#1514 Rituximab in minimal change disease: reducing hospitalizations and steroid use

Abstract Background and Aims Minimal Change Disease (MCD) generally has a favorable renal prognosis; however, the standard high-dose glucocorticoid treatment can be associated with substantial side effects, adversely impacting patients' quality of life. In conditions such as ANCA-associated vasculitis and lupus nephritis, lower doses of steroids have demonstrated comparable clinical outcomes with fewer side effects. The anti-CD20 monoclonal antibody Rituximab may reduce steroid dependence and improve outcomes in MCD, but long-term data on its efficacy, safety, sustained remission, or potential for cure remain scarce. Method This retrospective study included patients with biopsy-confirmed MCD diagnosed via electron microscopy. The study period spanned from disease onset to June 2024. Patients received Rituximab according to protocol (1 g intravenously on days 0 and 14, equivalent to one cycle). Initial steroid therapy included intravenous methylprednisolone (250 mg every 24 hours for three consecutive days), followed by oral prednisone (30 mg daily, tapered by 5 mg every 15 days). "Cure" was defined as complete remission without any medication for MCD for more than 5 years. Results Thirteen consecutive patients (mean age 51 years, SD 18; 46% male) were included. The mean time from diagnosis to study inclusion was 198 months (min:18, max:608), and the mean follow-up period after the first Rituximab dose was 78 months (min:17, max:137). Seven patients (54%) were classified as corticosteroid-resistant or corticosteroid-dependent. Among the six corticosteroid-dependent patients, only one required maintenance therapy with 5 mg/day of prednisone, prescribed for general well-being rather than due to persistent proteinuria. The baseline estimated glomerular filtration rate (eGFR; CKD-EPI) at Rituximab administration was 100 mL/min/1.73 m² (95% CI: 90–109). The median number of Rituximab doses was 3 (IQR: 2–6), with 6 patients (46%) requiring only one cycle. At the end of follow-up, eGFR remained stable (mean change: −2.8 mL/min/1.73 m², 95% CI: −9.6 to 3.9; P = 0.37). Complete remission was achieved in 77% of patients (10 patients) after the first Rituximab cycle, with all eventually reaching remission. Proteinuria resolved within 6 months post-Rituximab (median: 0 mg/g; IQR: 0–0.4; P = 0.001). Median annual steroid doses significantly decreased from 2130 mg (IQR: 1211–9870) to 157 mg (IQR: 0–1224; P = 0.001). Four patients (31%) met the criteria for cure. The percentage of patients requiring hospitalization decreased from 69% to 8% (P = 0.008). Two mild infusion reactions occurred, and one moderate reaction was attributed to anti-Rituximab antibodies. No patients required dialysis. At the time of follow-up, 5 patients (39%) temporarily received additional immunosuppressants (4 tacrolimus and 1 mycophenolate mofetil) for disease control. Conclusion Rituximab demonstrates high efficacy in the management of minimal change disease (MCD), with 46% of patients requiring only a single treatment cycle and 31% achieving long-term remission, fulfilling criteria for a “cure.” The therapy substantially reduced the need for corticosteroids, thereby minimizing associated risks and significantly lowered hospitalization rates. Rituximab was well-tolerated, with only minor infusion-related adverse events reported. These findings underscore Rituximab as a promising and effective alternative to glucocorticoids in the treatment of MCD.