AnxietyNCT07268729
Investigation of Pathogenic Gut Microbiota Patterns in Anxiety, Depression and Panic Disorders
An observational study of Anxiety and Panic Disorder, run by University of Toronto at 1 site in Canada.
Trial summary
This study aims to investigate the etiology of anxiety, depression, and panic disorders, providing new evidence and insights into the root causes and effective treatments, potentially offering a novel approach to achieving complete recovery. Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Anxiety, Panic Disorder, Mood Disorders
- What is being tested?
- H pylori stool test and Bacterial stool analysis
- How many people
- 500 participants
- Where
- 1 siteCanada
- Study dates
- 10 Dec 2025to 10 Feb 2026
- 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 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: The study population will consist of adult males and females aged 18 to 65 recruited from the general population and outpatient mental health clinics. Participants will include individuals with clinically confirmed anxiety, depression, or panic disorder, as well as healthy control subjects with no psychiatric history. The study will aim to include participants from diverse ethnic and cultural backgrounds to ensure broad representation of the population.
Who may be able to join
- • Adults aged 18-65 years.
- Either of the following:
- Diagnosed with anxiety, depression, or panic disorder according to DSM-5 criteria, regardless of current treatment status.
- Healthy individuals with no history of psychiatric disorders (control group).
- Able to provide informed consent and stool sample.
Who cannot join
- • Diagnosis of psychotic disorders or neurocognitive conditions.
- Use of systemic antibiotics or antifungals within the past 60 days.
Trial locations and contacts
1 site in 1 country.
About this study
This study aims to investigate the etiology of anxiety, depression, and panic disorders, providing new evidence and insights into the root causes and effective treatments, potentially offering a novel approach to achieving complete recovery.
Read the detailed description
Background: Anxiety, depression and panic disorders are among the most prevalent mental health conditions globally, affecting millions and imposing a substantial burden on individuals, families, and healthcare systems. These disorders often manifest through recurrent, severe episodes of anxiety and fear, frequently accompanied by physical symptoms such as palpitations, chest pain, and dizziness, which can lead to significant functional impairment and diminished quality of life. While current treatment options include pharmacotherapy and cognitive-behavioral therapy, response rates vary, and many patients experience residual symptoms or adverse effects, leading to high rates of treatment discontinuation. Furthermore, the growing recognition of treatment-resistant anxiety, depression and panic disorders highlights an urgent need for innovative, evidence-based therapies that provide sustained relief without compromising safety.
Introduction Anxiety, depression and panic disorders are pervasive and debilitating chronic mental health conditions, affecting approximately 20% of the global population over a lifetime. Characterized by episodes of intense fear and physical symptoms such as heart palpitations, shortness of breath, and dizziness, these disorders can severely impact daily functioning, interpersonal relationships, and overall quality of life. Individuals with these conditions are also at increased risk for comorbidities including depression, substance use disorders, and cardiovascular disease, further complicating their clinical profile and necessitating more comprehensive treatment strategies.
Despite the availability of pharmacotherapy, such as selective serotonin reuptake inhibitors (SSRIs) and benzodiazepines, alongside cognitive-behavioral therapy (CBT), there remain substantial challenges in achieving and maintaining symptom relief. Response rates vary widely, and a significant proportion of patients experience partial or inadequate relief, with some exhibiting treatment-resistant symptoms. Moreover, pharmacological treatments can be associated with side effects like weight gain, fatigue, and cognitive impairment, which may lead to discontinuation or non-adherence. These limitations highlight a critical need for alternative or adjunctive interventions that can provide more effective, sustainable, and safer outcomes.
This trial was therefore designed to assess the prevalence of pathogenic gut bacteria among patients with anxiety, depression, and panic disorder compared to healthy controls.
Objective: This study aims to investigate the etiology of anxiety, depression, and panic disorders, providing new evidence and insights into the root causes, potentially offering a novel approach to these conditions..
Findings from this study are anticipated to advance clinical understanding and treatment options for anxiety, depression and panic disorders, providing a potentially more effective approach and that provide lasting relief for patients struggling with these conditions.
- Conditions
- Anxiety, Panic Disorder, Mood Disorders, Depression
- Being tested
- H pylori stool test, Bacterial stool analysis
- Medical subject headings
- Anxiety Disorders, Panic Disorder, Mood Disorders, Depression
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
H pylori stool testDiagnostic test
Participants will provide a stool sample for noninvasive testing to detect the presence of Helicobacter pylori bacteria. The test will be performed using a validated laboratory assay that identifies H. pylori antigens in stool. Results will be used to assess potential associations between H. pylori infection, gut microbiome composition, and symptoms of anxiety or depression. The test is diagnostic only and does not involve administration of any drug or treatment.
Bacterial stool analysisDiagnostic test
Participants will provide stool samples for microbiome sequencing using a validated laboratory assay. The analysis will characterize bacterial taxa within the gut microbiome and identify potential pathogenic species. Sequencing results will be correlated with psychological assessments and clinical measures to investigate relationships between gut microbial composition and symptoms of anxiety, depression, and panic disorder.
| Study group | Role | What they receive |
|---|---|---|
| Patients under ongoing treatment | Participants in this group are adults currently receiving ongoing treatment for anxiety, depression, or panic disorder. Treatment may include prescribed medication, psychotherapy, or other clinician-supervised care. These participants will complete the same baseline psychological assessments and stool microbiome testing as the other cohorts. Their data will help evaluate how existing treatments may influence gut microbiome composition and mental-health outcomes over time. Receives: Diagnostic Test: H pylori stool test; Diagnostic Test: Bacterial stool analysis | |
| Healthy controls with no psychiatric history | Participants in this group are healthy adults with no self-reported or clinically diagnosed history of psychiatric or neurological disorders. They will complete the same baseline assessments and biological sample collection (including stool microbiome testing) as the clinical cohort, but will not receive any treatment or individualized intervention. Their data will serve as a comparison reference to help identify microbiome and biomarker patterns associated with anxiety and depression. Receives: Diagnostic Test: H pylori stool test; Diagnostic Test: Bacterial stool analysis | |
| Patients with clinically confirmed anxiety, depression, and panic disorder. | Participants in this cohort are adults with a current, clinically confirmed diagnosis of anxiety disorder, depressive disorder, or panic disorder. Each participant will provide baseline psychological assessments and biological samples, including stool microbiome testing. Based on their results, they may receive individualized lifestyle or dietary recommendations under physician supervision. Participants will be followed over time to evaluate changes in mood, stress, and biological markers related to mental-health outcomes. Receives: Diagnostic Test: H pylori stool test; Diagnostic Test: Bacterial stool analysis |
What is being measured
The primary outcome is the main question the study is designed to answer.
Presence of pathogenic gut bacteria
The presence of pathogenic bacterial species will be identified through microbiome sequencing of stool samples using a validated laboratory assay. Sequencing data will be analyzed to detect and quantify bacterial taxa associated with dysbiosis and pathogenicity within the gut microbiome. The primary outcome will be defined as the detection of one or more bacterial pathogens meeting pre-specified taxonomic or functional criteria.
Measured: Day 10 Upon receipt of stool analysis results
Secondary outcomes (1)
Symptom reduction, and eradication.
Changes in psychological symptom severity will be assessed using validated clinical instruments for anxiety, depression, and panic disorder. Composite symptom scores will be calculated and compared with baseline values to evaluate reductions in symptom severity over time. Correlations between the eradication of pathogenic gut bacteria and improvements in psychological symptoms will also be examined.
Measured: Day 0 (baseline), Day 24 (post-eradication reassessment), and Day 30 (post-eradication reassessment)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Dec 2025
- Study start10 Dec 2025
- Primary completion25 Jan 2026
- Study completion10 Feb 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AnxietyStudies of the same condition, open and under way.
- More trials run by University of TorontoThe 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
- Cohort
- Time perspective
- Prospective
- Enrolment
- 500 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Toronto
- Sponsor type
- University, hospital or other
- Collaborators
- MedBliss Research Network
- Responsible party
- Principal investigator, Hassan Kattan, University of Toronto
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07268729
- Sponsor's protocol ID
- Pro00084759
- Status last verified
- Apr 2026
- First submitted
- 18 Nov 2025
- Last updated
- 29 Apr 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared due to privacy considerations and data governance restrictions related to identifiable microbiome and psychological data. Summary results and aggregated findings will be made publicly available through publication and ClinicalTrials.gov reporting.
Study at a glance
From the registry record, last updated by the sponsor on 29 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Investigation of Pathogenic Gut Microbiota Patterns in Anxiety, Depression and Panic Disorders
- ClinicalTrials.gov ID
- NCT07268729
- Acronym / sponsor ID
- Pro00084759
- Conditions
- Anxiety, Panic Disorder, Mood Disorders, Depression
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 500 participants (actual)
- Lead sponsor
- University of TorontoUniversity, hospital or other
- Collaborators
- MedBliss Research Network
- Study start
- 10 Dec 2025 (actual)
- Primary completion
- 25 Jan 2026 (actual)
- Study completion
- 10 Feb 2026 (actual)
- First posted
- 8 Dec 2025 (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.
This study aims to investigate the etiology of anxiety, depression, and panic disorders, providing new evidence and insights into the root causes and effective treatments, potentially offering a novel approach to achieving complete recovery.
Detailed description
Background: Anxiety, depression and panic disorders are among the most prevalent mental health conditions globally, affecting millions and imposing a substantial burden on individuals, families, and healthcare systems. These disorders often manifest through recurrent, severe episodes of anxiety and fear, frequently accompanied by physical symptoms such as palpitations, chest pain, and dizziness, which can lead to significant functional impairment and diminished quality of life. While current treatment options include pharmacotherapy and cognitive-behavioral therapy, response rates vary, and many patients experience residual symptoms or adverse effects, leading to high rates of treatment discontinuation. Furthermore, the growing recognition of treatment-resistant anxiety, depression and panic disorders highlights an urgent need for innovative, evidence-based therapies that provide sustained relief without compromising safety.
Introduction Anxiety, depression and panic disorders are pervasive and debilitating chronic mental health conditions, affecting approximately 20% of the global population over a lifetime. Characterized by episodes of intense fear and physical symptoms such as heart palpitations, shortness of breath, and dizziness, these disorders can severely impact daily functioning, interpersonal relationships, and overall quality of life. Individuals with these conditions are also at increased risk for comorbidities including depression, substance use disorders, and cardiovascular disease, further complicating their clinical profile and necessitating more comprehensive treatment strategies.
Despite the availability of pharmacotherapy, such as selective serotonin reuptake inhibitors (SSRIs) and benzodiazepines, alongside cognitive-behavioral therapy (CBT), there remain substantial challenges in achieving and maintaining symptom relief. Response rates vary widely, and a significant proportion of patients experience partial or inadequate relief, with some exhibiting treatment-resistant symptoms. Moreover, pharmacological treatments can be associated with side effects like weight gain, fatigue, and cognitive impairment, which may lead to discontinuation or non-adherence. These limitations highlight a critical need for alternative or adjunctive interventions that can provide more effective, sustainable, and safer outcomes.
This trial was therefore designed to assess the prevalence of pathogenic gut bacteria among patients with anxiety, depression, and panic disorder compared to healthy controls.
Objective: This study aims to investigate the etiology of anxiety, depression, and panic disorders, providing new evidence and insights into the root causes, potentially offering a novel approach to these conditions..
Findings from this study are anticipated to advance clinical understanding and treatment options for anxiety, depression and panic disorders, providing a potentially more effective approach and that provide lasting relief for patients struggling with these conditions.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Patients under ongoing treatment | – | Diagnostic Test: H pylori stool test, Diagnostic Test: Bacterial stool analysisParticipants in this group are adults currently receiving ongoing treatment for anxiety, depression, or panic disorder. Treatment may include prescribed medication, psychotherapy, or other clinician-supervised care. These participants will complete the same baseline psychological assessments and stool microbiome testing as the other cohorts. Their data will help evaluate how existing treatments may influence gut microbiome composition and mental-health outcomes over time. |
| Healthy controls with no psychiatric history | – | Diagnostic Test: H pylori stool test, Diagnostic Test: Bacterial stool analysisParticipants in this group are healthy adults with no self-reported or clinically diagnosed history of psychiatric or neurological disorders. They will complete the same baseline assessments and biological sample collection (including stool microbiome testing) as the clinical cohort, but will not receive any treatment or individualized intervention. Their data will serve as a comparison reference to help identify microbiome and biomarker patterns associated with anxiety and depression. |
| Patients with clinically confirmed anxiety, depression, and panic disorder. | – | Diagnostic Test: H pylori stool test, Diagnostic Test: Bacterial stool analysisParticipants in this cohort are adults with a current, clinically confirmed diagnosis of anxiety disorder, depressive disorder, or panic disorder. Each participant will provide baseline psychological assessments and biological samples, including stool microbiome testing. Based on their results, they may receive individualized lifestyle or dietary recommendations under physician supervision. Participants will be followed over time to evaluate changes in mood, stress, and biological markers related to mental-health outcomes. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- The study population will consist of adult males and females aged 18 to 65 recruited from the general population and outpatient mental health clinics. Participants will include individuals with clinically confirmed anxiety, depression, or panic disorder, as well as healthy control subjects with no psychiatric history. The study will aim to include participants from diverse ethnic and cultural backgrounds to ensure broad representation of the population.
Key inclusion criteria (5 listed)
- • Adults aged 18-65 years.
Key exclusion criteria (2 listed)
- • Diagnosis of psychotic disorders or neurocognitive conditions.
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 |
|---|---|---|
| H pylori stool testParticipants will provide a stool sample for noninvasive testing to detect the presence of Helicobacter pylori bacteria. The test will be performed using a validated laboratory assay that identifies H. pylori antigens in stool. Results will be used to assess potential associations between H. pylori infection, gut microbiome composition, and symptoms of anxiety or depression. The test is diagnostic only and does not involve administration of any drug or treatment. | Diagnostic test | Healthy controls with no psychiatric history, Patients under ongoing treatment, Patients with clinically confirmed anxiety, depression, and panic disorder. |
| Bacterial stool analysisParticipants will provide stool samples for microbiome sequencing using a validated laboratory assay. The analysis will characterize bacterial taxa within the gut microbiome and identify potential pathogenic species. Sequencing results will be correlated with psychological assessments and clinical measures to investigate relationships between gut microbial composition and symptoms of anxiety, depression, and panic disorder. | Diagnostic test | Healthy controls with no psychiatric history, Patients under ongoing treatment, Patients with clinically confirmed anxiety, depression, and panic disorder. |
Primary outcome
Presence of pathogenic gut bacteria
Time frame: Day 10 Upon receipt of stool analysis results
The presence of pathogenic bacterial species will be identified through microbiome sequencing of stool samples using a validated laboratory assay. Sequencing data will be analyzed to detect and quantify bacterial taxa associated with dysbiosis and pathogenicity within the gut microbiome. The primary outcome will be defined as the detection of one or more bacterial pathogens meeting pre-specified taxonomic or functional criteria.
1 secondary outcome
Symptom reduction, and eradication.
Time frame: Day 0 (baseline), Day 24 (post-eradication reassessment), and Day 30 (post-eradication reassessment)
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 29 Apr 2026.
- Individual participant dataSharing planned: No. Individual participant data will not be shared due to privacy considerations and data governance restrictions related to identifiable microbiome and psychological data. Summary results and aggregated findings will be made publicly available through publication and ClinicalTrials.gov reporting.
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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.
The record lists no contact. Use the official record to reach the sponsor.
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 Anxiety and Panic Disorder, run by University of Toronto at 1 site in Canada.
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 5 inclusion and 2 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 29 Apr 2026. 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 Canada. 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?
Presence of pathogenic gut bacteria (time frame: Day 10 Upon receipt of stool analysis results). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 29 Apr 2026.