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Enrolling by Invitation

NCT Number: NCT05826457

North American Prodromal Synucleinopathy Consortium Stage 2

This study will enroll participants with idiopathic REM sleep behavior disorder (RBD) and healthy controls for the purpose of preparing for a clinical trial of neuroprotective treatments against synucleinopathies.

Enrolling by Invitation

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Key information

About this study

REM sleep behavior disorder (RBD) is a disorder where people act out their dreams. People with RBD often, but not always, develop Parkinson's Disease, dementia with Lewy bodies, multiple system atrophy, or other neurodegenerative diseases of the synucleinopathy type.

The North American Prodromal Synucleinopathy Consortium Stage 2 (NAPS2) was formed with the purpose of enrolling participants with RBD, in anticipation of a future clinical trial of a neuroprotective trreatment against synucleinopathies. The NAPS Consortium will collect standardized clinical assessments, biofluids, and neuroimaging data. The RBD group will also undergo two overnight sleep studies. Some of this data will be used to develop biomarkers for synucleinopathies in the prodromal (presymptomatic) stage as well as a trial-ready registry of participants.

RBD group procedures include a clinical assessment, questionnaires, blood draw, neuroimaging (MRI and DaTscan), polysomnogram (sleep study), and optional lumbar puncture.

Control group procedures include a clinical assessment, questionnaires, blood draw, neuroimaging (MRI), and lumbar puncture.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

for RBD Group

  • Polysomnogram-confirmed RBD by ICSD-3 criteria
  • Capable of providing informed consent at time of study enrollment
  • Age > 18 years

Exclusion criteria

for RBD Group

  • Diagnosis of PD, dementia of any type, or MSA unless previous participant in NAPS1.
  • Narcolepsy-associated RBD
  • RBD secondary to any known cause except prodromal synucleinopathy.
  • Participation in a clinical trial, except by specific permission by the Executive Committee
  • In the opinion of the investigator, the individual has a clinically significant uncontrolled medical condition that would impede safe completion of the study protocol

Inclusion criteria

for Control Group

  • Ability to provide written consent
  • Age > 18 years
  • Must meet age, sex, and race matching criteria per the Data Management and Statistical core recommendations for the site
  • Must be willing to undergo all testing procedures, including neuroimaging and lumbar puncture.
  • Normal capacity to perform complex activities of daily living independently based on informant or physician report

Exclusion criteria

for Control Group

  • History of dream enactment behavior to suggest RBD
  • Parkinsonism, MSA, dementia, or mild cognitive impairment
  • Active central nervous system, systemic, psychiatric condition or use of psychoactive medication that would adversely affect cognitive, neuropsychiatric, motor, or autonomic functioning.
  • Contraindications to complete MRI.
  • Contraindications to lumbar puncture.
  • Participation in a clinical trial, except by specific permission by the Executive Committee
  • In the opinion of the investigator, the individual has a clinically significant uncontrolled medical condition that would impede safe completion of the study protocol

Treatment and study plan

Primary outcomes

  1. Prodromal Synucleinopathy Rating Scale

    Time frame: up to 5 years

    Rating scale combining neurocognitive battery, motor, autonomic, olfaction, color vision functions. Global score range 0-3, with higher score indicating greater symptoms of synucleinopathy.

Sponsors and collaborators

Lead sponsor

Washington University School of Medicine

Other

Collaborators

  • Emory University
  • Massachusetts General Hospital
  • Mayo Clinic
  • McGill University
  • National Institute of Neurological Disorders and Stroke (NINDS)
  • National Institute on Aging (NIA)
  • National Institutes of Health (NIH)
  • Oregon Health and Science University
  • Stanford University
  • University of California, Los Angeles
  • University of Minnesota

Registry information

Acronym: NAPS2

Important dates

Study start
2022
Primary completion
2027
Study completion
2028
First posted
Apr 24, 2023
Registry last updated
May 13, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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