Clinical trial NCT06762028: Exploring the Relationship Between L-dopa Responsiveness and Small Intestinal Microbiome in Parkinson's Disease
Official title: Exploring the Relationship Between L-dopa Responsiveness and Small Intestinal Microbiome in Parkinson's Disease
Study type: OBSERVATIONAL
Overall status: NOT_YET_RECRUITING
Conditions: Parkinson Disease
Keywords: SIMBA
small intestine
L-dopa
Lead sponsor: University of Calgary
Sponsor class: OTHER
First posted: 2025-01-07
Enrollment: 100
Sex: ALL
Minimum age (years): 50
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: CROSS_SECTIONAL
Sampling method: PROBABILITY_SAMPLE
Study population: Any patient with Parkinson disease fulfilling section criteria.

Brief summary: The investigators hypothesize that small intestinal (SI) microbiome biomarkers predict the responsiveness to oral levodopa/carbidopa in people with Parkinson's disease (PwPD). The investigators will analyze the bacterial species and function of bacterial pathways influencing the responsiveness of PwPD to oral L-dopa. The investigators will pursue this goal using a reliable capsule system (SIMBA capsule, Nimble Science, Calgary, AB) that suitably captures SI luminal fluid for multi-omics analysis.


Eligibility criteria: Inclusion Criteria:

1. Males and females aged 50-85 years old at time of on-site visit. (ages 81-85 will be assessed on a per case basis by the principal investigator)
2. Signed Informed consent.
3. Willing \& able to comply with study procedures (including SIMBA capsule ingestion) and have study assessments performed.
4. Able to swallow a size-00 capsule (25mm length) in OFF state.
5. Diagnosis of idiopathic PD (Clinically Probable PD), including documented levodopa responsiveness.
6. Treatment with an immediate release levodopa formulation during the day at a stable dose for at least 2 months prior to enrollment.

Exclusion Criteria:

1. Any risk of capsule non-excretion related to intercurrent gastrointestinal conditions.
2. Use of any medications in the week prior to the on-site study visit, unless part of regular treatment, that could substantially alter gastrointestinal motor function.
3. History of oropharyngeal dysphagia, or other swallowing disorder with a risk of capsule aspiration, e.g., SDQ score \> 4.
4. Any concomitant or previous treatment (\<2 months from on-site study visit) with significant anti-inflammatory or immune suppressant medication, e.g., DMARDs, biologicals or systemic corticosteroids, except non-chronic PRN use of an NSAID and/or 5-ASA (mesalazine) treatment.
5. Active cancer within 5 years.
6. Clinically significant immune deficiency (according to Investigator's judgement).
7. Antibiotic use (except for local use), ≤12 weeks prior to on-site study visit, or Fecal Microbiota Transplantation anytime in medical history.
8. Use of prebiotics, or probiotics ≤2 weeks prior to the on-site study visit.
9. Dementia in medical history.
10. Insulin-dependent diabetes mellitus.
11. Current Psychosis episode by clinical judgement based on anamnesis.
12. Pregnancy.
13. Alcohol or drug abuse.
14. Deep brain stimulation or Duodopa/Lecigon treatment.

Primary outcomes:
measure: Change of Part 3 score of the MDS-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) on L-dopa challenge test
timeFrame: Same day of study visit
Secondary outcomes:
measure: time latency to full "ON" state
timeFrame: Same day of study visit
measure: Part 4 score of the MDS-UPDRS
timeFrame: Same day of study visit
measure: Maximum observed plasma concentration of L-dopa (Cmax)
timeFrame: Same day of study visit
measure: Time to maximum observed plasma concentration (Tmax)
timeFrame: Same day of study visit
measure: Area under the L-dopa concentration-time curve (0-3 hours; AUC0-3 h)
timeFrame: Same day as study visit
Other outcomes:
Locations:
Study officials:
References: