Evaluation of the Effectiveness and Safety of Two Dosing Regimens of Olokizumab (OKZ), Compared to Placebo and Adalimumab, in Subjects With Rheumatoid Arthritis (RA) Who Are Taking Methotrexate But Have Active Disease

Evaluation of the Effectiveness and Safety of Two Dosing Regimens of Olokizumab (OKZ), Compared to Placebo, in Subjects With Rheumatoid Arthritis (RA) Who Are Taking an Existing Medication Called a Tumour Necrosis Factor Alpha Inhibitor But Have Active Disease

Evaluation of the Long Term Safety, Tolerability and Efficacy of Two Dosing Regimens of Olokizumab (OKZ), in Subjects With Rheumatoid Arthritis (RA) Who Previously Completed 24 Weeks of Blinded Treatment in One of the Core Studies - CREDO 1, 2 or 3.