Reduced-toxicity conditioning regimen with busulfan, fludarabine, rATG, and 400 cGy TBI in pediatric patients undergoing hematopoietic stem cell transplant for high-risk hematologic malignancies.

BACKGROUND Myeloablative conditioning regimens decrease the risk of relapse in pediatric patients undergoing allogeneic hematopoietic stem cell transplant (HCT) for hematologic malignancies, but cause significant toxicities PROCEDURE: This prospective study evaluated the use of a reduced-toxicity, myeloablative regimen with dose-adjusted busulfan, fludarabine, antithymocyte globulin and 400 cGy of total body irradiation in 40 patients   4000 μmol*min/day with two-year relapse-free survival approaching 80% CONCLUSIONS: This conditioning regimen is safe and effective in patients with high-risk leukemias, particularly myeloid disease. Larger studies are needed to compare its safety and efficacy to other myeloablative regimens in this population.