Atezolizumab, sold under the brand name Tecentriq, is a monoclonal antibody medication used to treat urothelial carcinoma, non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC), hepatocellular carcinoma and alveolar soft part sarcoma. It is a fully humanized, engineered monoclonal antibody of IgG1 isotype against the protein programmed cell death-ligand 1 (PD-L1).