Survey Highlights Challenges in Blood Compatibility Testing for Patients on Monoclonal Antibodies

A recent survey published in Transfusion illustrates the challenges faced by hospital transfusion services when performing compatibility testing for patients on monoclonal antibodies. Nearly 75% of transfusion services reported difficulties with compatibility testing for patients taking anti-CD38 (daratumumab) and anti-CD47 (magrolimab) monoclonal antibodies.

Monoclonal antibodies are increasingly used to treat various hematological malignancies and other disorders. However, daratumumab (Darzalex) and magrolimab (Hu5F9-G4) target antigens that are also present on red blood cells (RBCs). This overlap can complicate the detection of clinically significant RBC alloantibodies, potentially delaying blood transfusions and impacting patient safety.

The survey, conducted among U.S.-based AABB member transfusion services, achieved a 27% response rate. Of the 240 respondents, 72% reported difficulties with compatibility testing for patients on daratumumab, while 73% encountered issues with magrolimab. A notable concern was the lack of notification about patients’ use of these drugs; 12% of respondents reported insufficient communication regarding daratumumab, and 25% for magrolimab.

To address these issues, transfusion services have adopted several strategies. The most common actions included referring samples to reference centers (50% of respondents), conducting blood group pheno/genotyping before starting treatment (41%) and using specific treatments such as 0.2 M dithiothreitol (DTT) or K-negative red cell units (36%).

According to the authors, the findings demonstrate that transfusion services are having challenges with the transfusion management of patients taking therapeutic monoclonal antibodies. The findings also underscore the importance of timely communication between clinicians and transfusion services to ensure effective care for patients taking these drugs.