THU0337 COMPARISON OF THE EFFICACY OF TWO RITUXIMAB REGIMENS IN THE PATIENTS WITH SYSTEMIC SCLEROSIS ASSOCIATED WITH INTERSTITIAL LUNG DISEASE

Abstract

Background: Rituximab (RTM) is considered as a promising therapeutic agent for treatment of insterstitial lung disease (ILD) in the patients with systemic sclerosis (SSc). However, the limited number of RTM-treated patients, heterogeneity of the studies in relation to main parameters, considerably different dose regimens, cumulative doses, and observation periods does not allow univocal conclusions on RTM efficacy or definitive recommendations on RTM use in the patients with SSc. The question whether to combine RTM with immunosupressants (IS) or it is possible to use it as a single-agent therapy in the patients with SSc associated with ILD is still relevant. Objectives: To compare the time courses of pulmonary function parameters and dermal fibrosis parameters during the use of RTM in combination with IS and as a single-agent therapy in the patients with SSc associated with ILD in the open-label prospective non-randomized study. Methods: 90 patients with the confirmed SSc diagnosis and ILD evidence based on HRCT findings were enrolled into the study. All patients received low-dose and moderate-dose prednisolone regimens. Group A (n=45) received a total RTM dose 3.1±1.2 g in combination with IS (27/60% mycophenolate mofetyl, 16/35.6% cyclophosphamide, 2/4.4% methotrexate; the patient’s average age was 47.4±11.6 years, with female proportion 82%; SSc duration 4.6±3.5 years; diffused/localized forms 1.3/1). Group B (n=45) received RTM as a single therapy agent in a total dose 2.7±1 g (average age 45.0±15 years, female proportion 82%, SSc duration 6.7±5.6 years, diffused/localized forms 1.5/1). The age, gender proportion, SSc form, FVC and DLCO, and RTM cumulative doses were similar in the both groups. The follow-up period was 42 months. The time courses of FVC, DLCO, modified skin count (mRss, points), activity index (EScSG, points) were assessed in the study. Results: In Groups A and B during the therapy significant decrease in mRss (p=0.00034 and 0.000002 respectively) and EScSG (p=0.00011 and 0.000000 respectively), FVC increase (p;=0.00017 and 0.00001, respectively), and stabilization of the DLCO were observed. The treatment groups did not differ significantly in the median FVC increment, clinically meaningful FVC and DLCO increments of decrements, and EScSG and mRss time courses. Notes:in Parameters column 1 = before treatment, 2 = after treatment; M ± SD = mean value and standard deviation; * = significant difference between the vales measured before and after the treatment Conclusion: RTM administration both in combination with IS and as a single agent therapy in the patients with SSc associated with ILD effectively alleviated skin induration and EScSG, improved or stabilized the pulmonary function parameters. The absence of statistically significant difference in the time course of evaluated parameters between the groups substantiate potential RTM use as a single-agent therapy that, this is most important for the patients with poor tolerability or contraindications to IS administration. Disclosure of Interests: None declared