At the European Society for Medical Oncology (ESMO) 2014 Congress, Dr Rachel Humphrey (Senior Vice President, Head of Immuno-Oncology, AstraZeneca) discusses the anti-programmed death-ligand 1 (PD-L1) monoclonal antibody, MEDI4736, which is being evaluated in phase I/II studies in patients with various advanced solid tumour types. The combination of MEDI4736 with the anti-cytotoxic T-lymphocyte-associated protein 4 (CTL-4) monoclonal antibody, tremelimumab, is being studied in patients with non-small cell lung cancer.