A Multicenter, Open-label, Long-term Follow-up Safety and Efficacy Study of GLPG0634 Treatment in Subjects With Moderately to Severely Active Rheumatoid Arthritis

The primary objective of the study was to evaluate the long-term safety and tolerability of filgotinib (formerly GLPG0634) for the treatment of rheumatoid arthritis.Participants were enrolled in this open-label long-term follow-up study after they had completed one of the two core studies, GLPG0634-CL-203 (DARWIN1) (NCT01888874) or GLPG0634-CL-204 (DARWIN2) (NCT01894516), and were evaluated for any side effects that might have occured (long-term safety and tolerability) when taking filgotinib. During the course of the study, participants were also examined for long-term effects of filgotinib administration on disease activity (efficacy), participant's disability, fatigue, and quality of life.