Nadunolimab (also known as CAN04) is a fully human IgG1-kappa monoclonal antibody that targets the interleukin-1 receptor accessory protein (IL1RAP), a co-receptor essential for signaling of multiple pro-inflammatory cytokines in the IL-1 family (including IL-1α, IL-1β, IL-33, and IL-36). As an IgG1 isotype, it is designed to engage immune effector functions such as antibody-dependent cellular cytotoxicity (ADCC). By binding to IL1RAP, nadunolimab blocks cytokine-mediated signaling and may also deplete IL1RAP-expressing cells in the tumor microenvironment. It is being developed as a potential therapeutic for advanced solid tumors, with a focus on non-small cell lung cancer (NSCLC) and pancreatic ductal adenocarcinoma, often in combination with chemotherapy.