New transplant approach aims to fight blood cancers with fewer side effects

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: Recipient: * Age less than or equal to 21 years * High risk hematologic malignancy whereas allogeneic transplantation is the current standard of care. This includes (but is not limited to): * High risk ALL in CR1 or CR2, * any ALL in CR3 or subsequent; * AML in high risk CR1 (AML diagnosis includes myeloid sarcoma), * any AML in CR2 or subsequent, * any therapy related AML; * MDS (primary or secondary), * NK cell, biphenotypic, or undifferentiated leukemia/lymphoma in CR1 or subsequent; * CML in accelerated phase, or in chronic phase with persistent molecular positivity or intolerance to tyrosine kinase inhibitor, or a history of blast crisis. * If prior CNS leukemia, it must be treated and in CNS CR * Left ventricular ejection fraction \> 40%, or shortening fraction ≥ 25% * Creatinine clearance (CrCl) or glomerular filtration rate (GFR) ≥ 50 ml/min/1.73m2 * Forced vital capacity (FVC) ≥ 50% of predicted value; or pulse oximetry ≥ 92% on room air if patient is unable to perform pulmonary function testing * Karnofsky or Lansky (age dependent) performance score ≥ 50 (See APPENDIX A) * Bilirubin ≤ 3 times the upper limit of normal for age * Alanine aminotransferase (ALT) or Aspartate aminotransferase (AST) ≤ 5 times the upper limit of normal for age Donor: * At least single haplotype matched (≥ 4 of 8) family member * At least 18 years of age * HIV negative * Regarding donation eligibility, is identified as either: * Completed the process of donor eligibility determination as outlined in 21 CFR 1271 and agency guidance; OR * Does not meet 21 CFR 1271 eligibility requirements, but has a declaration of urgent medical need completed by the principal investigator or physician sub-investigator per 21 CFR 1271 Exclusion Criteria: Recipient: * Has a suitable HLA-identical sibling or suitable 12/12 (HLA-A, B, C, DRB1, DQB1, and DPB1) HLA-matched unrelated donor available in an appropriate time frame. * Any other active malignancy other than the one for which this HCT is indicated * Received a prior allogeneic HCT at any time * Received an autologous HCT within the previous 6 months * Pregnant, if female is of childbearing potential, negative test must be confirmed by serum or urine pregnancy test within 14 days prior to enrollment * Breast feeding * Any current uncontrolled bacterial, fungal or viral infection Donor: * Pregnant, negative test must be confirmed by serum or urine pregnancy test within 14 days prior to enrollment if female * If female, breast feeding