Effects of Administration of SCFA in Rheumatoid Arthritis Inadequate Responders

This study is a pilot, proof of concept study to determine the effects of administering an oral short-chain fatty acid (SCFA) supplement to Rheumatoid Arthritis (RA) patients with inadequate response to methotrexate (MTX). The study will include up to 35 participants to obtain a sample size of at least 25 participants taking the oral supplement. The researchers hypothesize that oral SCFA will change the participants' gut microbiome and regulatory immune responses. Clinical data to assess for adverse events, stool, urine samples and peripheral blood will be collected at baseline, 1 month, and with an optional 2 month time-point. Fecal microbiome will be analyzed. Adaptive immune responses will be analyzed from participant blood samples.

Inclusion Criteria:Diagnosis of RA meeting 2010 ACR/EULAR for RA and/or treating MD diagnosisInadequate response to MTX per treating MD at maximum tolerated dose.Able and willing to provide written informed consent prior to any study specific proceduresAge 18 years and above at time of enrollmentSubjects not excluded based on race or ethnicityExclusion Criteria:Participants who are pregnant or are currently breastfeedingHistory of sensitivity to study compound or any of their excipientsPrevious intolerance to SCFA or related compoundsCurrent antibiotic treatment (within 3 months of screening) at discretion of PICurrent consumption of probiotics (within 3 months of screening) at discretion of PISevere hepatic impairment (eg, ascites and/or clinical signs of coagulopathy)Renal failure (eGFR <30 or requiring dialysis) by historyHistory of other autoimmune disease at discretion of PICurrent immunodeficiency state (e.g., cancer, HIV, others)