Efficacy of rituximab on disease activity, severity, and disease-related damage in patients with immunosuppressive-resistant systemic sclerosis.

Background/aim: B-cell depletion with rituximab (RTX) is widely used as a rescue therapy in patients with systemic sclerosis (SSc). The aim herein was to analyze the progress of disease-related outcomes after RTX therapy in severe SSc patients. Materials and methods: Included in this study were 27 SSc patients who were followed-up between 2012 and 2020 and received at least 1 cycle of RTX for active disease, despite receiving standard immunosuppressives (ISs). In addition to the European Scleroderma Study Group and European Scleroderma Trials and Research Group activity scores, Medsger's severity, and the recently developed Scleroderma Clinical Trials Consortium Damage Index values were evaluated initially and at 1 year after the first infusion. The progress of individual organ damage was also assessed at the end of the follow-up period (at least 6 months after the last infusion) using the data extracted from the medical records. Results: Disease activity and severity-improved and disease-related overall damage worsened after the first year of RTX therapy (p < 0.001, p = 0.008, and p = 0.005). Some of the disease-related organ damage had improved at the end of the follow-up period, indicating its reversibility. Overall damage scores ≥11 after the first year of RTX therapy were found to be associated with mortality (p = 0.035). Conclusion: RTX contributed to reducing the activity and severity in SSc patients with severe disease, nonetheless the efficacy related to the damage was limited. High damage scores in the first year were found to be associated with mortality. Spontaneous progress of manifestations requiring a longer period to improve and irregular consecutive RTX courses might lead to difficulties in differentiation between activity and damage.