he Gila Monster is a stout-bodied lizard that grows 18 to 24 inches in length. Native to the American southwest, it is one of only two species of seriously venomous lizards. But thanks to the curiosity of a relatively unknown medical researcher, the study of the Gila Monster’s toxic saliva has led to a major breakthrough in the treatment of diabetes, a scourge variously reported as the fifth or sixth deadliest disease in the United States.
Diabetes is the inability of the body to produce enough insulin to control the level of blood sugar, which can lead to such horrific consequences as stroke, blindness, kidney failure, amputations, and a host of other grim results. Most Type 2 diabetics, who are the 90 percent of diabetics not dependent on insulin, rely on a variety of oral medications to control their sugar levels, not always to good effect.
In the late 1980s, Dr. John Eng, an endocrinologist at the Bronx VA Medical Center in New York, performed studies confirming that Gila Monster venom stimulated the production of insulin. He found that a compound in the venom, which he named extendin-4, mimics a naturally occurring hormone that stimulates insulin production in the human body to lower blood sugar levels.
The problem with the human hormone is that enzymes in the blood cause it to degrade so rapidly that it is not practical to administer to diabetics for stimulating production of insulin. But Dr. Eng’s studies showed that the Gila Monster hormone doesn’t degrade for hours, making it a much better candidate for a drug.
Dr. Eng obtained a patent for a drug, called exenatide, based on a synthetic version of the Gila Monster saliva. In 1996, he licensed his discovery to Amylin Pharmaceuticals, a small biotechnology firm, which later entered into a partnership with pharmaceutical giant Eli Lilly to complete work on exenatide.
Given the commercial name Byetta (pronounced bye-A-tuh), exenatide was approved by the Food and Drug Administration in April 2005, and went on the market about 11 months ago. To say that it is taking the diabetes-care community by storm might be an understatement. In the first quarter of this year, for example, nearly $70 million of the product was sold and, according to Lilly spokesman Jamaison Schuler, Byetta has already become the fifth-most-prescribed branded diabetes medicine when physicians are writing a new prescription.
Byetta is a liquid that must be injected twice a day, an hour or less before breakfast and an hour or less before dinner. It can’t be taken in pill form because it is a protein that the stomach would break down rapidly like the proteins in the food you eat. So it comes in a pen which holds 60 doses, which is a month’s supply. It must be kept refrigerated between uses.
Byetta is easy to administer, with most patients performing the injections on the left and right sides of their abdomens. The pen uses a needle so thin that a majority of users say they don’t even feel it go in.
Patients must still take certain diabetes medications in pill form in conjunction with Byetta, though Byetta’s effectiveness often leads to a reduction in oral medications. And it is not for those who are on insulin.
Sounds like a big turn-off, doesn’t it? A drug that must be injected, that must be kept refrigerated, and doesn’t free you from all your diabetes pills?
Well, here are the benefits of Byetta that people are raving about: First, there is an immediate drop in blood-sugar levels as the drug stimulates the production of enough insulin to lower and control them. Second, most patients lose weight because Byetta has the effect of slowing the passage of food through the stomach, allowing patients to feel full while eating less, an important factor when you consider that obesity is a common diabetes indicator.
Endocrinologist James Snyder, medical director of the new Joslin Diabetes Center’s affiliate of the Fremont Medical Center in Las Vegas, participated in several clinical trials of Byetta and is enthusiastic about its potential. "It is a breakthrough product that addresses a physiology we were not previously aware of," he says. "And the weight-loss factor is an important bonus for patients on Byetta."
Joyce Malaskovitz, director of the Diabetes Treatment Center at Desert Springs Hospital, is also positive about Byetta. "We are a diabetes education service," she says, "so we’ve made sure to include information about Byetta in our classes. The response has been excellent, and we have found a high level of interest in this unique product."
Kevin Thorn, a physician assistant in the office of Henderson endocrinologist W. Reid Litchfield, says his office has put about 50 patients on Byetta since beginning to prescribe it about six months ago. "The most common side effect is nausea, especially when starting on Byetta," Thorn says. "But this has occurred in only about 5 percent of our patients, and the lowering of blood sugars, combined with weight loss, has generated real enthusiasm. We regard this as a major breakthrough in diabetes care."
I am on Byetta, by the way, and I regard it as a miracle in my life.
Written May, 2006.
Reproduced with permission of the author,
David Berman.
