SchizophreniaNCT05109065
Peripheral Immune System in Individuals With Schizophrenia
An observational study of Schizophrenia and Schizo Affective Disorder, run by Stanford University at 1 site in United States.
Trial summary
The investigators are seeking healthy volunteers and people with schizophrenia or schizoaffective disorder for a clinical study of the immune system in psychotic disorders. This is an observational study, to understand the ways in which the immune system may be contributing to the disease process. Read more about this study
- Who is it for?
- Ages 18 to 40 yearsHealthy volunteers can take part
- Conditions the study is for
- Schizophrenia, Schizo Affective Disorder, Schizophreniform Disorders
- What is being tested?
- SCID (Standardized Clinical Interview for DSM-V), PSS (Perceived Stress Score) and Urine Toxicology Screen
- How many people
- 63 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Mar 2021to 23 May 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 40 years
- All sexes
- Healthy volunteers accepted
- Adult
Study population: Patients seen at local outpatient clinics for schizophrenia, local community residents, and volunteers on clinical study database.
Who may be able to join
- No known diagnosis of schizophrenia or schizoaffective disorder
- No history of depression, anxiety, bipolar disorder, PTSD, agoraphobia, panic disorder, or generalized anxiety disorder
- Negative assessment for psychotic symptoms on day of interview
Who cannot join
- Participants have a history of bleeding disorders or are taking blood thinners.
- Participants have a history of epilepsy, known genetic disorders
- Immunocompromised state (eg., receiving immunosuppressive therapy, transplant).
- History of brain-related disease (eg., stroke)
- Any uncontrolled medical disorder such as cancer.
- History of substance abuse or positive urine toxicology screen (including test for marijuana) on the day of the blood draw
Trial locations and contacts
1 site in 1 country.
United States1 site
Stanford University School of Medicine
Stanford, California, 94704
About this study
The investigators are seeking healthy volunteers and people with schizophrenia or schizoaffective disorder for a clinical study of the immune system in psychotic disorders. This is an observational study, to understand the ways in which the immune system may be contributing to the disease process.
Read the detailed description
Genetic studies have linked the number of copies coding for C4 protein to risk for schizophrenia. Studies examining the amount of mRNA, the molecules that point to how much C4 protein is likely being made, found more C4 mRNA in the brains from individuals with schizophrenia. Studies in mice have suggested that expressing more C4 protein in the brain, specifically the A-type of C4, can result in abnormalities in behavior. However, researchers have also found that pathways that involve this protein in the blood to be abnormal in individuals even before they develop schizophrenia and hypothesize these abnormalities change the blood brain barrier. In this work, the researchers are hoping to understand the ways in which C4 protein is abnormal in the peripheral blood and how this may be contributing to the disease process in hopes of finding new ways of helping individuals with schizophrenia and possibly other mental health disorders. A major goal of this study is to collect blood tissue for ongoing translational study of pathophysiological mechanisms of schizophrenia.
Interested participants will be asked a series of questions about their medical and mental health history, be able to provide informed consent, undergo a urine toxicology screen and be willing to provide a blood sample.
- Being tested
- SCID (Standardized Clinical Interview for DSM-V), PSS (Perceived Stress Score), Urine Toxicology Screen, Vitals, Blood Work
- Keywords
- psychosis, psychiatry, complement immune system
- Medical subject headings
- Schizophrenia, Psychotic Disorders
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SCID (Standardized Clinical Interview for DSM-V)Diagnostic test
The Structured Clinical Interview for DSM-5 (SCID-5) is a semistructured interview guide for a clinician or trained mental health professional to diagnose major mental illnesses.
PSS (Perceived Stress Score)Diagnostic test
The Perceived Stress Scale (PSS) is the most widely used psychological instrument for measuring the perception of stress. It is a measure of the degree to which situations in one's life are appraised as stressful. Items were designed to tap how unpredictable, uncontrollable, and overloaded respondents find their lives. Demographic information will also be collected.
Urine Toxicology ScreenDiagnostic test
Participants will be asked to provide a urine sample. Evidence of active substance abuse (marijuana, opioids, other non-prescription drugs) by the urine toxicology screen will disqualify participants from the study.
VitalsDiagnostic test
Height and weight will be measured in order to calculate BMI.
Blood WorkDiagnostic test
A venipuncture will be performed for the purpose of collecting blood tissue for study.
PQ-BDiagnostic test
The Prodromal Questionnaire - Brief Version (PQ-B) is a self-report measure designed to identify people who may be experiencing psychotic symptoms when they do not have a schizophrenia diagnosis.
COVID ScreeningDiagnostic test
Questionnaire to assess risk of transmission of COVID-19.
Positive and Negative Syndrome Scale (PANSS)Diagnostic test
Instrument that is completed by clinical interviewer to measure symptom severity in individuals with psychotic disorders.
| Study group | Role | What they receive |
|---|---|---|
| Individuals with primary psychotic disorders | Participants who have received any of the following diagnoses: schizophrenia, schizoaffective disorder, or schizophreniform disorder.
Participants will have urine toxicology screen, vitals recorded, and blood drawn in a single visit. Receives: Diagnostic Test: SCID (Standardized Clinical Interview for DSM-V); Diagnostic Test: PSS (Perceived Stress Score); Diagnostic Test: Urine Toxicology Screen; Diagnostic Test: Vitals; Diagnostic Test: Blood Work; Diagnostic Test: COVID Screening; Diagnostic Test: Positive and Negative Syndrome Scale (PANSS) | |
| Healthy Controls | Healthy participants who do not have any exclusion criteria will undergo an assessment to confirm absence of psychiatric disorder.
Participants will have urine toxicology screen, vitals recorded, and blood drawn in a single visit. Receives: Diagnostic Test: SCID (Standardized Clinical Interview for DSM-V); Diagnostic Test: PSS (Perceived Stress Score); Diagnostic Test: Urine Toxicology Screen; Diagnostic Test: Vitals; Diagnostic Test: Blood Work; Diagnostic Test: PQ-B; Diagnostic Test: COVID Screening |
What is being measured
The primary outcome is the main question the study is designed to answer.
Group comparison of C4 protein in immune cells
Measure the concentration of complement 4 protein in immune cells.
Measured: Day 1
Secondary outcomes (5)
Body Mass Index and its relationship to C4 protein concentration
The relationship between body mass index, calculated from the measured height and weight of participants, and the primary outcome (C4 protein concentration) will be determined.
Measured: Day 1
C4 Gene Copy Number
Determine the C4 Gene Copy Number its relationship to C4 protein concentration in immune cells.
Measured: Day 1
C4 Activation
Measure activity of C4 protein and its relationship to the primary outcome.
Measured: Day 1
Relationship to symptom presentation
Explore the relationship between clinical severity scores (PANSS) and the primary outcome.
Measured: Day 1
Relationship to stress
Explore the relationship between perceived stress (PSS) and the primary outcome.
Measured: Day 1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Nov 2021
- Study start1 Mar 2021
- Primary completion23 May 2024
- Study completion23 May 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for SchizophreniaStudies of the same condition, open and under way.
- More trials run by Stanford UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 63 participants (actual)
Sponsor and investigators
- Lead sponsor
- Stanford University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Agnieszka Kalinowski, Stanford University
- Investigators
- Agnieszka Kalinowski, MD PhD, Principal investigator, Clinical Assistant Professor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05109065
- Sponsor's protocol ID
- 58926
- Status last verified
- Jun 2025
- First submitted
- 26 Oct 2021
- Last updated
- 6 Jun 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: No plan.
Publications
Kalinowski A, Liliental J, Anker LA, Linkovski O, Culbertson C, Hall JN, Pattni R, Sabatti C, Noordsy D, Hallmayer JF, Mellins ED, Ballon JS, O'Hara R, Levinson DF, Urban AE. Increased activation product of complement 4 protein in plasma of individuals with schizophrenia. Transl Psychiatry. 2021 Sep 22;11(1):486. doi: 10.1038/s41398-021-01583-5.
PubMed 34552056
Study at a glance
From the registry record, last updated by the sponsor on 6 Jun 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Peripheral Immune System in Individuals With Schizophrenia
- ClinicalTrials.gov ID
- NCT05109065
- Acronym / sponsor ID
- 58926
- Keywords
- psychosis, psychiatry, complement immune system
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 63 participants (actual)
- Lead sponsor
- Stanford UniversityUniversity, hospital or other
- Study start
- 1 Mar 2021 (actual)
- Primary completion
- 23 May 2024 (actual)
- Study completion
- 23 May 2024 (actual)
- First posted
- 5 Nov 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The investigators are seeking healthy volunteers and people with schizophrenia or schizoaffective disorder for a clinical study of the immune system in psychotic disorders. This is an observational study, to understand the ways in which the immune system may be contributing to the disease process.
Detailed description
Genetic studies have linked the number of copies coding for C4 protein to risk for schizophrenia. Studies examining the amount of mRNA, the molecules that point to how much C4 protein is likely being made, found more C4 mRNA in the brains from individuals with schizophrenia. Studies in mice have suggested that expressing more C4 protein in the brain, specifically the A-type of C4, can result in abnormalities in behavior. However, researchers have also found that pathways that involve this protein in the blood to be abnormal in individuals even before they develop schizophrenia and hypothesize these abnormalities change the blood brain barrier. In this work, the researchers are hoping to understand the ways in which C4 protein is abnormal in the peripheral blood and how this may be contributing to the disease process in hopes of finding new ways of helping individuals with schizophrenia and possibly other mental health disorders. A major goal of this study is to collect blood tissue for ongoing translational study of pathophysiological mechanisms of schizophrenia.
Interested participants will be asked a series of questions about their medical and mental health history, be able to provide informed consent, undergo a urine toxicology screen and be willing to provide a blood sample.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Individuals with primary psychotic disorders | – | Diagnostic Test: SCID (Standardized Clinical Interview for DSM-V), Diagnostic Test: PSS (Perceived Stress Score), Diagnostic Test: Urine Toxicology Screen, Diagnostic Test: Vitals, Diagnostic Test: Blood Work, Diagnostic Test: COVID Screening, Diagnostic Test: Positive and Negative Syndrome Scale (PANSS)Participants who have received any of the following diagnoses: schizophrenia, schizoaffective disorder, or schizophreniform disorder. Participants will have urine toxicology screen, vitals recorded, and blood drawn in a single visit. |
| Healthy Controls | – | Diagnostic Test: SCID (Standardized Clinical Interview for DSM-V), Diagnostic Test: PSS (Perceived Stress Score), Diagnostic Test: Urine Toxicology Screen, Diagnostic Test: Vitals, Diagnostic Test: Blood Work, Diagnostic Test: PQ-B, Diagnostic Test: COVID ScreeningHealthy participants who do not have any exclusion criteria will undergo an assessment to confirm absence of psychiatric disorder. Participants will have urine toxicology screen, vitals recorded, and blood drawn in a single visit. |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- Patients seen at local outpatient clinics for schizophrenia, local community residents, and volunteers on clinical study database.
Key inclusion criteria (3 listed)
- No known diagnosis of schizophrenia or schizoaffective disorder
- No history of depression, anxiety, bipolar disorder, PTSD, agoraphobia, panic disorder, or generalized anxiety disorder
- Negative assessment for psychotic symptoms on day of interview
Key exclusion criteria (6 listed)
- Participants have a history of bleeding disorders or are taking blood thinners.
- Participants have a history of epilepsy, known genetic disorders
- Immunocompromised state (eg., receiving immunosuppressive therapy, transplant).
- History of brain-related disease (eg., stroke)
- Any uncontrolled medical disorder such as cancer.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| SCID (Standardized Clinical Interview for DSM-V)The Structured Clinical Interview for DSM-5 (SCID-5) is a semistructured interview guide for a clinician or trained mental health professional to diagnose major mental illnesses. | Diagnostic test | Healthy Controls, Individuals with primary psychotic disorders |
| PSS (Perceived Stress Score)The Perceived Stress Scale (PSS) is the most widely used psychological instrument for measuring the perception of stress. It is a measure of the degree to which situations in one's life are appraised as stressful. Items were designed to tap how unpredictable, uncontrollable, and overloaded respondents find their lives. Demographic information will also be collected. | Diagnostic test | Healthy Controls, Individuals with primary psychotic disorders |
| Urine Toxicology ScreenParticipants will be asked to provide a urine sample. Evidence of active substance abuse (marijuana, opioids, other non-prescription drugs) by the urine toxicology screen will disqualify participants from the study. | Diagnostic test | Healthy Controls, Individuals with primary psychotic disorders |
| VitalsHeight and weight will be measured in order to calculate BMI. | Diagnostic test | Healthy Controls, Individuals with primary psychotic disorders |
| Blood WorkA venipuncture will be performed for the purpose of collecting blood tissue for study. | Diagnostic test | Healthy Controls, Individuals with primary psychotic disorders |
| PQ-BThe Prodromal Questionnaire - Brief Version (PQ-B) is a self-report measure designed to identify people who may be experiencing psychotic symptoms when they do not have a schizophrenia diagnosis. | Diagnostic test | Healthy Controls |
| COVID ScreeningQuestionnaire to assess risk of transmission of COVID-19. | Diagnostic test | Healthy Controls, Individuals with primary psychotic disorders |
| Positive and Negative Syndrome Scale (PANSS)Instrument that is completed by clinical interviewer to measure symptom severity in individuals with psychotic disorders. | Diagnostic test | Individuals with primary psychotic disorders |
Primary outcome
Group comparison of C4 protein in immune cells
Time frame: Day 1
Measure the concentration of complement 4 protein in immune cells.
5 secondary outcomes
Body Mass Index and its relationship to C4 protein concentration
Time frame: Day 1
C4 Gene Copy Number
Time frame: Day 1
C4 Activation
Time frame: Day 1
Relationship to symptom presentation
Time frame: Day 1
Relationship to stress
Time frame: Day 1
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Jun 2025.
- Background: PubMed 34552056Kalinowski A, Liliental J, Anker LA, Linkovski O, Culbertson C, Hall JN, Pattni R, Sabatti C, Noordsy D, Hallmayer JF, Mellins ED, Ballon JS, O'Hara R, Levinson DF, Urban AE. Increased activation product of complement 4 protein in plasma of individuals with schizophrenia. Transl Psychiatry. 2021 Sep 22;11(1):486. doi: 10.1038/s41398-021-01583-5.
- Laskaris, et.al. Schizophr Res . 2019 Feb;204:30-37.Link provided by the sponsor.
- Yilmaz, et. al. Nat Neurosci . 2021 Feb;24(2):214-224.Link provided by the sponsor.
- Sekar, at al. Nature . 2016 Feb 11;530(7589):177-83.Link provided by the sponsor.
- Radhakrishnan, et al. Mol Psychiatry . 2021 Jun 16.Link provided by the sponsor.
- Onwordi, et. al. Transl Psychiatry . 2021 Jul 17;11(1):393.Link provided by the sponsor.
- Onwordi, et. al. Nat Commun . 2020 Jan 14;11(1):246.Link provided by the sponsor.
- Individual participant dataSharing planned: No. No plan.
Related trials for Schizophrenia
RecruitingPhase 2
Study to Evaluate the Safety and Efficacy of Ublituximab in Participants With Schizophrenia
Schizophrenia
RecruitingPhase 3
Relapse Prevention Trial Evaluating KarXT Treatment in Schizophrenia
Schizophrenia
Recruiting
Magnetic Seizure Therapy for Schizophrenia - Trial
Treatment Resistant Schizophrenia, Schizophrenia
Recruiting
Developing Biomarker-Supported Schizophrenia Spectrum Disorder (SSD) Prevention
Schizophrenia Spectrum Disorders (SSD)
RecruitingObservational study
Sensory Profile and Early Clinical Signs of Calm Room Users
Psychotic Disorders, Personality Disorders
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Agnieszka Kalinowski, MD PhD principal investigator
Clinical Assistant Professor
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Schizophrenia and Schizo Affective Disorder, run by Stanford University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Jun 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Group comparison of C4 protein in immune cells (time frame: Day 1). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05109065, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Jun 2025.