Study to Investigate the Efficacy, Safety, and Tolerability of FBL-MTX in Patients With Rheumatoid Arthritis

Inclusion Criteria:

• Male or non-pregnant female subjects with moderate-to-severe active RA, age ≥ 18years, Body Mass Index > 35 kg/m2.

• Diagnosis of RA according to the 2010 classification criteria of the AmericanCollege of Rheumatology/ European Alliance of Associations for Rheumatology,formerly known as European League Against Rheumatism, (ACR/EULAR), with a TotalScore ≥ 6/10.

• At least moderately active disease, as defined by DAS28-CRP >3.2 at Screening andBaseline, including:

• Tender joint count (TJC) ≥ 4

• Swollen joint count (SJC) ≥ 4

• C Reactive protein (CRP) ≥ 5 mg/L

• Documented history of positive RA factor and/or cyclic citrullinated peptideantibody test.

• Chest X-ray performed in the previous 3 months not suggestive of tuberculosis.

• If under nonsteroidal anti-inflammatory drugs (NSAIDs), must be able to be on astable regimen from at least 2 weeks before baseline up to end-of-study.

• If under an oral corticosteroid (≤ 10 mg per day of prednisone or equivalent), mustbe able to be on a stable regimen from at least 4 weeks before baseline up to EoS.

• Eligible to start treatment with an immunomodulator.

• No evidence of clinically significant active infection.

Exclusion Criteria:

• Positive Interferon-Gamma Release Assay (IGRA) test result.

• Creatinine clearance < 60 mL/min.