Rituximab as add-on therapy in patients with resistant lupus nephritis who have failed induction or maintenance therapy with other agents: A real-world experience from a single center in Mumbai

Background Lupus nephritis (LN) is associated with poor outcomes and a significant risk of progression to end-stage renal disease (ESRD). Some patients with resistant LN do not respond adequately to current treatment options and need alternative strategies or therapies. Objective The objective is to evaluate the efficacy and safety of rituximab as a re-induction therapy (Re-RTX) followed by maintenance therapy for patients with resistant LN. Methods Twenty-four patients with resistant LN (failed initial induction therapy or severe relapse after remission) were analyzed. Re-RTX was co-administered with other immunosuppressants. The primary KDIGO criteria outcomes included renal response (complete and partial), disease progression, relapses, and infections. Results The median age was 28 years (IQR 24.5–42), and the female-to-male ratio was 11:1. All patients had active LN, and 91.3% had proliferative LN. Baseline creatinine was 1.075 mg% (IQR 0.7–1.38), and mean urine protein-to-creatinine ratio (UPCR) was 4.9 (IQR 2.8–6.65). Of the patients receiving RTX as re-induction therapy, 66.6% (16/24) had failed initial induction therapy with other immunosuppressants, whereas 33.3% (8/24) had severe relapse during maintenance therapy. Re-RTX had a favorable renal response at 6 months, with 91.7% of the patients responding (20.8% complete response and 70.8% partial response). At 12 months, 58.3% of the patients maintained a renal response (25% complete response and 33.3% partial response). Approximately one-third of patients relapsed within a year. Fourteen patients (58.3%) continued RTX maintenance therapy with two different treatment regimens. At 6 months, Regimen-1 (500 mg every 6 months) resulted in a partial response in 43% (3/7) and relapse in 57% (4/7) of patients. Regimen 2 (1 g dose per year) achieved a complete response in 28.5% (2/7) and a partial response in 71.5% (5/7) with no relapses at 6 months. At a median follow-up of 29 months, adverse renal outcomes were observed in 29.16% of the patients with progression to advanced chronic kidney disease (CKD) or end-stage renal disease (ESRD). The overall use of Re-RTX was considered safe, with a reported infection prevalence of 16%, which is comparable to the existing data. Conclusion Re-RTX demonstrated efficacy and safety as an induction therapy for resistant LN. However, the response waned after 1 year, underscoring the need for optimized maintenance therapy.