Position Statement of the Immunonephrology Working Group of the Portuguese Society of Nephrology on the Use of Belimumab in Lupus Nephritis

Systemic lupus erythematosus (SLE) is a challenging immune ‑mediated disease that frequently involves the kidney as lupus nephritis (LN), an immune complex glomerulonephritis. Its occurrence is associated with increased morbidity and mortality and current treatment still fails to preserve renal function in the long term. As such, more efficacious and less toxic treatments are needed to treat LN, aiming to reduce renal relapses and improve renal survival. Belimumab, an inhibitor of the soluble B ‑cell activating factor became the first biologic agent approved for the treatment of SLE and is now approved as an add ‑on therapy for LN. Herein, the Immunonephrology Working Group of the Portuguese Society of Nephrology reviewed the scientific evidence that led to belimumab´s approval in recent LN guidelines and exposed its perspective on the use of belimumab in LN in Portugal.