Prot# 104RA203: A Phs 2b, Rndmzd, Dbl-Blnd, Plcb-Cntrlld, Mltcntr Stdy to Evlut the Effcy, Sfty, Pharmacokinetics, and Pharmacodynamics of BG9924 When Gvn in Cmbntn w/ Methotrexate to Subs w/ Actv Rheumatoid Arthritis Who Have Had an Indqut Rspnd to Anti-