PO:17:252 | The choice between belimumab and anifrolumab: analysis of a monocentric cohort

Fabio Congiu¹, Elisabetta Chessa², Giulia Rizzo¹, Elena Ragusa¹, Marta Paola Pireddu¹, Alessandra Oliva¹, Marianna Salis¹, Mattia Congia², Maria Maddalena Angioni¹, Micaela Rita Naitza¹, Alberto Floris², Alberto Cauli^1|2, Matteo Piga^1|2 | ¹AOU e Università degli studi di Cagliari; ²SC Reumatologia PO Duilio Casula, Cagliari, Italy

Background. Belimumab (BEL) and Anifrolumab (ANI) are currently the only biologic drugs authorized for the treatment of Systemic Lupus Erythematosus (SLE). The aim of the study is to analyze the factors associated with the therapeutic choice between BEL and ANI in a monocentric cohort of patients affected by SLE.

Materials and Methods. We conducted a prospective observational study on consecutively enrolled patients affected by SLE and treated with BEL or ANI starting from June 2022, the date when the compassionate use of ANI began. Clinical, clinimetric, serological, and therapeutic data (prednisone, previous and concomitant therapy) were collected. Univariate analysis was performed using the chi-square or Fisher’s test for categorical variables and the Mann-Whitney or Student’s t test for continuous variables; for multivariate analysis, logistic regression models were created selecting variables with p<0.05.

Results. The study included 22 patients treated with ANI (21 women, 95.5%) and 39 with BEL (35 women, 89.7%). The demographic, clinical, and therapeutic characteristics of the two groups at baseline are reported in the table, together with the results of the univariate analysis. In multivariate analysis, the use of ANI was preferentially associated with a chronic-active disease course (OR 17.8; 95% CI 3.5-91.7; p<0.001) and with active cutaneous manifestations (OR 9.9; 95% CI 1.5-66.5; p<0.017). In particular, the sub-analysis of cutaneous involvement showed an association between the preferential use of ANI compared with BEL in patients with subacute lupus (OR 12.7; 95% CI 2.0-79.4; p<0.006) and alopecia with lupus hair (OR 6.2; 95% CI 1.7-22.0; p<0.005). The use of BEL was significantly associated with a relapsing-remitting disease course (OR 10.7; 95% CI 2.3-50.1; p=0.002) and with the presence of active arthritis (OR 5.3; 95% CI 1.2-23.0; p<0.002). In particular, the sub-analysis of articular involvement showed a preferential association between the use of BEL and the subtype of non-deforming and non-erosive arthritis (OR 6.5; 95% CI 1.8-23.8; p<0.004). Although univariate analysis showed more active serology, with anti-DNA positivity (p=0.015) and complement consumption (p=0.061), in patients treated with BEL, these differences were not significant in multivariate analysis. No significant differences emerged between the two groups in terms of corticosteroid dose and concomitant use of hydroxychloroquine (HCQ). However, a greater number of patients treated with ANI were taking methotrexate, in relation to the predominant cutaneous involvement.

Conclusions. The choice of biologic drug in patients with active SLE currently appears to be mainly guided by the clinical phenotype, in line with evidence from registration trials. Real-life studies and the development of predictive biomarkers of response to specific biologic drugs will allow for better personalization of therapy within the framework of precision medicine.