Ensuring Transfusion Safety for Multiple Myeloma Patients Receiving Anti-CD38 Monoclonal Antibody Therapy

Monoclonal antibody (mAb) therapy has shown promise for patients with relapsed multiple myeloma (MM), a discovery leading to the FDA’s 2015 approval of two mAbs, elotuzumab (anti-SLAMF7) and daratumumab (anti-CD38), for use in relapsed MM patients. This marks the first approved use of mAbs in MM treatment—and brings new challenges for clinicians who manage patients with MM.

It was recently observed that use of anti-CD38 mAb therapy in MM patients yielded false-positives in routine blood compatibility tests (panreactivity), producing interference that complicates pretransfusion testing and potentially delays the transfusion of appropriate blood products. Several approaches to mitigating this interference have been investigated, as has the use of phenotyping and genotyping to facilitate accurate crossmatching of antigen-matched donor RBCs for patients receiving anti-CD38 mAb therapy. However, many institutions do not yet have procedures in place to inform transfusion services when a patient is scheduled to begin taking anti-CD38 mAb therapy, an omission that can lead to delays in issuing RBC units to patients.