A Pilot Study of Unrelated Umbilical Cord Blood Transplantation in Adults and Children With Bone Marrow Failure Syndromes or Inherited Metabolic or Hematologic Diseases

OBJECTIVES: I. Determine the rates of durable engraftment in patients with severe aplastic anemia, myelodysplastic syndrome, inborn errors of metabolism, or inherited hematopoietic disorders refractory to medical management, who are undergoing high dose chemoradiotherapy followed by unrelated cord blood (UCB) transplantation. II. Determine the incidence and severity of acute and chronic graft-versus-host disease in these patients. III. Monitor overall and event-free survival of these patients. IV. Evaluate rate and quality of immunologic reconstitution of these patients. V. Determine whether nucleated cell or progenitor cell content of the graft is predictive of engraftment.

OUTLINE: This is a multicenter study. Patients are stratified according to low vs high weight. Patients with severe aplastic anemia, myelodysplastic syndrome, or bone marrow failure receive cyclophosphamide IV over 1 hour on days -6 to -3 or melphalan IV over 20 minutes on days -4 to -2, antithymocyte globulin (ATG) IV over 4 hours or methylprednisolone IV over 1 hour twice a day on days -3 to -1, and total lymphoid irradiation on day -1. On day 0, patients receive umbilical cord blood (UCB) infusion. Patients with inborn errors of metabolism or inherited hematopoietic disorders receive oral busulfan every 6 hours on days -9 to -6, cyclophosphamide IV over 1 hour on days -5 to -2 or melphalan IV over 20 minutes on days -4 to -2, and ATG IV over 4 hours or methylprednisolone IV over 1 hour on days -3 to -1. On day 0, patients receive UCB infusion. Patients with Fanconi's anemia receive ATG IV over 4 hours or methylprednisolone IV over 1 hour on days -6 to -1, cyclophosphamide IV over 1 hour on days -5 to -2, thoracoabdominal irradiation on day -1, and then the UCB infusion on day 0. Patients also receive cyclosporine and methylprednisolone beginning on day -2 and continuing as necessary as graft-versus-host disease prophylaxis. Patients are followed indefinitely for survival and late toxicity.

PROJECTED ACCRUAL: A total of 4-90 patients will be accrued for this study within 5 years.