Ultrasonic Debris Clearance to Promote Brain Resilience

May 1, 2026 updated by: Raag Airan, Stanford University

Safety and Feasibility Trial of Ultrasonic Debris Clearance to Promote Brain Resilience

This pilot study will evaluate the safety, tolerability, and feasibility of Ultrasonic Debris Clearance (UDC), a noninvasive low-intensity focused ultrasound intervention, in amyloid-positive adults who are asymptomatic but at risk for Alzheimer's disease, or who have mild cognitive impairment or mild dementia. The study is designed to test whether repeated UDC sessions can be delivered safely and feasibly in this population, while also exploring efficacy via biomarkers and clinical measures.

Study Overview

Study Type

Interventional

Enrollment (Estimated)

15

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • California
      • Stanford, California, United States, 94305
        • Stanford University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

1.1. Physician-reported amyloid positivity diagnosed by amyloid positron emission tomography (PET) OR historic CSF positivity of Abeta42, total tau, or phosphorylated tau OR positivity of plasma pTau-217.

1.2. Age ≥ 18 years. No gender/sex, racial, or ethnic preference. Subjects greater than 60 years of age will be assumed to be non-pregnant based on age and expected post-menopausal status. Female subjects under the age of 60 will complete a two-step assessment of pregnancy status (a self-reported assessment of menopause that proceeds to a urine human chorionic gonadotropin (hCG) test to confirm non-pregnancy, if the participant is not post-menopausal).

1.3. CDR Scale score less than or equal to 1.0, consistent with mild, very mild, or no dementia.

1.4. Ability and willingness to comply with the study procedures (six sessions sitting in a procedure chair for up to one hour for the procedure, with an ultrasound device placed on their scalp; additional time for the MRI assessment, blood draws, and cognitive assessments).

1.5. Ability to understand and the willingness to sign a written informed consent document.

Exclusion Criteria:

2.1. Dementia of moderate or higher severity (CDR > 1.0) 2.2. Intracranial tumors, acute or chronic hemorrhage (beyond petechiae/microhemmorhage), or other current or historic central nervous system specific pathology. Baseline MRI studies will be screened by the protocol director to ensure no exclusionary intracranial pathology is present.

2.3. Any other comorbidity that would prevent adequate interpretation of the study results per the treatment team (e.g. congenital brain malformations without clinical importance) 2.4. Ultrasound attenuators along the ultrasound beam path (metal, air, or bulky calcification) including thick hair or related adornments that cannot be undone for the study (e.g. turbans, dreadlocks, hairweaves/wigs) that would prevent adequate ultrasound gel coupling of the device to the scalp or could trap air in the ultrasound beam path.

2.5. Contraindications to MRI (unknown device, claustrophobia) or metallic hardware in the head that prevent adequate MRI visualization of the brain 2.6. Allergy or similar intolerance to the materials used for ultrasound device coupling (ultrasound gel, silicone) 2.7. Receipt of anti-amyloid monoclonal antibody therapy within 6 months prior to screening 2.8. Moderate or greater depressive symptoms at screening, defined as a Patient Health Questionnaire-9 (PHQ-9) total score >= 10.

2.9. Clinically significant suicidal ideation or behavior as assessed by the Columbia-Suicide Severity Rating Scale (C-SSRS) 2.10. Clinically significant hematologic abnormalities, defined as hematocrit < 35% for male or < 32% for female, absolute neutrophil cell count < 1500/uL, absolute lymphocyte count < 900/uL, or platelet count < 120,000/uL 2.11. Clinically significant hepatic, renal, respiratory, cardiovascular, or metabolic disease that increases risk or interferes with interpretation, defined as ALT/AST/ALP > 1.5 ULN, or eGFR < 50 mL/min/1.73m2, or recent MI/unstable angina/HF/cardiomyopathy within 6 months, 2.12. Significant bradycardia(<50/min) or tachycardia (>100/min) 2.13. Poorly controlled BP 2.14. Uncontrolled diabetes, defined as HbA1c > 7.5 2.15. Active clinically significant infection or other systemic illness affecting the CNS

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Other
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Active
Participants will receive the UDC ultrasound protocol applied to their head for multiple sessions across one month.
Ultrasonic debris clearance (UDC) delivered with a 250-kHz low-intensity transcranial ultrasound device for approximately 30 minutes per session across 8 sessions over 4 weeks. The intervention is designed to provide broad transcranial ultrasound exposure to promote glymphatic clearance, with real-time monitoring of transmitted power and matched study procedures including EEG, MRI, blood, and clinical assessments.
Sham Comparator: Sham
Participants will receive a sham version of the UDC ultrasound protocol applied to their head for multiple sessions across one month.
Sham procedure matched to the active UDC intervention in schedule, session duration, device setup, and study procedures, but without transcranial ultrasound energy delivery while maintaining participant blinding.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of Participants with Treatment-Related Adverse Events
Time Frame: baseline through 2 months post-treatment initiation (up to 3 months)
All reported adverse events including clinically meaningful vital sign changes, laboratory test abnormalities, physical and cognitive symptoms, and new imaging abnormalities not present at baseline.
baseline through 2 months post-treatment initiation (up to 3 months)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes from baseline in a tablet-based cognitive assessment
Time Frame: baseline through 1 month post-treatment initiation (up to 3 months)
Changes from baseline in tablet-based cognitive task performance (tabCAT) in the treatment condition compared to the sham
baseline through 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the CDR-SB
Time Frame: baseline, 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the Clinical Dementia Rating - Sum of Boxes (CDR-SB) in the treatment condition compared to the sham
baseline, 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the ADASCog13 measure of cognition.
Time Frame: baseline, 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the Alzheimer's Disease Assessment Scale - Cognitive Subscale (ADASCog13) in the treatment condition compared to the sham
baseline, 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the ADCS-MCI-ADL
Time Frame: baseline, 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the Alzheimer's Disease Cooperative Study - Activities of Daily Living for Mild Cognitive Impairment (ADCS-MCI-ADL) in the treatment condition compared to the sham
baseline, 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the Mini-Mental State Examination (MMSE)
Time Frame: baseline, 1 month post-treatment initiation (up to 3 months)
Changes from baseline in the Mini-Mental State Examination (MMSE) in the treatment condition compared to the sham
baseline, 1 month post-treatment initiation (up to 3 months)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Raag Airan, MD, PhD, Stanford University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

July 1, 2026

Primary Completion (Estimated)

July 1, 2027

Study Completion (Estimated)

July 1, 2027

Study Registration Dates

First Submitted

May 1, 2026

First Submitted That Met QC Criteria

May 1, 2026

First Posted (Actual)

May 7, 2026

Study Record Updates

Last Update Posted (Actual)

May 7, 2026

Last Update Submitted That Met QC Criteria

May 1, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • 85009

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

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on MCI With Increased Risk for Alzheimer Disease

Clinical Trials on Ultrasonic Debris Clearance

Subscribe