A Pilot Study on the Efficacy and Safety of Rituximab in the Maintenance of Remission in Adults with Minimal Change Disease

Background: Minimal change disease (MCD) is a common etiology of nephrotic syndrome (NS). Steroid therapy is usually effective, but frequent relapses / steroid-dependent are therapeutic challenges. Rituximab ( RTX ) has shown promising results in inducing remission of relapsed and refractory MCD in adults, reducing the recurrence rate of the disease and prolonging the recurrence-free time. However, the efficacy and safety of RTX in maintaining the remission of adult-onset MCD have not been reported. Methods: 12 patients were confirmed by renal biopsy as MCD and received intravenous methylprednisolone (500mg/d, for 3 days) followed by oral methylprednisolone(0.8mg / kg / day). All patients achieved complete remission(CR) within 8 weeks，and then were randomised 1:1 to receive methylprednisolone(n=6) and RTX (n=6, 375mg/m2, intravenous, once weekly, 2 times in total). The methylprednisolone maintenance remission group(MMRG) continued oral methylprednisolone alone, with a reduction of 4 mg every 2-4 weeks. In the RTX maintenance remission group(RMRG), the methylprednisolone was reduced from the 9th week to discontinuation. The total exposure time of methylprednisolone was no more than 9 weeks. Results: All patients presented with NS with a median urine protein quantification of 10.89 g/24h (5.9, 13.8 g/24h) and a median serum albumin level of 16.7 g/l (13.43, 19.85g/l). Their renal function was normal when MCD was diagnosed. Of the 6 patients with MCD in MMRG, there were three patients of relapsed during glucocorticoid reduction, 1 patient relapsed 1 month after glucocorticoid withdrawal, and 2 patients relapsed 2 months after glucocorticoid withdrawal. The Median duration of sustained remission was 7 months (4.75, 8 months, inter quartile range (IQR)). 6 patients in RMRG during a follow-up of 18.5 months (17, 20.5 months) had no relapse. Compared with the MMRG, the RMRG had significantly longer recurrence-free time (P＜0.001) and less glucocorticoid exposure(P＜0.001). No adverse events occurred in all patients. Conclusion: RTX maybe an effective and safe treatment option for adult patients with first-episode MCD in maintaining disease remission and minimizing glucocorticoid exposure. However, high-quality clinical studies are needed to confirm the efficacy of rituximab in the maintenance of remission in first-episode MCD. Funding: Government Support – Non-U.S.