AB0416 SUBCUTANEUS VS INTRAVENOUS ABATACEPT IN RHEUMATOID ARTHRITIS-INTERSTITIAL LUNG DISEASE. NATIONAL MULTICENTER STUDY OF 392 PATIENTS

Background Interstitial lung disease (ILD) is a severe extra-articular manifestation of rheumatoid arthritis (RA). Abatacept (ABA) has demonstrated efficacy in RA-ILD [1-2]. Clinical trials have shown equivalence subcutaneous (SC) and intravenous (IV) administration ABA for articular manifestations [3]. However, it not been studied RA-ILD. Objectives to compare the effectiveness patients according route (IV-ABA vs SC-ABA). Methods National multicenter study on treatment with ABA. They were divided into 2 groups administration: a) IV, b) SC. We analyzed from baseline following outcomes both groups: ) forced vital capacity (FVC), b diffusing lungs carbon monoxide (DLCO), c chest high resolution computed tomography (HRCT), d dyspnea (assessed modified Medical Research Council scale), e activity DAS28-ESR or described clinical records), f sparing corticosteroids effect. Results total 392 [SC-ABA/IV-AB; 288/91(available data)] patients. Baseline demographic characteristics are Table 1 . Patients followed-up median [IQR] 24 [10-48] months. FVC DLCO remain stable during first months SC-ABA IV-ABA [Figure 1]. Dyspnea stabilized improved 85% (89% IV-ABA; 83% was withdrawn 80 patients: 60 (39%) group 20 (22%) group. ILD worsening inefficacy most common reasons discontinuation. Conclusion In RA-ILD, seems equally effective safe regardless IV References [1] Rheumatology (Oxford). 2020 Dec 1;59(12):3906-3916. [2] 2021 24;61(1):299-308. [3] Arthritis Rheum. 2011 Oct;63(10):2854-64. 1. Main general features at All (n=392) (n=91) SC (n=288) p Age, years mean±SD 65 ± 10 66 0.85 Women n (%) 226 (58) 54 (59) 166 0.77 Smoker ever 210 (54) 49 154 (53) 0.95 duration up ABA, months, 11 (3-38) (2-48) (3-36) 0.65 RF 347 (89) 78 (86) 256 0.41 ACPA 344 76 (85) (90) 0.25 4.35±1.58 4.19±1.52 4.38±1.53 0.35 pattern NIU 172 (44) 47 (52) 122 (42) NINE 117 (30) (22) 94 (33) 0.14 Other 98 (25) 23 (26) 72 (% predicted) 87 21 82 22 88 0.26 67 19 0.97 Prednisone baseline, mg/day, 5 (5-10) 7.5 0.34 ACPA, anti-citrullinated protein antibodies; DLCO, monoxide; FVC, capacity; RF, factor; UIP, usual interstitial pneumonia. Figure Evolution pulmonary function tests (mean % predicted DLCO) therapy Members Spanish Collaborative Group Luis Arboleya-Rodríguez, Javier Narváez, Juan Carlos Fernández, Belén Miguel, Iván Cabezas, Andrea García Valle, Clara Aguilera Cros, S. Romero-Yuste, Ignacio Villa Blanco, Sabela Fernández Aguado, Raquel Almodóvar, C. Ojeda-García, Aguilera-Cros, B. García-Magallón, Antonio Mas, M. J. Moreno-Ramos, A. Ruibal-Escribano, Rosa Expósito, José Bernal, Evelin Cervantes, Rodríguez-García, R. Castellanos-Moreira, Castellví, Manuel Rodríguez, Eva Salgado, Enrique Raya, Pilar Morales, Lorena Mª Noelia Álvarez, Andreu, E. F. Vicente-Rabaneda, López-Robles, López-Corbeto, Hidalgo-Calleja, J.C. Fernández-López, Alejandro Olivé, Rodríguez-Muguruza, Iñigo Hernández, N. Quillis-Marti, J.A. Bernal-Vidal, García-Aparicio, Castro-Oreiro, Fernández-Melón, P. Vela Casasempere, María Fito, Rodríguez-Gómez, D. Palma-Sánchez, L. Expósito-Pérez, Andreu. Acknowledgements: NIL. Disclosure Interests Ana Serrano-Combarro: None declared, Atienza-Mateo: Del-Val: Libe Ibarrola Paino: Ivette Casafont-Solé: Rafael Melero: Alba Pérez Linaza: Isabel Serrano-García: Santos Castañeda: Rafaela Ortega Castro: Jerusalem Calvo Gutierrez: Natalia Mena-Vázquez: Nuria Vegas-Revenga: Lucía Domínguez Casas: Delgado-Beltran: Carolina Díez: Trinidad Sandoval: Retuerto-Guerrero: Albaladejo: López-Sánchez: Guadalupe Mazano: Anahy Brandy-Garcia: Patricia López Viejo: Gemma Bonilla: Olga Maiz: Maria del Carmen Carrasco Cubero: Marta Garijo Bufort: Mireia Moreno: ANA URRUTICOECHEA-ARANA: Sergi Ordoñez: González-Montagut Gómez: Peralta-Ginés: Ramón De Dios Jiménez de Aberásturi: Camila Osorio: Elena Cañadillas: Fernando Lozano Morillo: Tomas Vazquez Rodriguez: Carreira: J M Blanco: Fernández-Díaz: Loricera: Ferraz-Amaro: Diego Ferrer: Ricardo Blanco Speakers bureau: Abbvie, Pfizer, Roche, lilly, Bristol-Myers, Janssen, Galapagos MSD, Consultant of: Janssen Grant/research support from: novartis Roche.