Karl serves as Chief Medical Officer at Achilles and leads the clinical development strategy. He is also a Professor of Transplant Science and Cancer Immunotherapy at UCL Cancer Institute, Scientific Director of the NIHR Blood and Transplant Research Unit for Stem Cells and Immunotherapies, and Clinical and Scientific Director of the Sir Naim Dangoor Centre for Cellular Immunotherapy at UCLH. Karl received his preclinical training and MA at Cambridge University, completing his clinical training at Oxford University Medical School. He completed his general medical training at Addenbrooke’s Hospital Cambridge, and specialist haematology training at the John Radcliffe Hospital, Oxford and subsequently UCLH, London. He spent over 2 years at Memorial Sloan Kettering Cancer Center NYC, USA in the laboratory of Professor James Allison studying murine models of regulatory checkpoint blockade and subsequently ran a joint Research Laboratory with Professor Sergio Quezada at the UCL Cancer Institute where his research interests included viral infections, adoptive cellular therapies, and regulatory checkpoint-directed immune-therapeutics and he and Sergio retain active links to the institute. More recently he has established the clinical translational side of the academic CAR T cell programme at UCLH.