A Phase 1 interventional study of tributyrin in Parkinson Disease, sponsored by Nicolaas Bohnen, MD, PhD. Terminated at 1 site in United States. Open to participants aged 45 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-01-23.
Sponsored by Nicolaas Bohnen, MD, PhD · Phase 1, Interventional, and Treatment
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Among 1,649 studies in Parkinson Disease with a site in United States — 304 open to participants now, 387 under way, 7 of them phase 3. Parkinson Disease · United States.
Among the 1,649 studies in Parkinson Disease with a site in United States, this one is the 918th largest by enrollment of the 1,256 interventional ones that give a count, is one of 105 that started in 2022, is one of 175 in phase 1, and was the 1,272nd registered.
4,576 studies on the registry are indexed under Parkinson Disease; 1,087 are open to participants now.
Browse Parkinson Disease studies →304 of the 1,649 studies in Parkinson Disease with a site in United States are open now. Recruiting first, the newest first:
The Cleveland Clinic · Sites in United States
Ages 18+
University of Colorado, Denver · Sites in United States
Ages 45–75
University of Minnesota · Sites in United States
Ages 18+
Hoffmann-La Roche · Sites in United States, China, United Kingdom
Ages 40–85
Medical University of South Carolina · Sites in United States
Ages 50–85
A study can be open while its sites in United States have not opened yet or have stopped. Only those recruiting at a site in United States →
Of the 750 Parkinson Disease studies recruiting now, 312 (42%) set no upper age limit and 127 (17%) stop at 75 or younger; 64 take children under 18; 190 take healthy volunteers.
This study: 45 Years and older · all sexes · healthy volunteers too.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
1,649 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 226 · Phase 2 304 · Phase 3 145 · Phase 4 75
First in 1991; this study’s year is marked. 105 started in 2022.
By drug class, each counting the studies that test any of its medicines:
This study's enrollment of 18 is below the median of 40 across 3,355 interventional studies indexed under Parkinson Disease.
Median enrollment 36 across the 1,256 interventional studies, 78 across the 379 observational. Of the 1,139 that completed or were terminated, 435 (38%) have results posted.
This tab as a report to print or save as PDF → With an account.
470 of 1,649 have an industry lead sponsor. The 10 most frequent:
Nicolaas Bohnen, MD, PhD is the lead sponsor of 2 studies on the registry; none are open to participants now.
Nicolaas Bohnen, MD, PhD has 2 studies filed under Parkinson Disease — fewer than ten, so there is no comparison to draw.
137 of the studies in Parkinson Disease with a site in United States that are under way reach primary completion within a year, 1 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT06976268Phase 3Biohaven Therapeutics Ltd.A Study to Determine if BHV-8000 is Effective, Safe and Tolerable as a Treatment for Adults Living With Early Parkinson's Disease | 2027-08 |
| NCT06098612Massachusetts General HospitalPET Imaging Evaluation of [11C]SY08 | 2026-11 |
| NCT06489483University of Texas Southwestern Medical CenterAction Regulation Behavioral | 2026-11 |
| NCT05558189Stanford UniversityVibrotactile Coordinated Reset for the Treatment of Post Surgery Refractory Parkinson's Disease Patients | 2026-11-21 |
| NCT06773962TrueBinding, Inc.A Phase 2a Multicenter Clinical Trial of TB006 in Participants With Parkinson's Disease | 2026-11-28 |
Add all 137 to your calendar (.ics) → With an account.
Among the 1,649 studies in Parkinson Disease with a site in United States, from their registry updates:
This tab as a report to print or save as PDF → With an account.
Small exploratory open-label pilot study to assess the short-chain fatty acid (SCFA) prodrug tributyrin as a potential therapy for persons with Parkinson disease
The overarching goal of this small exploratory open-label pilot study is to explore metabolic (glucose metabolism, butyrate) and cognition (MoCa) before and after open-label treatment with the short-chain fatty acid (SCFA) prodrug tributyrin in a small pilot study in PD and normal control older adults. Positive findings in this small exploratory pilot trial may support target engagement study of SCFA supplementation in normal adults and PD.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will take 500mg TID tributyrin supplement for 30 days +/- 7 days.
Drug: tributyrin
Participants will take 500mg TID tributyrin supplement for 30 days +/- 7 days.
Drug: tributyrin
Post-biotic short chain fatty acid dietary supplement. Participants will take 500mg TID tributyrin supplement for 30 days +/- 7 days.
Whole Brain Butyrate PET Radiotracer Binding
Whole-brain butyrate distribution volume ratios (DVRs) were computed relative to a cerebral white matter reference region pre and post approximately 30 days of open-label treatment with tributyrin. Lower radiotracer binding is interpreted to reflect higher levels of (non-tracer) butyrate in the brain, whereas higher radiotracer binding reflects higher butyrate receptor binding site availability, indicating lower levels of non-tracer butyrate in the brain.
Time frame: Pre and Post approximately 30 days of intervention
Glucose Metabolism
Continuous glucose meter 7-10-day average glucose readings before/after open-label treatment with the SCFA prodrug tributyrin in patients with PD and normal controls. Healthy fasting blood glucose ranges from 70 to 99 milligrams per deciliter (mg/dL), with a healthy maximum of 180 mg/dL withing 2 hours of eating meals.
Time frame: Pre and Post approximately 30 days of intervention
| Milestone | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention |
|---|---|---|
| Started | 14 | 3 |
| Completed | 14 | 2 |
| Not completed | 0 | 1 |
| Withdrew: Physician decision | 0 | 1 |
Whole-brain butyrate distribution volume ratios (DVRs) were computed relative to a cerebral white matter reference region pre and post approximately 30 days of open-label treatment with tributyrin. Lower radiotracer binding is interpreted to reflect higher levels of (non-tracer) butyrate in the brain, whereas higher radiotracer binding reflects higher butyrate receptor binding site availability, indicating lower levels of non-tracer butyrate in the brain.
| Parametric DVR | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention |
|---|---|---|
| Pre-intervention | 1.81 ± 0.10 | 1.79 ± 0.02 |
| Post-intervention | 1.73 ± 0.10 | 1.74 ± 0.01 |
Continuous glucose meter 7-10-day average glucose readings before/after open-label treatment with the SCFA prodrug tributyrin in patients with PD and normal controls. Healthy fasting blood glucose ranges from 70 to 99 milligrams per deciliter (mg/dL), with a healthy maximum of 180 mg/dL withing 2 hours of eating meals.
| milligrams per deciliter (mg/dL) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention |
|---|---|---|
| Pre-Intervention | 135.00 ± 49.39 | 104.50 ± 3.54 |
| Post-Intervention | 139.33 ± 53.31 | 125.00 ± 4.24 |
Collected over For all subjects, data was collected during the 30 +/- 7 days of tributyrin intervention.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Parkinson's Disease Tributyrin Intervention | 0/14 (0%) | 0/14 (0%) | 13/14 (92.9%) |
| Healthy Control Tributyrin Intervention | 0/3 (0%) | 0/3 (0%) | 2/3 (66.7%) |
| Event | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention |
|---|---|---|
| GI DiscomfortGastrointestinal disorders | 7/14 | 0/3 |
| Behavioral DisturbancePsychiatric disorders | 0/14 | 1/3 |
| HeadacheNervous system disorders | 0/14 | 1/3 |
| Respiratory InfectionInfections and infestations | 4/14 | 0/3 |
| Sleep DisruptionNervous system disorders | 3/14 | 0/3 |
| Shakiness/DyskinesiaNervous system disorders | 2/14 | 0/3 |
| Urinary Tract InfectionInfections and infestations | 2/14 | 0/3 |
| Toe InjuryInjury, poisoning and procedural complications | 1/14 | 0/3 |
| ClaustrophobiaPsychiatric disorders | 1/14 | 0/3 |
| Gait DisturbancesNervous system disorders | 1/14 | 0/3 |
| Age, Categorical(Participants) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0 |
| Between 18 and 65 years | 5 | 1 | 6 |
| >=65 years | 9 | 2 | 11 |
| Age, Continuous(years) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| Mean | 66.4 ± 5.7 | 67.3 ± 10.6 | 66.5 ± 6.4 |
| Sex: Female, Male(Participants) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| Female | 5 | 2 | 7 |
| Male | 9 | 1 | 10 |
| Ethnicity (NIH/OMB)(Participants) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 0 |
| Not Hispanic or Latino | 14 | 3 | 17 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 |
| White | 14 | 3 | 17 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Region of Enrollment(participants) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| United States | 14 | 3 | 16 |
| Education(years) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| Mean | 17.9 ± 2.8 | 19.3 ± 3.5 | 18.1 ± 2.9 |
| Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III(units on a scale) | Parkinson's Disease Tributyrin Intervention | Healthy Control Tributyrin Intervention | Total |
|---|---|---|---|
| Mean | 46.9 ± 12.7 | 28.0 ± 20.5 | 43.6 ± 15.5 |
2 further baseline measures are reported on the registry.
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Jul 2022 to primary completion in Sep 2023, 14 months.
Results were first posted in Jan 2025, 1 year 3 months after primary completion.
How these figures are worked out, and which studies are left out of them.
This study is terminated, as verified in Dec 2024. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Tributyrin
Nicolaas Bohnen, MD, PhD