are being infused back into his body at university college hospital, london. all other cancer treatments have failed to stop his leukaemia returning. car—t is his best hope. it's a living drug inside me now. it's a medicine which lives in me and itjust replicates inside the bone marrow. every time it sees a sort of cancer cell, zap. fingers crossed? fingers crossed, yeah. car—t stands for chimeric antigen receptor t—cell therapy. part of the patient�*s own immune system, there t—cells, are removed from their blood. in a laboratory, these cells are modified. a gene is added to enable them to recognise their own cancer. this army of t—cells is multiplied and then infused back into the patient. a new protein on the surface of the t—cells locks on to the cancer, earmarking it for destruction.