OP0126 LONG-TERM FOLLOW UP OF ABATACEPT IN USUAL INTERSTITIAL PNEUMONIA ASSOCIATED TO RHEUMATOID ARTHRITIS. NATIONAL MULTICENTER STUDY OF 172 PATIENTS

Abstract

Background: Interstitial lung disease (ILD) is a severe extra-articular manifestation of rheumatoid arthritis (RA). Usual interstitial pneumonia (UIP) is the most frequent, and severe ILD pattern in RA. Abatacept (ABA) has demonstrated effectiveness in RA-ILD during a 12-month period of treatment 1-2]. Objective(s): To assess the effectiveness and safety of ABA in RA-ILD patients with radiological pattern of UIP during a long-term follow-up. Method(s): From a large observational multicenter study of 392 RA-ILD patients treated with ABA, we selected those with UIP. We analyzed from baseline the following outcomes: a) forced vital capacity (FVC), b) diffusing capacity of the lungs for carbon monoxide (DLCO), c) chest high resolution computed tomography (HRCT), d) dyspnea (modified Medical Research Council scale) and e) arthritis activity (DAS28-ESR). Result(s): We included a total of 172 patients with UIP (91 women/81 men; mean age 66.9+/-10.1 years). Baseline demographic and clinical characteristics are shown in Table 1. The median ILD duration up to ABA initiation was relatively short, with a median of 11 3-39] months. Mean baseline values of FVC and DLCO were >80% and >60%, respectively. During the follow-up, median of 24 10-44] months, 70.2% and 66.9% of patients showed an improvement/ stabilization of FVC and DLCO, respectively. Evolution of these parameters along 48 months is displayed in Figure 1. Available chest HRCT images improved/ stabilized in 64.5% of patients. Stabilization or improvement of dyspnea was found in 78.6% of patients. The majority of patients showed articular remission or low activity (mean DAS28-ESR of 4.3+/-1.5 at baseline and 2.5+/-1.5 at 48 months). ABA was withdrawn in 39 (22.6%) patients due to ILD worsening (17), articular inefficacy (9), serious infections (7) and other causes (n=6, development of malignancy in 3, diagnosis of giant cell arteritis and change to tocilizumab in 1, and 2 deceases). Conclusion(s): ABA shows a lasting effectiveness and safety in RA-ILD patients with UIP, the most aggressive pattern.