CD38 and plasma cell myeloma: The HexaBody-CD38 derived from the clinically approved antibody daratumumab showed potent anti-tumor activity in preclinical models of hematological diseases such as multiple myeloma (MM), B-cell malignancies and acute lymphoblastic leukemia (ALL), and the DuoHexaBody-CD37 may represent a potential therapeutic antibody for the treatment of certain B-cell malignancies (70, 71).