Quality Improvement Initiatives To Improve Transfusion Safety And Efficiency For Patients Receiving Daratumumab

Introduction: Daratumumab is an IgG1k monoclonal antibody directed against CD38, a surface glycoprotein expressed on several cell types including erythrocytes and B lymphocytes at various stages in development, including bone marrow precursors and plasma cells. It was initially approved by the FDA in 2015 for the treatment of multiple myeloma and has since garnered additional approvals in other settings leading to a growing number of patients receiving daratumumab. Its anti-B lymphocyte properties are therapeutic in myeloma patients; however, it also binds CD38 on erythrocytes and circulates for up to six months after a dose. This creates a long-term problem when caring for these patients regarding transfusion needs and resources. In particular, daratumumab causes antibody screens to be panreactive, potentially masking the presence of clinically relevant antibodies. Mitigation of this effect requires specialized treatment with dithiothreitol (DTT)-treated reagent erythrocytes to release CD38 from the cell membrane. This step allows for more accurate detection of clinically relevant antibodies, with the noted exception of the Kell system as these antigens are also removed.