In memoriam: Professor Sir Roy Yorke Calne, MB, FRCS, FRS, FRCSC, Dec. 30, 1930, to Jan. 6, 2024

<h3>Summary:</h3> Kidney transplantation was experimental, with success confined to procedures involving identical twins, until the introduction of the anticancer drug, azathioprine, by Roy Calne in Joseph Murray’s Boston lab in 1962. It enabled expansion of this activity from a few laboratory-based centres to clinical programs throughout the world. As professor of surgery at Cambridge University, Dr. Calne began exploring liver transplantation. His clinic and that of Tom Starzl, then in Denver, were the only ones achieving success, however limited. Between them, they perfected the operation and solved the anesthetic and pre- and intraoperative difficulties. Despite the use of azathioprine, rejection rates among kidney and liver recipients were high. In 1976, Dr. Calne’s team explored the immunosuppressive properties of a novel fungal-derived drug, cyclosporine, first in laboratory animal models and then in patients. Their results altered the transplant landscape dramatically; the field rapidly expanded to include other organs and there was a rapid proliferation of both numbers of clinics and operations. Within another decade, Dr. Calne’s team introduced 2 more exceptional drugs, tacrolimus and rapamycin, and, finally, the monoclonal antibody alemtuzumab. Acclaimed surgeons are usually noted for their technical innovations. Dr. Calne was exceptional in that he also revolutionized the pharmacology of a field. His Canadian trainees established 3 of Canada’s 6 liver transplant programs.