Rituximab for multirelapsing, steroid-dependent or steroid-resistant, minimal-change nephropathy – a report of nine adult cases

Minimal-change nephropathy (MCN) accounts for 10-15% of cases of the nephrotic syndrome in adults. Frequent relapses occur in 10-25% of cases and steroid dependence is seen in 25-30%. Rituximab is a chimeric mono-clonal antibody directed against CD20-positive B-cells with reported benefit in immune-mediated renal disease. We present six female and three male patients, ranging from 27-70 years of age, with multirelapsing, steroid-dependant or steroid-resistant MCN, with previous multiple courses of cortico-steroids (CS) and second-line therapies. Five patients were steroid dependant with the lowest daily CS dose between 5-20 mg/day. All patients were given two doses of rituximab, each a flat dose of 500 mg except for one case who received a dose of 1000 mg. All patients were B-cell depleted before the second dose. No major side effects occurred. Seven of the patients responded to therapy with normalized plasma albumin and no albuminuria enabling discontinuation or tapering of CS significantly below levels where relapses had occurred in the past (P=0.03). One patient reached partial remission and another had no response to therapy. Follow-up was 6-33 months. There were three relapses after 9, 12, and 20 months, respectively. In conclusion, frequency of relapses and steroid dependency or resistance in MCN remain therapeutic challenges to physicians. The current case series suggests that B-cell depletion may induce long-lasting remissions and, as a result, has a potential as a steroid-sparing agent in the treatment of steroid-dependent and multirelapsing MCN patients.