Study of Adalimumab in Patients With Axial Spondyloarthritis

This study will evaluate how well adalimumab works in the short and long term in patients with axial spondyloarthritis who are not diagnosed as having either ankylosing spondylitis or psoriatic arthritis.

This is a Phase 3, placebo-controlled, double-blind randomized study with an open-label phase designed to evaluate the efficacy and safety of adalimumab 40 mg administered every other week in adult patients with active axial spondyloarthritis (SpA) who are not diagnosed with ankylosing spondylitis, psoriasis, or psoriatic arthritis and who have had an inadequate response or intolerance to one or more nonsteroidal anti-inflammatory drugs (NSAIDs) or had a contraindication to NSAIDs. Participants receive adalimumab or placebo for 12 weeks during the double-blind phase of the study. Following the double-blind phase, all remaining participants enter the open-label phase of the study in which they receive open-label adalimumab for up to 144 weeks. Efficacy endpoints include the Assessment of Spondyloarthritis International Society (ASAS) response criteria for patients with SpA. These response criteria were used to determine participants who were responders. ASAS response involves evaluations in the following 4 domains: participant's global assessment of disease activity, pain, function, and inflammation. The patient's global assessment of disease activity score is assessed using a 100 millimeter (mm) visual analog scale (VAS; 0 for no disease activity to 100 for severe disease activity). Pain is represented as a total back pain score and is assessed using a 100 mm VAS (0 for no pain to 100 for most severe pain). Function score is represented as the Bath Ankylosing Spondylitis (AS) Functional Index (BASFI) 100 mm VAS score (average of the ability to perform 10 activities, each scored as 0 for easy to 100 for impossible). Inflammation is determined using the morning stiffness overall level score (0 for none to 10 for very severe) and duration score (0 for 0 hours to 10 for ≥ 2 hours) of the Bath AS Disease Activity Index (BASDAI) (mean of these items #5 and #6 scores). In addition, the BASDAI is used as an efficacy endpoint. The BASDAI is used by the participant to assess his/her disease activity. Using VAS scales, the participant answers 6 questions pertaining to symptoms experienced over the past week. For 5 questions (levels of: fatigue/tiredness; AS neck, back, or hip pain; pain/swelling; discomfort at areas tender to touch or pressure; and morning stiffness), the response scale is 0 (none) to 10 (very severe). For 1 question (duration of morning stiffness), the response scale is 0 (0 hours) to 10 (≥ 2 or more hours).

Eligibility Criteria:
Inclusion Criteria:

* Adult patients with inadequate response to \>/= 1 non-steroidal anti-inflammatory drugs (NSAIDs)
* Chronic back pain with onset \< 45 years of age
* Magnetic resonance imaging (MRI) indicating active sacroiliitis or positive human leukocyte antigen-B27 (HLA-B27) blood test in addition to meeting spondyloarthritis clinical criteria
* Negative purified protein derivative (PPD) test and chest x-ray performed at Baseline visit must be negative
* Ability to administer subcutaneous injections
* General good health otherwise

Exclusion Criteria:

* Prior anti-tumor necrosis factor (TNF) therapy
* Psoriasis or psoriatic arthritis
* Fulfillment of modified New York criteria for ankylosing spondylitis
* Recent infection requiring treatment
* Significant medical events or conditions that may put patients at risk for participation
* Females who are pregnant or breast-feeding or considering becoming pregnant during the study
* History of cancer, except successfully treated skin cancer
* Recent history of drug or alcohol abuse