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Recruiting Phase 2 NCT05568498

NCT05568498 Probiotic Treatment for Depression and Associated Mood Disorders in Parkinson's Disease

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Clinical Trial Summary
NCT ID NCT05568498
Status Recruiting
Phase Phase 2
Sponsor University of British Columbia
Condition Parkinson Disease
Study Type INTERVENTIONAL
Enrollment 60 participants
Start Date 2025-01-20
Primary Completion 2027-12-31

Eligibility & Interventions

Sex All sexes
Min Age 40 Years
Max Age 80 Years
Study Type INTERVENTIONAL
Interventions
ProbioticPlacebo

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

In Phase 2, researchers evaluate early signs of effectiveness. You may be randomized to receive the active treatment or a comparator. Monitoring continues closely.

This trial targets 60 participants in total. It began in 2025-01-20 with a primary completion date of 2027-12-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

This study evaluates the use of an oral multi-strain probiotic in the treatment of depression in individuals with Parkinson's Disease. Participants will be randomized to either a 12-week multi-strain probiotic treatment or placebo intervention.

Eligibility Criteria

Inclusion Criteria: 1. Confirmed diagnosis of Parkinson's disease based on UK Brain Bank criteria 2. Between the ages of 40-80 years 3. Mild to Moderate PD (Hoehn and Yahr stage between 1-3 in the "ON" state) 4. Mild to moderate depression (BDI-II score of 14-28 in the "ON" state) 5. Women of childbearing potential must agree to use a medically approved method of birth control (e.g., hormonal contraceptives, intrauterine devices, vasectomy/tubal litigation, barrier methods and double barrier method) and must have negative pregnancy test results at screening and baseline 6. Willingness to maintain current physical activity levels during study period 7. English proficiency Exclusion Criteria: 1. Atypical Parkinsonism 2. Active suicidality 3. Active psychosis 4. Cognitive score (MoCA) of \< 21 in the "ON" state 5. Severe depression (BDI-II score \> 28 in the "ON" state) 6. Probiotic, Saccharomyces boulardii and/or antibiotic use in the past 3 months (yogurt, kefir, and other probiotic-containing foods are allowed) 7. The use of natural health products that affect depression (e.g., St. John's Wort, passion flower, gaba, 5-htp, kava, bacopa, efa's) 8. Change in the schedule of concurrent psychotherapy or brain stimulation for the treatment of mood or anxiety disorders in the last 4 weeks 9. Change in antidepressant or anxiolytic medication (including benzodiazepines) within the last 4 weeks 10. Change in Parkinson's medication within the last 2 weeks 11. Neurological disease other than PD, including Alzheimer's disease, multi-infarct dementia, Huntington's disease, normal pressure hydrocephalus, a brain tumour, progressive supranuclear palsy, seizure disorder, subdural hematoma, multiple sclerosis, or history of significant head trauma 12. A significant immune-compromised condition due to either a health condition or use of an immune suppressant (e.g., AIDS, lymphoma, chemotherapy treatment, patients undergoing long-term systemic corticosteroid or immunosuppressant treatment) 13. A known bleeding disorder 14. Current illness (e.g., a cold or flu-like symptoms) and infections (e.g., hepatitis, HIV, gastroenteritis, fungal, or parasitic infections) 15. Allergy to corn starch or corn 16. Concurrent treatment for Parkinson's disease with Duodopa 17. Change in Deep Brain Stimulation (DBS) stimulation parameters in the last 4 weeks 18. New onset of significant psychiatric symptoms following DBS procedure that are considered likely related 19. Women who are pregnant, breastfeeding, or planning to become pregnant during the course of the trial 20. Unstable medical conditions or serious disease/conditions (e.g., cancer undergoing active treatment, poorly controlled diabetes) 21. Drug and/or substance abuse 22. The patient, in the opinion of the Investigator, is unable to adhere to the requirements of the study. This includes any patient who, in the judgment of the Investigator, is likely to be noncompliant during the study, or unable to cooperate because of a significant language barrier or cognitive impairment

Contact & Investigator

Central Contact

Matthew Leung, BSc

✉ Matthew.Leung@ubc.ca

📞 604-827-1905

Frequently Asked Questions

Who can join the NCT05568498 clinical trial?

This trial is open to participants of all sexes, aged 40 Years or older, up to 80 Years, studying Parkinson Disease. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT05568498 trial and what does that mean for participants?

Phase 2 trials evaluate whether the treatment shows signs of effectiveness while continuing to monitor safety. More participants are enrolled than in Phase 1 to help refine the treatment protocol.

Is NCT05568498 currently recruiting?

Yes, NCT05568498 is actively recruiting participants. Contact the research team at Matthew.Leung@ubc.ca for enrollment information.

Where is the NCT05568498 trial being conducted?

This trial is being conducted at Vancouver, Canada.

Who is sponsoring the NCT05568498 clinical trial?

NCT05568498 is sponsored by University of British Columbia. The trial plans to enroll 60 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: July 2026  ·  Data Methodology