A Study Evaluating the Safety and Efficacy of Upadacitinib in Adults With Active Ankylosing Spondylitis

This study includes two periods: a 14-week double-blind placebo-controlled period and a 90-week open-label long-term extension period. Eligible participants were randomly assigned in a 1:1 ratio to receive upadacitinib 15 mg or placebo for 14 weeks in Period 1. Participants who completed Period 1 received upadacitinib 15 mg for 90 weeks in the extension period.