Richard Markus, MD, PhD, from Amgen, Los Angeles, CA, talks to us about a symposium at the European Society for Medical Oncology (ESMO) 2017 conference in Madrid, Spain which focused on biosimilars in cancer treatment. Dr Markus discusses ABP 980, a biosimilar of the agent trastuzumab developed by Amgen, and talks us through some of the other topics presented during the symposium.