This Phase IIIb, randomized, multi-national, multi-center, blinded study of Infliximab (IFX) in subjects aged 18 and older with active RA is being conducted to assess whether increasing either the infusion dose or infusion frequency in patients presenting with a disease flare after an initial response to infliximab results in a significant improvement in disease activity.||Subjects responding to an initial infliximab treatment regimen, who flare during continuation of treatment at 3 mg/kg administered every 8 weeks, will be randomly assigned to one of 3 different dosing regimens of infliximab and will be treated for 4 or 5 consecutive infusions for a total duration of 24 weeks. The infliximab control group and the infliximab increased dose group are evaluator and subject-blinded. The increased frequency group is not blinded. Clinical assessments of disease activity will be based the European League Against Rheumatism (EULAR) criteria for response. Safety parameters will be assessed at every infusion.||A disease flare is defined by an increase in DAS28 with 0.6 or more at screening, when compared to the DAS28 score measured immediately prior to the last Remicade® infusion and depends upon the actual score as well. Since prior to enrollment, the subject received Remicade® as per routine clinical practice, the days on which infusions were administered and assessments are done during the induction period do not have to be exactly at Week 2, 6 and 14.||Drug: Infliximab Control (double-blinded)|Drug: Infliximab Increased Dose (double-blinded)|Drug: Infliximab Increased Frequency (open-label)