Actively Recruiting

Phase 2
Age: 40Years - 80Years
All Genders
NCT05568498

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

Led by University of British Columbia · Updated on 2026-05-08

60

Participants Needed

1

Research Sites

153 weeks

Total Duration

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AI-Summary

What this Trial Is About

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.

CONDITIONS

Official Title

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

Who Can Participate

Age: 40Years - 80Years
All Genders

Eligibility Criteria

Eligible

You may qualify if you...

  • Confirmed diagnosis of Parkinson's disease based on UK Brain Bank criteria
  • Age between 40 and 80 years
  • Mild to moderate Parkinson's disease (Hoehn and Yahr stage 1-3 in the ON state)
  • Mild to moderate depression (BDI-II score 14-28 in the ON state)
  • Women of childbearing potential must use medically approved birth control and have a negative pregnancy test at screening and baseline
  • Willingness to maintain current physical activity levels during the study
  • Proficiency in English
Not Eligible

You will not qualify if you...

  • Diagnosis of atypical Parkinsonism
  • Active suicidality or active psychosis
  • Cognitive score (MoCA) less than 21 in the ON state
  • Severe depression (BDI-II score greater than 28 in the ON state)
  • Use of probiotics, Saccharomyces boulardii, or antibiotics in the past 3 months (yogurt and other probiotic foods allowed)
  • Use of natural health products affecting depression (e.g., St. John's Wort, passion flower, gaba, 5-htp, kava, bacopa, essential fatty acids)
  • Changes in psychotherapy or brain stimulation for mood or anxiety disorders in the last 4 weeks
  • Changes in antidepressant or anxiolytic medications in the last 4 weeks
  • Changes in Parkinson's medication in the last 2 weeks
  • Neurological diseases other than Parkinson's disease (e.g., Alzheimer's, dementia, Huntington's, brain tumor, seizures, multiple sclerosis)
  • Significant immune-compromised conditions or use of immune suppressants
  • Known bleeding disorder
  • Current illness or infections (e.g., cold, flu, hepatitis, HIV, gastroenteritis, fungal or parasitic infections)
  • Allergy to corn starch or corn
  • Concurrent Duodopa treatment for Parkinson's
  • Changes in Deep Brain Stimulation (DBS) settings in the last 4 weeks
  • New significant psychiatric symptoms after DBS likely related to the procedure
  • Women who are pregnant, breastfeeding, or planning pregnancy during the trial
  • Unstable or serious medical conditions (e.g., active cancer treatment, uncontrolled diabetes)
  • Drug or substance abuse
  • Inability to comply with study requirements or significant language/cognitive barriers

AI-Screening

AI-Powered Screening

Complete this quick 3-step screening to check your eligibility

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Trial Site Locations

Total: 1 location

1

Pacific Parkinson's Research Centre

Vancouver, British Columbia, Canada, V6T2B5

Actively Recruiting

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Research Team

M

Matthew Leung, BSc

CONTACT

A

Annie Kuan

CONTACT

How is the study designed?

Study Type

INTERVENTIONAL

Masking

QUADRUPLE

Allocation

RANDOMIZED

Model

PARALLEL

Primary Purpose

TREATMENT

Number of Arms

2

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