Using Bacillus Subtilis to improve symptoms in Parkinson's disease

Effects of Bacillus Subtilis on Blood and Gut Biomarkers in Parkinson's Disease

Not applicable Interventional University of Edinburgh · NCT06487975

This study is testing if a probiotic called Bacillus Subtilis can help improve symptoms for people with Parkinson's disease.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment52 (estimated)
Ages50 Years and up
SexAll
SponsorUniversity of Edinburgh Academic / other
Locations2 sites (Stavanger and 1 other locations)
Trial IDNCT06487975 on ClinicalTrials.gov

What this trial studies

This study evaluates the effects of Bacillus Subtilis, a probiotic, on gut and blood biomarkers in individuals with Parkinson's disease. Participants will be randomly assigned to receive either Bacillus Subtilis or a placebo for 24 weeks, with clinical assessments and sample collections occurring at baseline, week 24, and week 36. The study aims to determine the acceptability of Bacillus Subtilis as a supplement and its potential impact on motor and non-motor symptoms associated with Parkinson's disease.

Who should consider this trial

Good fit: Ideal candidates are individuals over 50 years old with a diagnosis of Parkinson's disease and stable dopaminergic medication for at least 3 months.

Not a fit: Patients who have used probiotic supplements or antibiotics in the past 3 months, or those with significant gastrointestinal issues, may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a novel probiotic treatment option that may improve symptoms and biomarkers in patients with Parkinson's disease.

How similar studies have performed: While the use of probiotics in neurological conditions is an emerging field, this specific approach with Bacillus Subtilis in Parkinson's disease is relatively novel and has not been extensively tested in prior studies.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Diagnosis of Parkinson's disease
* Able to provide written informed consent
* Over 50 years old
* Motor symptom duration over 12 months
* Stable dopaminergic medication regime for at least 3 months

Exclusion Criteria:

* Use of probiotic supplements and probiotic-fortified foods (such as probiotic drinks and yoghurts) within past 3 months
* Use of antibiotics within past 3 months
* Previous gastrointestinal surgery or chronic organic bowel disorder
* History of clinically significant motor fluctuations
* History of postural instability or falls
* Current smoker
* Known or suspected allergy to probiotics
* Regular use of antacids, proton pump inhibitors, laxatives or anti-diarrheal drugs
* Use of hypoglycaemic or diabetes drugs
* Participation in clinical trial of investigational medicinal product within past 3 months
* Co-morbidities or other factors that, in the opinion of the investigator, make the patient unlikely to comply with study protocol

Where this trial is running

Stavanger and 1 other locations

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 Parkinson Diseaseprobioticmicrobiome
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.