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

University of California San Francisco (UCSF)

Status and phase: Suspended; Phase 2; Phase 1

Conditions: Parkinson Disease

Treatments: Drug: Rifaximin; Other: Placebo

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT03575195

17-22841

Details and patient eligibility

About

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.

Enrollment: 86 estimated patients

Sex: All

Ages: 30+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

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

Exclusion criteria

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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86 participants in 2 patient groups, including a placebo group

Intervention

Experimental group

Description:

Rifaximin

Treatment:

Drug: Rifaximin

Placebo

Placebo Comparator group

Description:

Matching placebo

Treatment:

Other: Placebo