Pulsipher MA, Ahn KW, Bunin NJ, et al. KIR-Favorable TCR-αß/CD19-Depleted Haploidentical HCT in Children with ALL/AML/MDS: Primary Analysis of PTCTC ONC1401. Blood. 2022; (doi: 10.1182/blood.2022015959).
TCR-αß/CD19-depleted haploidentical donors with reduced toxicity conditioning (RTC) for children with acute leukemia and myelodysplastic syndrome (MDS) demonstrated improved outcomes, according to new research. The prospective multicenter study, conducted by the Pediatric Transplantation and Cellular Therapy Consortium, included 51 patients aged 0.7-21 years with acute lymphocytic leukemia, acute myeloid leukemia, or MDS. Donors were killer immunoglobulin-like receptor (KIR)-favorable based upon ligand mismatch and/or high B-content. Disease-free survival (DFS) at one year was 78%. Patients <10 years of age, those treated with RTC instead of standard myeloablative conditioning, and those with flow minimal residual disease (MRD) <0.01% pre-transplant had superior two-year DFS and overall survival (OS). Based on multivariate analysis comparing the KIR-favorable haploidentical cohort with concomitantly enrolled Center for International Blood and Marrow Transplant Research controls, DFS and OS were comparable to other donor sources. There was a lower risk of acute graft-versus-host-disease (GVHD), chronic GVHD, and transplant-related mortality among the KIR-favorable group compared with the other donor cell sources. Of interest, 53% of enrolled patients were ethnic and racial minorities. Data from a large cohort of recipients/donors screened for KIR showed that >80% of recipients had a KIR-favorable donor by our definition. Researchers concluded that this approach may be broadly applicable to groups often unable to find donors.
Tags: MRD, patient care, GVHD, children, pediatric, Cellular therapy, Survival, myeloblative, leukemia, Research, Transplant, improvement, CD19, bone marrow, lymphoblastic leukemia, acute myeloid leukemia