Comparative analysis of alpha radioimmunotherapy with bismuth-213-labeled anti-CD138 antibody and Melphalan chemotherapy for the treatment of multiple myeloma.

Abstract

Multiple myeloma (MM) is a B-cell malignancy of terminally differentiated plasma cells that proliferate within the bone marrow, secrete a monoclonal immunoglobulin in serum and urine and induce osteolytic bone lesions in human. Despite intense research to develop new treatments, cure is almost never achieved. Alpha-radioimmunotherapy (alpha RIT) has been shown to be effective in vivo in a mouse multiple myeloma model and seems particularly suited for a disease characterized by disseminated tumor cells and small clusters of tumor cells. CD138 (Syndecan-1) is found mainly in epithelial cells, but has been shown to be expressed by most myeloma cells, both in human and in mouse. In order to define where alpha RIT stands in MM treatment, the aim of this study was to compare Melphalan (MM standard treatment) with alpha RIT using a bismuth-213-labeled rat anti-mouse CD138 antibody in a syngeneic mouse MM model.