Preventing Stem Cell Transplant Complications With a Blood Separator Machine

Peripheral blood stem cell transplant research carried out by the NHLBI BMT Unit focus on transplant techniques designed to decrease graft versus host disease (GVHD), increase the graft-versus-leukemia (GVL) effect and reduce the risk of post-transplant graft rejection. Through incremental transplant clinical trials we have shown that by controlling the stem cell (CD34+ cell) and T lymphocyte (CD3+ cell) dose, severe GVHD can be reduced whilst beneficial GVL effects can be preserved. We found that T cell depleted transplants using the Nexell/Baxter Isolex 300i system and subsequently, the Miltenyi CliniMACS\[registered\] CD34+ system to obtain high CD34+ doses depleted of lymphocytes were safe to administer and associated with less severe acute GVHD and promising response rates and overall survival. Our previous trials have helped us to create the transplant environment (significant lymphodepletion and minimal post transplant immunosuppression) that make for an ideal platform for adoptive cellular immunotherapy. Adoptive cell transfer is the passive transfer of immune cells, into a new recipient host with the goal of transferring the immunologic functionality and characteristics into the new host. This protocol is designed to evaluate the safety and efficacy of the Miltenyi CliniMACS\[registered\] CD 34 selection system in HLA-matched sibling allogeneic peripheral blood stem cell transplant. The manipulation of the graft is the primary research intervention, subject to IDE# 15632, and all other aspects of clinical management on this protocol are standard care. The target CD34+ dose range will be \>3 x 10(6)/kg and the target CD3+ dose range will be 5 x 10(4)/kg to 1 x 10(6)/kg. Once we demonstrate adequacy of this platform for engraftment and absence of significant GVHD in ten consecutive recipients, we will seek IRB permission to proceed with planned adoptive cellular therapies. The protocol will accrue up to 96 transplant recipients aged 10-80 with a hematological malignancy and their HLA-matched sibling donors, in whom allogeneic stem cell transplantation from an HLA-matched sibling would be routinely indicated. Diagnostic categories will include acute and chronic leukemia, myelodysplastic syndromes, lymphomas, multiple myeloma and myeloproliferative syndromes. Subjects will receive a myeloablative conditioning regimen of cyclophosphamide (120 mg/kg total), fludarabine (125 mg/m(2) total) and total body irradiation (1200 cGy with lung shielding to 600 cGy), followed by an infusion of a stem cell product selected for CD34+ progenitors using the Miltenyi CliniMACS\[registered\] system. Older subjects will receive a lower dose of irradiation (800 or 600 cGy based on age) to reduce the regimen intensity. The overall objective is to assess the feasibility of using this system as a platform for cellular immunotherapy initiatives. The primary study endpoint will be overall survival at day +200. Stopping criteria for safety will monitor non-relapse mortality at day +200 and late disease free survival at 2 years. Secondary endpoints will be standard transplant outcome variables such as non-hematologic toxicity, incidence and severity of acute and chronic GVHD and relapse of disease.