A New Drug That Could Extend Dogs’ Lives Inches Closer to Approval

For the first time, the FDA has indicated a willingness to endorse a longevity drug

a white dog in a sunny field with trees in the background
San Francisco-based startup Loyal is developing drugs that aim to extend dogs' lifespans—and it could form a basis for longevity research in humans. LordHenriVoton via Getty Images

For most dog owners, the idea of extending their beloved companion’s life is tantalizing. A dog’s lifespan—about 10 to 13 years—is only a small portion of the average human’s, and some breeds, especially larger ones, have an even shorter life expectancy. 

“When you adopt a dog, you’re adopting future heartbreak,” Emilie Adams, a New York resident who owns three Rhodesian Ridgebacks, tells Emily Anthes of the New York Times. “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.”

Now, the San Francisco-based biotech company Loyal has announced its anti-aging drug for canines cleared the first of several hurdles needed for approval by the Food and Drug Administration. While the drug still must undergo clinical trials, this marks the first time the FDA has indicated a willingness to endorse longevity drugs, writes Hilary Brueck for Business Insider

Scientists have long been interested in ways to slow the aging process and extend life. Previous research on roundworms edited two cell pathways to extend their lifespans by 500 percent. Earlier this year, scientists reportedly reversed signs of aging in mice.

But aging in more complex and longer-lived organisms such as humans has proved more difficult to hack. For one, clinical trials would need to span decades before researchers could collect any data, which would get very pricey. However, Loyal CEO Celine Halioua thinks dogs, which face similar age-related ailments at roughly the same time in their life as humans do, might be a good model for our own longevity. 

“If a big dog is, you know, getting sick and dying from age-related diseases at age seven, eight, nine, he’s going gray at age four. He’s getting a limp at age five,” Halioua tells Aleks Krotoski of the BBC series “Intrigue: The Immortals.” “The rate of aging is so high that you can tell if a drug is impacting that in about 6 to 12 months. In 6 to 12 months, you’re not going to see anything in a person.” 

Loyal’s drug, called LOY-001, is an injection-based treatment that targets a growth and metabolism hormone called IGF-1. This hormone seems to be size-related—it appears in higher levels in larger dogs and in lower levels in smaller dogs. Research has shown that inhibiting IGF-1 in flies, worms and rodents can increase their lifespans, per Wired’s Emily Mullin. However, the hormone is not the only factor seemingly associated with canine longevity.

LOY-001 is designed for healthy dogs over the age of seven and above 40 pounds, and it would be administered every three to six months by a veterinarian. The company is also simultaneously working to develop a daily pill called LOY-003. 

“We’re not making immortal dogs, to be clear, but that rate of aging will be slower, hopefully, which means the pet will be in a healthier state for longer,” Halioua tells Megan Rose Dickey of Axios. “And that’s fundamental to all of the biology of what we’re doing.”

Notably, manipulating the way that animals age brings up a host of ethical conundrums, including questions into how their quality of life would be affected. 

“If it proves true that it extends life span, I’m only interested in that if the period of life that is extended is good quality life,” Kate Creevy, a veterinarian at Texas A&M University and the chief veterinary officer of the Dog Aging Project, which is conducting a trial into a different anti-aging drug for dogs called rapamycin, tells the Times. “I don’t want to make my dog live an extra two years in poor health.”

Per Loyal, humans have been manipulating dogs through selective breeding for years, which may have contributed to large dogs’ accelerated aging in the first place. 

The company plans to begin a large clinical trial for LOY-001 with about 1,000 large and giant dogs in either 2024 or 2025, with the goal of having a product on the market by 2026, reports Wired.

Get the latest stories in your inbox every weekday.