Testing Intranasal insulin for schizophrenia
Official title: Does Abnormal Insulin Action in the Brain Underlie Cognitive and Metabolic Dysfunction in Schizophrenia
Interventions
Intranasal insulin
160 IU insulin (Humalog) is administered intranasally using a metered spray bottle 15 minutes prior to the PET scan.
Placebo
0.9% saline is administered intranasally using a metered spray bottle 15 minutes prior to the PET scan.
Canadian Sites (1)
Centre for Addiction and Mental Health
Toronto, Ontario, Canada
Eligibility Criteria
See who this study is looking for31 criteria
The trial’s own eligibility text, word for word from the registry. Only the trial site can say who takes part.
Inclusion
- +17-45 years
- +17-45 years of age
- +i) Experimental group (participants with a diagnosis of schizophrenia spectrum disorder):
- +both sexes;
- +Patients with first-episode schizophrenia spectrum illness: Primary DSM-5 diagnosis of schizophrenia, schizoaffective disorder, schizophreniform disorder, delusional disorder, brief psychotic disorder, psychotic disorder NOS, major depressive disorder with psychotic symptoms, bipolar I disorder, and bipolar II disorder, OR substance-induced psychosis, and antipsychotic treatment for schizophrenia, schizoaffective disorder, or other specified schizophrenia spectrum, other psychotic disorder, major depressive disorder with psychotic symptoms, bipolar I disorder, and bipolar II. (Diagnosis willbe confirmed via CAMH chart review).
- +BMI under or equal to 27
- +ii) Control groupControl groupThe group a new treatment is measured against.Read more → (healthy controls):
- +hand dominance -and
- +body mass index (BMI)-matched
- +Absence of DSM-5 diagnosis other than a specific phobia according to MINI
Exclusion
- −moderate or severe substance use according to MINI (per PIPrincipal investigatorThe doctor or researcher responsible for running the study at a site.Read more → discretion in the case of moderate alcohol or cannabis use)
- −prediabetes, diabetes, or evidence of impaired glucose tolerance on screeningScreeningThe checks done before joining, to see whether a study fits.Read more → OGTT
- −acute suicidal risk
- −use of weight, lipid, antidiabetic or blood pressure reducing agents
- −liver or kidney disease
- −pacemakers
- −metallic cardiac valves
- −magnetic material such as surgical clips, implanted electronic infusion pumps or any other conditions that would preclude the MRI scan
- −clinically significant claustrophobia (determined from MRI screening form; significance evaluated as per QI's discretion).
- −history of head trauma resulting in loss of consciousness \> 30 minutes that required medical attention;
- −size of head, neck, precluding to fit in the MRI or PET scanners
- −weight over 350lbs (limit for MRI scanner bed)
- −unstable physical illness
- −significant neurological disorder including a seizure disorder;
- −Completed more than 6 PET scans/ lifetime, that, together with the PET scanning procedures under this protocolProtocolThe detailed plan a study must follow.Read more → will bring the total number of PET scans to more than the allowed/lifetime (8 PET scans per lifetime). These limits are set by the Centre for Addiction and Mental Health Brain Health Imaging Centre Guideline.
- −clinically relevant abnormality observed in medical history,
- −current intake of any medication that may interfere with participation in the study or may confound the results of PET imaging (e.g. anti-diabetic medication).
- −Disorders of coagulation, blood or ongoing use of anticoagulant medication
- −Control groupControl groupThe group a new treatment is measured against.Read more →: Exclusionary criteria are as listed above for participants, in addition to:
- −\) First degree family member with primary psychotic disorder.
- −Received maximum allowed radiation in the past 12 months (20 mSv)
In plain language
Assembled directly from this trial’s registry record. Every sentence traces to a field below — nothing here is generated or interpreted.
What this study is
This study is investigating how something functions in the body, rather than testing a treatment directly.
This study is not organised into the usual phase numbers — that is common for device, behavioural, and diagnostic research.
What is being given or done in this study: Intranasal insulin, PlaceboPlaceboA dummy treatment with no active medicine, used for comparison.Read more →.
From the trial registry
Built from these fields:
- designModule.designInfo.primaryPurpose
- designModule.phases
- armsInterventionsModule.interventions[].name
How the study is run
Which group you would be placed in is decided by chance, like a coin flip — not by you and not by your doctor.
One group of people involved — usually the participants — is not told which treatment is which.
From the trial registry
Built from these fields:
- designModule.designInfo.allocation
- designModule.designInfo.maskingInfo.masking
Is there a placebo?
This study does not list a placeboPlaceboA dummy treatment with no active medicine, used for comparison.Read more → group.
There are 2 groups in this study.
From the trial registry
Built from this field:
- armsInterventionsModule.armGroups[].type
Who the study is looking for
The study lists an age range of 17 years to 45 years.
The study is open to people of any sex.
The study accepts healthy volunteersHealthy volunteerSomeone without the condition being studied who takes part anyway.Read more → as well as people with the condition.
These are the criteria the study lists. Only the trial siteTrial siteA hospital or clinic where a study is actually run.Read more → can decide whether someone can take part.
From the trial registry
Built from these fields:
- eligibilityModule.minimumAge
- eligibilityModule.maximumAge
- eligibilityModule.sex
- eligibilityModule.healthyVolunteers
How big and how long
The study aims to enrol about 20 people.
The study is currently expected to finish around August 2026.
The main measurement is taken over: Scan duration is ~90 minutes.
From the trial registry
Built from these fields:
- designModule.enrollmentInfo.count
- statusModule.completionDateStruct.date
- outcomesModule.primaryOutcomes[].timeFrame
What the study measures
[18F]-FDG brain uptake — measured over Scan duration is ~90 minutes.
From the trial registry
Built from these fields:
- outcomesModule.primaryOutcomes[].measure
- outcomesModule.primaryOutcomes[].timeFrame
Source: NCT05748990 on ClinicalTrials.gov. The full registry text is further down this page — this summary never replaces it.
Not medical advice. What do these terms mean?
What is being tested — in plain terms
About Intranasal insulinDrug
160 IU insulin (Humalog) is administered intranasally using a metered spray bottle 15 minutes prior to the PET scan.
From the trial registry — its own words, unedited.
What a drug is here: A medicine — a chemical or small-molecule treatment — given as the thing being studied.
Read the full explanation → · in clinical review
About PlaceboDrug
0.9% saline is administered intranasally using a metered spray bottle 15 minutes prior to the PET scan.
From the trial registry — its own words, unedited.
What a drug is here: A medicine — a chemical or small-molecule treatment — given as the thing being studied.
Read the full explanation → · in clinical review
Common questions
Answered from this trial’s registry record. Where the record doesn’t say, these answers say so rather than filling the gap.
Am I eligible for this trial?
Only the trial siteTrial siteA hospital or clinic where a study is actually run.Read more → can decide whether someone can take part. Concord cannot make that determination, and neither can any tool that has not examined you.
What the study lists: an age range of 17 years to 45 years.
The full inclusionInclusion criteriaThe things you must have or be for a study to consider you.Read more → and exclusion criteriaExclusion criteriaThe things that would prevent someone from taking part.Read more → are published on this page, exactly as the study team wrote them.
The useful next step is to bring this trial to your doctor. Answering a few questions first gives them something concrete to review.
From the trial registry
- eligibilityModule.minimumAge
- eligibilityModule.maximumAge
- eligibilityModule.eligibilityCriteria
Is there a placebo?
This study does not list a placeboPlaceboA dummy treatment with no active medicine, used for comparison.Read more → group.
From the trial registry
- armsInterventionsModule.armGroups[].type
Would I know which treatment I am getting?
One group of people involved — usually the participants — is not told which treatment is which.
Which group you would be placed in is decided by chance, like a coin flip — not by you and not by your doctor.
From the trial registry
- designModule.designInfo.maskingInfo.masking
- designModule.designInfo.allocation
Who can join?
The study lists an age range of 17 years to 45 years.
It is open to people of any sex.
It accepts healthy volunteersHealthy volunteerSomeone without the condition being studied who takes part anyway.Read more → as well as people with the condition.
Only the trial siteTrial siteA hospital or clinic where a study is actually run.Read more → can confirm whether a particular person can take part.
From the trial registry
- eligibilityModule.minimumAge
- eligibilityModule.maximumAge
- eligibilityModule.sex
- eligibilityModule.healthyVolunteers
How long would this take?
The study's main measurement is taken over: Scan duration is ~90 minutes.
The study as a whole is currently expected to finish around 2026-08-01.
How long any one person takes part can differ from the study length. The study team can tell you what the schedule looks like in practice.
From the trial registry
- outcomesModule.primaryOutcomes[].timeFrame
- statusModule.completionDateStruct.date
How many people are taking part?
The study aims to enrol about 20 people.
From the trial registry
- designModule.enrollmentInfo.count
Where is this happening?
This study lists one location: Toronto, Ontario, Canada.
Sites can open and close during a study, so confirm with the team before travelling.
From the trial registry
- trial_locations
About This Trial
Cognitive impairment (such as challenges in thinking and memory) is a core aspect of schizophrenia (SCZ), contributing to disability and poor functional outcomes. Additionally, almost half of the patients with SCZ are obese, the prevalence of type 2 diabetes is 3-6 times higher, and life expectancy is lower by 15-20 years compared to the general population. This is relevant as metabolic syndrome and diabetes are both associated with worse cognition among SCZ patients. Recent work studying the relationships between metabolic health and cognition has encouraged a new way of thinking about SCZ as both a metabolic and cognitive disorder. Brain insulin is involved in several processes relevant to SCZ, and abnormal brain insulin action may help explain both cognitive and metabolic abnormalities in patients with SCZ, but this has not been examined previously. Glucose uptake in several brain regions relevant to SCZ has been shown to be partially dependent on insulin. Therefore, in this study, the researchers will measure glucose uptake in the brain using an 18F-fluorodeoxyglucose (\[18F\]-FDG) positron emission tomography (PET) scan after an intranasal insulin stimulus, and will compare this measure between patients with SCZ and healthy controls.
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See if this trial could fit youThis page is for informational purposes only and does not constitute medical advice. Clinical trial eligibility can only be determined by the trial site after proper screening. Trial information is sourced from ClinicalTrials.gov and may not reflect the most current status. Always consult your healthcare provider before making decisions about clinical trial participation.