Radiation Therapy (RT) for Parkinson's Disease (PD)

Ultra-low Dose, DaT-SPECT-guided Radiation Therapy for the Treatment of Parkinson's Disease

The purpose of this study is to investigate the use of ultra-low, anti-inflammatory doses of radiation therapy (RT) for the treatment of Parkinson's Disease (PD). In this study, the TrueBeam LINAC utilizes a linear accelerator (LINAC) for the delivery of radiation therapy. Dynamic conformal arc (DCA) therapy will be used to deliver a total of five (5) once-a-day radiation treatments (RT) using DaT-SPECT (Dopamine Transporter-Single-Photon Emission Computed Tomography) and MRI imaging to guide radiation treatment planning.

Study Overview

• Status: Enrolling by invitation
• Conditions: Parkinson's Disease
• Intervention / Treatment: Radiation: Radiation therapy

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Minnesota
    • Rochester, Minnesota, United States, 55905
      • Mayo Clinic in Rochester

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria

• Age ≥ 45 and ≤ 70 years
• Diagnosis of Parkinson's disease by a Movement Disorder Neurologist
• Confirmation of unilateral Parkinson's disease by Dopamine Transporter (DaT) scan
• A score of 2 or less on the modified Hoehn and Yahr scale
• ECOG Performance Status (PS) ≤ 2 (Appendix I).
• No known genetic causes or predisposition to Parkinson's disease or related diseases.
• Ability to complete questionnaires, neurological exam, and follow-up imaging independently or with assistance
• Ability to provide written informed consent
• Willing to provide mandatory blood samples for correlative research purposes
• Willing to return to enrolling institution for follow-up

Exclusion Criteria

• Concomitant dementia diagnosis or concerns of other memory disorder
• Parkinson's Disease medication changes within the last 3 months
• Receipt of radiation therapy for Parkinson's Disease outside Mayo Clinic, Rochester

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Radiation Therapy; Patients with early-stage, non-genetic, unilateral Parkinson's Disease who will receive an ultra-low, anti-inflammatory dose of radiation therapy.	Radiation: Radiation therapy; Dynamic conformal arc (DCA) therapy will be used to deliver a total of five (5) 60cGy once-a-day radiation treatments (RT) using DaT-SPECT (Dopamine Transporter-Single-Photon Emission Computed Tomography) and MRI imaging to guide radiation treatment planning.; Other Names: LINAC TrueBeam Radiation Therapy System

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in progression of Parkinson's Disease	Slowing of progression will be defined as a 7-point decrease in the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III Motor Examination (physician-assessed motor symptoms) score. The score for this scale ranges from 0 to 132, with higher numbers indicating worse disease.	Baseline, 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the Movement Disorder Society - Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS Part III) score	The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III is a physician assessed motor examination that scores symptoms on a 0-4 scale, where 0 is normal and 4 is marked severity. The total Part III score is the sum of individual item scores. Higher scores indicate a greater severity of motor deficits.	Baseline, 3 months, 6 months
Change in Parkinson's Disease Questionnaire (PDQ-39) Score	The Parkinson's Disease Questionnaire (PDQ-39) is a 39-item questionnaire that assesses the impact of Parkinson's disease on quality of life. Each item is rated on a 5-point scale: 0: never, 1: occasionally, 2: sometimes, 3: often, and 4: always. The total score ranges from 0 (no impact) to 392 (severe impact).	Baseline, 3 months, 6 months

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Investigators: Principal Investigator: Yasamin Sharifzadeh-Moghaddam, Mayo Clinic

Study record dates

Study Major Dates

• Study Start (Actual): January 20, 2026
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): October 1, 2027

Study Registration Dates

• First Submitted: October 17, 2025
• First Submitted That Met QC Criteria: October 17, 2025
• First Posted (Actual): October 21, 2025

Study Record Updates

• Last Update Posted (Actual): June 16, 2026
• Last Update Submitted That Met QC Criteria: June 15, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: radiation; anti-inflammatory; neurodegenerative disease; low-dose
• Additional Relevant MeSH Terms: Synucleinopathies; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Movement Disorders; Parkinsonian Disorders; Basal Ganglia Diseases; Parkinson Disease; Neurodegenerative Diseases; Therapeutics; Radiotherapy
• Other Study ID Numbers: 24-006978

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No