Anti-myeloma activity of 213Bi-anti-CD38-MAb was investigated in vitro in terms of induction of DNA double-strand breaks, initiation of cell-cycle arrest in the G2/M-phase and eradication of MM cells as well as in a preclinical model of MM investigating tumor development, intratumoral apoptosis and survival of animals. The gene discussed is CD38; the disease is plasma cell myeloma.