Bispecific antibodies specific for treating hematological malignancies

A method of treating a hematological malignancy expressing a CD38 antigen and/or a B cell maturation antigen (BCMA) in a subject, the method comprising:

• administering to the subject a therapeutically effective amount of a first bispecific affinity reagent, wherein the first bispecific affinity reagent comprises a first binding domain that binds to a CD38 antigen, and wherein the first binding domain comprises an amino acid sequence included in an amino acid sequence of the bispecific affinity reagent as set forth in any one of SEQ ID NOs:
• 2, 4, or 6, and a second binding domain that binds to a yttrium-DOTA (Y-DOTA) ligand, wherein the second binding domain that binds to the Y-DOTA ligand comprises an amino acid sequence as set forth in any one of SEQ ID NOs:
• 20-36;
• administering to the subject a therapeutically effective amount of a second bispecific affinity reagent, wherein the second bispecific affinity reagent comprises a first binding domain that binds to the BCMA, and wherein the second binding domain comprises an amino acid sequence as set forth in any one of SEQ ID NOs:
• 8 or 10, and a second binding domain that binds to a Y-DOTA ligand, wherein the second binding domain that binds to the Y-DOTA ligand comprises an amino acid sequence as set forth in any one of SEQ ID NOs:
• 20-36 and
• thereafter;
• and administering to the subject a therapeutically effective amount of the Y-DOTA ligand.