THU0420 An extent of interstitial lung disease is a potential predictor of response to a-b-cell therapy in the patients with ssc
Authors: O. Koneva, O. Desinova, O. Ovasyannikova, L. Garzanova, M. Starovoytova, L. Ananieva
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Systemic sclerosis (SSc) is a connective tissue disease associated with chronic polyclonal B-lymphocytic activation and immunological tolerance disturbance. Several research and clinical studies showed that B-cell depletion is potentially efficacious in SSc treatment. However, neither strong evidence of RTX efficacy for treatment of interstitial lung disease (ILD) associated with SSc, no potential predictor of response to a-B-cell therapy. <h3>Objectives</h3> To evaluate rituximab (RTX) therapy efficacy in the patients with systemic scleroderma (SSc) differing in extent of interstitial lung disease (ILD) based on miltispiral computed tomography (MSCT) findings. <h3>Methods</h3> 42 patients (average age 48±2 years; male/female 1/6, diffuse/limited disease 1.5/1 (25 and 17), disease duration since the first non-Raynaud syndrome – 6.6±5.9 years) with definitely diagnosed SSc and ILD signs evidenced by MSCT were enrolled into the study. During the observation period 29±15.3 months the patients received rituximab (RTX) total dose of 2.5±1.3 grams in combination with glucocorticoids at average dose of 11.7±3.9 mg. 10 (24%) patients concurrently took immunosuppresants. The therapy efficacy was evaluated both in the general study population and in the patient subgroups with interstitial lesion extent up to 20% (Group A, n=13) and greater than 20% (Group B, n=29) of total pulmonary tissue area.<sup>1</sup> <h3>Results</h3> In the general patient population significant FVC increase from 73.2±18.8% to 82±21.8% (p=0.000031) and stabilisation of DLCO (42.6%±15.7% vs 44.7±14.6%. p=0.2) were observed. Median FVC increment was 6% (25th%&gt;3,3%; 75th%&gt;16%). FVC-based parameters increased by ≥10% in 16 (38%) patients and decreased in 3 (7%) patients. Average FVC values in Group A were significantly higher compared with Group B both at the baseline (88.8%±18.6% vs 65.4±14.5%, p=0.0002) and after the treatment (103.3%±15.9% vs 74.1±18.5%, p=0.0009) with statistically significant FVC increase in both groups during the treatment period (p=0.016 and p=0.0014, respectively). Median FVC increment in Group A and Group B was 10.2% (25th%&gt;4.7%; 75th%&gt;21.9%) and 5.9% (25th%&gt;2.75%; 75th%&gt;14.7%), p&gt;0.05, respectively. FVC-based parameters increased by ≥10% in 6 (46%) patients in Group A, and in 10 (34%) patients in Group B, and decreased in 1 (8%) and 2 (7%) patients, respectively. Average DLCO values were also significantly higher in Group A compared to Group B both before and after treatment (58.4%±16.4% vs 36.3±10.1%. p=0.025; 59.3±15.2% vs 38.9±9.7%. p=0.005); DLCO values did not change over time during RTX therapy. <h3>Conclusions</h3> RTX therapy resulted in significant FVC increase. FVC increment in the patient group with ILD extent up to 20% achieved clinical significance level in contrast to the patients with ILD extent greater than 20%, where FVC increment was 5.9%. Obtained data suggest that initial lung lesion area is a potential predictor of response to a-B-cell therapy in the patients with SSc. <h3>Reference</h3> [1] Moore O, Goh N, Corte T, et al. Extent of disease on high- resolution computed tomography lung is a predictor of decline and mortality in systemic sclerosis –related interstitial lung disease. Rheumatology. 2013; 52:155–160. doi:10.1093/rheumatology/kes289 <h3>Disclosure of Interest</h3> None declared