Previous studies demonstrated macrophage membrane‐coated nanomaterials had improved biocompatibility and prolonged blood circulation time.[44] As the naturally occurred exosomes of macrophages with excellent compatibility, DDRi@CAT‐PD‐M1Exos also had prolonged circulation time compared with free drugs, and Anti‐PD‐L1 on exosomes further improved the tumor‐targeting ability, eventually leading to the improvement on drug efficacy. The gene discussed is CD274; the disease is neoplasm.