Unrelated donor α/β T cell- and B cell-depleted HSCT for the treatment of pediatric acute leukemia.

TitleUnrelated donor α/β T cell- and B cell-depleted HSCT for the treatment of pediatric acute leukemia.
Publication TypeJournal Article
Year of Publication2022
AuthorsLeahy ABarz, Li Y, Talano J-A, Elgarten CW, Seif AE, Wang Y, Johnson B, Monos DS, Kadauke S, Olson TS, Freedman J, Wray L, Grupp SA, Bunin N
JournalBlood Adv
Volume6
Issue4
Pagination1175-1185
Date Published2022 Feb 22
ISSN2473-9537
KeywordsAcute Disease, Antigens, CD19, Child, Graft vs Host Disease, Hematopoietic Stem Cell Transplantation, Humans, Leukemia, Myeloid, Acute, Receptors, Antigen, T-Cell, alpha-beta, Recurrence, T-Lymphocytes, Unrelated Donors, Young Adult
Abstract

Unrelated donor (URD) hematopoietic stem cell transplant (HSCT) is associated with an increased risk of severe graft-versus-host disease (GVHD). TCRαβ/CD19 depletion may reduce this risk, whereas maintaining graft-versus-leukemia. Outcome data with TCRαβ/CD19 depletion generally describe haploidentical donors, with relatively few URDs. We hypothesized that TCRαβ/CD19-depletion would attenuate the risks of GVHD and relapse for URD HSCT. Sixty pediatric and young adult (YA) patients with hematologic malignancies who lacked a matched-related donor were enrolled at 2 large pediatric transplantation centers between October 2014 and September 2019. All patients with acute leukemia had minimal residual disease testing, and DP typing was available for 77%. All patients received myeloablative total body irradiation- or busulfan-based conditioning with no posttransplant immune suppression. Engraftment occurred in 98%. Four-year overall survival was 69% (95% confidence interval [CI], 52%-81%), and leukemia-free survival was 64% (95% CI, 48%-76%), with no difference between lymphoid and myeloid malignancies (P = .6297 and P = .5441, respectively). One patient (1.7%) experienced primary graft failure. Relapse occurred in 11 patients (3-year cumulative incidence, 21%; 95% CI, 11-34), and 8 patients (cumulative incidence, 15%; 95% CI, 6.7-26) experienced nonrelapse mortality. Grade III to IV acute GVHD was seen in 8 patients (13%), and 14 patients (26%) developed chronic GVHD, of which 6 (11%) had extensive disease. Nonpermissive DP mismatch was associated with higher likelihood of acute GVHD (odds ratio, 16.50; 95% CI, 1.67-163.42; P = .0166) but not with the development of chronic GVHD. URD TCRαβ/CD19-depleted peripheral HSCT is a safe and effective approach to transplantation for children/YAs with leukemia. This trial was registered at www.clinicaltrials.gov as #NCT02323867.

DOI10.1182/bloodadvances.2021005492
Alternate JournalBlood Adv
PubMed ID34872106
PubMed Central IDPMC8864664
Grant ListK12 CA076931 / CA / NCI NIH HHS / United States