LOGAN – The popular weight loss drugs Ozempic, Rybelsus and Wegovy have their roots right here in Utah. The weight loss drugs came from an unlikely source. The same venomous Gila Monster that can kill or maim a human with one bite is the source for the weight loss drugs used by millions across the country.
A Gila Monster is a large, venomous, heavy-bodied lizard with orange, tan or yellow coloring with a black head and black patterns on their back. In Utah, they are found mostly in Washington County, but they also roam the deserts of Arizona, Colorado, California and New Mexico.
An undated photo showing the body of the Gila Monster. They can grow up to 22 inches long.
The cumbersome lizard is a carnivore that survives on a diet of tortoise and bird eggs, as well as baby cottontail rabbits and other small mammals that can’t move very fast.
Gila Monsters can grow up to nearly two feet in length and are the largest lizard in North America. It can eat up to 33 percent of its body weight in a single meal and only eats three to four times a year. The reptile spends 95 percent of its time below ground while its food digests.
Ann Mcluckie, a Division of Wildlife Resources biologist in Washington County, said Gila Monsters don’t burn energy to maintain a constant internal temperature like mammals do.
“Instead, Gila Monsters regulate their body temperature through their behavior and environment,” she said. “Their slow metabolism allows them to survive on just a few meals per year. In fact, three meals of juvenile cottontail rabbits can sustain them for an entire year.”
The ability of Gila Monsters to process food and energy slowly caught the attention of scientists studying blood sugar regulation in humans.
Mcluckie said researchers discovered a unique hormone found in Utah Gila Monsters’ saliva, called exendin-4. The researchers acquired one from a Utah Gila Monster breeding zoo for their study.
“This peptide is similar to GLP-1 but remains active in the body much longer and doesn’t break down quickly, making it a promising treatment tool. Amazingly, the Utah Gila Monster specimen helped confirm that these lizards naturally produce exendin-4 in their salivary glands,” she said. “That discovery provided the genetic blueprint for a synthetic version called exenatide, marketed as Byetta, which was approved in 2005 as a treatment for type 2 diabetes.”
Ozempic was developed as a newer synthetic drug that mimics GLP-1, inspired by the discovery of exendin-4 in Gila Monster saliva.
Mcluckie said milking venom from live animals is expensive and not a likely method for mass production of the drug. Researchers found a more cost-effective approach would be to produce a synthetic version.
“In people, a hormone called GLP-1 (a peptide) is released after eating. It stimulates insulin production after a meal when glucose is high, slows how fast the stomach empties, and helps regulate blood sugar levels,” she said. “However, GLP-1 breaks down in the body within minutes, limiting its potential for use as a drug. Researchers discovered a unique hormone in Gila Monster saliva, specifically from an animal that originated from southwestern Utah, called exendin-4.”
The Utah Gila Monster specimen helped confirm the these lizards naturally produce exendin-4 in their salivary glands.
A Reeds Pharmacy employee hold a box of Ozempic, a weight loss and diabetic drugs was derived from Gila Monster saliva
There may be more research being done on Gila Monster saliva due to its chemical complexities and its history in helping to produce a novel drug to help with type 2 diabetes. One of the recent research studies showed that Gila Monster saliva could help locate pancreatic tumors.
“The two scientists who authored a recent paper on the new novel method to scan for pancreatic tumors used a modified synthetic version of the hormone, exendin-4, found in Gila Monsters,” Mcluckie said. “Their new novel method made it easier to locate small or hard-to-find pancreatic tumors, increasing the detection rate of these tumors to 95 percent. Once again, Gila Monster saliva has led to an important medical tool for humans.”
There is much more research being done on the effects and advantages of Ozempic and other weight loss drugs from saliva from the reptile.
Pew Research Center reported Ozempic, Rybisus, and Waygovy had a combined sales of $21.1 billion for Novo Nordisk, a company that produces them, in 2024.