CD123 is a subunit of the dimeric interleukin-3 receptor (IL-3R), which belongs to the β common receptor family. This membrane receptor family plays a vital role in regulating the growth, proliferation, survival, and differentiation of hematopoietic cells, as well as in immune and inflammatory responses. CD123 is widely expressed in various hematologic malignancies, such as acute myeloid leukemia (AML), B-cell acute lymphoblastic leukemia, hairy cell leukemia, Hodgkin lymphoma, and blastic plasmacytoid dendritic cell neoplasm (BPDCN). Furthermore, CD123 is lowly expressed in normal cells, making it an attractive target antigen (TAA) protein.
IMGN632 is an antibody-drug conjugate (ADC) targeting CD123 that was granted Breakthrough Therapy Designation (BTD) by the US FDA in October 2020. In addition to ADCs, the field of bispecific antibodies targeting CD123 is also widely explored, with numerous companies focusing on this area, particularly CD123/CD3 bispecific antibodies. Research on CD123 in the CAR-T cell therapy field is also actively pursued.
