The research objective of the pilot study is to assess early feasibility of safety and efficacy of spleen ultrasound stimulation in the treatment of rheumatoid arthritis (RA) in a blinded and randomized controlled trial. Specific Aims include:

• Measure RA disease activity and functional/biomarker metrics during and after a 2- week course of spleen-directed daily ultrasound treatments (within-arm and between-arm assessments); and
• Monitor adverse events during and after daily ultrasound treatments.

Inclusion Criteria:

1. Males and Females aged 18 and over.

2. Must carry a diagnosis of rheumatoid arthritis, as defined by the American College of Rheumatology in 2010: (https://www.rheumatology.org/Portals/0/Files/2010\_revised\_criteria\_classification\_ra.pdf).

   Classification as "definite RA" is based on the confirmed presence of synovitis in at least one joint, absence of an alternative diagnosis that better explains the synovitis, and achievement of a total score of 6 or greater (of a possible 10) from the individual scores in 4 domains: number and site of involved joints (score range 0-5), serologic abnormality (score range 0-3), elevated acute-phase response (score range 0-1), and symptom duration (2 levels; range 0-1).

3. Exhibiting symptoms or signs of inadequate disease control according to one of 2 measures:

   Modified HAQ score of greater than 0.3 and DAS28-CRP greater than 3.2 (http://www.phusewiki.org/wiki/index.php?title=Disease\_Activity\_Score\_-\_CRP\_(DAS-CRP).

4. Participants should have home access to broadband internet, such that online video conversations can occur with study personnel via study-provided personal digital assistive devices.

Exclusion Criteria:

1. Active bacterial or viral infection.
2. Pregnant women or presence of active malignancy.
3. Inability to perform minimal daily self-cares associated with feeding/dressing, according to HAQ.