Tacrolimus (FK506) and cyclosporine (cyclosporin A, CsA) are cornerstone
immunosuppressive agents administered to solid organ transplant recipients to prevent and
treat allograft rejection. The discovery of cyclosporine in the 1970s, and its entry into the
collection of immunosuppressants in the early 1980s, was a major breakthrough in
medicine. Cyclosporine was the most successful antirejection drug to date, and it radically
improved the chance of survival for transplant recipients. In 1994, the Food and Drug …