Treosulfan-Based Versus Clofarabine-Based Conditioning Before Donor Hematopoietic Stem Cell Transplant for the Treatment of Myelodysplastic Syndromes or Acute Myeloid Leukemia

OUTLINE: Patients are randomized to 1 of 2 arms. ARM A: Patients receive treosulfan intravenously (IV) over 2 hours on days -6 to -4 and fludarabine IV over 30 minutes on days -6 to -2. Patients also undergo total-body irradiation (TBI) followed by HCT on day 0. Patients undergo echocardiography (ECHO) or multigated acquisition scan (MUGA) and lumbar puncture pre-transplant and undergo bone marrow aspiration, bone marrow biopsy, and collection of blood samples at pre-transplant and post-transplant. ARM B: Patients receive clofarabine IV over 2 hours on days -6 to -2. Patients also undergo TBI followed by HCT on day 0. Patients undergo ECHO or MUGA and lumbar puncture pre-transplant and undergo bone marrow aspiration, bone marrow biopsy, and collection of blood samples at pre-transplant and post-transplant. After completion of study intervention, patients are followed up at days 28, 56, 84 and 180, years 1 and 1.5 and then annually for 5 years.