Changes in a gut bacterial gene (csgA) in people with Parkinson's disease

Evaluation of csgA Prevalence, Gene Expression and Week-to-Week Variability in Participants With Parkinson's Disease and a History of Gastrointestinal Dysfunction

Observational Vertero Therapeutics · NCT07175922

This project tests whether a gut bacterial gene called csgA is present or differs in people with Parkinson's disease who have gastrointestinal symptoms.

Quick facts

Study typeObservational
Enrollment200 (estimated)
Ages18 Years to 80 Years
SexAll
SponsorVertero Therapeutics Industry-sponsored
Locations1 site (Leiden)
Trial IDNCT07175922 on ClinicalTrials.gov

What this trial studies

This is an observational study enrolling people with Parkinson's disease to measure the presence and variability of the bacterial curli gene csgA in gut samples. Participants provide clinical history and stool samples that will be analyzed for csgA expression and related microbiome features using molecular methods. Eligible participants are adults aged 18–80 with a PD diagnosis within the past 10 years and current or past GI dysfunction, while people with major GI disorders or recent GI infections are excluded. The research is conducted at the Center for Human Drug Research in Leiden and does not involve any investigational treatments.

Who should consider this trial

Good fit: Ideal candidates are adults 18–80 years old with a Parkinson's diagnosis within 10 years who have current or past gastrointestinal dysfunction, can consent, and can complete study procedures in Dutch.

Not a fit: Patients without GI symptoms, with significant active gastrointestinal disease or recent GI surgery/infection, with PD diagnosed more than 10 years ago, or unable to participate in Dutch are unlikely to benefit from this observational project.

Why it matters

Potential benefit: If successful, the results could point to csgA as a target for future gut-directed therapies that might influence Parkinson's progression.

How similar studies have performed: Previous research has linked gut microbiome changes and bacterial amyloids to Parkinson's in experimental and epidemiologic work, but direct human data specifically on csgA expression remain limited and exploratory.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Between 18-80 years of age at ICF signing (inclusive)
* A diagnosis of PD within 10 years from the time of ICF signing
* Current or history of gastrointestinal (GI) dysfunction or constipation based on screening assessment
* All participants must understand and provide written informed consent prior to any study specific procedures
* Able to speak, read, and understand study procedures in Dutch sufficiently to allow completion of all study assessments

Exclusion Criteria:

* Any known GI disorder if deemed clinically significant by the investigator. GI disorders may include, but are not limited to: Crohn's disease, ulcerative colitis, celiac disease, irritable bowel syndrome, or lactose intolerance
* Recent GI infection in the past 3 months if deemed clinically significant by the investigator.
* Major GI surgery (excluding appendectomy/cholecystectomy), such as bariatric surgery, gastrectomy, esophagectomy, vagotomy, small intestine surgeries, any type of colectomy, colostomy and anorectal surgeries if deemed clinically significant by the investigator
* Any known current or past eating disorder if deemed clinically significant by the investigator
* Use of systemic antibiotics within 6 months prior to enrollment

Where this trial is running

Leiden

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Parkinsons Disease
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.