Phase III Trial of T Lymphocyte Depletion by Elutriation and CD34 Add-Back for Allogeneic Bone Marrow Transplantation

OBJECTIVES:

• Compare the effectiveness, in terms of incidence of graft failure and incidence of greater than grade 1 acute graft-vs-host disease, of ex vivo manipulation of bone marrow cells comprising counterflow centrifugal elutriation for T-lymphocyte depletion followed by CD34-positive stem cell selection using CliniMACS vs Isolex 300i in patients with a hematologic malignancy undergoing allogeneic bone marrow transplantation from an HLA-identical sibling donor.

OUTLINE: This is a randomized study. Patients are stratified by age (< 40 vs 40-65) and disease status (low-risk [i.e., chronic phase chronic myelogenous leukemia, acute myeloid leukemia in first complete remission (CR), acute lymphocytic leukemia in first CR, Hodgkin's or non-Hodgkin's lymphoma in sensitive relapse, or multiple myeloma in CR or partial remission) vs high-risk [i.e., all others]). Patients are randomized to 1 of 2 treatment arms.

• Arm I: Allogeneic bone marrow cells are subjected to counterflow centrifugal elutriation (CCE) for T-lymphocyte depletion. The elutriation fractions are then processed over 2-2.5 hours using CliniMACS to select for CD34-positive stem cells.
• Arm II: Allogeneic bone marrow cells are subjected to CCE for T-lymphocyte depletion. The elutriation fractions are then processed over 4-4.5 hours using Isolex 300i to select for CD34-positive stem cells.

Patients in both arms then undergo ex vivo manipulated, T-lymphocyte-depleted, CD34-positive stem cell-selected, allogeneic bone marrow transplantation on day 0.