PROBLEM TO BE SOLVED : To provide a method of treating a human subject having relapsed and/or refractory multiple myeloma.SOLUTION : The method comprises administering to the human subject an antibody that specifically binds CD38, where the antibody is administered to the human subject in a safe therapeutic dose of about 1 mg/kg to about 20 mg/kg. The antibody is capable of killing a CD38+ cell in the human subject by induction of apoptosis, antibody-dependent cell-mediated cytotoxicity (ADCC), and complement-dependent cytotoxicity (CDC).SELECTED DRAWING : NoneCOPYRIGHT : (C)2019, JPO&INPIT