Treatment of donor bone marrow with monoclonal anti-T-cell antibody and complement for the prevention of graft-versus-host disease. A prospective, randomized, double-blind trial

The effects of ex-vivo depletion of T lymphocytes from donor bone marrow using a monoclonal anti-T-cell antibody (CT-2) and complement on the outcome of allogeneic bone marrow transplantation was evaluated in a prospective, randomized, double-blind study of 40 patients with leukemia. Patients receiving T-cell-depleted bone marrow had a lower incidence of acute graft-versus-host disease than control patients (3 of 20 compared with 13 of 20; p = 0.004), and mortality due to acute graft-versus-host disease was reduced. Five patients in the T-cell-depletion group developed graft failure; all control patients had sustained engraftment (p < 0.05). Clinically apparent relapse of leukemia occurred in 7 patients from the T-cell-depletion group and in 2 controls (p, not significant). Cytogenetic evidence of residual leukemia was also detected in the 5 patients with graft failure without overt relapse. Infections and overall survival were similar in the two groups. The effects of T-cell depletion on engraftment and recurrence of leukemia require further evaluation.