A Study of Secukinumab to Evaluate Maintenance of Response in Participants With Non-radiographic Axial Spondyloarthritis Who Achieved Remission

This study will establish whether prolonged chronic dosing with secukinumab is needed in participants with nr-axSpA who have achieved remission. Remission is defined as Ankylosing Spondylitis Disease Activity Score - C-reactive protein (ASDAS-CRP) Inactive Disease (ID) response Inactive Disease (ID) response (ASDAS-CRP < 1.3). The maintenance of remission on continued secukinumab treatment will be evaluated compared to placebo using a randomized withdrawal design. The primary outcome measure for this study is the proportion of participants remaining flare-free at Week 120.

Study treatment will be as follows:

• Open-label Secukinumab PFS (prefilled syringe) will be labeled as AIN457 150mg/1mL
• Double-blind Secukinumab and Placebo PFS will be labeled as AIN457 150mg/1mL/Placebo.

Study duration will be up to 128 weeks from Baseline.

The treatment duration will be up to 120 weeks with last treatment administration at Week 116.

In the Treatment Period 1 participant will attend a site visit approximately 1 month after Baseline and approximately every 12 weeks thereafter. In the Treatment Period 2 participant will attend site visits approximately every 4 weeks.

Inclusion criteria

• Male or non-pregnant, non-lactating female participants at least 18 years of age
• Clinical diagnosis of axSpA AND according to ASAS axSpA criteria:

• Inflammatory back pain for at least 6 months
• Onset before 45 years of age
• Sacroiliitis on MRI (magnetic resonance imaging) (as assessed by central reader) with ≥ 1 SpA feature OR HLA-B-27 positive with ≥2 SpA features
• Objective signs of inflammation at screening, evident by either MRI with Sacroiliac Joint inflammation (as assessed by central reader) AND / OR hsCRP > ULN (as defined by the central lab)
• Active axSpA as assessed by total BASDAI ≥ 4 cm (0-10 cm) at baseline.
• Spinal pain as measured by BASDAI question #2 ≥ 4 cm (0-10 cm) at baseline.
• Total back pain as measured by VAS (visual analog scale) ≥ 40 mm (0-100 mm) at baseline.
• Participants should have been on at least 2 different NSAIDs (non-steroidal anti-inflammatory drugs) at the highest recommended dose for at least 4 weeks in total prior to baseline with an inadequate response or failure to respond, or less if therapy had to be withdrawn due to intolerance, toxicity or contraindications.

Exclusion criteria

• Participants with radiographic evidence for sacroiliitis, grade ≥ 2 bilaterally or grade ≥ 3 unilaterally (radiological criterion according to the modified New York diagnostic criteria for AS) as assessed by central reader.
• Participants taking high potency opioid analgesics (e.g., methadone, hydromorphone, morphine).
• Previous exposure to secukinumab or any other biologic drug directly targeting IL-17 or IL-17 receptor or previous treatment with immunomodulatory biologic agents including those targeting TNFα (tumor necrosis factor α) (unless participants discontinued the treatment with TNFα inhibitor due to a reason other than efficacy [primary or secondary lack of efficacy, inadequate response] and only after appropriate wash-out period prior to baseline was observed).
• History of hypersensitivity to the study drug or its excipients or to drugs of similar chemical classes.
• Active ongoing inflammatory diseases other than nr-axSpA that might confound the evaluation of the benefit of secukinumab therapy, including uveitis.
• Active inflammatory bowel disease.
• History of ongoing, chronic or recurrent infectious disease or evidence of tuberculosis infection.