OP0081 COMPARISON OF CYCLE VERSUS SWAP TREATMENT STRATEGY ON DRUG RETENTION AND DISEASE ACTIVITY AFTER TNFi FAILURE IN AXIAL SPONDYLOARTHRITIS: A QUASI-EXPERIMENTAL STUDY
Authors: I. Van Es, J. E. Vriezekolk, N. Den Broeder, L. De Beijer, A. A. Den Broeder, N. Van Herwaarden, E. A. M. Mahler, E. F. A. Leijten
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Patients with axial spondyloarthritis (axSpA) who initiate a biological disease-modifying antirheumatic drugs (bDMARD) often experience loss of effectiveness or side effects. The EULAR treatment guidelines then recommend to start another bDMARD, but without preference for cycling within the same bDMARD class or swapping to another mode of action. In the Sint Maartenskliniek (SMK), the Netherlands, the local drug formulary recommended a cycle strategy (TNFi →TNFi) prior to 2019 and a swap strategy (TNFi →IL-17i) after 2019. This resulted in a quasi-experimental study cohort, that allowed us to compare the cycle versus swap strategy. <h3>Objectives:</h3> (1) to compare the 3-year drug retention rate and 1-year disease activity of a second TNFi (cycle) versus an IL-17i (swap) strategy and (2) to identify patient and disease characteristics associated with the efficacy of cycling versus swapping, in patients with axSpA who failed a first TNFi. <h3>Methods:</h3> All patients with a clinical diagnosis of axSpA who were prescribed a second TNFi or IL-17i were included from the Integral Rheumatology Information System (IRIS) of the SMK. Patients were grouped as either a cycler or a swapper. Drug retention was based on treatment failure (event) defined as discontinuation due to inefficacy or side effects. Drug retention was analyzed using Kaplan-Meier curve, log-rank test and multivariable cox regression, adjusted for the potential confounding disease and patient characteristics. The mean difference in disease activity (BASDAI) between baseline, 6 months and 12 months was compared between cyclers and swappers using student's t-test. <h3>Results:</h3> In total, 335 axSpA patients who have visited the SMK between 2012 and 2023 were included. Of them, 270 were cycler and 65 swapper, with similar baseline patient and disease characteristics (Table 1). Overall, 45.2% and 14.4% of the cyclers and 47.7% and 15.4% of the swappers discontinued their second-line bDMARD therapy respectively due to inefficacy and side-effects. At 12 and 24 months, drug retention rates were 80.7% and 64.4% respectively for cyclers, and 64.6% and 55.4% for swappers. Swappers were more likely to experience treatment failure (HR adjusted for sex and discontinuation reason first TNFi: 1.47 (95% CI: 1.04 – 2.09), p = 0.03) (Figure 1). In women and in patients who experienced inefficacy of their first TNFi, swapping resulted in a significant higher risk of treatment failure (HR for women, adjusted for discontinuation reason first TNFi: 1.60 (95% CI: 1.00 – 2.56), p = 0.05 and HR for those with inefficacy of first TNFi, adjusted for sex: 1.76 (95% CI: 1.17 – 2.64), p &lt; 0.01). At 6 months, the mean BASDAI score was 4.48 (sd: 2.10) for cyclers and 4.06 (sd: 2.36) for swappers and at 12 months, this was 4.29 (sd: 2.12) and 3.87 (sd: 2.31) for cyclers and swappers respectively. There were no significant differences in mean difference in BASDAI between cyclers and swappers at any timepoint. <h3>Conclusion:</h3> After failure to a first TNFi in patients with axSpA, the drug retention rate was higher in the cycle strategy compared to the swap (IL-17i) strategy. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Ilse van Es: None declared, Johanna E. Vriezekolk Received grants from Novartis and Eli Lilly, unrelated to work presented in the current abstract, Nathan den Broeder: None declared, Lisan de Beijer: None declared, A.A. den Broeder Received grants for research and quality of care projects to the institution from Lilly, Abbvie, Galapagos, Novartis, Pfizer, Gilead, Sanofi, Biogen and Celltrion, Noortje van Herwaarden: None declared, E.A.M. Mahler Received grants for research and quality of care projects to the institution from Abbvie, Eli Lilly, Pfizer, Novartis, unrelated to work presented in the current abstract, Emmerik F.A. Leijten Received funding for research grants from Novartis and Eli Lilly, unrelated to work presented in the current abstract.