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Microbiota Intervention to Change the Response of Parkinson's Disease (MICRO-PD)

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ClinicalTrials.gov Identifier: NCT03575195
Recruitment Status : Recruiting
First Posted : July 2, 2018
Last Update Posted : October 27, 2022
Nova Southeastern University
Gateway Institute for Brain Research
Information provided by (Responsible Party):
University of California, San Francisco

Brief Summary:
The clinical phenotype of Parkinson's disease (PD) is quite variable, as is the response to and side effects from medications. While many patients respond to carbidopa/levodopa early on, motor fluctuations and dyskinesias can become a problem as the condition progresses, causing significant impairment in function and quality of life. The gut microbiome is of increasing interest in PD, potentially contributing to pathophysiology and clinical phenotype. Furthermore, gut bacteria are capable of metabolizing levodopa, which may decrease its ability to reach the central nervous system and could explain the variable effect seen clinically. Altering the population of drug-metabolizing bacteria could improve the clinical symptoms of PD and the benefit seen with medications. The investigators hypothesize that the gut microbiome in people with PD correlates with their phenotypic characteristics, which can be improved with targeting the microbiome through dietary or therapeutic interventions. The investigators propose a two-part clinical trial. First, a cross-sectional analysis will correlate the microbiome profile with (a) the clinical phenotype of PD and (b) medication response. Second, a randomized, controlled trial, will evaluate the effect of microbiome manipulation on clinical phenotype and medication response. The investigators plan to reduce the level of bacteria through antibiotic use, resetting the potentially disadvantageous microbiome population. Outcomes will include changes in clinical symptoms, alterations in the the microbiome, and changes in serum markers of inflammation. This thorough characterization will broaden our understanding of the gut-brain axis significantly in PD in clinically relevant ways that have yet to be explored.

Condition or disease Intervention/treatment Phase
Parkinson Disease Drug: Rifaximin Other: Placebo Phase 1 Phase 2

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 86 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Microbiota Intervention to Change the Response of Parkinson's Disease
Actual Study Start Date : July 15, 2019
Estimated Primary Completion Date : December 2022
Estimated Study Completion Date : June 2023

Resource links provided by the National Library of Medicine

Drug Information available for: Rifaximin

Arm Intervention/treatment
Experimental: Intervention
Drug: Rifaximin
Rifaximin 550mg orally

Placebo Comparator: Placebo
Matching placebo
Other: Placebo
Placebo control

Primary Outcome Measures :
  1. MDS-UPDRS Part III [ Time Frame: Two weeks ]
    The Movement Disorders Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is a validated scale that quantifies many of the symptoms and signs of Parkinson's disease. Part III in particular focuses on the motor symptoms of Parkinson's disease through a neurologic exam. The exam is often performed when medications are held for 8-12 hours (the "OFF" state) and again when medications are given and providing therapeutic benefit (the "ON" state), and the difference between scores is calculated. The scale goes from a minimum of 0 to a maximum of 132. There is no specific cutoff, but a higher score indicates a higher severity of symptoms. The trial will examine the change in the MDS-UPDRS Part III both OFF and ON medication after the intervention.

  2. Percent of OFF time according to home motor diaries [ Time Frame: Two weeks ]
    Patients with Parkinson's disease often have times where levodopa is providing therapeutic benefit and times when it is not. "OFF" time indicates the times of day where levodopa therapy is not providing therapeutic benefit. An outcome of the trial will be the change in medication OFF time that the participant experiences at home, according to motor diaries.

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Ages Eligible for Study:   30 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Parkinson's disease
  • Stable on levodopa therapy with fluctuations

Exclusion Criteria:

  • Chronic gastrointestinal disease
  • Recent antibiotic or probiotic therapy
  • Pregnant
  • Immunocompromised

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03575195

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Contact: Hannah McCarthy Potter, BA 415-514-6257 Hannah.mccarthypotter@ucsf.edu
Contact: Ethan Brown, MD 415-514-6257 ethan.brown@ucsf.edu

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United States, California
University of California San Francisco Recruiting
San Francisco, California, United States, 94115
Contact: Hannah McCarthy Potter, BA    415-514-6257    Hannah.MccarthyPotter@ucsf.edu   
Sponsors and Collaborators
University of California, San Francisco
Nova Southeastern University
Gateway Institute for Brain Research
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Principal Investigator: Caroline Tanner, MD, PhD University of California, San Francisco
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Responsible Party: University of California, San Francisco
ClinicalTrials.gov Identifier: NCT03575195    
Other Study ID Numbers: 17-22841
First Posted: July 2, 2018    Key Record Dates
Last Update Posted: October 27, 2022
Last Verified: October 2022
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: Yes
Additional relevant MeSH terms:
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Parkinson Disease
Parkinsonian Disorders
Basal Ganglia Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Movement Disorders
Neurodegenerative Diseases
Anti-Bacterial Agents
Anti-Infective Agents
Gastrointestinal Agents