• Participant or legally authorized representative must be able to understand and provide informed consent

• Adults ≥ 18 years of age

• Diagnosed with RA by fulfilling the ACR/EULAR 2010 Classification Criteria for RA ≥ 6 months prior to screening (Appendix 9)

• Documented positive test for rheumatoid factor (RF) and/or anti-cyclic citrullinated peptide antibody (ACPA)

• SDAI ≥ 17

• At least 4 tender and 4 swollen joints by a 44 joint count (Appendix 5)

• Receiving treatment with an FDA-approved TNFi (including biosimilars) that is dosed subcutaneously at an FDA-approved dosing regimen for at least 12 weeks.

• Willing to continue or discontinue treatment with their current TNFi at the same dose depending upon study arm assignment

• If treated with leflunomide, sulfasalazine, or hydroxychloroquine, must be taking a stable dose for at least 12 weeks

⁃ If treated with methotrexate, must be taking a stable dose for at least 12 weeks. The following exceptions are permitted within the 12 weeks prior to screening:

∙ Holding methotrexate after COVID-19 vaccination as per American College of Rheumatology guidance (https://rheumatology.org/)

‣ Holding methotrexate for 1 or 2 weeks after influenza vaccination

⁃ All participants who engage in sexual activity that could lead to pregnancy must agree to use abstinence or an FDA-approved contraception for the duration of the study to prevent pregnancy