Rituximab in Steroid-Dependent Podocytopathies

Area of Science:

• Nephrology
• Immunology
• Pharmacology

Background:

• Primary podocytopathies, including minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS), often require long-term immunosuppression due to steroid dependence and frequent relapses.
• Rituximab (RTX), an anti-CD20 monoclonal antibody, has emerged as a potential treatment alternative for these challenging conditions.
• However, optimal RTX dosing regimens and the long-term efficacy of repeated RTX administration remain subjects of ongoing investigation.

Purpose of the Study:

• To evaluate the efficacy and safety of induction and maintenance rituximab (RTX) therapy in adult patients with primary podocytopathies.
• To assess RTX's impact on remission rates, relapse frequency, and the need for concomitant immunosuppressive medications.
• To analyze the outcomes of RTX treatment in patients with steroid-dependent minimal change disease and focal segmental glomerulosclerosis.

Main Methods:

• A retrospective case series design was employed, analyzing adult patients with steroid-dependent podocytopathies who received RTX induction therapy.
• Data collected included remission and relapse rates, use of corticosteroids and other immunosuppressants, B-cell depletion status, and adverse events.
• Maintenance RTX therapy was administered at the discretion of the treating physician.

Main Results:

• Fourteen patients (7 with MCD, 7 with FSGS) were included. Most received RTX induction (2 x 1000 mg or 4 x 375 mg/m²).
• At a mean follow-up of 47.3 months, 10 patients achieved complete remission, and 2 achieved partial remission.
• Significant reductions were observed in relapse rates, corticosteroid/immunosuppressant use, and prednisolone dosage compared to baseline. Maintenance RTX in 6 patients led to sustained remission. Four patients experienced infusion reactions.

Conclusions:

• Rituximab (RTX) therapy supports achieving steroid-free remission in patients with primary podocytopathies.
• Maintenance RTX appears to be well-tolerated and is associated with sustained remission.
• Further research is warranted to establish optimal RTX induction and maintenance regimens for steroid-dependent podocytopathies.