Distribution of a human growth hormone being used by some athletes as a muscle-builder has been temporarily halted by the federal government because it is believed to carry an infectious virus suspected of killing three young adults since last November.
Officials of the Department of Health and Human Services believe the use of HGH caused the death of a man in his 20s from a rare and incurable virus called Creutzfeldt-Jakob disease. The man had used HGH as a child. Creutzfeldt-Jakob disease is degenerative brain disorder. The virus, known as a prion, is believed to be the cause of the disease.
Doctors also suspect two other deaths--one in February and one in April--were caused by the contaminated drug.
Experts believe the virus resulted from use of the hormone that was processed before 1977. They hypothesize the virus contaminated the hormone in the purification process. Extensive improvements in purification methods were made in 1977.
The growth hormone is used to treat children and adolescents who have serious growth deficiencies. The injectable drug is extracted from the pituitary glands of human cadavers.
Dr. Albert F. Parlow, a research professor at UCLA Medical School, whose laboratory at Harbor-UCLA Medical Center in Torrance is the only one in the country that processes the pituitaries used to extract the growth hormone, said it will take at least 18 months to prove the currently produced hormone is safe.
The drug still can be obtained illegally in the U.S., said Dr. Robert Kerr, a San Gabriel physician, who gave the growth hormone to two athletes within the past year. Kerr also has said he prescribes anabolic steroids to athletes.
"I am certain there is HGH available on the black market," he said. "Some athletes may still be getting it. It is obviously risky."
Doping control at the 1983 International Amateur Athletic Federation Track and Field World Championships at Helsinki showed that some athletes had used the drugs.
The growth hormone, some athletes claim, have an anabolic, or muscle building, effect. The drug is not on the International Olympic Committee's list of banned substances. In addition, there is a lack of agreement in the medical community on HGH's effects on athletes.
Further compounding the future research of HGH and other growth hormones is the development of a biosynthetic growth drug. Dr. Salvatore Raiti, the director of the National Hormone and Pituitary Program at the University of Maryland Medical School in Baltimore, believes the Food and Drug Administration soon will approve the synthetic drug because the natural product is unavailable.
Genentech of South San Francisco and KabiVitrum, a Swedish company, have been conducting clinical trials with the synthetic drug.
Susan Atkins, a Genentech spokesperson, said she doesn't expect the product to quickly gain approval because of the HGH ban. "The FDA has been receiving data from us since 1981," she said. "We don't see them speeding up the approval process. These things take a long time."
Dr. Raiti said most European countries that produce HGH still are using the drug after the recent findings. He said England and Canada have discontinued use.
The immediate concern is the treatment of 3,500 children and adolescents with pituitary disorders who no longer have access to the drug, doctors say. The national program was producing 50,000 pituitaries a year.
"I find this use by the athletes disgusting," said Dr. Gertrude Costin, a pediatric endocrinologist and physician to 50 hypopituitary patients at Children's Hospital in Los Angeles.
But one world-class athlete training for the Olympics said last year: "It goes back to this: I'm using STH (same as HGH) because it is not being tested for.