A Multicenter, Double-blind, Randomized, Placebo-controlled, Parallel-group Study to Assess the Efficacy and Safety of CDP870 in Patients With Early-stage Rheumatoid Arthritis Who Are Naïve to Methotrexate and Have Poor Prognostic Factors

The objective of this study is to assess the efficacy of certolizumab pegol (CZP) with methotrexate (MTX) compared with MTX-alone in patients with early-stage rheumatoid arthritis (RA) who are naive to MTX and have with poor prognostic factors, using inhibition of radiographically confirmed joint damage progression over a one-year period as a primary endpoint. Following a year of treatment with CZP plus MTX treatment, CZP will be discontinued, and the subjects will be monitored for one more year (the follow-up period) to investigate the sustainability of efficacy of CZP during the MTX monotherapy for exploratory purposes.