Cadonilimab (AK104) is a tetravalent PD-1/CTLA-4 bispecific humanised antibody that activates T cells by enhancing IL-2 and IFN-gamma secretion while reducing pro-inflammatory cytokine secretion (e.g., IL-6, IL-8). It offers low toxicity and high affinity, making it suitable for metastatic cervical, gastric, hepatic, and pulmonary cancers, pancreatic cancer, and oesophageal squamous cell carcinoma.