---
title: Studying gut changes predicting Parkinson
nct_id: NCT07567794
status: RECRUITING
sponsor: Duke University
study_type: OBSERVATIONAL
canonical_url: "https://parkinsonspathways.com/trial/NCT07567794"
clinicaltrials_gov: "https://clinicaltrials.gov/study/NCT07567794"
last_fetched: "2026-07-31T14:00:13.172Z"
source: "Parkinson's Pathways (curated)"
---
# Studying gut changes predicting Parkinson

**Goal (in five words):** Studying gut changes predicting Parkinson

**Official Title:** Consortium for Gut-Brain Communication in Parkinson's Disease Master Protocol

**Trial ID:** [NCT07567794](https://clinicaltrials.gov/study/NCT07567794)

## Key Facts

- **Status:** RECRUITING
- **Study Type:** OBSERVATIONAL
- **Sponsor:** Duke University
- **Target Enrollment:** 250 participants
- **Start Date:** 2026-07-03
- **Completion Date:** 2028-12-31
- **Conditions:** Parkinson Disease (PD), PARKINSON DISEASE (Disorder), Gut Microbiome, Gut Microbiota, Prodromal Parkinsons Disease
- **Registry Record Last Updated:** 2026-07-31 (this month)

## Summary For Families

The goal is to find out how the nerves that connect the gut and brain are involved in Parkinson's, by comparing people with Parkinson's to people at risk and to people without the disease to spot gut-related differences that may come before or follow neurological symptoms. The approach is detailed observation: participants meet with providers, answer questionnaires, and give blood, stool, saliva, skin, and lower-colon tissue samples; they also have X-rays of swallowing and colon transit, a flexible sigmoidoscopy biopsy, and tests of rectal muscle function, with assessments repeated over a 24-month period. Adults 21 to 80 are being enrolled into three groups, people with Parkinson's (mild, moderate, or severe), people at risk such as those with a sleep disorder that causes acting out dreams plus reduced smell, and household controls without neurodegenerative disease, while people with major cognitive impairment, active inflammatory gut disease, certain bleeding risks for the sigmoidoscopy, recent cancer, or other serious medical problems are excluded.

**Estimated commitment:** Moderate commitment estimated from the protocol (based on: invasive procedure, 6 study visits). This reflects time and procedures only — confirm details with the study coordinator.

## What This Actually Involves

**Placebo** _(From the protocol)_: This is an observational study, so there is no placebo and no experimental treatment is assigned. Researchers observe and collect information while you continue your usual care.

**Visits** _(From the protocol)_: Assessments are scheduled at baseline, 6, 12, 18, and 24 months.
  > "Longitudinal design with assessments at baseline, 6, 12, 18, and 24 months"

**Procedures** _(From the protocol)_:
- Biopsy (Invasive)
  > "* have a flexible sigmoidoscopy, where a doctor looks inside the lower part of the colon and takes small tissue samples (biopsies) from the mucosa (lining)"
- Questionnaires & surveys (Non-invasive)
  > "Prodromal characteristics are defined by the MDS Research Criteria for PD and include either polysomnography (PSG)-confirmed rapid eye movement sleep behavior disorder (RBD) or possible RBD (questionnaire-based), with hyposmia as defined by the University of Pennsylvania Smell…"

**Washout** _(Ask the coordinator)_: Ask the coordinator whether you would need to stop or pause any of your current medications before or during the study (a washout period), and for how long.

**Travel & reimbursement** _(Ask the coordinator)_: Ask the coordinator whether travel, parking, or your time is reimbursed or compensated, and what is covered.

_Fields marked “From the protocol” come from the trial's registry record or quoted protocol text. Fields marked “Ask the coordinator” are not reliably available and should be confirmed directly._

## Eligibility at a Glance

Key requirements found in this trial's official criteria, in plain language. Only what the listing states is shown; the study team makes the final call.

- **Disease stage:** Stage 4 on the Hoehn and Yahr scale
- **Thinking test (MoCA):** MoCA memory and thinking score of at least 22 (criteria text: "Clinically significant cognitive impairment with a Montreal Cognitive Assessment (MOCA) score \<22")
- **Healthy volunteers:** Also accepts people without Parkinson's (healthy volunteers) (criteria text: "CT.gov structured field: healthyVolunteers")

## Do I Likely Qualify? — Self-Check Dimensions

The trial page offers an interactive self-check built from this trial's parsed criteria. It covers these dimensions; anything the criteria don't state clearly is answered "ask the study coordinator", never assumed.

- This trial enrolls people aged 21 to 80.
- This trial requires Hoehn and Yahr stage 4.
- This trial requires a MoCA thinking-test score of at least 22.

## Eligibility

- **Minimum age:** 21 Years
- **Maximum age:** 80 Years
- **Sex:** ALL

### Full Criteria

```
Inclusion Criteria (All PD Cohorts)

1. Aged ≥21 years old and ≤80 years old
2. Clinical diagnosis of PD as defined by Movement Disorder Society (MDS) PD Criteria
3. Adequate visual, hearing, cognitive, and physical ability
4. Willingness and ability to comply with scheduled visits, laboratory tests, and other study procedures. Because longitudinal participation is important to the scientific goals of the program, a "best estimate" of interest, commitment, and geographic feasibility for three years will be documented by the enrolling investigator after interview with the potential enrollee

Inclusion Criteria Controls

1. Aged ≥21 years old and ≤80 years old
2. No known or diagnosed neurodegenerative disease
3. Willingness and ability to comply with scheduled visits, laboratory tests, and other study procedures
4. Resides within the same household as person with PD

Inclusion Criteria Prodromal Cohort

1. Aged ≥21 years old and ≤80 years old
2. Prodromal characteristics are defined by the MDS Research Criteria for PD and include either polysomnography (PSG)-confirmed rapid eye movement sleep behavior disorder (RBD) or possible RBD (questionnaire-based), with hyposmia as defined by the University of Pennsylvania Smell Identification Test (UPSIT) ≤ 15th percentile.

Exclusion Criteria (All Cohorts)

1. Diagnosis of secondary or atypical parkinsonism
2. Laboratory Values:

   1. Hemoglobin (Hgb) \<10
   2. Platelets \<70,000
   3. Alanine Transaminase (ALT) or Aspartate Aminotransferase (AST) \> 2 1/2 times upper limit of normal (ULN)
   4. Moderate or severe renal disease with an estimated glomerular filtration rate (eGFR) \<60 mL/min/BSA \[body surface area\]) calculated using the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation, or moderate or severe hepatic impairment (alkaline phosphatase \[ALP\] \>2.0 times the ULN and/or total bilirubin \>2.0 times the ULN)
   5. Significantly above the normal range for PT/INR/PTT
3. Currently taking anticoagulants that are deemed exclusionary by the investigator for risk of bleeding with sigmoidoscopy procedure
4. Clinically significant cognitive impairment with a Montreal Cognitive Assessment (MOCA) score \<22
5. Clinical or laboratory findings consistent with another primary neurodegenerative disease or cognitive disorder other than PD, including but not limited to, frontotemporal lobar disease, Huntington's disease, progressive supranuclear palsy, multisystem atrophy, Creutzfeld-Jakob- Disease, Down's syndrome, cortico-basal degeneration, dementia with Lewy Bodies, Alzheimer's disease, amyotrophic lateral sclerosis, seizure disorder, stroke, or other infectious, metabolic, or systemic disease affecting the central nervous system including, but not limited to, syphilis, present hypothyroidism, present or unaddressed/treated vitamin B12 deficiency, or other screening laboratory abnormalities
6. Suicidality, defined as active suicidal thoughts or ideation within 6 months before Screening or at Baseline, defined as answering yes to items 4 or 5 on the Columbia-Suicide Severity Rating Scale (C-SSRS), or history of suicide attempt in previous 2 years, or, in the Investigator's opinion, at serious risk of suicide
7. Has cancer or has had a malignant tumor within the past 5 years. (Participants with stable untreated prostate cancer or treated/removed cutaneous carcinomas are not excluded.)
8. Any medical condition or systemic disease that, in the Investigator's opinion, may either put the participant at risk because of participation in the study, influence the results or proposed analyses, or impair the participant's ability to fully participate in the study
9. Body mass index (BMI) \>35 kg/m2 or body weight \<50 kg
10. Participant is currently pregnant, breastfeeding, and/or lactating
11. History of alcohol or substance abuse or dependence within the past 2 years (DSM IV criteria)
12. History of Covid 19 (SARS-CoV-2) infection within 6 weeks prior to screening.
13. Participants with unresolved symptoms of Covid 19 infection or ongoing cognitive or other deficits attributable to post-Covid 19 that may affect participant safety or interfere with cognitive assessments based on the Investigator's clinical judgment
14. Either ongoing or current participation in another clinical trial with an investigational agent and have taken at least one dose of study medication, unless unblinded on placebo, within 4 weeks prior to the start of screening, or five half-lives of the investigational drug, whichever is greater. The end of a previous investigational trial is the date the last dose of an investigational agent was taken. Participation in other research studies (e.g., observational studies) may be acceptable throughout this study.
15. History of GI surgery. (However, patients with appendicectomy, hemorrhoid surgery, and cholecystectomy will be eligible to participate).
16. Regular use of medication that impacts the intestinal barrier (e.g., NSAID more than 3 times weekly)
17. Has a history of Crohn's disease, ulcerative colitis, and/or other types of colitis (microscopic, lymphocytic, or collagenous colitis). Confirmed diagnosis of inflammatory bowel disease (IBD) and/or, active or uncontrolled IBD symptoms such as diarrhea, bleeding, or severe stomach pain. Treatment for IBD in the past 6 months with medicines such as steroids, biologics, or strong immune-suppressing drugs. Surgery to remove part of the bowel due to IBD. Other long-term gut diseases that cause inflammation, such as celiac disease.
```

## Locations (7)

- Stanford University, Stanford, California, United States _(37.4241, -122.1661)_
  - Marian Shahid-Besanti, MSc, (CONTACT), 650-723-0060, gutbrainresearch@stanford.edu
  - Kathleen L Poston, MD, MS, (PRINCIPAL_INVESTIGATOR)
  - Laren S Beckers, MD, (PRINCIPAL_INVESTIGATOR)
- Rush University, Chicago, Illinois, United States _(41.8500, -87.6500)_
  - Michelle Villanueva, MS, (CONTACT), 312-942-8927, michelle_villanueva@rush.edu
  - Ali Keshavarzian, MD, (PRINCIPAL_INVESTIGATOR)
  - Christopher Goetz, MD, (PRINCIPAL_INVESTIGATOR)
- University of Chicago, Chicago, Illinois, United States _(41.8500, -87.6500)_
  - Hanna Lancerio, (CONTACT), 773-633-8412, hlancerio@bsd.uchicago.edu
  - Tao Xie, MD, PhD, (PRINCIPAL_INVESTIGATOR)
  - Eugene Chang, MD, (PRINCIPAL_INVESTIGATOR)
- Massachusetts General Hospital, Boston, Massachusetts, United States _(42.3584, -71.0598)_
  - Anna Borodianski, (CONTACT), 617-724-0480, GIMotilityResearch@MGH.HARVARD.EDU
  - Aleksander Videnovic, MD, (PRINCIPAL_INVESTIGATOR)
- Mayo Clinic, Rochester, Minnesota, United States _(44.0216, -92.4699)_
  - Kelly Feuerhak, BSN, RN, CCRP, (CONTACT), 507-255-6802, rstgistudy@mayo.edu
  - Adil Bharucha, MBBS, MD, (PRINCIPAL_INVESTIGATOR)
  - Rodolfo Savica, MD, PhD, (PRINCIPAL_INVESTIGATOR)
- Columbia University, New York, New York, United States _(40.7143, -74.0060)_
  - Katharine Godfrey, (CONTACT), kb3217@cumc.columbia.edu
  - Braden Kuo, MD, (PRINCIPAL_INVESTIGATOR)
- Medical University of South Carolina, Charleston, South Carolina, United States _(32.7763, -79.9327)_
  - Stephanie N Slan, MBA, ACRP-CP, (CONTACT), slans@musc.edu

## Making Contact: How to Call This Study Site

### Who to ask for

Ask for the study coordinator. Some sites call this person the research coordinator. They are the right person for questions about joining a study. If you reach a front desk or a doctor's office scheduler, ask them to connect you with the research team for this study.

### What to say

It is fine to read this out loud, word for word:

> Hello, my name is ____. I am calling about a Parkinson's study at your site. The study number is NCT07567794. It is the one about "Studying gut changes predicting Parkinson". Could I speak with the study coordinator about taking part?

If you are calling for a family member, use their name and mention that you help with their care.

### What they will ask you

- The year of diagnosis
- Current medications and their doses
- Other health conditions
- Any procedures already done, such as deep brain stimulation (DBS)
- How far you are able to travel for study visits
- Whether a care partner can come to visits with you

### What to have ready

- A written list of current medications and doses
- Your neurologist's name and phone number
- The diagnosis date. The year is enough.
- A recent visit summary from the neurologist, if you have one

### What to ask them

- How many visits are there, and how long does each visit take?
  The listing already answers this: Assessments are scheduled at baseline, 6, 12, 18, and 24 months. Ask the coordinator to confirm it still applies.
- Is travel, parking, or my time reimbursed?
- Is there a placebo group, and what is my chance of being in it?
  The listing already answers this: This is an observational study, so there is no placebo and no experimental treatment is assigned. Researchers observe and collect information while you continue your usual care. Ask the coordinator to confirm it still applies.
- Would I need to stop or pause any of my current medications?
- What happens when the study ends? Could I stay on the treatment if it helps?

### What to expect

- Expect to wait a few days for a callback. A week is common. Calling or emailing again after that is fine and normal.
- Many callers do not end up joining. Screening out is common and is not a judgment about you or your health.
- Asking questions commits you to nothing. You can stop the process at any point.

---

*Canonical: https://parkinsonspathways.com/trial/NCT07567794*  
*HTML version: https://parkinsonspathways.com/trial/NCT07567794*  
*Source data: https://clinicaltrials.gov/study/NCT07567794*