Immune checkpoint blockade targeting programmed death ligand-1 (PD-L1) has emerged as a cornerstone of cancer immunotherapy, yielding durable responses in subsets of patients across multiple malignancies. However, clinical outcomes remain limited because of incomplete blockade, low tumor immunogenicity, and poor targeting specificity. Here, we report the development of a chondroitin sulfate-modified liposomal formulation (OPCR-Lip) designed to achieve comprehensive PD-L1 blockade while reprogram