A New, Non-Biologic Medication Option Being Tested For Those With Active Ankylosing Spondylitis: Results From a Phase 2 Clinical Trial for Filgotinib, a Selective Jack 1 Inhibitor.

By Spondylitis Association of America

Tuesday, January 29, 2019

A phase 2 clinical trial assessed the effectiveness and safety of an oral medication, Filgotinib, in patients with active ankylosing spondylitis (AS) who have not responded adequately to, or have been intolerant of, two or more non-steroidal anti-inflammatory drugs (NSAIDs). The medication, Filgotinib - a selective Janus Kinase 1 (JAK1) inhibitor - is classified as a small molecule Disease-Modifying Anti-Rheumatic Drug (DMARD), rather than a biologic, and works by very specifically targeting and inhibiting the JAK1 enzyme’s inflammatory activity. Participants were recruited from seven countries (Belgium, Bulgaria, Czech Republic, Estonia, Poland, Spain, and Ukraine) with a mean age of 41. The 116 screened and selected study participants were assigned to two groups, the Filgotinib group and placebo group. Participants in the Filgotinib group were given a daily dose of 200mg of Filgotinib, while the placebo group received 200mg of an inactive substance (sugar pill).

The Ankylosing Spondylitis Disease Activity Score (ASDAS) was used to assess disease activity in the participants. The report showed major improvements in ASDAS scores in 33% of those in the Filgotinib group vs in 2% of those enrolled in the placebo group, a significant difference between the two groups. In addition, the ASAS-20 (ASAS Response Criteria) which is defined as an overall improvement of at least 20%, was achieved by 76% of those taking the active medication, vs 40% of those in the placebo group. Lastly, the ASAS-40, which designates an overall improvement of at least 40%, was achieved by 38% of those in the active medication group, and 19% of those in the placebo group.

There were no reports of the disease worsening, no additional new involvement outside the joint, infections caused by pathogens, active tuberculosis, or death. However, 18 participants from each group reported treatment side effects: upper respiratory infections, or rhinitis being the most common. Furthermore, 1 patient from each group had to withdraw from the study due to adverse reactions.

The authors are hopeful that further clinical studies using larger samples and long-term clinical trials for Filgotinib will yield a new and promising treatment option for those living with ankylosing spondylitis. As currently, the only treatment recommended for those with AS who don’t respond to NSAIDs are biologic medications (TNF and IL inhibitors) this would be a big step forward in the quest for new and varied treatment options.


***Dr. Atul Deodhar and Dr. Lianne Gensler, members of SAA’s Medical and Scientific Board, were contributing writers on this study.


Further reading:




van der Heijde D, Baraliakos X, Gensler LS, et al. Efficacy and safety of filgotinib, a selective Janus kinase 1 inhibitor, in patients with active ankylosing spondylitis (TORTUGA): results from a randomized, placebo-controlled, phase 2 trial [published online October 22, 2018]. Lancet. doi:10.1016/s0140-6736(18)32463-2

Rothbard, G., MD, MS. (2018, November 29). Filgotinib Safe, Effective for Treatment of Active Ankylosing Spondylitis. Retrieved from https://www.rheumatologyadvisor.com/spondyloarthritis/ankylosing-spondylitis-filgotinib-treatment-efficacy/article/817364/




Stay Informed



Visit our careers page for available positions

Contact Us

Spondylitis Association of America

16360 Roscoe Blvd.  Ste. 100
Van Nuys, CA 91406



Information Requests

(800) 777-8189 U.S. only
or (818) 892-1616
*Please note: This is not a Crisis Hotline. If you are in a life-threatening crisis, please dial 911 for immediate help in the US. Please follow this link for crisis intervention resources.

Give With Confidence