Transfusion management in the era of magrolimab (Hu5F9‐G4), an anti‐CD47 monoclonal antibody therapy

How do transfusion services manage patients taking therapies such as anti‐CD38 and anti‐CD47 known to interfere with red blood cell compatibility testing?

“…A recent review article summarized mitigation strategies such as blood group pheno/genotyping the patient in advance of starting the drug and emphasized the importance of timely communication between clinicians and transfusion services. 4 The lack of such communication was one of the most important findings of this survey. Another important finding was the recognition that advice about the transfusion management of these patients can be obtained from several sources.…”

“…If not managed appropriately, test turnaround times may be prolonged, and the provision of blood products delayed thus compromising patient care and safety. 4 It is uncertain how transfusion services are dealing with any problems encountered with compatibility testing and how they are managing the provision of blood for patients taking these drugs. This survey was conducted by contacting AABB member hospital transfusion services contacts.…”

“…Drugs such as daratumumab (Darzalex, anti-CD38) and Hu5F9-G4 (magrolimab, anti-CD47) may interfere with red blood cell compatibility testing as CD38 and CD47 are expressed on red blood cells. [1][2][3][4] Panreactive agglutination may occur in the standard indirect antihuman globulin (Antiglobulin test [AGT]) test used for antibody screening and crossmatching. Consequently, clinically relevant red blood cell alloantibodies may not be recognized in patients who need blood transfusion.…”

“…1 For patient samples affected by magrolimab, an anti-CD47 IgG4 monoclonal antibody, Gamma-clone anti-IgG, can be used as it lacks IgG4 reactivity. 4 While these methods are regularly used by immunohematology reference laboratories (IRL), they may be beyond the scope of most transfusion services and blood banks.…”