BACKGROUND: As a result of the COVID-19 widespread pandemic, cryopreservation of allogeneic donor apheresis products was implemented to mitigate the challenges of donor availability and product transport. Although logistically beneficial, the impact of cryopreservation on clinical outcomes and graft composition remains unclear.OBJECTIVES: To compare the outcomes and graft composition with cryopreserved versus fresh allografts in the setting of allogeneic hematopoietic cell transplantation (allo-HCT).STUDY DESIGN: We retrospectively analyzed the clinical outcomes of 30 consecutive patients who received cryopreserved allografts between March and August 2020 as compared to 60 consecutive patients who received fresh allografts prior to the COVID-19 pandemic. Primary endpoints were hematopoietic engraftment, graft failure (GF) and secondary outcomes were overall survival (OS), relapse free survival (RFS) and non-relapse mortality (NRM). In addition, extended immunophenotype analysis was performed on cryopreserved versus prospectively collected fresh apheresis samples.RESULTS: Compared to fresh allografts, both neutrophil and platelet recovery were delayed in recipients of cryopreserved reduced intensity conditioning (RIC) allo-HCT with median times to engraftment of 24 days vs 18 days (P?=?.01) and 27 days vs 18 days (P?=?.069), respectively. We observed primary GF in 4 of 30 patients in the cryopreserved cohort (13.3%) vs only one of 60 patients (1.7 %) in the fresh cohort (P?=?.03). Cryopreserved RIC allo-HCT was associated with significantly lower median total, myeloid and T-cell donor chimerism at 1 month. OS and RFS were inferior for cryograft recipients with hazard ratio [HR (95%Cl)]: 2.16 (1.00, 4.67) and 1.90 (0.95, 3.79), respectively. Using an extended immunophenotype analysis we compared 14 samples from the cryopreserved cohort to 6 prospectively collected fresh apheresis donor samples. These analyses showed both decrease in total cell viability and significantly reduced absolute numbers of NK cells (CD3-CD56+) in the cryopreserved apheresis samples.CONCLUSION: In this single institution study we note delayed engraftment and a trend toward clinical inferiority of cryopreserved vs fresh allografts. Further evaluation of the use of cryopreserved allografts and their impact on clinical and laboratory outcomes is warranted.
View details for DOI 10.1016/j.jtct.2022.01.010
View details for PubMedID 35042013