LILRB4, also known as ILT3, is an immune-modulatory transmembrane protein found on antigen presenting cells (APCs). LILRB4 is expressed on certain hematologic cancer cells and on certain pathogenic cells involved in autoimmunity and inflammatory processes.

IO-202 is a first-in-class antagonist antibody with specific, high affinity binding to LILRB4 and blocks binding of LILRB4 to ligands (ApoE, Fibronectin). IO-202 is a humanized IgG1 antibody with Fc effector function to kill LILRB4hi cells via antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). As such, IO-202 is a targeted therapy with broad potential in both blood cancers, as well as autoimmune and inflammatory diseases.

In hematologic malignancies, IO-202 has shown targeted depletion of leukemia blasts expressing LILRB4. In vitro and in clinical trials, IO-202 has also shown targeted depletion of LILRB4-expressing immune cells critical in pathogenic pathways of autoimmune and inflammatory diseases. IO-202 has the potential to be the best-in-class antibody therapy for lupus and can extend to other indications in immunology and inflammation (I&I). We expect to file an IND in 2024, leveraging a strong safety profile in over 70 cancer patients so far. Immune-Onc owns the world-wide rights to IO-202.