CTLA4 and hepatocellular carcinoma: More recently, the standard of care for 1L advanced HCC has shifted to immuno-oncology (IO)-based regimens, including atezolizumab (anti–programmed death-ligand 1) + bevacizumab (anti–vascular endothelial growth factor), approved in 2020, durvalumab (anti–programmed death-ligand 1) + tremelimumab (anti–cytotoxic T-lymphocyte associated protein 4), approved in 2022, and nivolumab (anti–programmed death-1) + ipilimumab (anti–cytotoxic T-lymphocyte associated protein 4), approved in 2025.2–4