Study to Assess if ABP 798 is Safe & Effective in Treating Moderate to Severe Rheumatoid Arthritis (RA) Compared to Rituximab

Inclusion Criteria

• Men or women ≥ 18 and ≤ 80 years old
• Subjects must be diagnosed with rheumatoid arthritis for at least 6 months before baseline
• Active RA defined as ≥ 6 swollen joints and ≥ 6 tender joints at screening and baseline and at least one of the following at screening:
• erythrocyte sedimentation rate (ESR) ≥ 28 mm/hr
• serum C-reactive protein (CRP) > 1.0 mg/dL
• Subjects must be taking methotrexate (MTX) for ≥ 12 consecutive weeks and on a stable dose of MTX 7.5 to 25 mg/week for ≥ 8 weeks prior to receiving the investigational product (IP), and be willing to remain on a stable dose throughout the study
• Subject has no known history of active tuberculosis

Exclusion Criteria

• Class IV RA, Felty's syndrome or history of prosthetic or native joint infection
• Major chronic inflammatory disease or connective tissue disease other than RA, with the exception of secondary Sjögren's syndrome
• Use of commercially available or investigational biologic therapies for RA as follows:
• anakinra, etanercept within 1 month prior to first dose of IP
• infliximab, abatacept, tocilizumab, golimumab, certolizumab within 3 months prior to first dose of IP
• other experimental or commercially available biologic therapies for RA within 3 months or 5 half-lives (whichever is longer) prior to first dose of IP
• Previous receipt of rituximab or a biosimilar of rituximab

Other Inclusion/Exclusion criteria may apply