AB0409 B CELLS PROFILE AS A BIOMARKER FOR EARLY IDENTIFICATION OF OPTIMAL RESPONDERS TO TNF INHIBITORS IN RHEUMATOID ARTHRITIS
Authors: Cristina Sobrino, Borja Hernández-Breijo, Carlota García-Hoz, Israel Nieto-Gañán, Victoria Navarro-Compán, Ana Martínez-Feito, Javier Bachiller-Corral, Gemma Bonilla, Paloma Lapuente-Suanzes, Cristina Pijoan Moratalla, Dora Pascual-Salcedo, Alejandro Balsa, Garbiñe Roy, Mónica Vázquez, Luisa María Villar, Chamaida Plasencia, Eulalia Rodríguez-Martín
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> The most common biological agents used as disease-modifying treatment in rheumatoid arthritis (RA) are TNF inhibitors (TNFi). Although these new strategies to treat RA have improved the course of the disease, approximately 30-50% of patients do not respond to this therapy. Early identification of optimal responders is crucial in the clinical setting. <h3>Objectives:</h3> The aim of this study was to investigate if baseline percentages of different leukocyte subsets in peripheral blood (PBMCs) can contribute to identify RA patients who will respond to TNFi. <h3>Methods:</h3> This was a prospective bi-center pilot study including 100 RA patients under TNFi therapy. Clinical activity was assessed at baseline and 6 months of treatment by disease activity score 28 (DAS28), considering optimal responders if they reached remission at 6 months (DAS28≤2.6). PBMCs were obtained before treatment and different leukocyte subsets were evaluated by flow cytometry (FACSCantoII instrument). The association between the percentage of PBMCs at baseline and clinical response at 6 months was evaluated through logistic regression models (odds ratio; 95% CI). All the analyses were adjusted by sex, age, disease duration, concomitant methotrexate, baseline DAS28 and seropositivity (ACPA and/or RF). <h3>Results:</h3> Demographic characteristics are shown in Table 1. After 6m of TNFi treatment, 40% of the patients achieved clinical remission. A significant association between higher percentage of total B cells (OR=1.19; 95%; CI:1.05-1.35; p=0.007) and naive B cells (Bn; OR=1,32; 95%; IC:1.08-1.61; p=0.007) at baseline and clinical response was found. The other PBMC subsets (monocytes, NK cells, CD4+ and CD8+ T cells subtypes) did not show statistical differences (Figure 1). <h3>Conclusion:</h3> Our results suggest that basal B cells profile may contribute to identify optimal responders to TNFi in RA. (Funding: ISCIII (PI16/01092, PI16/00474). <h3>Disclosure of Interests:</h3> Cristina Sobrino: None declared, Borja Hernández-Breijo: None declared, Carlota García-Hoz: None declared, Israel Nieto-Gañán: None declared, Victoria Navarro-Compán: None declared, ANA MARTÍNEZ-FEITO: None declared, Javier Bachiller-Corral: None declared, Gemma Bonilla: None declared, Paloma Lapuente-Suanzes: None declared, Cristina Pijoan Moratalla: None declared, DORA PASCUAL-SALCEDO Grant/research support from: Pfizer, Speakers bureau: Pfizer, Abbvie, Takeda, Alejandro Balsa Grant/research support from: Abbvie, Pfizer, Novartis, BMS, Nordic, Sanofi, Consultant for: Abbvie, Pfizer, Novartis, BMS, Nordic, Sanofi, Sandoz, Lilly, Paid instructor for: Pfizer, Speakers bureau: Pfizer, Novartis, UCB, Nordic, Sanofi, Sandoz, Lilly, Garbiñe Roy: None declared, Mónica Vázquez: None declared, Luisa María Villar: None declared, Chamaida Plasencia Speakers bureau: Pfizer, MSD, Eulalia Rodríguez-Martín: None declared