Background: Childhood-onset lupus nephritis (LN) is one of the most severe manifestations of systemic lupus erythematosus (SLE). Despite treatment-related toxicities, cyclophosphamide (CYC) and glucocorticoid-based treatment protocols are still considered standard therapy in managing this multisystem disorder. An effective and safe alternative induction regimen is needed.
Methods: Forty-four pediatric patients with active LN aged 3.5-13.8 (median 8.4) years, of whom 32 entered the study at diagnosis of SLE, were followed over 36 months. Induction therapy consisted of methylprednisolone pulses followed by either rituximab (RTX) (n = 17), mycophenolate mofetil (MMF) (n = 12) or pulse-CYC (n = 15), with tapering dose of prednisolone orally. MMF was added as maintenance immunosuppressant (800 mg/m2 daily) in all children from the third month onward.
Results: Flare-free survival was significantly higher at 36 months with RTX compared with MMF and CYC (100% for RTX vs. 83% for MMF. and 53% for CYC, p = 0·006). Twelve patients (76.5%) achieved complete remission with RTX compared with five (41.7%) and seven (46.7%) with MMF and CYC, respectively, at last follow-up. Requirement of mean daily dosage of prednisone was significantly lower in RTX group [p = 0.005 (RTX vs MMF); 0.0001 (RTX vs CYC) at 36 months] compared with other groups after the 3-month follow-up. In comparison with few minor adverse events in the other two cohorts, several serious adverse events occurred in the CYC group.
Conclusions: Efficacy and medium-term safety of RTX induction followed by MMF maintenance therapy in inducing and maintaining remission among children with LN were evident in this study.
Keywords: Cyclophosphamide; Lupus nephritis; Mycophenolate mofetil; Pediatric SLE; Rituximab.