Ultrasound Neuroimmune Modulation in Adults With Rheumatoid Arthritis (SUSTAIN)

Surf Therapeutics

Status and phase: Enrolling; Phase 2

Conditions: Rheumatoid Arthritis (RA

Treatments: Device: Active treatment; Device: Sham (No Treatment)

Study type: Interventional

Funder types: Industry

Identifiers

NCT07293871

SURF-CLN-003

Details and patient eligibility

About

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.

Full 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.

Enrollment: 40 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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40 participants in 2 patient groups

Treatment

Experimental group

Description:

Daily active stimulation for 8 weeks

Treatment:

Device: Active treatment

Control

Sham Comparator group

Description:

Daily sham stimulation, for 8 weeks, which will look and feel the same as active stimulation, but with no ultrasound energy entering the body

Treatment:

Device: Sham (No Treatment)