New Leap of Life Could a drug give your pet more dog years?
A team of academic researchers is currently conducting a canine clinical trial of rapamycin, which has been shown to extend the lives of lab mice.
The life of a pet dog follows a predictable trajectory. Over time, the floppy-eared puppy that keeps falling asleep in his food bowl will become a lanky-legged adolescent with an interest in squirrels — before eventually settling into adulthood as a canine creature of habit, with a carefully chosen napping location and a well-rehearsed greeting ritual. But as the years progress, his joints will stiffen and his muzzle will gray. And one day, which will inevitably arrive too soon, his wagging tail will finally still.
“When you adopt a dog, you’re adopting future heartbreak,” said Emilie Adams, a New Yorker who owns three Rhodesian Ridgebacks. “It’s worth it over time because you just have so much love between now and when they go. But their life spans are shorter than ours.” In recent years, scientists have been chasing after drugs that might stave off this heartbreak by extending the lives of our canine companions.
The biotech firm Loyal announced that it had moved one step closer to bringing one such drug to market. “The data you provided are sufficient to show that there is a reasonable expectation of effectiveness,” an official at the U.S. Food and Drug Administration informed the company in a recent letter. (Loyal provided a copy of the letter to The Times.)
That means that the drug, which Loyal declined to identify for proprietary reasons, has met one of the requirements for “expanded conditional approval,” a fast-tracked authorization for animal drugs that fulfill unmet health needs and require difficult clinical trials. The drug is not available to pet owners yet, and the F.D.A. must still review the company’s safety and manufacturing data. But conditional approval, which Loyal hopes to receive in 2026, would allow the company to begin marketing the drug for canine life extension, even before a large clinical trial is complete. “We’re going to be going for claiming at least one year of healthy life span extension,” said Celine Halioua, the founder and chief executive of Loyal.
Whether the drug will actually deliver on that promise is unknown. Although a small study suggests LOY-001 might blunt metabolic changes associated with aging, Loyal has not yet demonstrated that it lengthens dogs’ lives. But the letter, which came after years of discussion between Loyal and the F.D.A., suggests that the agency is open to canine longevity drugs, Ms. Halioua said.
More are in the pipeline. A team of academic researchers is currently conducting a canine clinical trial of rapamycin, which has been shown to extend the lives of lab mice. And Loyal is recruiting dogs for a clinical trial of another drug candidate, dubbed LOY-002. These developments are a sign of the accelerating pace of the science and the seriousness with which researchers and regulators are taking a field that once seemed like science fiction. They also raise questions about what it might mean to succeed, said Daniel Promislow, a biogerontologist at the University of Washington and a co-director of the Dog Aging Project, which is conducting the rapamycin trial.
Aging may be an inevitability, but it is not an unyielding one. Scientists have created longer-lived worms, flies and mice by tweaking key aging-related genes. These findings have raised the tantalizing possibility that scientists might be able to find drugs that had the same life-extending effects in people.
