SAT0274 THE EFFECT OF RITUXIMAB ON LUNG FUNCTION AND SKIN SCORE IN SYSTEMIC SCLEROSIS-ASSOCIATED INTERSTITIAL LUNG DISEASE. LONG-TERM OBSERVATION
Authors: Liudmila Garzanova, Lidia P. Ananyeva, Olga Koneva, Oxana Desinova, Olga Ovsyannikova, Mayya Starovoytova, Alexander Volkov, Svetlana Glukhova
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> There is a large clinical experience about the efficiency of rituximab (RTX) for the treatment of systemic sclerosis (SSc). There are several studies showing the decrease in skin induration and interstitial fibrosis in the lungs as the effect of therapy. However, there are not many long-term observations. <h3>Objectives:</h3> To describe the efficacy of RTX on lung function and skin score in patients with systemic sclerosis-associated interstitial lung disease, in long-term follow-up. <h3>Methods:</h3> This study included 71 patients (pts) with SSc. Data were collected prospectively. The mean follow-up period was 42 mo (12-72). Mean age was 46 years (17-66), female-59 (83%), diffuse cutaneous subset of the disease had 42 (59%), Scl-70 positivity-73% of pts. Duration of the disease was 5,6±4,4 yrs. All pts received concomitant treatment with low dose prednisolone and 45% - with immunosupressants. The following indicators were evaluated: forced vital capacity,% predicted (FVC), diffusing capacity for carbon monoxide,% predicted (DLCO) and Rodnan skin score (mRss) over a periods of 12-18 months (point 1), 24-30 months (point 2), 36-42 months (point 3), 48-54 months (point 4) and 60-72 months (point 5) after the start of therapy. The results are presented in the form of mean values, delta, median, upper and lower quartile. <h3>Results:</h3> In point 1 (n=71) the cumulative mean dose of RTX was 1,43±0,6 gr. The mRss decreased from 11,3±9,6 to 8±6,6 (p = 0,000007). FVC increased from 77,4±19,9 to 82,6±20,7% (p=0.0001). DLCO remained stable (from 47,0±18,5 to 47,23±16,7%). In point 2 (n=55) the cumulative mean dose of RTX was 2,97±0,8 gr. ΔmRss – 5,4 (median 3; 25th% 0; 75th% 10). ΔFVC – 7,5% (median 8,2; 25th% -1,1; 75th% 14,4). ΔDLCO – 0,21% (median -0,2; 25th% -6,2; 75th% 6,6). In point 3 (n=36) the cumulative mean dose of RTX was 3,45±1,3 gr. ΔmRss – 5,1 (median 3,5; 25th% 0; 75th% 9). ΔFVC – 9,3% (median 7,7; 25th% 1,45; 75th% 15,3). ΔDLCO – 3,4% (median 3,6; 25th% 2,45; 75th% 7,76), p=0,02. In point 4 (n=24) the cumulative mean dose of RTX was 3,96±1,1 gr. ΔmRss – 5,3 (median 3; 25th% 0; 75th% 10). ΔFVC – 12,2% (median 7,9; 25th% 1,1; 75th% 24,2). ΔDLCO – 3,9% (median 0,45; 25th% -0,95; 75th% 6,8). In point 5 (n=17) the cumulative mean dose of RTX was 5,15±1,7 gr. It should be noted that this group included patients with initially the lowest DLCO (below 40%). ΔmRss – 7,3 (median 5; 25th% 1; 75th% 14). ΔFVC – 13,2% (median 11; 25th% 8,7; 75th% 23,4). ΔDLCO – 5,9% (median 1,6; 25th% -4,8; 75th% 13,8). <h3>Conclusion:</h3> The results of this study confirm the data on the positive effect of RTX in patients with SSc (decrease of skin induration, increase of FVC, stabilization of DLCO). The decrease of skin score is accompanied by the improvement of lung function indicators. In our study, there was a significant increase of DLCO associated with long-term treatment (over 36 mo) and a cumulative dose of RTX over 3,45±1,3 gr. Patients with initially lower DLCO can achieve a significant improvement by the 60th month of RTX therapy. Our work shows that patients with SSc-associated interstitial lung disease are required long-term treatment with RTX (at least 3-5 years) to achieve an obvious improvement of the lung function. <h3>Reference</h3> [1] Jordan S, Distler JH, Maurer B, Huscher D, van Laar JM, Allanore Y. et al; EUSTAR Rituximab study group. Effects and safety of rituximab in systemic sclerosis: an analysis from the European Scleroderma Trial and Research (EUSTAR) group. Ann Rheum Dis 2015;74(6):1188–94. <h3>Disclosure of Interests:</h3> None declared