Novel Radiopharmaceuticals for selective & efficient tumour cell killing

Radioactive isotopes can kill cells if they emit particulate radiation (alpha and beta particles). If the radioactivity can be selectively delivered only to cancer cells within the human body, it can be useful to treat cancer with minimal harm to the patient's normal tissues. This method of treatment, using the radioisotope iodine-131, cures many thousands of patients with thyroid cancer annually. To extend the benefit to patient with other cancers we propose to develop and evaluate new radioisotopes and understand their effects on cancer cells. Gallium-67 (67Ga) emits Auger electrons with a range commensurate with the size of tumour cells, and should therefore selectively kill the malignant cells to which they are targeted. Thus, by administering 67Ga as a ligand-metal complex linked to a molecule that binds specifically to the cancer, we envisage selectively killing the tumour while avoiding significant healthy tissue toxicity. We will synthesise novel chelators with high affinity for 67Ga, develop completely new chemistry needed to carry even more potent radioisotopes, which have not been explored so far, to tumours (e.g. thallium-201), and incorporate them into both small peptides and larger antibodies/antibody fragments. The new cancer therapies will be commercially and clinically developed for use in patients.