Extracorporeal photopheresis (ECP) in refractory polyomavirus-associated nephropathy (PVAN)

Introduction: Extracorporeal photopheresis (ECP) is a little-invasive therapeutic intervention, particularly used in T-cell mediated diseases The mode of action primarily encompasses modulation of immunoregulatory processes In solid organ transplantation, treatment of refractory rejection by ECP has been reported;still the optimal indications for this treatment have yet to be determined We report our first experience with ECP in a case series of patients with high immunologic risk and refractory polyomavirus-associated nephropathy (PVAN) Methods: Three patients with refractory PVAN to center standard therapy with high immunological risk, where reduction in immunosuppression implied the risk of rejection, were planned to receive 8-10 sessions of ECP Results: One patient suffered acute rejection early after AB0-incompatible living donor kidney transplantation, and developed PVAN three months later Two patients displayed kidney allograft dysfunction due to PVAN after simultaneous pancreas and kidney transplantation (SPK) All patients were refractory to the PVAN standard center protocol (conversion to mTOR-based immunosuppression, cidofovir) Reduction in overall immunosuppression resulted in rising HbA1c in SPK patients After initiation of ECP, the first patient showed remission of PVAN with stabilization of allograft function One patient after SPK stabilized pancreas function but displayed progressive kidney allograft dysfunction after 8 sessions of ECP Yet the patient is still off dialysis 11 months after diagnosis of PVAN The other patient died in the early course due to severe COVID-19 infection, unrelated to ECP Conclusion: In conclusion, ECP, due to its immunomodulatory effects, might represent a novel therapeutic approach for selected patients with high immunologic risk allowing for reduction of maintenance immunosuppression Early intervention might be necessary and further data are highly warranted to identify the correct patient selection, treatment cycles and timing