Efficacy of CD19-guided B-cell depletion with rituximab plus steroids in refractory focal segmental glomerulosclerosis
摘要
Refractory focal segmental glomerulosclerosis (FSGS) poses significant therapeutic challenges under conventional immunosuppressants. Although rituximab (RTX), an anti-CD20 monoclonal antibody, has demonstrated efficacy in nephrotic syndrome, its real-world effectiveness in adults with refractory FSGS remains unproven.
Study designWe retrospectively included 34 adults with biopsy-proven FSGS that was refractory to immunosuppressive regimens involving corticosteroids or calcineurin inhibitors, defined by persistent proteinuria > 3.5 g/day with < 50% reduction from baseline despite at least 4 months of therapy. Patients were grouped into either RTX combined with prednisone (RTX group, n = 16) or conventional non-RTX regimens (including prednisone, calcineurin inhibitors, cyclophosphamide, or their combinations; Conv group, n = 18). Rituximab was dosed to achieve peripheral B-cell depletion (CD19⁺ cell = 0/µL). Endpoints comprised complete remission (CR), overall response, relapse in initial responders, and relapse-free survival.
ResultsThe patients were 44.4 ± 21.8 years old, with a median follow-up duration of 18.0 (10.6, 41.1) months. The baseline characteristics were comparable between groups, except that RTX group had a longer disease duration than Conv group (median 10.7 vs. 4.0 months, p = 0.046). The CR rate was 62.5% in RTX group and 33.3% in Conv group (p = 0.168), while the overall response rate was 75.0% in RTX group and 50.0% in Conv-group (p = 0.172). Among the responders, the median follow-up was 33.6 months in the Conv group and 36.1 months in the RTX group (p = 0.557). Responders in RTX group had a lower relapse rate compared to those in Conv group (25.0% vs. 77.8%, p = 0.030), and had a prolonged relapse-free survival (log-rank χ²=3.827, p = 0.050). There were 3 patients in RTX group relapsed, who achieved CR after repeat RTX therapy. No severe infusion reactions or opportunistic infections were observed in RTX group.
ConclusionsRTX combining with prednisone was comparable in inducing remission for refractory FSGS patients and was associated with a significantly lower relapse rate and a strong trend towards prolonged relapse-free survival than conventional therapy. While heterogeneity exists, RTX may be a valuable therapeutic strategy for maintaining long-term disease control in responsive patients.
Clinical trail numberNot applicable.