N-809

N-809 is a novel fusion protein designed as an immunotherapeutic agent that combines two functional domains: a PD-L1 blocking domain (derived from anti-PD-L1 antibody scaffolding) and an interleukin-15 (IL-15) superagonist domain, similar to N-803. It is intended to harness the immune system against cancer by both blocking the PD-1/PD-L1 immune checkpoint pathway and stimulating potent proliferation and activation of NK cells and CD8+ T cells. Preclinical studies demonstrate that N-809 enhances proliferation and activation phenotypes in CD8+ T cells and NK cells, upregulates activation receptors and cytolytic molecules, and leads to increased tumor cell lysis in vitro. N-809's dual mechanism is designed to address immunosuppression in the tumor microenvironment and overcome resistance to checkpoint blockers while providing strong immune stimulation. The primary developer is ImmunityBio.