A Study to Assess the Effect of Tocilizumab + Methotrexate on Signs and Symptoms in Patients With Moderate to Severe Active Rheumatoid Arthritis

This 3 arm study will compare the safety and efficacy, with regard to reduction of signs and symptoms, of tocilizumab versus placebo, both in combination with methotrexate (MTX). in patients with moderate to severe active rheumatoid arthritis (RA) who currently have an inadequate response to MTX. Patients wil be randomized to receive tocilizumab 4mg/kg iv, tocilizumab 8mg/mg iv, or placebo iv, every 4 weeks; all patients will also receive methotrexate 10-25mg weekly. The anticipated time on study treatment is 3-12 months, and the target sample size is 500+ individuals.