Immunotherapy and chimeric antigen receptor T-cell therapy in hepatocellular carcinoma

Advanced hepatocellular carcinoma (HCC) is a deadly disease. With increasing incidence of new cases over the last years multiple efforts have been made to ameliorate survival and quality of life. Recent advances in understanding the tumor microenvironment and cancer immune evasion led to development of potent immune therapies targeting programmed death-ligand-1 (PD-L1), programmed cell death protein 1 (PD-1) and anti-cytotoxic T-lymphocyte-associated protein-4 (CTLA-4). Early clinical studies highlighted the activity and synergism of checkpoint inhibitors with antiangiogenic drugs, including anti-vascular endothelial growth factor (VEGF) antibodies and multi-tyrosine kinase inhibitors. Most recently, the combination of bevacizumab and atezolizumab improved survival compared to sorafenib in the treatment of advanced HCC on first-line therapy in a randomized phase III trial and now is considered the standard of care. Multiple options are available for the treatment of metastatic HCC including atezolizumab, bevacizumab, nivolumab, pembrolizumab, ipilimumab, sorafenib, lenvatinib, regorafenib, cabozantinib and ramucirumab. Furthermore, other checkpoint inhibitors are being evaluated including durvalumab, tremelimumab, CS1003, sintilimab and camrelizumab. In this review article, we focus on the landscape of different immunotherapy strategies in the management of HCC and the combination of checkpoint inhibitors antibodies with antiangiogenics. In addition, we will address the limitation of cell therapies in advanced HCC and current strategies to improve efficacy.