Real-world efficacy of belimumab in systemic lupus erythematosus: a prospective cohort from a single centre in China

Abstract Objective The objective of this study was to explore the efficacy and safety of belimumab among Chinese patients with SLE in a real-world setting. Methods A prospective cohort study was performed, and SLE patients taking belimumab on a background of standard-of-care (SoC) treatment were consecutively enrolled from July 2021 to December 2022. Based on baseline characteristics, the patients were divided into three groups: the newly diagnosed group, the relapsed group and the refractory group. Patients in the newly diagnosed group were newly diagnosed with SLE within 4 weeks of starting belimumab. Patients in the relapse group had experienced a severe flare. Refractory patients were patients with unsatisfactory GC taper and/or disease activity control. Clinical data were collected, and disease assessments were conducted regularly. Newly diagnosed patients with SoC alone and healthy controls (HCs) were also enrolled. Results A total of 123 SLE patients were included in the analysis, with a median follow-up period of 12 months (range 3–18 months). Thirty-three out of 123 patients were newly diagnosed, 32 had relapsed disease, and 58 had refractory disease. The SLE Responder Index 4 (SRI-4) response was achieved with good tolerance by 55.77% of patients at 3 months, 56.63% at 6 months, 63.24% at 9 months, 63.64% at 12 months and 57.14% at 18 months. Serological parameters (anti-dsDNA and C3/C4), SLEDAI-2K and daily prednisone intake were improved overall and in each group. Of the three groups, the newly diagnosed group had the highest SRI-4 rate as well as the greatest improvement in serological parameters and SLEDAI-2K. Compared with newly diagnosed patients with SoC alone, the cumulative prednisone intake of newly diagnosed patients taking belimumab was significantly decreased. Conclusion Our data supported the efficacy of belimumab in Chinese SLE patients in a real-life setting. Our study also provided new evidence indicating remarkable achievement of the SRI-4 response during belimumab therapy in newly diagnosed SLE patients.