Third-party BK virus-specific cytotoxic T lymphocyte therapy for hemorrhagic cystitis following allotransplantation

BK virus-associated hemorrhagic cystitis (BKV-HC) is a common complication after allogenic hematopoietic stem cell transplantation. A prospective study at MD Anderson Cancer Center (Houston, TX) evaluated third-party BK virus-specific cytotoxic T lymphocytes (CTLs), generated from healthy donors and banked for off-the-shelf use, for the management of BKV-HC after alloHCT. Infusion of CTLs resulted in overall response in 40 of 59 evaluable patients (67.7%) at 14 days and in 40 of 49 evaluable patients (81.6%) at 45 days. Responses were durable; no patient lost a previously achieved response. There were no cases of de novo grade 3 or 4 GVHD, graft failure, or infusion-related toxicities. The authors conclude that off-the-shelf BKV-CTLs are a safe and effective therapy for BKV-HC after alloHCT.