Development of a Procedure to Resolve Daratumumab Interference in Pretransfusion Testing

ABSTRACT Multiple myeloma is an incurable disease characterized by the proliferation of malignant plasma cells in bone marrow. Daratumumab (DARA), a monoclonal antibody that targets CD38 antigen expressed on cells, has been approved as promising new treatment for patients with this disease. Although it effective medication, DARA presents challenges transfusion medicine. Because normal red weakly express antigen, panreactivity observed during antibody-detection workups treated DARA; can mask presence any underlying alloantibodies. The American Association Blood Banks (AABB) issued method how to resolve interference managing reagent dithiothreitol (DTT), which cleaves disulfide bonds antigen. primary objective study was develop protocol resolving pretransfusion testing at University North Carolina Medical Center’s Transfusion Medicine Services based described AABB. Optimal procedural conditions required 4 drops DTT 1 drop packed phosphate-buffered saline–washed incubated 37 °C 45 minutes. An screen using untreated and DTT-treated appropriate quality-control results indicated successful eliminating DARA-induced panreactivity. A cost analysis performed consider expenses time implementation in-house procedure.