IMFINZI 500 mg Injection IMFINZI contains Durvalumab, a human immunoglobulin G1 kappa (IgG1κ) monoclonal antibody that selectively binds to programmed cell death-ligand 1 (PD-L1) and blocks its interactions with PD-1 and CD80 receptors. By relieving PD-L1-mediated immunosuppression, it restores and enhances T-cell activation and immune surveillance against tumor cells. It is indicated for the treatment of unresectable Stage III non-small cell lung cancer (NSCLC), extensive-stage small cell lung cancer (ES-SCLC), locally advanced or metastatic biliary tract cancer (BTC), and unresectable hepatocellular carcinoma (HCC).