AB0485 DOES THE REASON OF DISCONTINUATION OF THE FIRST TNF INHIBITOR INFLUENCE THE RESPONSE TO THE SECOND TNF INHIBITOR IN SPONDYLOARTHRITIS? PILOT STUDY FROM THE MOROCCAN RBSMR REGISTRY
Authors: T. Fatima Zahrae, T. Latifa, H. Rkain, I. Hmamouchi, L. Achemlal, I. El Bouchti, A. Elmaghraoui, I. Ghozlani, H. Hassikou, T. Harzy, L. Ichchou, O. Mkinsi, R. Niamane, R. Bahiri, F. Allali
Journal: Annals of the Rheumatic Diseases (2021)

Background: In rheumatoid arthritis, studies have shown that the response to a second TNF inhibitor is better if the first TNF inhibitor was stopped for a secondary failure or adverse event compared to a primary failure [1,2]. However, few studies have provided evidence regarding the response to a second TNF inhibitor based on the reason for discontinuation of the first TNF inhibitor in patients with a diagnostic of spondyloarthritis (SpA). Objectives: To evaluate the efficacy of the 2nd TNF inhibitor in real life from a cohort of patients with SpA from the Moroccan registry of biological therapies in rheumatic diseases (RBSMR Registry), according to the reason for discontinuation of the 1st TNF inhibitor. Methods: We have included from the RBSMR Registry any patient with a diagnosis of SpA starting a 2nd TNF inhibitor on inclusion in the registry or during the 1st year of follow-up. A descriptive study was conducted by measuring the therapeutic maintenance of the 2nd TNF inhibitor as well as the disease activity in different groups of patients according to the reason for stopping the first TNF inhibitor: stopping for ineffectiveness, side effect or non-availability of the drug. Results: Of the total 194 patients with SpA included in the RBSMR registry, 40 patients were on their 2nd TNF inhibitor at one year follow-up. The mean age of the patients was 43.6 ± 15.1 with a male predominance (57.5%) and a mean of disease duration of 13.75±6.95 years. At 1 year, treatment was maintained in 72.5% of all patients: 100% after ineffectiveness, 82% after discontinuation for side effects and 52.9% for unavailability of the first TNF inhibitor. Moderate disease activity as defined by an Ankylosing Spondylitis Disease Activity Score using ASDAS-CRP &lt;2.1 was achieved at 1 year in 75%, 64.7% and 52.9% respectively in patients who stopped their first TNF inhibitor for side effects, ineffectiveness or unavailability of treatment. Conclusion: This pilot study gives us a small insight into the fate and efficacy of the 2nd TNF inhibitor based on the reason for discontinuation of the first. The follow-up data at 2 and 3 years will allow us to include more patients and thus be able to do a real statistical study with a comparison between the different groups. References: [1]Remy A, Avouac J, Gossec L, Combe B. Clinical relevance of switching to a second tumour necrosis factor-α inhibitor after discontinuation of a first tumour necrosis factor-α inhibitor in rheumatoid arthritis: a systematic literature review and meta-analysis. Clin Exp Rheumatol. 2011;29:96–103. [2]Chatzidionysiou K, Askling J, Eriksson J, Kristensen LE, van Vollenhoven R, ARTIS group. Effectiveness of TNF inhibitor switch in RA: results from the national Swedish register. Ann Rheum Dis. 2015;74:890–6. Disclosure of Interests: None declared.