BACKGROUND: Immune modulation in cancer refers to a range of treatments aimed at harnessing a patient's immune system to achieve tumour control, stabilisation, and potential eradication of disease. A novel therapeutic drug class called immune checkpoint-blocking antibodies modulate T-cell pathways that regulate T cells and have the potential to reinvigorate an antitumour immune response. Ipilimumab was the first FDA-approved immune checkpoint antibody licensed for the treatment of metastatic melanoma (MM) and blocks a checkpoint molecule called cytotoxic T-lymphocyte antigen 4 (CTLA-4). METHODS: Herein we review the preclinical and clinical development of ipilimumab. We outline the mode of action of these agents and other immune checkpoint inhibitors, the management of their toxicities, and how to adequately assess response to treatment. RESULTS: As a result of these data, a number of other antibodies that block novel checkpoint molecules including programmed death-1 (PD-1), and corresponding ligands such as programmed death ligand-1 (PD-L1) are under preclinical and clinical development, and have demonstrated activity in multiple tumour types. CONCLUSIONS: This review will summarise the mechanism of action and clinical development of immune checkpoint antibodies, as well as lessons learned in the management and assessment of patients receiving these agents.
