Parkinson DiseaseNCT06487975
Bacillus Subtilis in Parkinson's Disease
A study testing Bacillus Subtilis in people with Parkinson Disease, run by University of Edinburgh at 2 sites in 2 countries.
Trial summary
The aim of this study is to evaluate whether the administration of Bacillus Subtilis influences gut and blood biomarkers relevant to the proposed mechanism(s) of action, as well as being acceptable as a regular supplement for people with Parkinson's disease. Read more about this study
- Who is it for?
- Ages 50 years and older
- Conditions the study is for
- Parkinson Disease
- What is being tested?
- Bacillus Subtilis
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 26 participants
- Where
- 2 sitesin 2 countries
- Study dates
- 2 May 2023to 20 Nov 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Who cannot join
- 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
Show all 11Show fewer
- 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
Trial locations and contacts
2 sites in 2 countries.
2 sites in 2 countries
Norway1 site
Norwegian Centre for Movement Disorders, Stavanger University Hospital
Stavanger
About this study
Official title: Effects of Bacillus Subtilis on Blood and Gut Biomarkers in Parkinson's Disease
The aim of this study is to evaluate whether the administration of Bacillus Subtilis influences gut and blood biomarkers relevant to the proposed mechanism(s) of action, as well as being acceptable as a regular supplement for people with Parkinson's disease.
Read the detailed description
Following informed consent, participants will undergo screening. If eligible, they will be invited to attend a baseline visit (week 0) to complete clinical assessments and provide a faecal and blood sample before starting their assigned intervention. Each participant will be randomised 1:1 to visually identical capsules containing either Bacillus Subtilis or placebo to be taken for 24 weeks. Telephone follow-up will be performed at week 8 to ensure compliance and answer any participant questions. Repeat clinical assessments and faecal/blood sample collection will take place at weeks 24 (treatment end date) and 36 (to assess longevity of biomarker changes after the intervention has stopped). Faecal samples will be collected at home within seven days prior to the clinic visits and brought to the appointment. Microbiota composition in faecal samples and blood biomarkers will be analysed in participant samples. Motor and non-motor symptom rating scales will also be administered.
- Conditions
- Parkinson Disease
- Being tested
- Bacillus Subtilis, Placebo
- Keywords
- probiotic, microbiome
- Medical subject headings
- Parkinson Disease
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Bacillus SubtilisDietary supplement
Bacillus Subtilis 1 capsule once daily in the morning (consisting of 10x10^9 Colony Forming Units)
PlaceboOther
1 visually identical placebo capsule once daily in the morning using the same carrier (microcrystalline cellulose) as the active (but not containing Bacillus Subtilis)
| Study group | Role | What they receive |
|---|---|---|
| Bacillus Subtilis | Experimental | Bacillus Subtilis 1 capsule once daily in the morning (consisting of 10x10^9 Colony Forming Units) Receives: Dietary Supplement: Bacillus Subtilis |
| Placebo | Placebo comparator | 1 visually identical placebo capsule once daily in the morning using the same carrier (microcrystalline cellulose) as the active (but not containing Bacillus Subtilis) Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
To assess the effect of Bacillus Subtilis on gut microbiome
Changes in presence and abundance of Bacillus Subtilis and other bacteria in faeces following probiotic administration versus placebo. Non-parametric tests (such as Wilcoxon signed-rank test and permutational multivariate analysis of variance) will be used for alpha and beta diversity analyses, and to identify genera that have significantly changed in abundance.
Measured: 24 weeks
To assess the effects of Bacillus Subtilis on blood biomarkers (sphingolipid profile)
Changes in sphingolipids following Bacillus Subtilis administration versus placebo measured using liquid chromatography-mass spectrometry
Measured: 24 weeks
To assess the effects of Bacillus Subtilis on blood biomarkers (pro-inflammatory cytokines)
Changes in pro-inflammatory cytokines following Bacillus Subtilis administration versus placebo measured using V-PLEX Proinflammatory Panel 1 Human Kit
Measured: 24 weeks
To assess the effects of Bacillus Subtilis on blood biomarkers (neurofilament light chain)
Changes in neurofilament light chain following Bacillus Subtilis administration versus placebo measured using Single Molecule Array assay
Measured: 24 weeks
To assess the effects of Bacillus Subtilis on blood biomarkers (alpha-synuclein species)
Changes in alpha synuclein species following Bacillus Subtilis administration versus placebo measured using α-syn real-time quaking-induced conversion assays
Measured: 24 weeks
To assess the effects of Bacillus Subtilis on blood biomarkers (lipid profile)
Changes in cholesterols/triglycerides following Bacillus Subtilis administration versus placebo
Measured: 24 weeks
To assess the effects of Bacillus Subtilis on blood biomarkers (fasting glucose)
Changes in fasting glucose following Bacillus Subtilis administration versus placebo
Measured: 24 weeks
To assess the effects of Bacillus Subtilis on blood biomarkers (haemoglobin A1C)
Changes in haemoglobin A1C following Bacillus Subtilis administration versus placebo
Measured: 24 weeks
To evaluate the acceptability of Bacillus Subtilis administration in PD patients
Descriptive analysis of custom-designed Acceptability Questionnaire which includes four questions on number of missed doses, ease of swallowing, daily dosing schedule, and any other barriers to tablet compliance.
Measured: 24 weeks
Secondary outcomes (1)
To evaluate the correlation between changes in gut and blood biomarkers following B. subtilis administration and motor/non-motor symptoms
Correlation between Primary Objectives 1 and 2 and motor/non-motor symptoms: Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS), Movement Disorder Society Non-Motor Rating Scale (MDS-NMS), Montreal Cognitive Assessment (MoCA) and Parkinson's Disease Questionnaire (PDQ-39)
Measured: 24 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Jul 2024
- Study start2 May 2023
- Primary completion5 Mar 2025
- Study completion20 Nov 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Parkinson DiseaseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 26 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Edinburgh
- Sponsor type
- University, hospital or other
- Collaborators
- Helse Stavanger HF, ADM Protexin
- Responsible party
- Sponsor
- Investigators
- David P Breen, MBChB, Study chair, NHS Lothian
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06487975
- Sponsor's protocol ID
- 22/WS/0100
- Status last verified
- Apr 2026
- First submitted
- 27 Mar 2024
- Last updated
- 8 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 8 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effects of Bacillus Subtilis on Blood and Gut Biomarkers in Parkinson's Disease
- ClinicalTrials.gov ID
- NCT06487975
- Acronym / sponsor ID
- 22/WS/0100
- Conditions
- Parkinson Disease
- Keywords
- probiotic, microbiome
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 26 participants (actual)
- Lead sponsor
- University of EdinburghUniversity, hospital or other
- Collaborators
- Helse Stavanger HF, ADM Protexin
- Study start
- 2 May 2023 (actual)
- Primary completion
- 5 Mar 2025 (actual)
- Study completion
- 20 Nov 2025 (actual)
- First posted
- 5 Jul 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The aim of this study is to evaluate whether the administration of Bacillus Subtilis influences gut and blood biomarkers relevant to the proposed mechanism(s) of action, as well as being acceptable as a regular supplement for people with Parkinson's disease.
Detailed description
Following informed consent, participants will undergo screening. If eligible, they will be invited to attend a baseline visit (week 0) to complete clinical assessments and provide a faecal and blood sample before starting their assigned intervention. Each participant will be randomised 1:1 to visually identical capsules containing either Bacillus Subtilis or placebo to be taken for 24 weeks. Telephone follow-up will be performed at week 8 to ensure compliance and answer any participant questions. Repeat clinical assessments and faecal/blood sample collection will take place at weeks 24 (treatment end date) and 36 (to assess longevity of biomarker changes after the intervention has stopped). Faecal samples will be collected at home within seven days prior to the clinic visits and brought to the appointment. Microbiota composition in faecal samples and blood biomarkers will be analysed in participant samples. Motor and non-motor symptom rating scales will also be administered.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Bacillus Subtilis | Experimental | Dietary Supplement: Bacillus SubtilisBacillus Subtilis 1 capsule once daily in the morning (consisting of 10x10^9 Colony Forming Units) |
| Placebo | Placebo comparator | Other: Placebo1 visually identical placebo capsule once daily in the morning using the same carrier (microcrystalline cellulose) as the active (but not containing Bacillus Subtilis) |
Who may qualify
- Ages
- 50 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- 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
Key exclusion criteria (11 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Bacillus SubtilisBacillus Subtilis 1 capsule once daily in the morning (consisting of 10x10^9 Colony Forming Units) | Dietary supplement | Bacillus Subtilis |
| Placebo1 visually identical placebo capsule once daily in the morning using the same carrier (microcrystalline cellulose) as the active (but not containing Bacillus Subtilis) | Other | Placebo |
Primary outcome
To assess the effect of Bacillus Subtilis on gut microbiome
Time frame: 24 weeks
Changes in presence and abundance of Bacillus Subtilis and other bacteria in faeces following probiotic administration versus placebo. Non-parametric tests (such as Wilcoxon signed-rank test and permutational multivariate analysis of variance) will be used for alpha and beta diversity analyses, and to identify genera that have significantly changed in abundance.
To assess the effects of Bacillus Subtilis on blood biomarkers (sphingolipid profile)
Time frame: 24 weeks
Changes in sphingolipids following Bacillus Subtilis administration versus placebo measured using liquid chromatography-mass spectrometry
To assess the effects of Bacillus Subtilis on blood biomarkers (pro-inflammatory cytokines)
Time frame: 24 weeks
Changes in pro-inflammatory cytokines following Bacillus Subtilis administration versus placebo measured using V-PLEX Proinflammatory Panel 1 Human Kit
To assess the effects of Bacillus Subtilis on blood biomarkers (neurofilament light chain)
Time frame: 24 weeks
Changes in neurofilament light chain following Bacillus Subtilis administration versus placebo measured using Single Molecule Array assay
To assess the effects of Bacillus Subtilis on blood biomarkers (alpha-synuclein species)
Time frame: 24 weeks
Changes in alpha synuclein species following Bacillus Subtilis administration versus placebo measured using α-syn real-time quaking-induced conversion assays
To assess the effects of Bacillus Subtilis on blood biomarkers (lipid profile)
Time frame: 24 weeks
Changes in cholesterols/triglycerides following Bacillus Subtilis administration versus placebo
To assess the effects of Bacillus Subtilis on blood biomarkers (fasting glucose)
Time frame: 24 weeks
Changes in fasting glucose following Bacillus Subtilis administration versus placebo
To assess the effects of Bacillus Subtilis on blood biomarkers (haemoglobin A1C)
Time frame: 24 weeks
Changes in haemoglobin A1C following Bacillus Subtilis administration versus placebo
To evaluate the acceptability of Bacillus Subtilis administration in PD patients
Time frame: 24 weeks
Descriptive analysis of custom-designed Acceptability Questionnaire which includes four questions on number of missed doses, ease of swallowing, daily dosing schedule, and any other barriers to tablet compliance.
1 secondary outcome
To evaluate the correlation between changes in gut and blood biomarkers following B. subtilis administration and motor/non-motor symptoms
Time frame: 24 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Apr 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
David P Breen, MBChB study chair
NHS Lothian
2 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Bacillus Subtilis in people with Parkinson Disease, run by University of Edinburgh at 2 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 8 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Norway, United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To assess the effect of Bacillus Subtilis on gut microbiome (time frame: 24 weeks). The study lists 9 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Apr 2026.