PhaseⅢOpen-label Study of MRA for Rheumatoid Arthritis(RA)

Inclusion Criteria: * Diagnosed as having RA, on the basis of the criteria stipulated by the American Conference on Rheumatism(ACR) in 1987 * Active RA despite at least one DMARDs or immunosuppressants or Infliximab or Etanercept.Active disease is defined as having at least 6 tender and 6 swollen joints among DAS28 (Modified Disease Activity Scores that include twenty eight joint counts) and ESR at least 30 mm/hr or CRP not less than 2.0mg/dL * Active RA despite over 10mg adrenocortical steroids within 2 weeks before entry of this study Exclusion Criteria: * Shown to have class-Ⅳ Steinbrocker's functional activity in an evaluation carried out within 4 weeks before administration of the study drug * Treated with Infliximab within 3 months before and with Etanercept within 2 weeks before administration of the study drug * Subjected to any of the following within 4 weeks before administration of the study drug: 1. Surgical treatment (operations,etc.). 2. Plasma exchange method