Iptacopan treatment for recurrent dense deposit disease after kidney transplant: A case report.

C3 glomerulopathies, including dense deposit disease, are rare kidney disorders caused by dysregulation of the alternative complement pathway. Recurrence after kidney transplantation is common and can threaten graft survival. Iptacopan, an oral factor B inhibitor, was recently Food and Drug Administration-approved as the first targeted therapy for C3 glomerulopathies. We describe a 19-year-old woman with childhood-onset dense deposit disease who progressed to kidney failure and underwent deceased donor transplantation. Post-transplant, she experienced delayed graft function and persistently low serum C3. A biopsy on day 7 revealed C3-only deposits, indicating early recurrent disease. Iptacopan was initiated at 200 mg twice daily. Her serum C3 normalized within 1 week and remained stable over 6 months. Proteinuria decreased significantly, and renal function improved and stabilized. This case highlights the potential of iptacopan as a disease-specific therapy for post-transplant C3 glomerulopathies recurrence, reinforcing its clinical utility and mirroring outcomes from the APPEAR-C3G trial.