Which are the clinical characteristics that lead to the decision of primary or secondary usage of TNFi or IL-17i in patients with axial spondyloarthritis?: Real-world evidence from the RABBIT-SpA cohort.

OBJECTIVES

Assessment of Spondyloarthritis International Society (ASAS)-EULAR treatment recommendations for axial spondyloarthritis (axSpA) suggest advanced therapies after failure of nonsteroidal anti-inflammatory drugs. However, there is insufficient evidence about the best treatment sequence. The primary objective of this study was to analyse the choice of first-/second-line biological disease-modifying antirheumatic drug (bDMARD) treatment as prescribed in routine rheumatology care and to compare patient and disease characteristics at the beginning of first/second bDMARD.

METHODS

bDMARD-naïve patients from the prospective German RABBIT-SpA registry initiating their first tumour necrosis factor inhibitor (TNFi) or interleukin-17i (IL-17i) were eligible. Characteristics at beginning of first-/second-line therapy were compared between the 2 groups.

RESULTS

First line: 848 of 1006 patients were treated with TNFi; 158 with IL-17i. Significant differences were found in regard to extramusculoskeletal manifestations (EMMs): psoriasis/uveitis/inflammatory bowel disease (IBD) in 14%/10%/none of IL-17i compared with 7%/14%/5% of TNFi patients. Disease activity, joint count (JC), and patient-reported outcomes were not statistically significant different. Second line: in 289 patients (of those 248 with TNFi, 41 with IL-17i first line), second-line data were available. Of the 248 TNFi first-line patients, 179 (76%) cycled to a second TNFi, whereas 58 (25%) switched to IL-17i. Switchers had significantly higher JC and enthesitis counts. Axial Spondyloarthritis Disease Activity Score did not differ. Significant differences were again found in EMMs: psoriasis/uveitis/IBD in 16%/7%/5% of IL-17i compared with 9%/13%/9% of TNFi patients. Cycler experienced more often secondary failure, switcher more often primary failure in their first-line TNFi.

CONCLUSIONS

As recommended in ASAS-EULAR recommendations, EMMs in particular are taken into account in routine care for the treatment decision in first-/second-line bDMARD.