Multicenter Study Evaluating Certolizumab Pegol Compared to Placebo in Subjects With axSpA Without X-ray Evidence of AS

Inclusion Criteria: * At least 18 years old at the start of Screening Visit * A documented diagnosis of adult-onset axial SpondyloArthritis (axSpA) and meet the Assessment of SpondyloArthritis International Society (ASAS) criteria for axSpA * Subjects must have had back pain for at least 12 months before Screening * No sacroiliitis defined by Modified New York (mNY) criteria on sacroiliac (SI) x-rays * 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) * Inadequate response to, have a contraindication to, or have been intolerant to at least 2 Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) Exclusion Criteria: * Diagnosis of AS or any other Inflammatory Arthritis * Prior treatment with any experimental biological agents for treatment of Axial SpondyloArthritis (SpA) * Exposure to more than 1 tumor necrosis factor (TNF)-antagonist or primary failure to TNF antagonist therapy * History of or current chronic or recurrent infections * Subjects with known Tuberculosis (TB) infection, at high risk of acquiring TB infection, or latent Tuberculosis (LTB) * Recent live vaccination * Concurrent malignancy or a history of malignancy * Class III or IV congestive heart failure - New York Heart Association (NYHA) * Demyelinating disease of the central nervous system * Female subjects who are breastfeeding, pregnant or plan to become pregnant during the study o…