To date, more than 4,000 patients who have received organ transplants at Pitt have been treated with the drug. Research indicates that FK506 is 50 to 100 times more powerful than cyclosporine, thus improving the one-year survival rates. With cyclosporine the survival rate for liver transplant patients after one year was 85 percent. With FK506 the survival rate at one year for these patients may be as high as 93 percent. Short-term side effects of FK506 include headache, vomiting, nausea and tingling of the feet.
Side effects tend to be less severe when given orally rather than intravenously.
Patients do not experience swollen gums and, for women, excessive hair growth that is common with cyclosporine. Long-term effects of FK506 are unknown. With the promising results of the initial research, further clinical evaluation was conducted through a multi-center trial. The trial, which involved the Mayo Clinic, University of California in Los Angeles, University of California in San Francisco, University of Nebraska and Baylor University Medical Center, compared the safety and efficacy of FK506 to cyclosporine in liver transplant recipients. Additionally, seven centers in Europe are experimenting with the drug, and the Osaka University Hospital in Japan is using FK506 with living-related organ recipients.