MAUI, HAWAII – Arguably the most important development in the field of rheumatology during the past year was the emergence of persuasive clinical trials data predictive of a bright future for the oral Janus kinase inhibitors as major new drugs for treating ankylosing spondylitis, two experts agreed at the 2020 Rheumatology Winter Clinical Symposium.
Bruce Jancin/MDedge News
Dr. Eric M. Ruderman (left) and Dr. Arthur F. Kavanaugh
“These drugs are the first oral DMARDs [disease-modifying antirheumatic drugs], if you will, in AS [ankylosing spondylitis] ... I think obviously they are going to move forward to regulatory approval,” commented Arthur F. Kavanaugh, MD, professor of medicine at the University of California, San Diego, and the RWCS program director.
“I think they’re going to hit the ground running,” predicted Eric M. Ruderman, MD, professor of medicine and associate chief for clinical affairs in the division of rheumatology at Northwestern University, Chicago.
Upon approval, the Janus kinase (JAK) inhibitors will quickly change the treatment paradigm in AS, the rheumatologists forecast.
“I think this is a way forward to go with strictly oral therapy without necessarily going first with parenteral therapy in these patients. It gives you an alternative, and my guess is, by the time these drugs are approved in this space, there’ll be more and more of their preferential use over biologics in rheumatoid arthritis and potentially in psoriatic arthritis, so people will be more familiar with them. A lot of patients are much happier taking a pill once a day with none of the tolerability issues that we have with shots,” Dr. Ruderman said.
“And they act fast,” noted Dr. Kavanaugh. “You can make a case for trying a JAK inhibitor for a month or 2, and then if you’re not better, then we go to the other option.”
Dr. Ruderman cautioned that the increased need for laboratory monitoring with the oral JAK inhibitors as compared with the annual monitoring with tumor necrosis factor inhibitors could be an issue, especially since AS patients tend to be on the younger side and often dislike coming in regularly for office visits and laboratory tests.
“There may be more of a headache in having to tell patients, ‘You’re not getting your JAK inhibitor refilled until you get your labs done,’ ” he said.
In December 2019, rheumatologists received a holiday present in the form of publication of the results of SELECT-AXIS 1, a multicenter, double-blind, randomized, placebo-controlled phase 2/3 trial in which 187 patients with active AS were randomized to placebo or to the JAK inhibitor upadacitinib (Rinvoq) at the same 15-mg dose approved by the FDA earlier in the year for rheumatoid arthritis. In SELECT-AXIS 1, upadacitinib not only demonstrated clinical efficacy, with a week-14 Assessment of SpondyloArthritis International Society-40 (ASAS 40) response rate of 52% – twice that for placebo – but the active treatment arm also experienced significantly reduced inflammatory disease activity as measured by Spondyloarthritis Research Consortium of Canada (SPARCC) MRI scores of the spine and sacroiliac joint. In contrast, MRI scores remained unchanged from baseline in the placebo arm.
“This suggests a biologic effect, a hook beyond clinical disease. And the time of onset was pretty impressive, much like with our experience with JAK inhibitors in RA. Within 2 weeks, there was significant separation from placebo on the ASDAS [Ankylosing Spondylitis Disease Activity Score],” Dr. Ruderman noted.
Positive clinical trials in AS have also been reported for the oral JAK inhibitors filgotinib and tofacitinib (Xeljanz).
Dr. Ruderman and Dr. Kavanaugh also touched on other major developments in AS within the past year, including the landmark FDA approval of certolizumab pegol (Cimzia) as the first-ever drug for treatment of nonradiographic axial spondyloarthritis (nr-axSpA). Also, Dr. Kavanaugh and Dr. Ruderman gave two thumbs down to the 2019 Update of the American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network Recommendations for the Treatment of Ankylosing Spondylitis and Nonradiographic Axial Spondyloarthritis.