Safety and Efficacy of Filgotinib: Up to 4-Year Results From an Open-Label Extension Study of Phase 2 Rheumatoid Arthritis Programs. The Journal of rheumatology Kavanaugh, A., Westhovens, R. R., Winthrop, K. L., Lee, S. J., Tan, Y., An, D., Ye, L., Sundy, J. S., Besuyen, R., Meuleners, L., Stanislavchuk, M., Spindler, A. J., Greenwald, M., Alten, R., Genovese, M. C. 2021

Abstract

OBJECTIVE: The long-term safety and efficacy of filgotinib (from phase 2 studies), with or without methotrexate (MTX), for the treatment of patients with rheumatoid arthritis was assessed in DARWIN 3, a long-term, open-label extension study (NCT02065700).METHODS: Eligible patients completing the 24-week DARWIN 1 (filgotinib + MTX) and DARWIN 2 (filgotinib monotherapy) studies entered DARWIN 3, where they received filgotinib 200 mg/day, except for 15 men who received filgotinib 100 mg/day. Safety analyses were performed using the safety analysis set and exposure-adjusted incidence rate (EAIR) of treatment-emergent adverse events (TEAEs) was calculated. Efficacy was assessed from baseline in the parent studies.RESULTS: Of 790 patients completing the phase 2 parent studies, 739 enrolled in the study. Through April 2019, 59.5% of patients had received =4 years of study drug. Mean (SD) exposure to filgotinib was 3.55 (1.57) years in the filgotinib + MTX group and 3.38 (1.59) years in the filgotinib monotherapy group. EAIR per 100 patient years of exposure (PYE) for TEAEs was 24.6 in the filgotinib + MTX group and 25.8 in the filgotinib monotherapy group, and for serious TEAEs, the EAIR was 3.1 and 4.3, respectively. ACR20/50/70 responses among patients remaining in the study could be maintained through 4 years, with 89.3%/69.6%/49.1% of filgotinib + MTX group and 91.8%/69.4%/44.4% of monotherapy group maintaining ACR20/50/70 responses based on observed data.CONCLUSION: Filgotinib was well tolerated with a 4-year safety profile comparable to that of the parent trials, both in patients receiving combination therapy with MTX or as monotherapy.

View details for DOI 10.3899/jrheum.201183

View details for PubMedID 33526618