Kevin Harrington, PhD, MBBS, Institute of Cancer Research and the Royal Marsden NHS Foundation Trust, London, UK, discusses the PATRIOT trial (NCT02223923), a Phase I study to assess the tolerability, safety and biological effects of the ATR inhibitor AZD6738 as a monotherapy and in combination with palliative radiation therapy in patients with advanced solid tumors. This interview took place at the European Society for Medical Oncology (ESMO) 2019 congress in Barcelona, Spain.