The invention provides a method of treating a patient having target cells that express Fc³RIIb, the method comprising administering (i) an antibody molecule that specifically binds a surface antigen of the target cell, which antibody molecule has an Fc domain capable of binding Fc³RIIb； in combination with (ii) an agent that prevents or reduces binding between the Fc domain of the antibody molecule and Fc³RIIb； characterized in that the patient is selected on the basis that their target cells express an elevated level of Fc³RIIb.
