IMM47 is a potentially global first-in-class humanized monoclonal antibody targeting CD24 for cancer treatment. We have successfully screened IMM47 despite the fact that the screening of antibodies against CD24 is highly challenging due to the relatively weak immunogenicity resulting from its small extracellular domain. With its differentiated molecule design, IMM47 can specifically bind to CD24 and potently activate macrophage and NK cell-immune responses. IMM47 has been shown to significantly increase the amount of M1 macrophages (a subtype of macrophages that can fight infections and trigger inflammation to defend harmful invaders) in tumor tissues in our in vivo proof-of-concept studies. It can also activate and promote T-cell response likely through tumor antigen presentation and direct blockade of immune inhibitory signals. Our preclinical studies have demonstrated promising efficacy of IMM47. In addition, IMM47 can establish tumor-specific immune responses that prevent tumor growth even against re-inoculation of tumor cells in mice, demonstrating its capability to further induce T-cell-based adaptive immune activation.

Targeting both innate and adaptive immunity, CD24-targeted drugs present a significant potential in treating a wide range of cancer indications. Given the all-around immune responses stimulated by blocking the CD24/Siglec-10 signaling pathway, they also suggest a strong synergistic potential with other immunotherapies, including PD-1/PD-L1 inhibitors. In fact, our preclinical studies have shown that the combination of IMM47 and OPDIVO® or KEYTRUDA® can lead to a significant increase in response rates in our mouse model compared to using OPDIVO® or KEYTRUDA® alone.