Pos0194 Factors Associated With Radiographic Spinal Progression in Patients With Axial Spondyloarthritis Receiving Il-17a Inhibitor or TNF Inhibitor Therapy: A Post-Hoc Analysis of the Surpass Study

Background: Previous studies have identified several predictors of radiographic spinal progression in patients with axial spondyloarthritis (axSpA), including pre-existing structural damage (syndesmophytes) and inflammatory activity.1 Most of these studies were conducted in patients not receiving biological disease-modifying anti-rheumatic drugs (bDMARDs) or were focusing on only one drug class. Therefore, it is uncertain whether the factors associated with the progression of structural damage are the same for patients receiving bDMARDs with different modes of action. Objectives: The aim of this post-hoc analysis was to evaluate the relationship between baseline factors and radiographic spinal progression over 2 years in the SURPASS study (NCT03259074) in patients with radiographic (r-) axSpA treated with secukinumab (SEC, an interleukin IL-17A inhibitor) or adalimumab biosimilar (SDZ-ADL, a tumour necrosis factor TNF inhibitor). Methods: SURPASS was a phase IIIb randomised controlled study in biologic-naïve patients with active r-axSpA at high risk for radiographic spinal progression (high-sensitivity C-reactive protein hsCRP ≥5 mg/L and/or ≥1 syndesmophyte(s) on spinal radiographs). Patients were randomised (1:1:1) to receive SEC (150 or 300 mg; dose-blinded) or SDZ-ADL (40 mg; open label) for 2 years (104 weeks). The dataset considered for this post-hoc analysis included all patients with data available for radiographs and magnetic resonance imaging (MRI) of spine at baseline and week 104. Radiographic spinal progression was assessed by the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) by 3 blinded readers. A patient was considered to have a syndesmophyte if at least 2 of the 3 readers assessed mSASSS score of ≥2 for any individual vertebral corner. The proportion of patients that developed new syndesmophytes (according to majority agreement - 2 of the 3 readers) was calculated. Spinal inflammation and fat lesions as assessed by MRI were evaluated by three blinded readers. Factors associated with new syndesmophyte formation (yes/no) at week 104 were analysed using univariable logistic regression analysis. A multivariable logistic regression analysis was also conducted, incorporating sex, current smoking, presence of syndesmophytes, elevated hsCRP, non-steroidal anti-inflammatory drug score, total spine oedema score and fatty lesion score as baseline covariates, with selection of these variables informed by both univariable analyses and clinical expertise. Results: A total of 288 patients (n=99 on SEC 150 mg, n=95 on SEC 300 mg, and n=94 on SDZ-ADL) were included in the analysis based on the availability of complete sets of radiographs and MRIs. Demographic and baseline disease characteristics are provided in Table 1. At week 104, new syndesmophytes were observed in 18.2%, 15.8%, and 14.9% of the patients receiving SEC 150 mg, SEC 300 mg, and SDZ-ADL, respectively. In the univariable analysis, the presence of syndesmophytes and higher level of inflammatory activity as reflected by elevated CRP, higher Axial Spondyloarthritis Disease Activity Score, and higher spinal MRI bone marrow oedema score at baseline were associated with the development of new syndesmophytes over 2 years (Table 2). There were no relevant differences between the treatment arms regarding the factors associated with new syndesmophyte formation. The multivariable analysis confirmed the association of baseline structural damage in the spine and inflammatory activity in predicting syndesmophyte formation after 2 years (Table 2). Conclusion: Pre-existing structural damage and high inflammatory activity at baseline were associated with new syndesmophyte development in r-axSpA patients irrespective of treatment with IL-17 or TNF inhibitors over 2 years. REFERENCES: 1 Poddubnyy D, and Sieper J. Curr Rheumatol Rep. 2017;19(9):55. Acknowledgements: NIL. Disclosure of Interests: Denis Poddubnyy Speaker fees from AbbVie, BMS, Lilly, MSD, Novartis, Pfizer, UCB, Consultation fees from AbbVie, Biocad, BMS, Eli Lilly, Gilead, MSD, Novartis, Pfizer, Samsung Bioepis, UCB, Research grant from AbbVie, Eli Lilly, MSD, Novartis, Pfizer, Juergen Braun Received speakers bureau fees from Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, Medac, MSD (Schering-Plough), Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis, UCB pharma and Eli Lilly, Consultant for Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis and UCB, Eli Lilly, Grant/research support from Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis and UCB, Eli Lilly, Pedro Machado Abbvie, BMS, Celgene, Eli Lilly, Galapagos, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB, Consulting/speaker's fees from Abbvie, BMS, Celgene, Eli Lilly, Galapagos, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB, Victoria Navarro-Compán Abbvie, BMS, Eli Lilly, Fresenius Kabi, Galapagos, Janssen, MoonLake, MSD, Novartis, Pfizer, Roche and UCB, Consulting/speaker's fees from Abbvie, BMS, Eli Lilly, Fresenius Kabi, Galapagos, Janssen, MoonLake, MSD, Novartis, Pfizer, Roche and UCB, Lianne S Gensler Consulting fees from AbbVie, Acelyrin, Eli Lilly, Fresenius Kabi, Janssen, MoonLake, Novartis, Pfizer and UCB, Grant/research support from Novartis, UCB, and Pfizer, Kay-Geert Hermann Lecture fees from MSD, Novartis, Pfizer, Consulting fees from AbbVie, Erhard Quebe-Fehling Owns Novartis stocks, Employee of Novartis Pharma AG, Basel, Switzerland, Christelle C. Pieterse Employee of Syneos Health contracting for Novartis, Aimee Readie Owns Novartis stocks, Employee of Novartis Pharmaceuticals Corporation, Corine Gaillez Own Novartis stock, Employee of Novartis Pharma AG, Xenofon Baraliakos Speakers' bureau AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB, Consultant for AbbVie, BMS, Celgene, Chugai, Galapagos, Merck, Novartis, Pfizer, UCB, Grant/research support from AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB.