
Terminated NCT03261817 - A Controlled Study With Remote Web-based Adapted Physical Activity (e-APA) in Psychotic Disorders N/A
Terminated NCT03209778 - Involuntary Memories Investigation in Schizophrenia N/A
Completed NCT02905604 - Magnetic Stimulation of the Brain in Schizophrenia or Depression N/A
Recruiting NCT05542212 - Intra-cortical Inhibition and Cognitive Deficits in Schizophrenia N/A
Completed NCT04411979 - Effects of 12 Weeks Walking on Cognitive Function in Schizophrenia N/A
Terminated NCT03220438 - TMS Enhancement of Visual Plasticity in Schizophrenia N/A