Monoclonal Antibody-Purged Bone Marrow Transplantation Therapy for Multiple Myeloma

This report describes the clinical characteristics, treatment associated toxicity, and follow-up of fifty-eight patients with plasma cell--dyscrasias treated with high dose chemotherapy and total body irradiation (TBI) at a single institution. Following TBI, 36 patients received anti-B cell monoclonal antibody (MoAb)-treated autologous bone marrow, 21 patients received anti-CD6 cell MoAb-treated allogeneic bone marrow to deplete T cells, and one patient received unpurged bone marrow from a syngeneic donor. Evaluation after high dose chemotherapy and bone marrow transplantation (BMT) demonstrated 26 complete responses (CR), 26 partial responses (PR), 2 non-responders, 1 not yet evaluated, and three toxic deaths. Fourteen of 36 patients who underwent autologous BMT are alive free from progression at 18 (range 5 to 68) months post transplant (post-BMT); of these, 11 remain in continuous complete response at 16 (range 5 to 68) months post-BMT. Seven of 21 patients who underwent allogeneic BMT are alive free from progression at 30 (range 4 to 44) months post-BMT; of these, three patients remain in continuous complete response at 43 (range 33 to 45) months post-BMT. These data suggest that high dose chemotherapy with TBI followed by MoAb purged BM can be performed with acceptable toxicity and high tumor response rates.