A Study to Assess the Effects of Certolizumab Pegol on the Reduction of Anterior Uveitis (AU) Flares in Axial Spondyloarthritis Subjects With a Documented History of AU

Inclusion Criteria:

• Subjects must have a documented diagnosis of adult-onset axial Spondyloarthritis (axSpA) with at least 3 months' symptom duration and meet the Assessment ofSpondyloArthritis International Society (ASAS) criteria
• Subjects must have active disease at Screening as defined by
• Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score >= 4
• Spinal pain >= 4 on a 0 to 10 Numerical Rating Scale (NRS; from BASDAI item 2)
• Nonradiographic (Nr)-axSpA subjects must either have C-reactive protein (CRP) > upperlimit of normal (ULN) and /or current evidence of sacroiliitis on magnetic resonanceimaging (MRI) (no confirmation by central reading) as defined by ASAS criteria
• Ankylosing spondylitis (AS) subjects must have evidence of sacroiliitis on x-raymeeting the modified New York (mNY) classification criteria according to theInvestigator
• Subjects must have a documented history of Anterior Uveitis (AU) diagnosed by anophthalmologist and have at least 2 AU flares in the past, of which at least 1 AUflare was in the last 12 months prior to Baseline

Exclusion Criteria:

• Other inflammatory arthritis
• Secondary, noninflammatory condition that, in the Investigator's opinion, issymptomatic enough to interfere with evaluation of the effect of study drug on thesubject's primary diagnosis of axial spondyloarthritis (axSpA)
• Any history of uveitis except for Anterior Uveitis (AU) associated with axSpA
• Any condition or complicating factor that may interfere with the AU assessment
• Retisert® or Iluvien® (glucocorticosteroid implant) within 3 years prior to theBaseline Visit or has had complications related to the device
• Subject has had Retisert or Iluvien (glucocorticosteroid implant) removed within 90days prior to the Baseline Visit
• Intraocular or periocular corticosteroids within 90 days prior to the Baseline visit
• Ozurdex® (dexamethasone implant) within 6 months prior to the Baseline Visit
• Cyclophosphamide within 30 days prior to the Baseline Visit
• Intravitreal methotrexate (MTX) within 90 days prior to the Baseline Visit
• Intravitreal anti-vascular endothelial growth factor (VEGF) therapy