Abstract
OBJECTIVE: Upadacitinib improved the signs and symptoms of non-radiographic axial spondyloarthritis (nr-axSpA) versus placebo over 14 weeks in the primary analysis of the SELECT-AXIS 2 nr-axSpA study. Here, we evaluated the efficacy and safety of upadacitinib through 1 year in patients with nr-axSpA in SELECT-AXIS 2. METHODS: Patients aged at least 18 years diagnosed with nr-axSpA who fulfilled the 2009 Assessment of SpondyloArthritis International Society (ASAS) classification criteria and were receiving stable background therapy were randomized to upadacitinib 15 mg once daily or placebo for the 52-week double-blind period. Efficacy was assessed using non-responder imputation incorporating multiple imputation (NRI-MI) and as-observed analyses for binary endpoints, and mixed-effects model repeated measures for continuous endpoints. RESULTS: Of 314 randomized patients, 259 (upadacitinib, n = 129; placebo, n = 130) completed 52 weeks of treatment. More patients receiving upadacitinib versus placebo achieved ≥40% improvement in ASAS at week 52 (63% vs 43%, NRI-MI; nominal P < 0.001). Similar treatment effects were observed for the achievement of axSpA Disease Activity Score inactive disease (33% v 11%, NRI-MI; nominal P < 0.001). Overall, patients receiving upadacitinib versus placebo showed greater improvement in disease activity, inflammation, pain, function, enthesitis, and quality of life through 52 weeks. Adverse events were generally comparable between the treatment groups. No opportunistic infections, malignancies, major adverse cardiovascular events, venous thromboembolic events, inflammatory bowel disease, or deaths were reported in those receiving upadacitinib. CONCLUSION: Treatment with upadacitinib showed sustained efficacy versus placebo with no new safety findings identified through 1 year. These results support the continued favorable benefit-risk profile of upadacitinib treatment for nr-axSpA.