Study design
REMISSION, DISEASE
Full details of the study design have been published previously [Study design. An IP of 56 weeks was followed by a 48-week DE period for patients in sustained SDAI remission (≤ 3.3 at both weeks 40 and 52 in the IP) and a 24-week post-treatment follow-up period (all patients). DE, de-escalation; EOW, every other week; IP, induction period; MTX, methotrexate; OL, open-label; QW, once-weekly; SC, subcutaneous; SDAI, Simplified Disease Activity Index; Wk, week. Patients who completed the IP and achieved sustained SDAI remission (≤ 3.3 at both weeks 40 and 52) entered a 48-week DE period. Patients entering the DE period who were originally treated with abatacept + MTX were re-randomized (1:1:1) to one of three abatacept treatment arms: continuation (abatacept QW + MTX for 48 weeks); stepwise DE and withdrawal (abatacept every other week [EOW] + MTX for 24 weeks [part 1] followed by abatacept placebo + MTX for 24 weeks [part 2]); or abatacept monotherapy (abatacept QW + MTX placebo for 48 weeks) (Fig. The study was conducted in accordance with the Declaration of Helsinki and International Conference on Harmonisation Good Clinical Practice. The protocol and patients’ informed consent received institutional review board/independent ethics committee approval prior to initiation of the study, and all patients provided informed consent prior to enrollment.