In this Phase 2b study in patients with moderate to severe RA, once-daily peficitinib in combination with limited csDMARDs reduced the symptoms of RA, demonstrated adose-dependent ACR20 response rate over 12 weeks, and showed acceptable tolerability. This 12-week study included patients who had an inadequate response or intolerance to csDMARDs (N=289). Patients were randomised 1:1:1:1:1 to peficitinib 25-, 50-, 100, 150 mg or matching placebo. Statistically significant differences in the ACR20 r...