Ultrasound Neuroimmune Modulation in Adults With Rheumatoid Arthritis (SUSTAIN)

January 22, 2026 updated by: Surf Therapeutics

Ultrasound Neuroimmune Modulation in Adults With Rheumatoid Arthritis: Feasibility and Safety in a Multicenter, Randomized, Double-Blind, Sham-Controlled Trial

This two-stage, multicenter clinical trial is designed to evaluate the feasibility, safety, and preliminary efficacy of at-home ultrasound stimulation to activate immune-neuromodulation in patients with rheumatoid arthritis (RA) and at least moderate disease activity. The study will enroll up to 40 participants at up to 6 sites across 2 stages. The findings from this trial will directly inform the design and power calculations for a future pivotal trial by identifying an appropriate effect size and confirming protocol feasibility and safety for a daily home-use therapy.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Stage 1 is an open-label pilot study of 5-8 participants receiving active daily ultrasound stimulation for 8 weeks. The primary objective is to assess feasibility and safety, defined by the absence of device-related serious adverse events (SAEs) or Grade ≥2 adverse events (AEs) requiring medical intervention per CTCAE criteria. Data from Stage 1 will be used to refine trial procedures and confirm readiness for Stage 2.

Stage 2 consists of a randomized double-blind, sham-controlled study enrolling up to 30 participants, allocated 2:1 to receive active or sham daily ultrasound stimulation for 8 weeks. This stage is designed to estimate the treatment effect size, using clinical and biomarker-based endpoints, and to collect safety and adherence data on a larger cohort.

All participants will be followed through Week 12 to assess post-treatment safety and durability of clinical and immunologic effects.

Study Type

Interventional

Enrollment (Estimated)

40

Phase

  • Phase 2

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

  • United States
    • Texas
      • Colleyville, Texas, United States, 75034
        • Recruiting
        • Precision Comprehensive Clinical Research Solutions
        • Principal Investigator:
          • Dhiman Basu, MD
        • Contact:
      • Irving, Texas, United States, 75061
        • Recruiting
        • Precision Comprehensive Clinical Research Solutions
        • Principal Investigator:
          • Renuka Basavaraju, MD
        • Contact:

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:

  • At least 18 years old
  • Diagnosis of rheumatoid arthritis as defined by ACR/EULAR 2010 classification criteria
  • A positive test result for Rheumatoid Factor (RF) > 14 IU/mL and/or Anti-Citrullinated Protein Antibodies (Anti-CCP) ≥ 20 U/mL
  • At least moderate disease activity, defined as DAS28-CRP > 3.8 and at least 4/28 tender and 4/28 swollen joints at the screening and baseline visits
  • High sensitivity CRP (hsCRP) ≥ 10 mg/L at the screening and baseline visits
  • On stable dose of background DMARD therapy (see exclusion criteria)
  • Able and willing to comply with all study-related procedures, including at-home device use, daily treatment, scheduled visits, and assessments

Exclusion Criteria:

  • Unable to provide informed consent
  • Current or planned participation in another interventional clinical trial
  • Prior use of > 2 biologic or targeted synthetic DMARDs for RA where the primary reason for discontinuation was efficacy

  • Conventional synthetic DMARDs:

    • Initiated within last 12 weeks or adjusted dose within 4 weeks prior to enrollment
    • Inability to maintain a stable dose during the study

  • Biologic DMARDs:

    • Initiated or dose-adjusted within 12 weeks prior to enrollment
    • Inability to maintain a stable dose during the study

  • JAK inhibitors:

    • Use within 4 weeks prior to enrollment or expected use during study participation

  • Corticosteroids:

    • Initiated or dose-adjusted within 4 weeks prior to enrollment
    • Current dose > 10 mg/day prednisone (or equivalent)
  • Current tobacco or nicotine product use
  • Pregnant or planning to become pregnant during the study period
  • Known hypersensitivity to ultrasound gel or membrane components
  • Active bacterial, viral, or fungal infection
  • Receiving chemotherapy or immunotherapy for malignancy
  • History of splenic disorders, including splenectomy, congenital asplenia, or splenomegaly on screening ultrasound
  • Rash, wound, or skin infection overlying the spleen
  • History of vagal nerve injury, vagotomy, or known autonomic neuropathy
  • Recent abdominal surgery or trauma within 30 days of screening
  • Uncontrolled fibromyalgia or other diffuse pain syndromes that may confound symptom reporting

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: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Treatment
Daily active stimulation for 8 weeks
Device: Active treatment
Daily active ultrasound stimulation
Sham Comparator: Control
Daily sham stimulation, for 8 weeks, which will look and feel the same as active stimulation, but with no ultrasound energy entering the body
Device: Sham (No Treatment)
Daily sham ultrasound stimulation

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in high sensitivity CRP (hsCRP)
Time Frame: 8 weeks
The primary endpoint is the change in hsCRP from baseline to weeks 2, 4, 6 and 8. The baseline value will be calculated as the average of the screening and baseline visits, both of which must be ≥ 10 mg/L.
8 weeks
Incidence of Adverse Events
Time Frame: 12 weeks
All adverse events (AEs) regardless of treatment group that occur over the 12 week enrollment period will be coded and summarized by frequency, severity, and relatedness using the latest MedDRA version (v28.1).
12 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
American College of Rheumatology (ACR) 20, 50 and 70 response rates
Time Frame: Week 8
Difference between treatment and control groups in the proportion of subjects who achieve at least 20%, 50%, and 70% improvement from baseline to Week 8 in tender and swollen joint counts of 28 joints (scale 0=best to 28=worst) and 3 out of the following 5 measures: Health Assessment Questionnaire Disability Index (HAQ-DI) score (scale 0=no difficulty to 3=unable to do), subject global assessment (0=best to 10=worst), subject pain (0=no pain to 10=worst), evaluator's global assessment (0=best to 10=worst), or high sensitivity C-reactive protein (hsCRP) concentration (mg/mL).
Week 8
Change in Disease Activity Score-28 for Rheumatoid Arthritis with CRP (DAS28-CRP).
Time Frame: Week 8
Defined by EULAR based on a composite score of 4 items: tender and swollen joint counts of 28 joints (scale 0=best to 28=worst), subject global assessment (0=best to 10=worst) and high-sensitivity C-reactive protein (hsCRP) concentration (mg/L). DAS28-CRP response based on the minimal clinically important difference (MCID) of -1.2 from baseline to week 8.
Week 8
Change in Heath Assessment Questionnaire Disability Index (HAQ-DI)
Time Frame: Week 8
Haq-DI assesses physical function through eight daily activity domains (scale 0=no difficulty to 3=unable to do). Change from baseline to week 8 based on the MCID of -0.22.
Week 8
Change in Clinical Disease Activity Index (CDAI) score for Rheumatoid Arthritis
Time Frame: Week 8
The CDAI assesses disease activity by summing tender joint count (TJC), swollen joint count (SJC), patient global assessment (PGA), and physician global assessment (EGA). CDAI will be assessed from Baseline to Week 8.
Week 8
Change in Simplified Disease Activity Index (SDAI) for Rheumatoid Arthritis (RA)
Time Frame: Week 8
The SDAI is a measure of disease activity that includes all the 4 components of the CDAI, plus CRP. SDAI will be assessed from baseline to Week 8.
Week 8

Collaborators and Investigators

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

Sponsor

Surf Therapeutics

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)

January 1, 2026

Primary Completion (Estimated)

December 1, 2026

Study Completion (Estimated)

July 1, 2027

Study Registration Dates

First Submitted

December 2, 2025

First Submitted That Met QC Criteria

December 17, 2025

First Posted (Actual)

December 19, 2025

Study Record Updates

Last Update Posted (Actual)

January 23, 2026

Last Update Submitted That Met QC Criteria

January 22, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • SURF-CLN-003

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

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 Rheumatoid Arthritis (RA

Clinical Trials on Active treatment

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Indonesia

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe