Efficacy and NSAID-sparing effect of secukinumab 150 mg in ankylosing spondylitis: results from phase IV ASTRUM study

Background: Radiographic axial spondyloarthritis (r-axSpA), formerly known as ankylosing spondylitis (AS), is a chronic, inflammatory rheumatic disease associated with symptoms such as inflammatory back pain, morning stiffness, and arthritis. First-line recommendations for patients with AS include treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) for reducing pain and stiffness. Objectives: The objective of our study is to evaluate the efficacy and short-term NSAID-sparing effect of secukinumab in patients with AS currently treated with NSAIDs. Design: We assessed the clinical Assessment of SpondyloArthritis International Society (ASAS20) response to secukinumab and evaluated the extent to which the use of concomitant NSAID can be reduced between weeks 4 and 12 in r-axSpA patients treated with secukinumab 150 mg compared with placebo. Methods: ASTRUM was a prospective 24-week randomized controlled trial of adult patients with active r-axSpA [Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ⩾4] who had a documented inadequate response to ⩾2 NSAIDs. Patients were randomized (1:1:1) to initiate treatment with subcutaneous secukinumab 150 mg from either week 0 (group 1), week 4 (group 2), or week 16 (group 3). From week 4 onward, tapering of NSAIDs was allowed in all groups. Results: This study included 211 patients (n = 71, 70, and 70 in groups 1, 2, and 3, respectively). ASAS20 response at week 12 for pooled groups 1 and 2 versus group 3 was 51.1% versus 44.3% (p = 0.35). A higher proportion of patients in groups 1 and 2 achieved ASAS40 and BASDAI50 and showed improvements in other secondary clinical outcomes as compared to group 3 at week 16. More patients in groups 1 and 2 versus group 3 stopped their NSAID intake from baseline through week 16. Conclusion: Treatment with secukinumab improved clinical outcomes and showed a short-term NSAID-sparing effect in patients with r-axSpA, even though the primary endpoint was not met. Trial registration: ClinicalTrials.gov; NCT02763046, EudraCT 2015-004575-74.