Full Stage Lay Summary Tumours often have areas of low oxygen concentration (hypoxia), which cause the tumours to become more aggressive and harder to treat by standard therapy, resulting in poorer outcomes for patients. We have developed a novel class of drugs that specifically target these hypoxic zones in tumours. In this study we will identify an optimised compound of this class for clinical development. Furthermore, in order to select patients who will benefit most from the drug we must understand the factors (in addition to hypoxia) that determine the sensitivity of individual tumours. We will identify genes whose expression correlates with drug sensitivity in human cancer cell lines. The ultimate goal is to be able to profile patients for sensitivity in future clinical trials. Our team includes people highly experienced in cancer pharmacology, design and synthesis of anticancer drugs, and computer-assisted analysis of gene expression in cancer.