About this program
IPH4301 is a program to develop a first-in-class anti-MICA/B therapeutic antibody in oncology. MICA/B is a highly polymorphic ligand of the NK cell activating receptor NKG2D.
MICA/B expression is specifically induced in several highly prevalent solid tumors and with a high frequency (Colon, kidney, endometrium, melanoma, lung, liver, ovarian, breast).
Chronic exposure to MICA/B down-regulates NKG2D at the surface of NK and CD8 T cells, suppressing NKG2D+ NK and CD8 T cell activity. Furthermore, MICA/B expression can be induced on tumor associated, immuno-suppressive macrophages. Hence, targeting MICA/B with an antibody that is both ADCC-inducing and blocking NKG2D binding to MICA/B can act by a dual mechanism of action: tumor antigen targeting and immunomodulation.
IPH4301 is currently in IND-enabling studies.
Mechanism of action of anti-MICA/B
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