← Back to Clinical Trials
Recruiting Phase 1 NCT04246437

NCT04246437 [18F]F-DOPA Imaging in Patients With Autonomic Failure

◆ AI Clinical Summary
Plain-language summary for patients
Clinical Trial Summary
NCT ID NCT04246437
Status Recruiting
Phase Phase 1
Sponsor Daniel Claassen
Condition Autonomic Failure
Study Type INTERVENTIONAL
Enrollment 40 participants
Start Date 2020-02-04
Primary Completion 2027-02-01

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
[18F]FDOPACarbidopa 200mg oral doseEntacapone 400mg oral dose

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 1 is the earliest stage of human testing — safety and dosage are the primary focus. Visits are frequent and medical supervision is intensive. You will be among the first people to receive this treatment.

This trial targets 40 participants in total. It began in 2020-02-04 with a primary completion date of 2027-02-01.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Alpha-synucleinopathies refer to age-related neurodegenerative and dementing disorders, characterized by the accumulation of alpha-synuclein in neurons and/or glia. The anatomical location of alpha-synuclein inclusions (Lewy Bodies) and the pattern of progressive neuronal death (e.g. caudal to rostral brainstem) give rise to distinct neurological phenotypes, including Parkinson's disease (PD), Multiple System Atrophy (MSA), Dementia with Lewy Bodies (DLB). Common to these disorders are the involvement of the central and peripheral autonomic nervous system, where Pure Autonomic Failure (PAF) is thought (a) to be restricted to the peripheral autonomic system, and (b) a clinical risk factor for the development of a central synucleinopathy, and (c) an ideal model to assess biomarkers that predict phenoconversion to PD, MSA, or DLB. Such biomarkers would aid in clinical trial inclusion criteria to ensure assessments of disease- modifying strategies to, delay, or halt, the neurodegenerative process. One of these biomarkers may be related to the neurotransmitter dopamine (DA) and related changes in the substantia nigra (SN) and brainstem. \[18F\]F-DOPA is a radiolabeled substrate for aromatic amino acid decarboxylase (AAADC), an enzyme involved in the production of dopamine. Use of this radiolabeled substrate in positron emission tomography (PET) may provide insight to changes in monoamine production and how they relate to specific phenoconversions in PAF patients. Overall, this study aims to identify changes in dopamine production in key regions including the SN, locus coeruleus, and brainstem to distinguish between patients with PD, MSA, and DLB, which may provide vital information to predict conversion from peripheral to central nervous system disease.

Eligibility Criteria

Inclusion Criteria: 1. Patients with a diagnosis if pure autonomic failure 2. Patients with autonomic failure and possible PD, MSA, or DLB 3. Healthy adults aged 18 and above 4. Clinical exam confirming clinical designation Exclusion Criteria: * Subjects who have any type of bioimplant activated by mechanical, electronic, or magnetic means (e.g., cochlear implants, pacemakers, neurostimulators, biostimulators, electronic infusion pumps, etc.), because such devices may be displaced or malfunction. * Subjects who have any type of ferromagnetic bioimplant that could potentially be displaced. * Subjects who have cerebral aneurysm clips. * Subjects who may have shrapnel imbedded in their bodies (such as from war wounds), metal workers and machinists (potential for metallic fragments in or near the eyes). * Subjects who are pregnant, because the effects of high field MRI on fetuses are not yet known. * Minors (younger than 18 years) Also excluded are subjects incapable of giving informed written consent: * Subjects who cannot adhere to the experimental protocols for any reason, or have an inability to communicate with the researcher. * Subjects who have limited mental ability to give informed consent, mentally retarded, altered mental status, mental disability, confusion, or psychiatric disorders. * Prisoners

Contact & Investigator

Central Contact

Daniel O Claassen, MD, MS

✉ daniel.claassen@vumc.org

📞 615-936-1007

Frequently Asked Questions

Who can join the NCT04246437 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Autonomic Failure. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT04246437 trial and what does that mean for participants?

Phase 1 trials are the first stage of human testing. The primary goal is to assess safety and determine appropriate dosage levels. Participants are closely monitored. These trials typically involve a small number of volunteers.

Is NCT04246437 currently recruiting?

Yes, NCT04246437 is actively recruiting participants. Contact the research team at daniel.claassen@vumc.org for enrollment information.

Where is the NCT04246437 trial being conducted?

This trial is being conducted at Nashville, United States.

Who is sponsoring the NCT04246437 clinical trial?

NCT04246437 is sponsored by Daniel Claassen. The trial plans to enroll 40 participants.

Related Trials

ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: September 2026  ·  Data Methodology