Chemotherapy, Total Body Irradiation, and Post-Transplant Cyclophosphamide in Reducing Rates of Graft Versus Host Disease in Patients With Hematologic Malignancies Undergoing Donor Stem Cell Transplant

This phase Ib/2 trial studies how well chemotherapy, total body irradiation, and post-transplant cyclophosphamide work in reducing rates of graft versus host disease in patients with hematologic malignancies undergoing a donor stem cell transplant. Drugs used in the chemotherapy, such as fludarabine phosphate and melphalan hydrochloride, work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Giving chemotherapy and total-body irradiation before a donor stem cell transplant helps stop the growth of cells in the bone marrow, including normal blood-forming cells (stem cells) and cancer cells. When the healthy stem cells from a donor are infused into the patient, they may help the patient's bone marrow make stem cells, red blood cells, white blood cells, and platelets. Sometimes the transplanted cells from a donor can make an immune response against the body's normal cells (called graft versus host disease). Giving cyclophosphamide after the transplant may stop this from happening.

PRIMARY OBJECTIVES: I. To determine the cumulative incidence of extensive chronic graft versus host disease (GVHD) at 1 year after transplantation utilizing the novel conditioning/GVHD prophylactic regimen for patients undergoing allogeneic hematopoietic cell transplantation, in patients who do not progress before day 100. SECONDARY OBJECTIVES: I. To evaluate clinical response, engraftment rate, progression-free survival (PFS) at one year and, overall survival (OS). II. To determine the cumulative incidence of relapse. III. To evaluate the day 100 transplant-related mortality rate. IV. To determine the cumulative incidence of grade III-IV acute GVHD. OUTLINE: This is a dose-escalation study of melphalan hydrochloride. CONDITIONING REGIMEN: Patients receive fludarabine phosphate intravenously (IV) over 30 minutes on days -5 to -2 and melphalan hydrochloride IV over 30 minutes on day -2. Patients undergo total body irradiation (TBI) on day -1. STEM CELL INFUSION: Patients undergo allogeneic hematopoietic stem cell transplant on day 0. GVHD PROPHYLAXIS REGIMEN: Patients receive cyclophosphamide IV over 2 hours on days 3-4, mycophenolate mofetil IV over 2 hours on days 5-35, and tacrolimus IV and then orally (PO) once tolerated on days 5-180 with a taper beginning on day 100. After completion of study treatment, patients are followed up for 12 months and then annually thereafter.