Does tDCS Change Synaptic Density in the Brains of Patients With Schizophrenia

NCT05435300 | Recruiting

• 1 other identifier: 118/2020
• Study Type: observational
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

This study will examine changes in synaptic density with transcranial direct current stimulation (tDCS) in the brains of patients with schizophrenia. Synaptic density levels will be measured using a novel positron emission tomography (PET) radiotracer \[18F\]SDM-8, which is currently the best-in-class method to quantify synaptic density in humans. This will be a companion study to a parent study by our group examining the effects of tDCS on treatment adherence in schizophrenia (REB #103-2018).

Conditions

Schizophrenia; Schizoaffective

Keywords

Positron emission tomography

Outcome Measures

Primary Outcomes (1)

• Synaptic density changes

  The primary outcome measure is the \[18F\]SDM-8 standard uptake value (SUV) and distribution volume ratio (DVR) in cortical and subcortical gray matter regions, measured by PET Scans

  PET scans will be timed to coincide to the two time-points, before and after 2-weeks of tDCS treatment that is completed under the parent study protocol (REB #103-2018)

Study Arms (1)

Schizophrenia/Schizoaffective Disorder

Participants with Schizophrenia/Schizoaffective Disorder and currently enrolled in the tDCS-adherence parent study (REB# 103-2018).

Other: PET Scan

Interventions

PET Scan OTHER

Participants will undergo two PET scans throughout the study.

Schizophrenia/Schizoaffective Disorder

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Participants will have Schizophrenia/Schizoaffective Disorder and currently enrolled in the tDCS-adherence parent study (REB# 103-2018).

You may qualify if:

• Male or female participants of any race or ethnicity
• Inpatients or outpatients ≥18 years of age
• DSM-V diagnosis of schizophrenia or schizoaffective disorder
• Capable of consenting to participate in the research study
• On a stable dose of oral antipsychotic drug and other concomitant medications for at least 2 months, and unlikely to undergo changes in dose during the study.

You may not qualify if:

• Unwilling or incapable to consent to the study based on the MacArthur Test of Competence
• Unstable medical or any concomitant major medical or neurological illness, including a history of seizures
• Acute suicidal or homicidal ideation
• Formal thought disorder rating ≥3 on the Positive and Negative Syndrome Scale (PANSS) P2 conceptual disorganization item
• DSM-V substance dependence (except caffeine, nicotine, and cannabis/marijuana) within 1 month of entering the study
• Positive urine drug screen except for cannabis/marijuana at the screening visit
• Metal implants or pacemaker precluding an MRI scan or other contraindications to MRI (e.g., claustrophobia)
• Pregnancy
• Score \<32 on the Wide Range Achievement Test-III
• Unwilling or incapable to consent to the study based on the MacArthur Test of Competence
• Exposure to long-acting injectable antipsychotics in the last 6 months
• Exceeding allowed annual radiation exposure levels (20 mSv), as outlined by our PET Centre guidelines
• Receiving treatment with medications such as levetiracetam that blocks SV2a binding
• Disorders of coagulation or taking anticoagulant medication
• Having completed multiple PET scans in the past, such that participation in this study would cause participant to exceed lifetime limit (8 PET scans)

Sponsors & Collaborators

• Centre for Addiction and Mental Health: lead

Study Sites (1)

Centre for Addiction and Mental Health

Toronto, Ontario, M5T 1R8, Canada

RECRUITING

Related Links

• The Centre for Addiction and Mental Health (CAMH) is the leading mental health and addictions research facility in Canada, and one of the largest in the world.

Biospecimen

Retention: SAMPLES WITHOUT DNA

Plasma

MeSH Terms

Conditions

Schizophrenia

Interventions

Magnetic Resonance Spectroscopy

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Spectrum Analysis; Chemistry Techniques, Analytical; Investigative Techniques

Study Officials

• Philip Gerretsen, MD, PhD

  Centre for Addiction and Mental Health

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Philip Gerretsen, MD, PhD

CONTACT

416-535-8501; philip.gerretsen@camh.ca

Ariel Graff, MD, PhD

CONTACT

416-535-8501; ariel.graff@camh.ca

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 23, 2022
• First Posted: June 28, 2022
• Study Start: September 17, 2021
• Primary Completion: March 31, 2026
• Study Completion: March 31, 2026
• Last Updated: September 23, 2025

Record last verified: 2025-03

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)