A Study to Evaluate Efficacy and Safety of Upadacitinib in Adults With Axial Spondyloarthritis

Study 1 (bDMARD-IR AS) is comprised of a 14-week randomized, double-blind, parallel-group, placebo-controlled period (the Double-Blind Period); a 90-week open-label, long-term extension period (the Open-Label Extension Period); and a 30-day Follow-Up Visit (F/U Visit). Study 2 (nr-axSpA) is comprised of a 52-week randomized, double-blind, parallel-group, placebo-controlled period (the Double-Blind Period); a 52-week open-label, long-term extension period (the Open-Label Extension Period); and a 30-day F/U Visit. In the Double-Blind Period for both studies, participants are randomized in a 1:1 ratio to receive either upadacitinib or placebo once daily (QD). Participants in the placebo group switch to upadacitinib 15 mg QD at Week 14 in the Open-Label Extension Period for Study 1 (bDMARD-IR AS) and Week 52 in the Open-Label Extension Period for Study 2 (nr-axSpA). Participants in remission at Week 104 have the option to enroll in a remission-withdrawal period. Study M19-944 protocol uses a common screening platform for determining eligibility into Study 1 and Study 2. Each study has its own objectives, hypothesis testing, randomization, data collection, and adequate power for primary and secondary endpoints. Analysis and reporting are conducted separately and independently for each study.