A Ph II/III Seamless, Multi-center, Randomized, Double-blind, Placebo-controlled Study of the Reduction in Signs and Symptoms and Inhibition of Structural Damage During Treatment With Tocilizumab Versus Placebo in Patients With Ankylosing Spondylitis Who Have Failed Non-steroidal Anti-inflammatory Drugs and Are naïve to TNF Antagonist Therapy NSAIDs

Inclusion Criteria

Inclusion Criteria

- Adult patients, ≥ 18 years of age

- Ankylosing Spondylitis as defined by the modified New York criteria for ≥ 3 months
prior to baseline

- Active disease at screening and baseline (Bath Ankylosing Spondylitis Disease
Activity Index [BASDAI] ≥4.0, spinal pain visual analog scale [VAS] ≥40)

- Inadequate response or intolerant to 1 or more previous non-steroidal
anti-inflammatory drugs (NSAIDs)

- Traditional disease-modifying anti-rheumatic drugs (DMARDs) must be withdrawn for at
least 4 weeks prior to baseline (methotrexate, sulfasalazine and hydroxychloroquine
or chloroquine may be allowed if at stable dose for at least 4 weeks prior to
baseline)

- Oral corticosteroids (≥ 10 mg/day prednisone or equivalent) and NSAIDs/COX-2
inhibitors must be at stable dose for at least 4 weeks prior to baseline

Exclusion Criteria:

- Major surgery (including joint surgery) within 8 weeks prior to screening or planned
major surgery within 6 months after randomization

- Total ankylosis of spine (as determined by investigator)

- Inflammatory rheumatic disease other than ankylosing spondylitis

- Active, acute uveitis at baseline

- Treatment with tumor necrosis factor (TNF) antagonist therapy at any time prior to
baseline

- Intra-articular or tendon injections or parenteral corticosteroids within 4 weeks
prior to screening

- History of severe allergic or anaphylactic reactions to humanized or murine
monoclonal antibodies

- Active current or history of recurrent bacterial, viral, fungal, mycobacterial or
other infection

- History of or currently active primary or secondary immunodeficiency

- Body weight > 150 kg