Efficacy and safety of rituximab dosing for steroid-resistant idiopathic focal segmental glomerulosclerosis: a report of 12 cases

Objective To evaluate the efficacy and safety of rituximab (RTX) for steroid-resistant idiopathic focal segmental glomerulosclerosis (FSGS) in children.

Methods From 2014 to 2020, the relevant clinical data were retrospectively reviewed for 12 children of steroid-resistant idiopathic FSGS .

Results Steroid resistance was initial (n=10) and delayed (n=2). The age of initial RTX dosing was 8.00(5.15, 15.25) years. During a follow-up period of 6 months, complete remission (CR, n=3,) and partial remission (PR, n=1) were obtained. At the last follow-up, there were CR (n=1) and PR (n=2). Remission rate was higher in children on ≥3 doses than in those on <3 doses (6-month follow-ups: 66.7% vs 25.0%; last follow-up: 66.7% vs 12.5%). Remission rate was higher in children with delayed steroid resistance than in those with initial steroid resistance (6-month follow-ups: 100.0% vs 20.0%; last follow-up: 100.0% vs 10.0%). Remission rate was higher in children with a non-nephrotic range of urinary protein than in those with a nephrotic range of urinary protein (6-month follow-ups: 50.0% vs 16.7%; last follow-up: 33.3% vs 16.7%). During treatment and follow-ups, there were infusion reaction (n=1) and severe pneumonia (n=3).

Conclusion RTX is efficacious for primary steroid-resistant FSGS in select children. However, it responds poorly to primary steroid-resistant FSGS or a nephrotic range of urinary protein. A greater number of doses may stabilize clinical response rates. Close follow-ups are required after RTX dosing for preventing infection.