Pretransfusion testing interference profile of IMC-002: A novel anti-CD47 monoclonal antibody engineered for minimized red cell binding.

BACKGROUND: CD47-targeted agents can interfere with pretransfusion testing due to CD47 expression on red blood cells (RBCs). IMC-002 is a novel anti-CD47 human IgG4 monoclonal antibody engineered to minimize RBC binding; however, its interference profile during pretransfusion testing remains poorly characterized. STUDY DESIGN AND METHODS: Whole blood samples were incubated with IMC-002 and tested by tube, gel card, and automated methods for ABO/RhD typing, direct antiglobulin test (DAT), and RBC phenotyping. Plasma spiked with IMC-002 underwent antibody screening by tube and gel methods, adsorption studies, and carryover assessment. Flow cytometry compared IMC-002 binding between RBCs and T cells. RESULTS: IMC-002 interfered with ABO/RhD typing, DAT, and antibody screening, but the extent varied by assay. Forward grouping interference was mitigated by saline washing. In contrast, reverse grouping interference was most prominent in gel cards but was resolved in tube testing via saline replacement. Antibody screening showed panreactive false-positive results, which were stronger in gel cards and with papain-treated RBCs. However, the magnitude of interference was lower than that reported for other CD47-targeted agents. Flow cytometry confirmed minimal IMC-002 binding to RBCs compared to dose-dependent binding to CD3+ T cells. CONCLUSIONS: IMC-002 exhibits a distinct pretransfusion interference profile compared with previously reported CD47-targeted agents. Its interference appears partly mitigable by routine laboratory measures and is consistent with its engineered low RBC affinity, underscoring the need for agent-specific evaluation of CD47-targeted therapeutics in transfusion practice.