BK virus kinetics and associated cystitis/urethritis symptoms after PTCy-based allogeneic hematopoietic cell transplant.

BK virus-associated cystitis/urethritis (BK-C) is a major cause of morbidity in allogeneic hematopoietic cell transplantation (HCT) recipients. We prospectively followed weekly plasma and urine BK viral loads and associated symptoms in 169 recipients of post-transplantation cyclophosphamide (PTCy)-based HCT. Patients with ≥2 positive BK specimens before day +100 were considered at-risk for developing BK-C.

Intermediate-dose posttransplantation cyclophosphamide for myeloablative HLA-haploidentical bone marrow transplantation.

High-dose posttransplantation cyclophosphamide (HD-PTCy), given at 50 mg/kg/day on days +3/+4, is a standard-of-care graft-versus-host disease (GVHD) prophylaxis for allogeneic hematopoietic cell transplantation (HCT). Our murine MHC-haploidentical HCT studies suggested intermediate-dose PTCy produces superior GVHD control compared with HD-PTCy and PTCy is maximally effective on day +4. We conducted a single-institutional prospective phase 1/2 trial to reduce PTCy dosing to 25 mg/kg/day on days +3/+4 or on day +4 only for myeloablative HLA-haploidentical bone marrow HCT using PTCy, sirolimus, and mycophenolate mofetil.

Safety but limited efficacy of donor lymphocyte infusion for post-transplantation cyclophosphamide-treated patients.

The therapeutic efficacy of donor lymphocyte infusions (DLIs) given after allogeneic hematopoietic cell transplantation (HCT) is limited by risk of graft-versus-host disease (GVHD). Post-transplantation cyclophosphamide (PTCy) effectively prevents severe GVHD, but there are limited data on outcomes of DLIs given to PTCy-treated patients. We reviewed 162 consecutive PTCy-treated patients transplanted between 2015-2022 within the Center for Immuno-Oncology at the National Cancer Institute.