Updates to Clinical Information on Anticancer Immunotherapy

ABSTRACT

OBJECTIVE: Over the last several years, immunotherapy has become one of the most promising therapeutic options for cancer. This study aims to summarize the updates on cancer immunotherapy focusing on immune checkpoint inhibitors, such as programmed cell death-1 (PD-1), programmed death-ligand 1 (PD-L1), and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors, which have received attention as new anticancer therapeutic agents. METHODS: A literature survey was carried out on PubMed to identify high-impact papers on cancer immunotherapy from 2010. The most recent data on clinical efficacy and safety have been included highlighting the response characteristics to recently approved immunotherapeutic agents. RESULTS: In various cancers, immune checkpoints are a means for cancer cells to evade the immune system. Furthermore, CTLA-4 and PD-L1 can be overexpressed, allowing malignant cells to evade T-cells. Numerous clinical trials have been performed to seek appropriate indication of these products in various cancer types. Among them, the most conspicuous types are melanoma, non-small-cell lung cancer, and head and neck cancer. The approval of ipilimumab by Food and Drug Administration (FDA) commenced a new era of cancer immunotherapy. This was followed by the approval of nivolumab and pembrolizumab. Currently, combination therapies are being investigated for various cancer types. CONCLUSION: In this study, we reviewed recently reported scientific and clinical evidence for currently approved immune checkpoint inhibitors. Although these novel checkpoint inhibitors are ever evolving for cancer therapies, there exist limitations that need to be overcome, indicating the necessity for further studies aiming to improve their efficacy, toxicity, and cost.