ACR 2019


Conference summaries

Rheumatoid Arthritis

Rheumatoid Arthritis Treatment with Filgotinib: Week 156 Safety and Efficacy Data from a Phase 2b Open-Label Extension Study

Presented by: Arthur Kavanaugh, MD
University of California, San Diego School of Medicine, La Jolla, CA, USA
  • After 156 weeks of treatment, filgotinib, a highly selective JAK1 inhibitor, was generally well tolerated and no new safety signals emerged, with no safety differences in patients receiving combination therapy with methotrexate (MTX) vs. filgotinib monotherapy.
  • Efficacy was sustained up to week 156 in both monotherapy and in MTX combination groups.

Filgotinib (FIL) is an oral selective JAK1 inhibitor. In studies to date, FIL was found to be effective and safe in patients with rheumatoid arthritis (RA). [1,2] DARWIN 3 is an ongoing, open-label, long-term extension study of earlier phase 2b studies evaluating the long-term outcomes with FIL in RA.

  • To evaluate the long-term safety and efficacy of FIL in RA.
  • All patients who were inadequate responders to MTX completing the 24-week DARWIN 1 (FIL + MTX) and DARWIN 2 (FIL monotherapy) studies were eligible to enter DARWIN 3.
  • Week 156 interim analysis data from the first dose of FIL in the parent studies through 30 May 2018 is presented.
  • Patients were analyzed by FIL + MTX (from DARWIN 1) or FIL monotherapy (from DARWIN 2).
  • The event rate was calculated as the total events/total years of exposure of FIL. If the subjects were continuing the study at the time of analysis, the exposure was calculated up to the data cut date.
  • Of 877 patients completing the parent studies, 739 patients enrolled in DARWIN 3 (497 from DARWIN 1, 242 from DARWIN 2); the majority of patients in DARWIN 1 and 2 were female (81.5%, 81.8%) and white (75.3%, 74.8%) with a mean age of 53 and 52 years, respectively.
  • The mean baseline MTX dose in the FIL + MTX group was 16.8 mg/week.
  • At week 156, 59.9% of patients remained on study treatment.
  • The most common reasons for discontinuation were adverse events (26.5%) and subject request (9.1%).
  • Total exposure to FIL was 2203 patient years; mean ± standard deviation (SD) exposure was 2.86 ± 1.21 years for FIL + MTX and 3.04 ± 1.22 years for FIL monotherapy.
  • Treatment-emergent adverse events (TEAEs) occurred in 419 (84.3%) and 203 (83.9%) patients receiving FIL + MTX and FIL monotherapy; serious TEAEs occurred in 45 (9.1%) and 33 (13.6%), respectively.
  • Event rates of adverse events of special interest, such as serious infections and Herpes zoster infections, remained low at week 156.
  • There were 5 deaths (meningococcal meningitis, pneumonia, non-Hodgkin’s lymphoma, and deep vein thrombosis with pulmonary embolism); none occurred after the week 132 analysis (2 in FIL + MTX; 3 in FIL monotherapy).
  • Clinical efficacy up to week 156, as measured by ACR20/50/70 responses, and DAS28(CRP) ≤3.2 and DAS28(CRP) <2.6 are shown in the Figure.
  • FIL was generally well tolerated, and no new safety signals emerged after 156 weeks of treatment.
  • No differences regarding safety emerged in patients receiving combination therapy with MTX vs. FIL monotherapy.
  • Efficacy is sustained up to week 156 in both the monotherapy and MTX combination groups.

Key messages/Clinical perspectives

  • These data add information on the efficacy and safety of FIL as monotherapy and in combination with MTX.


Trial: NCT02065700



  1. Westhovens R, Taylor PC, Alten R, et al. Filgotinib (GLPG0634/GS-6034), an oral JAK1 selective inhibitor, is effective in combination with methotrexate (MTX) in patients with active rheumatoid arthritis and insufficient response to MTX: results from a randomised, dose-finding study (DARWIN 1). Ann Rheum Dis. 2017 Jun;76(6):998-1008.
  2. Kavanaugh A, Kremer J, Ponce L, et al. Filgotinib (GLPG0634/GS-6034), an oral selective JAK1 inhibitor, is effective as monotherapy in patients with active rheumatoid arthritis: results from a randomised, dose-finding study (DARWIN 2). Ann Rheum Dis. 2017 Jun;76(6):1009-19.

Presenter disclosure: The presenter has reported relationships with Abbott, Amgen, AstraZeneca, Bristol-Myers Squibb, Celgene, Centocor-Janssen, Eli Lilly, Gilead Sciences, Janssen, Janssen Research & Development, LLC, Novartis, Pfizer, Roche, UCB Pharma.

Written by: Patrick Moore, PhD

Reviewed by: Alessia Alunno, MD, PhD

Local reviewers: Alessia Alunno, MD, PhD (Italian); Aurélie Najm, MD (French); Yukinori Okada, MD, PhD (Japanese); Fabian Proft, MD (German); Javier Rodríguez-Carrio, MSc, PhD (Spanish); Priscilla Wong, MD (Chinese)

Scientific Editor:  Leonard H. Calabrese, DO


A Comparative Analysis of Upadacitinib Monotherapy and Upadacitinib Combination Therapy for the Treatment of Rheumatoid Arthritis from Two Phase 3 Trials

Presented by: Maya H. Buch, MD, PhD - University of Leeds & NIHR Leeds Biomedical Research Centre, Leeds, United Kingdom

Rheumatoid Arthritis Treatment with Filgotinib: Week 156 Safety and Efficacy Data from a Phase 2b Open-Label Extension Study

Presented by: Arthur Kavanaugh, MD - University of California, San Diego School of Medicine, La Jolla, CA, USA


A Phase 1b/2a Trial of Tofacitinib, an Oral Janus Kinase Inhibitor, in Systemic Lupus Erythematosus

Presented by: Sarfaraz Hasni, MD - National Institute of Arthritis, Musculoskeletal, and Skin diseases/ National Institutes of Health, Bethesda, MD, USA

A Phase 3 Randomized Controlled Trial of Anifrolumab in Patients with Moderate to Severe Systemic Lupus Erythematosus

Presented by: Richard A. Furie, MD - Zucker School of Medicine at Hofstra/Northwell, New York, NY, USA


The Burden of Comorbidity in Patients with RA, PsA or SPA in a General Practice Registry

Presented by: Diederik De Cock, PhD - KU Leuven, Leuven, Belgium



Ixekizumab Demonstrates Improvement Comparable to Adalimumab Across ACR Components in Biologic-Naïve Patients with Psoriatic Arthritis

Presented by: M. Elaine Husni, MD, MPH - Dept. of Rheumatologic and Immunologic Diseases, Cleveland Clinic, Cleveland, OH, USA

Tildrakizumab Efficacy on Psoriasis in Patients with Psoriatic Arthritis—An Analysis from a Phase 2 Study

Presented by: Alan M. Mendelsohn, MD - Sun Pharmaceutical Industries, Inc., Princeton, NJ, USA, Princeton, NJ, USA

Development of a Set of ASAS Quality Standards for Adults with Axial Spondyloarthritis

Presented by: Uta Kiltz, MD - Rheumazentrum Ruhrgebiet/Ruhr University Bochum, Herne, Germany

Ixekizumab in Non-Radiographic Axial Spondyloarthritis: Primary Results from a Phase 3 Trial

Presented by: Atul Deodhar, MD, MRCP - Oregon Health & Science University, Portland, OR, USA


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