MEDBLISS RESEARCH NETWORK
Study Protocol
V3.0 May 25, 2025
Institution: MedBliss Research Network
Study Title: Investigating the Etiology of Anxiety, Depression and Panic Disorders.
Abstract
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 and panic disorders highlights an urgent need for innovative, evidence-based therapies that provide sustained relief without compromising safety.
Introduction:
Anxiety 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 anxiety and panic disorders are also at increased risk for comorbid conditions, 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 to these standard treatments 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.
Despite its prevalence, the exact etiology of anxiety, depression and panic disorder remained unclear. This underscores the need for a more comprehensive understanding of the underlying mechanisms of anxiety and the development of more effective treatments.
The current study aims to investigate the etiology of anxiety, depression and panic disorders, and address gaps in existing treatments for anxiety and panic disorders. Findings from this study are anticipated to advance clinical understanding and treatment options for anxiety and panic disorders, providing a potentially more effective approach and novel treatments that provide lasting relief for patients struggling with these conditions.
Objectives:
This study aims to investigate the etiology of anxiety depression and panic disorders, providing new evidence and insights into the root causes of these disorders, potentially offering a novel approach to achieving complete recovery for patients.
To investigate the prevalence of pathogenic gut bacteria in individuals diagnosed with anxiety, depression, and panic disorder, and to explore their potential link to these conditions.
Methods
Given the double-blind design, the placebo effect
is minimized, ensuring that the observed treatment effects are due to the intervention itself and not influenced by participant or researcher expectations. A control group is administered a placebo identical in appearance to the active treatment. This control group will allow for a comparative analysis of treatment efficacy while accounting for potential placebo effects.
Study Design: Randomized, double-blind, placebo-controlled trial.
Participant Enrollment: 3,150 participants aged 18-65 years.
Intervention: Participants will receive either a placebo, or antibiotic treatment, and natural gut detoxification therapy.
Primary Outcome: eradication of anxiety depression and panic disorder symptoms.
Secondary Outcomes: Quality of life improvements, microbiome changes, and adverse event monitoring.
Statistical Analysis: Chi-square tests and logistic regression will be applied, with significance set at p < 0.001.
Study Procedures
This clinical trial follows a rigorous, double-blind, placebo-controlled design to minimize bias and ensure the integrity of collected data.
Randomization Scheme:
Participants will be randomly assigned in a 1:1 ratio to the intervention or control group using computer-generated randomization blocks stratified by age (18–39, 40–59, 60–80) and gender. The randomization sequence will be generated by a third-party biostatistician and implemented via an electronic allocation system accessible only to the study pharmacist.
Blinding Procedures: The study is fully double-blinded. Identical encapsulation of active drug and placebo ensures that neither participants nor investigators know the group assignments. Emergency unblinding procedures are in place if required for clinical safety.
Detailed Visit Schedule:
- Visit 1 (Week 0): Informed consent, screening labs, diagnostic confirmation, baseline scoring (HAM-A, PHQ-9, PDSS, SF-36), stool sample collection.- Visits 2–5 (Weeks 1–4): Weekly study drug administration, compliance check, symptom reassessment, AE/SAE monitoring.
- Visit 6 (Week 6): Post-treatment assessments (all psychiatric and microbiome metrics).
- Visit 7 (Week 8): Final follow-up assessments and study exit procedures.
Study Treatment Details:
- Intervention Arm: Antibiotic therapy (e.g., Drug A 500mg + Drug B 250mg twice daily for 10 days), followed by 30 days of gut detoxification and a daily 25 billion CFU probiotic capsule.- Control Arm: Matching placebo capsules administered on the same schedule.
Monitoring:
All assessments and drug administrations will be supervised by GCP-certified clinicians. Adherence will be tracked by pill counts and electronic diaries.
Subject Selection
Recruitment Strategy:
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Recruitment Plan: Recruitment will be conducted through a combination of community outreach, online platforms, and referrals from healthcare professionals. Potential participants will be identified through clinics and social media campaigns targeting
individuals experiencing anxiety, depression, or panic disorders.
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Inclusion and Exclusion Criteria: - Inclusion Criteria:
- Age range: 18-80 years
- Diagnosed with anxiety, depression, or panic disorder as per DSM-5 criteria
- Willing to provide informed consent (or parental consent for minors)
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Exclusion Criteria:
- Comorbid psychiatric conditions requiring immediate intervention (e.g., psychosis) - Ongoing medication that may interfere with study outcomes
- History of antibiotic resistance or severe allergic reactions to antibiotics
Screening Process: Initial pre-screening will be conducted online. Eligible respondents will undergo a structured clinical interview by a licensed professional using DSM-5 criteria to confirm diagnosis.
Risk/Safety Information
Anticipated Risks:
- Mild to moderate gastrointestinal side effects (nausea, diarrhea) - Allergic reactions to antibiotics (rash, itching, anaphylaxis—rare)
- Temporary alterations in microbiome balance
Risk Mitigation Measures:
- Pre-screening for allergy history and contraindications - Probiotic regimen to reduce microbiota disruption
- AE monitoring at every visit and 24/7 access to study nurse hotline
Safety Review Plan:
A Data Safety Monitoring Board (DSMB) will conduct interim safety analyses after every 500 participants enrolled. Investigators will file SAE reports to the IRB within 24 hours.
Subject Data Protection
Data Confidentiality Measures: All identifiable participant data will be replaced with a unique ID code. The key linking ID to identity will be stored in a separate encrypted file accessible only to the PI.
Storage and Access:
- Electronic records stored on encrypted, HIPAA-compliant servers with daily backups - Paper forms locked in PI office file cabinet
- Data access limited to essential study personnel, with role-based permissions
Regulatory Compliance: The study conforms to HIPAA, 21 CFR Part 11, and GDPR standards. System access will be logged and audited quarterly by the data manager. De-identified data may be used in secondary analyses or published upon IRB approval.
Ethical Considerations:
The study will adhere to the Declaration of Helsinki and will be reviewed by the IRB beforerecruitment begins.
Informed consent will be obtained from all participants.
Data privacy and participant confidentiality will be strictly maintained.
Expected Impact:
This study aims to provide scientific evidence supporting the role of the gut-brain axis in anxiety disorders and depression potentially introduce a novel treatment approach focused on bacterioal modulation, and detoxification.
Study Procedures
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Informed Consent Process: Informed consent will be obtained at the first visit, prior to any study procedures. Participants will be given detailed information about the study's purpose, procedures, potential risks, and benefits. Parental consent will be obtained for participants under 18 years of age.
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Duration of Study Participation: Participants will be involved in the study for approximately
2 months, including a treatment period and a follow-up.
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Detailed Visit-by-Visit Procedures: - Visit 1: Screening, Consent, and Baseline Assessment
- Visit 2-5: Intervention Sessions (Antibiotic or Placebo Administration)
- Visit 6: Post-Treatment Assessment
- Visit 7: Follow-Up Assessment
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Study Treatment Administration: The study will administer targeted antibiotics or placebo. Dosages will be determined based on individual body weight and health status.
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Cost Responsibilities: Participants will not incur any costs. All study-related procedures and treatments will be covered by the Sponsor.
Risk/Safety Information
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Expected Risks: -
Rare Gastrointestinal discomfort (e.g., diarrhea) from antibiotic use - Possible allergic reactions to antibiotics
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Risk Mitigation Strategies: - Pre-screening for antibiotic allergies
- Close monitoring of side effects with prompt intervention if needed - Provision of probiotics to maintain gut health during and post-treatment
Monitoring/Reporting of AE/SAE
- Definitions: - Adverse Event (AE): Any undesirable experience occurring during the study period, regardless of its relation to the study intervention.
- Serious Adverse Event (SAE): An event that results in hospitalization, significant disability, or death.
- Monitoring Responsibilities:
A dedicated safety monitoring team will oversee all AEs and SAEs.
- Data Collection and Reporting:
- Participants will report any adverse events during each visit or via a 24/7 helpline.
- The safety monitoring team will review and report AEs/SAEs to the IRB and Sponsor within 24-48 hours.
Study Oversight
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Early Termination Conditions: The study may be terminated early due to significant safety concerns, lack of efficacy, or Sponsor's discretion.
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Decision-Maker Responsibilities: The Principal Investigator and Sponsor will jointly make early termination decisions.
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Data Access for Monitoring: Study data will be made available for monitoring, auditing, IRB review, and regulatory inspection, ensuring compliance with Good Clinical Practice (GCP) guidelines.
Data Analysis
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Planned Analysis: - Chi-square tests for categorical variables (e.g., symptom resolution rates)
- Logistic regression to assess predictors of treatment response
- Significance threshold set at p < 0.001
IRB Review/Ethics/Informed Consent
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Ethical Considerations: The study will comply with the Declaration of Helsinki and Good Clinical Practice (GCP) guidelines.
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Informed Consent Details: Informed consent will be obtained before any study procedures, ensuring participants understand the study's purpose, risks, and benefits.
Confidentiality
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Data Handling and Storage: - All study data will be de-identified and stored in encrypted digital databases.
- Access to the data will be restricted to authorized personnel only.
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Confidentiality Measures: - Data will be anonymized using unique participant codes.
- No identifiable information will be published or shared outside the study team.
Intended Use of the Data
- Purpose and Objectives Alignment: Data collected will be used to evaluate the efficacy and safety of the novel therapeutic intervention for anxiety, depression, and panic disorders.
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Scientific Contribution: The findings aim to contribute to the scientific understanding of the gut-brain axis in anxiety disorders and support the development of new therapeutic approaches.
Study Purpose and Objectives (Expanded)
This clinical trial is designed to investigate the role of gut microbiota—particularly pathogenic bacteria—in the development and persistence of anxiety, depression, and panic disorders. The primary objective is to evaluate the potential link between pathogenic gut bacteria and the onset of these psychiatric symptoms
- Primary Endpoint: Complete remission or clinically significant reduction in anxiety, depression, and panic disorder symptoms, as measured by standardized scales (e.g., HAM-A, PHQ-9, and PDSS).
- Secondary Endpoints: Improvements in quality of life (SF-36), changes in specific gut bacteria identified by metagenomic analysis, and incidence of adverse events.
Randomization and Blinding Details
Participants will be randomized in a 1:1 ratio into either the intervention or placebo group using a computer-generated randomization list. Randomization will be stratified by age and sex to ensure balanced distribution across groups.
Double-blinding will be implemented. Participants, investigators, and study staff involved in outcome assessments will be blinded to group allocation. The placebo will be visually indistinguishable from the active antibiotic treatment.
Data Collection Methods
Standardized and validated tools will be used to assess psychiatric symptoms and quality of life at baseline, during treatment, and follow-up.
- HAM-A (Hamilton Anxiety Rating Scale)
- PHQ-9 (Patient Health Questionnaire for Depression)
- PDSS (Panic Disorder Severity Scale)
- SF-36 (Short Form Health Survey)
Stool samples will be collected at baseline, post-treatment, and follow-up to assess microbiome changes.
Data Monitoring Committee (DMC)
A Data Monitoring Committee (DMC) has been established for this study to provide independent oversight of participant safety and to ensure the integrity of the study data. The committee comprises a multidisciplinary team with relevant expertise to support comprehensive monitoring and objective decision-making.
The DMC Responsibilities:
•Monitoring Participant Safety: Reviewing adverse events and safety data to ensure participant well-being.
•Assessing Efficacy Data: Evaluating interim results to determine the study’s effectiveness.
•Maintaining Study Integrity: Protecting the blinding and integrity of the study design.
•Stopping Rules and Recommendations: Making recommendations on early study termination, modifications, or continuation based on safety and efficacy data.
•Reporting to IRB and Investigators: Providing independent assessments and recommendations to the Principal Investigator and notifying the IRB of any significant findings.
DMC Meeting Schedule
The DMC will meet:
•weekly during the active enrollment and data collection phases.
•Ad-hoc Meetings will be called if serious adverse events (SAEs) or other significant safety concerns arise.
•Final Review will occur at the end of data collection before the study’s conclusion.
DMC Reporting
•Reports will be sent to the Principal Investigator and Study Sponsor.
•Urgent safety concerns will be communicated immediately via email and followed up with a formal report.
Stopping Rules for this Research Study:
The study will be stopped or modified if:
•Unacceptable Safety Risk: There is evidence of serious adverse events that outweigh potential benefits.
•Lack of Efficacy: Interim analysis shows no significant improvement compared to the control group.
•Ethical Concerns: Any ethical issues arise that compromise participant safety or the integrity of the study.
•Significant Efficacy: If overwhelming efficacy is observed, the study may be stopped early to offer the intervention to all participants.
•External Factors: Such as new safety information from other studies or regulatory authorities.
Subject Data Protection
All participant data will be coded with unique identifiers. Personal information will be stored separately from study data in secure, encrypted files with restricted access.
Electronic Case Report Forms (eCRFs) will be used for data entry. Access to eCRFs will be role-based and monitored by an audit trail. Data will be stored on secure servers compliant with HIPAA and 21 CFR Part 11.
1. Study Sample Size Justification
The proposed sample size is 350-500 participants.
2. Target Population Characteristics
Participants will be adults aged 18–65 years diagnosed with moderate to severe generalized anxiety disorder (GAD), panic disorder, or major depressive disorder according to DSM-5 criteria. Inclusion requires a history of symptom persistence for at least six months, with or without previous treatment. Both treatment-naïve individuals and those with a partial or unsatisfactory response to prior therapy (e.g., SSRIs, benzodiazepines, CBT) will be eligible. This reflects real-world clinical heterogeneity and supports generalizability of findings.
3. Choice of Antibiotic(s) and Probiotic(s)
The antibiotic regimens were selected based on clinical identification of gut pathogens commonly found in individuals with anxiety, depression, and panic disorders, as well as long-term observational data on symptom resolution following targeted eradication. The antibiotics used are:
- HP-PAC: A combination of lansoprazole, clarithromycin, and amoxicillin, indicated for Helicobacter pylori eradication.- Cefuroxime axetil 500 mg: A broad-spectrum cephalosporin effective against a range of Gram-positive and Gram-negative bacteria.
- Clindamycin 300 mg: Selected for its targeted efficacy against alpha-hemolytic streptococcus.
These antibiotics are administered based on the participant’s detected pathogens (as determined by stool or saliva testing).
The probiotic formulation contains Lactobacillus rhamnosus and Bifidobacterium longum, chosen for their:- Anti-inflammatory and anxiolytic effects,
- Resilience following antibiotic therapy,
- Documented modulation of GABA receptor expression.
This stepwise regimen supports microbial rebalancing after pathogenic clearance.
4. Dosing and Duration of Study Treatment
Participants will receive the selected antibiotics for 10 days. During the study, concurrent use of psychotropic medications will not be permitted, except under pre-defined rescue protocols, to avoid confounding effects.
5. Study Procedures and Visit Schedule
Visit
Day
Procedures
Screening
-14 to -1
Informed consent, psychiatric interview (MINI), eligibility confirmation
Visit 1
Day 0
Baseline symptom assessments, stool sample
Visit 2
Day 10
Safety assessment, stool sample results, if pathogens present targeted antibiotics dispensation
Visit 3
Day 25
Stool sample, anxiety/depression scale reassessment
Visit 4
Day 30
Midpoint clinical assessment, safety check, detoxification, probiotics dispensing
Visit 5
Day 45
End of treatment assessment
Follow-up
Day 60
Final clinical assessment, symptom scales
6. Microbiome Knockdown Justification
The purpose of the microbiome knockdown phase is not to perform a broad reset of the gut flora, but rather to target and eliminate specific pathogenic bacteria identified in each participant through diagnostic testing (e.g., stool analysis).
Justification for Not Including a Detox-Only Arm Without Microbiome Knockdown
This study aims to investigate the potential link between pathogenic bacteria in the gut and the onset of anxiety, depression, and panic disorders. The study design is based on the hypothesis that these mental health conditions are, in part, driven by toxins and inflammatory compounds produced by specific bacterial pathogens.
Detoxification strategies alone—without first identifying and eliminating these pathogens—would fail to address the root cause of toxin production. Including a study arm that omits microbiome knockdown would therefore be biologically inconsistent with the study’s central hypothesis.
Moreover, previous clinical experience has shown that detoxification without prior targeted antibiotic therapy results in minimal or no sustained symptom improvement. Adding such an arm could also pose ethical concerns by offering a potentially ineffective intervention to participants.