Imsidolimab (development code ANB-019) is an investigational, fully human monoclonal antibody being developed for the treatment of auto-inflammatory skin diseases, most notably generalized pustular psoriasis (GPP) and palmoplantar pustulosis (PPP). It functions as a selective interleukin-36 receptor (IL-36R) antagonist. By binding with high affinity to IL-36R, imsidolimab blocks the receptor from interacting with its pro-inflammatory ligands (IL-36α, IL-36β, and IL-36γ). This blockade inhibits the downstream activation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, thereby suppressing the intense neutrophilic inflammation and pustule formation that characterize these debilitating skin diseases.