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Do Antipsychotic Agents Induce Supersensitivity in Humans: A Combined PET/MRI Study in Patients With Schizophrenia

Not Applicable
Active, not recruiting
Conditions
Schizophrenia
Interventions
Radiation: Single PET/MR-measurement
Registration Number
NCT03911726
Lead Sponsor
Central Institute of Mental Health, Mannheim
Brief Summary

The aim of the present study is to detect changes in the dopamine system in the brain of patients with schizophrenia, especially when pretreated with antipsychotic medication. Here, the investigators want to find out whether the treatment with these drugs can cause permanent changes in docking points (receptors) of dopamine in the brain. It will be examined whether number and response of dopamine receptors is altered, which are associated with the onset of psychotic symptoms. For this purpose, a single PET/MR measurement will be performed in all participants. In total 140 volunteers, consisting of 30 healthy volunteers, 20 first-episode, drug-naive patients with schizophrenia and 90 pretreated patients with schizophrenia will be included over a time period of three years. In addition, the influence of nicotine consumption on dopamine receptors will be invesitgated by comparing data from smoking and non-smoking patients. In clinical practice, an elevation of dopamine action caused by alterations in receptors in the brain is of most importance. This may be the reason why the treatment with antipsychotic agents does not work in some patients. In addition, a permanent elevation of dopamine action is associated with permanent brain alterations by these drugs. The result can contribute to work out valuable indications, whether it makes sense to continue a long term therapy with antipsychotic drugs in a patient. But also the in-depth understanding of the impact of nicotine on the course of therapy can help to open up possibilities for improved drug treatment.

Detailed Description

This project will study for the first time in humans, whether long-term treatment with antipsychotic agents, representing nowadays gold standard for patients with schizophrenia, may lead to an up regulation of dopamine D2-like receptors and associated, a supersensitivity of these receptors. The detection of such changes and the study of influencing factors (in particular smoking and type of medication) are most important for the understanding of relapse risks, development of treatment resistance and the risks for motor complications of antipsychotic pharmacotherapy. This monocentric, controlled study will include 140 participants over a time period of three years. 30 healthy volunteers, 20 first-episode, drug-naive patients with schizophrenia and 90 pretreated patients with schizophrenia will undergo a single PET/MR measurement.

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
140
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Pretreated chronically ill patients with schizophreniaSingle PET/MR-measurement90 pretreated chronically ill patients with schizophrenia will undergo a single PET/MR-measurement.
First-episode, drug-naive patients with schizophreniaSingle PET/MR-measurement20 first-episode, drug-naive patients with schizophrenia will undergo a single PET/MR-measurement.
Healthy subjectsSingle PET/MR-measurement30 healthy subjects will undergo a single PET/MR-measurement.
Primary Outcome Measures
NameTimeMethod
Dopamine D2/D3-receptor availability160 minutes

Dopamine D2/D3-receptor availability measured as binding potential (BP) using PET and blood-oxygen-level-dependant (BOLD)-response measured with fMRI.

Secondary Outcome Measures
NameTimeMethod
D2/D3-receptor availability in first-episode, drug-naive patients with schizophrenia160 minutes

In first-episode, drug-naive patients with schizophrenia expressions of NSS and AIMS correlate significantly with striatal D2/D3-receptor availability.

D2/D3-receptor availability in patients with TD160 minutes

In pretreated, chronically ill patients with schizophrenia, patients with TD show a significantly higher D2/D3-receptor availability than patients without TD.

Follow-up of pretreated, chronically ill patients with schizophreniatwo years

In pretreated, chronically ill patients with schizophrenia, the D2/D3-receptor availability correlates with the relapse risk and the risk for the development of TD over the course of two years.

Trial Locations

Locations (1)

Central Institute of Mental Health

🇩🇪

Mannheim, Baden-Württemberg, Germany

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