Effectiveness of secukinumab in radiographic and non-radiographic axial spondyloarthritis: a European routine-care observational study

Abstract

Objectives To compare the treatment effectiveness of secukinumab in radiographic (r) versus non-radiographic (nr) axial spondyloarthritis (axSpA) patients treated in routine care across Europe. Methods Prospectively collected data on secukinumab-treated axSpA patients with known radiographic status were pooled from nine countries. Remission rates based on patient-reported outcomes (PROs; Numeric Rating Scale (0–10), for example, pain ≤2/Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≤2 and Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease (ID) <1.3 after 6/12/24 months of secukinumab treatment were calculated. Remission and drug retention rates in r-axSpA versus nr-axSpA patients were compared by logistic and Cox regression models (unadjusted/adjusted for age+sex/adjusted for multiple confounders). Results Overall, 1161 secukinumab-treated patients were included (r-axSpA/nr-axSpA: 922/239). At baseline, r-axSpA patients had longer disease duration and higher C reactive protein, were more often male and HLA-B27 positive and had received fewer prior biological or targeted synthetic disease-modifying antirheumatic drugs compared with nr-axSpA patients, whereas PROs were largely similar. During follow-up, crude PRO remission rates were significantly higher in r-axSpA compared with nr-axSpA patients (6 months: pain≤2: 40%/28%, OR=1.7; BASDAI≤2: 37%/25%, OR=1.8), as were drug retention rates (24 months: 66%/58%, HR 0.73 (ref: r-axSpA)). Proportions of patients achieving ASDAS ID were low for both groups, particularly nr-axSpA (6 months: 11%/8%). However, when adjusting for age+sex, these differences diminished, and after adjusting for multiple confounders, no significant between-group differences remained for either remission or drug retention rates. Conclusion Crude remission/drug retention rates in European secukinumab-treated patients were higher in r-axSpA compared with nr-axSpA patients. In adjusted analyses, secukinumab effectiveness was similar in both groups, suggesting that observed differences were related to factors other than radiographic status.