Lifesaver

The 12,000 organ transplants performed in the U.S. each year are often successful only because the patients take a daily dose of cyclosporine. The drug keeps their immune systems from attacking and rejecting the foreign organs. But it is not perfect. Some 70% of patients getting a new liver, for example, still suffer rejection episodes. And many organ recipients face life- threatening side effects from cyclosporine, including an increased risk of cancer and heart disease.

Now a respected researcher who was one of the first to use cyclosporine may have found a better way to make transplants succeed. Dr. Thomas Starzl of the University of Pittsburgh, the world's largest transplant center, is expected to report in the British journal Lancet this week that a new drug, FK-506, is proving to be more powerful and less toxic than cyclosporine. In more than 100 patients taking FK-506 for up to eight months, the rate of organ rejection was only one-sixth as high as in those using cyclosporine. Side effects were minimal, though long-term consequences remain unknown. The Food and Drug Administration calls the preliminary research "very exciting," but approval for general use may be years away.

FK-506 works by suppressing the proliferation of certain white blood cells, the workhorses of the immune system. Starzl thinks the drug could signal a revolution in organ transplantation. Moreover, it could possibly lead to a treatment for diseases, like arthritis, that are caused by an overactive immune system.

Manufactured by Fujisawa Pharmaceutical of Osaka, FK-506 is derived from a soil fungus found in Japan. Starzl first learned of the drug in 1986 at a meeting in Helsinki. Other researchers had dismissed it because in studies using dogs it caused severe bleeding and other problems. But Starzl believed the reaction occurred in dogs alone and undertook a graduated series of experiments on several other animals, from rats to baboons. These tests were encouraging, and in February 1989 Starzl tried the drug on Robin Ford, a 26- year-old secretary who was in danger of rejecting her third liver. After two weeks of FK-506 treatments, she recovered completely. Says Ford: "It's incredible how great this drug is."

But FK-506 will not remove the most serious hurdle to transplants: the chronic shortage of donor organs. More than 18,000 Americans in need of transplants are waiting for organs to become available.