AB0964 EFFICACY AND DRUG SURVIVAL OF IXEKIZUMAB IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS FROM THE CZECH BIOLOGICS REGISTRY ATTRA: IMPACT OF PRIOR SECUKINUMAB EXPOSURE
Authors: L. Šenolt, K. Pavelka, K. Kusalová, J. Baranová, P. Horak, L. Procházková, S. Forejtova, H. Mann, K. Bubova, J. Vencovský, J. Zavada
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Ixekizumab (IXE) and secukinumab (SECU), both interleukin-17A inhibitors (IL-17i), are available for the treatment of active axial spondyloarthritis (axSpA). IL-17i are commonly used following the failure of tumour necrosis factor inhibitors (TNFi) or as the first line biologic. However, limited evidence exists on the efficacy of IXE in axSpA patients previously exposed to SECU. <h3>Objectives:</h3> This study aims to stratify axSpA patients initiating IXE based on prior exposure to SECU or TNFi. The objective was to compare baseline demographic and clinical disease characteristics, treatment response and drug survival. <h3>Methods:</h3> Patients with axSpA who experienced treatment failure with SECU or TNFi and promptly initiated IXE as their subsequent biologic therapy between Jan 2021 and Oct 2023 were enrolled from the Czech Republic biologics registry ATTRA. Disease activity was evaluated using the Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ASDAS-CRP), and the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), along with CRP at baseline, 3 and 6 months. Comparisons of disease activity scores between SECU-exposed and TNFi-exposed patients were analysed using the Mann-Whitney test. Drug survival was analysed using the Kaplan–Meier method and Cox proportional-hazards model. <h3>Results:</h3> Among the 5,435 patients treated for axSpA, 101 initiated IXE, with 73 switching directly from prior treatment with TNFi (n=45) or SECU (n=28). A few more patients were female (57.5%) and HLA-B27 positivity was observed in 83.6% The median age of patients was 48 (32; 69) years (median (5.; 95. percentile)), and the duration of the disease from diagnosis was 9 (2; 26) years. At baseline, axSpA patients with previous SECU exposure, in comparison to those with TNFi exposure, were more likely to receive IXE as a 3rd or 4th line (75.0% vs. 44.4%) and exhibited significantly higher BASDAI (5.8 (2.3; 9.3) vs. 5.0 (0.9; 8.8); p=0.043), but not ASDAS (3.5 (2.1; 5.2) vs. 3.2 (1.4; 4.8); p=0.117) or CRP levels (12.9 (2.2; 41.5) vs. 7.6 (1.0; 46.3) mg/l; p=0.242). In axSpA patients with prior exposure to both TNFi as well as to SECU, substantial reductions in BASDAI and ASDAS were demonstrated at 3 and 6 months (Figure 1A). Probably due to higher previous biologic drug use at baseline, patients with prior SECU exposure exhibited lower rates of ASDAS remission or low disease activity at 3 and 6 months compared to those with prior TNFi exposure (37.6% and 33.3% vs. 50.0% and 45.5%). Overall 12-month drug survival on IXE was 86.3% (72.9; 100.0) for axSpA patients with prior exposure to SECU and 79.7% (67.2; 94.6) for those with prior exposure to TNFi (Figure 1B). <h3>Conclusion:</h3> IXE demonstrates effectiveness and favourable drug survival in axSpA patients, even among those with prior exposure to SECU, despite a history of multiple biologic treatments. However, a larger patient cohort is required to confirm these findings. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Ladislav Šenolt AbbVie, Bristol-Myers Squibb, Celltrion, Eli Lilly, Merck Sharp and Dohme, Novartis, Pfizer, Sanofi-Aventis, Sobi, UCB, Karel Pavelka: None declared, Kateřina Kusalová: None declared, Jana Baranová: None declared, Pavel Horak: None declared, Leona Procházková: None declared, Sarka Forejtova: None declared, Heřman Mann: None declared, Kristyna Bubova: None declared, Jiří Vencovský: None declared, Jakub Zavada: None declared.