Kidney involvement in systemic lupus erythematosus (SLE, lupus) is an important predictor of and contributor to morbidity and mortality from lupus. The approach to treatment for lupus nephritis is that of an induction phase of therapy (with cyclophosphamide vs mycophenolate mofetil) followed by long-term maintenance therapy. However, the optimal agent for chronic immunosuppression to prevent relapse or worsening of renal SLE is unknown.
Belimumab is a fully human IgG1λ antibody. It binds to the soluble cytokine, B-lymphocyte stimulator (BLyS) inhibiting its action. BLyS is important for the survival of B lymphocytes, but in patients with systemic lupus erythematosus (SLE) it is overexpressed.