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CompletedNCT04249544Updated Oct 18, 2023

Social Decision Making in Parkinson's Disease

A Phase 1 interventional study of Pramipexole and Placebo in Parkinson Disease, sponsored by Vanderbilt University Medical Center. Completed at 1 site in United States. Open to participants aged 45 Years to 80 Years. Per ClinicalTrials.gov, last updated 2023-10-18.

Sponsored by Vanderbilt University Medical Center · Phase 1, Interventional, and Basic science

From the registry’s dates

  • Primary completion was Jun 2022, 4 years 4 months ago, and no results have been posted to the registry.
Phase
Phase 1
Study type
Interventional
Enrollment
18
Allocation
Non-randomized
Ages
45 Years to 80 Years
Sex
All
01

Study summary

Impulsive and compulsive behaviors occur in up to 46% of Parkinson's Disease (PD) patients taking dopamine agonist (DAA) medications. While these abnormal social behaviors have been studied in other neurodegenerative disorders, the true incidence of social problems, and the relationship to dopamine therapy, in PD patients remains unknown. This study is aiming to determine if dopamine agonists alter social decision-making and to determine if impaired social decision-making relates to dopamine-induced mesolimbic network dysfunction in PD patients. The protocol will include a screening visit, and on-DAA visit, and an off-DAA visit. For both the on and off DAA visits, participants will continue taking Carbidopa-Levodopa, but will withdrawal off of other PD related medications. Both visits will include an MRI, fMRI shock task, questionnaires to be filled out by other the participant and the caregiver, moral-decision making computer tasks, and the Unified Parkinsons Disease Rating Scale (UPDRS) part II and III. For the on-DAA visit, participants will take Pramipexole. For the off-DAA visit, participants will receive a placebo. Participants will remind blinded to which medication they are receiving that day and will be counterbalanced such that all participants will not take the Pramipexole or placebo on the same days.

Read the detailed description

Impulsive and compulsive behaviors occur in up to 46% of Parkinson's Disease (PD) patients taking dopamine agonist (DAA) medications. While these abnormal social behaviors have been studied in other neurodegenerative disorders, the true incidence of social problems, and the relationship to dopamine therapy, in PD patients remains unknown. This study is aiming to determine if dopamine agonists alter social decision-making and to determine if impaired social decision-making relates to dopamine-induced mesolimbic network dysfunction in PD patients. The protocol will include a screening visit, and on-DAA visit, and an off-DAA visit. For both the on and off DAA visits, participants will continue taking Carbidopa-Levodopa, but will withdrawal off of other PD related medications to reduce circulating drugs and residual drug effects. Both visits will include an MRI, fMRI shock task, questionnaires to be filled out by other the participant and the caregiver, moral-decision making computer tasks, and the Unified Parkinson's Disease Rating Scale (UPDRS) part II and III. For the on-DAA visit, participants will take Carbidopa-Levodopa 1 hour before the scan and will take 1mg of Pramipexole 1 hour before the scan. For the off-DAA visit, participants will take Carbidopa-Levodopa 1 hour before the scan and will take a placebo 1 hour before the scan. Participants will remind blinded to which medication they are receiving that day and will be counterbalanced such that all participants will not take the Pramipexole or placebo on the same days.

02

Conditions studied

  • Parkinson Disease

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Keywords

  • Impulsive behavior
  • Social decision making
  • Moral decision making
  • dopamine agonists
03

In context

Parkinson Disease

4,487 studies on the registry are indexed under Parkinson Disease; 1,082 are open to participants now.

This study's enrollment of 18 is below the median of 40 across 3,294 interventional studies indexed under Parkinson Disease.

Browse Parkinson Disease studies →

Lead sponsor

Vanderbilt University Medical Center is the lead sponsor of 824 studies on the registry; 164 are open to participants now.

Of its 122 completed or terminated interventional studies of FDA-regulated products, 91 (75%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
45 Years to 80 Years
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Age 45-80
  • Ability to give informed consent
  • Idiopathic Parkinson's disease
  • Currently taking dopamine agonist therapy
  • Mild symptom severity (Hoehn \& Yahr ≤ 3)
  • Disease duration of \<12 years
  • Demonstrated positive response to dopamine therapy

Exclusion criteria

Exclusion Criteria:

  • Medications classes that influence GABA concentrations: benzodiazepines, cholinesterase inhibitors, antipsychotics, opioids, and MAO inhibitors
  • History of substance abuse or use of any psychostimulants (other than caffeine) in the last 6 months or more than 4 times in lifetime
  • Current tobacco (or nicotine use) or alcohol intake greater than 8 ounces of whiskey or equivalent per week
  • Comorbid neurological disorders (e.g., stroke, peripheral neuropathy, seizure disorder) or history of head trauma (other than a single concussion)
  • Unstable medical condition, [e.g., diabetes or pulmonary disease, significant medical condition, including high blood pressure (systolic B.P. > 135, Diastolic B.P. > 85), or any hepatic, renal, cardiovascular, hematological, endocrine or ophthalmological condition]
  • History of major psychiatric illness (including any affective disorder, substance use disorder, psychotic disorder, or eating disorder)
  • Dementia
  • Deep brain stimulation
  • Contraindications to 3 Tesla MRI, e.g., extreme obesity, claustrophobia, cochlear implant, metal fragments in eyes, cardiac pacemaker, neural stimulator, tattoos with iron pigment and metallic body inclusions or other metal implanted in the body
  • Dyskinesia or tremor that would cause severe motion artifact during MRI scan
  • Clear indication of secondary gain
05

Study design

Phase
Phase 1
Primary purpose
Basic science
Allocation
Non-randomized
Intervention model
Crossover assignment
Masking
Double (Participant, Care provider)
Enrollment
18 participants (actual)

Study arms

  • Experimental
    Impulsive group, placebo then pramipexole

    half of the impulsive group will first get the placebo on the first day and pramipexole on the second day

    Drug: Pramipexole · Drug: Placebo

  • Experimental
    Impulsive group, pramipexole then placebo

    half of the impulsive group will first get the pramipexole on the first day and the placebo on the second day

    Drug: Pramipexole · Drug: Placebo

  • Experimental
    Non-impulsive group, placebo then pramipexole

    half of the non-impulsive group will first get the placebo on the first day and the pramipexole on the second day

    Drug: Pramipexole · Drug: Placebo

  • Experimental
    Non-impulsive, pramipexole then placebo

    half of the non-impulsive group will first get the pramipexole on the first day and the placebo on the second day

    Drug: Pramipexole · Drug: Placebo

Interventions

  • DrugPramipexole

    1mg of pramipexole

  • DrugPlacebo

    1mg equivalent of placebo

06

What researchers measure

Primary outcomes

  1. The change in a harm aversion cognitive moral decision-making task

    change in harm aversion from off drug visit to on drug visit

    Time frame: two weeks

  2. change in blood flow in the ventral striatum per ASL images

    change in CBF from off drug visit to on drug visit

    Time frame: two weeks

07

Study locations

1 site
  • Vanderbilt University Medical Center
    Nashville, Tennessee 37212, United States
08

References and documents

Study documents

  • Informed consent form · Apr 12, 2023

Documents are hosted by the registry — open the source record to download them.

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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Oct 18, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT04249544
Lead sponsor
Vanderbilt University Medical Center
Collaborators
United States Department of Defense
Responsible party
Richard Darby (Assistant Professor of Neurology, Vanderbilt University Medical Center) — Principal investigator
First posted
Jan 31, 2020
Start date
Dec 3, 2019
Primary completion
Jun 1, 2022
Completion
Sep 1, 2022
Last update
Oct 18, 2023

Study contacts

Richard R Darby, M.D.
principal investigator · Vanderbilt University Medical Center

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Oct 2023. You cannot join it, but the record below documents what was studied.

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