GBPDC: Gut-Brain in PD Consortium Master Protocol
Consortium for Gut-Brain Communication in Parkinson's Disease Master Protocol
Who can join
As published by the study on ClinicalTrials.gov. "Not stated" means the study hasn't said — ask the study team.
- Age
- 21 Years to 80 Years
- Sex
- All sexes
- Healthy volunteers
- Accepted
- Compensation
- Not stated
Other requirements are listed under Eligibility below. Only the study team can confirm whether you can join.
What to expect
No one can promise a trial will help you personally — that is what the research is trying to find out.
What participation involves
- Time periods mentioned: 24 months
Only what the study's summary and detailed description on ClinicalTrials.gov say. Time periods may describe the whole study or a part of it — ask the study team what applies to you.
Show the study's own words
- "Participation in the study will last up to 24 months (2 years)."
- Compensation
- Not stated
- Study-related exams and procedures are typically provided at no cost. This is how many trials work in general — confirm the details for this study with the study team.
- Participants are monitored closely by the research team throughout the study.
- Some participants may receive access to an investigational treatment, which is still being studied.
- Your participation helps researchers learn whether this approach could help future patients.
About this study
In plain language
This study looks at how the nerves linking the gut and brain may play a role in Parkinson’s disease (PD). It compares adults with PD, adults without PD, and adults at risk for PD. Taking part lasts up to 2 years and includes visits, questions, body samples, and gut tests.
The purpose of this research study is to identify the role that the gut-brain axis, the group of nerves that connect the brain and gut, plays in Parkinson's disease (PD). The National Institute of Diabetes and Digestive and Kidney Diseases is sponsoring this research study. During this study, specific groups of participants, also known as "cohorts", will be identified based on the severity of their PD. There will also be a cohort enrolling participants who do not have Parkinson's and a cohort enrolling participants that are at risk for developing PD. Each of these cohorts will be compared to the others to assess the differences in the gut-brain connection. Participants in this study will: * meet with a medical provider * answer questionnaires * give samples of blood, stool, and saliva * have X-rays taken while swallowing different foods (swallowing study) * have X-rays taken to see how long it takes markers to move through their colon (colon transit study) * 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) * have samples taken of their skin * have an anorectal manometry and a balloon expulsion test, where a small tube and balloon are placed in the rectum to measure muscle function. Participation in the study will last up to 24 months (2 years).
Compensation is read from the study's own description and may be missing — always confirm with the study team.
Eligibility
Who can join
- All groups: Be 21 to 80 years old.
- PD groups: Have a doctor’s diagnosis of PD that meets the study’s rules.
- PD groups: Be able to see, hear, think, and move well enough to take part.
- PD and control groups: Be willing and able to attend visits and complete tests. For PD groups, staff also review your ability and interest in staying involved for 3 years.
- Control group: Have no known disease that causes brain or nerve cells to break down, and live with someone who has PD.
- At-risk group: Meet study rules for early signs of PD. These include a sleep behavior disorder linked to acting out dreams, found by a sleep test or questionnaire, with a low sense of smell on a smell test.
Who can't join
- Other forms of parkinsonism, which cause PD-like symptoms; major thinking problems; or other brain, nerve, or medical conditions that could make the study unsafe or affect results.
- Low red blood cell or platelet levels, abnormal blood clotting, certain kidney or liver problems, or blood thinners that make the lower bowel exam too risky.
- Serious suicidal thoughts within 6 months, a suicide attempt within 2 years, or serious suicide risk; or alcohol or drug abuse or dependence within 2 years.
- Cancer now or within 5 years, except stable untreated prostate cancer or treated or removed skin carcinomas.
- Body mass index (BMI), a weight-to-height measure, over 35; weight under 50 kilograms (about 110 pounds); or being pregnant or breastfeeding.
- COVID-19 within 6 weeks before screening, or lasting COVID-19 symptoms that could affect safety or thinking tests. Recent use of an experimental study drug may also exclude you.
- Past stomach or bowel surgery, except appendix removal, hemorrhoid surgery, or gallbladder removal. Regular use of drugs that affect the gut lining, such as NSAID pain medicines more than 3 times a week.
- Crohn’s disease, ulcerative colitis, other forms of colon inflammation, or other long-term gut diseases that cause inflammation, such as celiac disease.
Simplified for readability. The official criteria below are what the study team uses.
Official eligibility 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.
Study sites (7)
CA
- Stanford University · Stanford, CA 94305Marian Shahid-Besanti, MSc · Study contact · 650-723-0060 · gutbrainresearch@stanford.eduKathleen L Poston, MD, MS · Principal investigatorLaren S Beckers, MD · Principal investigatorMore trials in Stanford
IL
- Rush University · Chicago, IL 60612Michelle Villanueva, MS · Study contact · 312-942-8927 · michelle_villanueva@rush.eduAli Keshavarzian, MD · Principal investigatorChristopher Goetz, MD · Principal investigatorMore trials in Chicago
- University of Chicago · Chicago, IL 60637Hanna Lancerio · Study contact · 773-633-8412 · hlancerio@bsd.uchicago.eduTao Xie, MD, PhD · Principal investigatorEugene Chang, MD · Principal investigatorMore trials in Chicago
MA
- Massachusetts General Hospital · Boston, MA 02114Anna Borodianski · Study contact · 617-724-0480 · GIMotilityResearch@MGH.HARVARD.EDUAleksander Videnovic, MD · Principal investigatorMore trials in Boston
MN
- Mayo Clinic · Rochester, MN 55905Kelly Feuerhak, BSN, RN, CCRP · Study contact · 507-255-6802 · rstgistudy@mayo.eduAdil Bharucha, MBBS, MD · Principal investigatorRodolfo Savica, MD, PhD · Principal investigatorMore trials in Rochester
NY
- Columbia University · New York, NY 10027Katharine Godfrey · Study contact · kb3217@cumc.columbia.eduBraden Kuo, MD · Principal investigatorMore trials in New York
SC
- Medical University of South Carolina · Charleston, SC 29425Stephanie N Slan, MBA, ACRP-CP · Study contact · slans@musc.eduMore trials in Charleston