Of all the thoughts racing through my head the day we brought home our pandemic puppy, there’s only one I remember vividly: “Man, it’s gonna suck when you die.” There’s a reason it’s so devastating to lose a dog. They are the ultimate companion—non-judge-y, always pumped to see you, and happy to lick your tears. In fact, the death of a pet can hurt as much as the loss of a relative, according to an article in Society and Animals.
Three years later, I’ve made peace with the tradeoff, but my ears perked up like our German shepherd’s when I heard Beef series creator Lee Sung Jin give a shout-out to the FDA in his Emmy Award-winning speech, urging them to fast-track a “canine anti-aging pill.” Was it real or promo for an upcoming sci-fi show? Turns out a biotech company in San Francisco, aptly named LOYAL, is running clinical trials in the U.S. for drugs designed to extend a dog’s life expectancy.
Founder and CEO Celine Halioua is a dog lover who studied neuroscience and nanobiotechnology and was intrigued by the discrepancy in life expectancy between big and little dogs. Case in point: a chihuahua may live 16 to 18 years while a great dane might only live 6 to 8. LOYAL’s thesis is that the short lifespan of big dogs is like “an accelerated aging disorder, an unintended consequence of historical inbreeding for size and behavior traits. It created all the different dog breeds we have today, but it also created genetic mistakes,” says Halioua. German shepherds get hip dysplasia, flat face dogs like French bulldogs have breathing issues, and golden retrievers get cancer at much higher rates. In an effort to correct these mistakes, LOYAL’s drug LOY-1 reduces the insulin-like growth factor (IGF-1), a biomarker hormone, also present in humans, that drives cell growth and is key to regulating the aging process. The hope is that it will turn down this process to a more sustainable rate, so big dogs can have more healthy years. The injectable medication would be given by a vet every 3–6 months starting at age seven for dogs 40 pounds and up.
Don’t worry, they haven’t forgotten the smaller dogs. Clinical trials are now under way for LOY-2, a pill that aims to improve metabolic fitness for dogs of nearly all sizes, as well as LOY-3—a pill version of LOY-1. “Research is ongoing, but we expect they will help dogs get at least one extra year of healthy living,” says Halioua. “We hope that dogs would show less visible signs of aging if they are on treatment, but we don’t have any definitive information on this yet.”
Early results have been so promising that the FDA said the data provided “a reasonable expectation of effectiveness,” meeting one of the requirements for “conditional approval.” According to an FDA spokesperson, it must still evaluate safety and manufacturing data, among other things. Once these additional standards have been met, Loyal will be able to market it.
This is the first time the FDA has made such a move for a longevity drug, a striking vote of confidence in a field of research I’d assumed was more pipe dream than reality. So far researchers have successfully lengthened the lifespan of fruit flies, roundworms and mice by manipulating genes associated with aging. The hope is these victories will help scientists develop drugs and treatments for humans by targeting the same pathways. That said, model systems in labs don’t always translate to how humans live in the world—which means dogs could offer a new perspective. “The dog is an interesting model because they’re such close companions with humans,” says Idan Shalev, PhD., a longevity researcher and an associate professor of biobehavioral health at Penn State. “They have the same environmental exposures and develop similar age-related diseases.”
Roughly 20 to 30 percent of our longevity is genetically determined, according to research published in PLoS One. That means the rest of our life expectancy hinges on environmental factors that then change how our genes work in ways that increase or decrease our risk for age-related disease (a.k.a. epigenetics). “Studies have shown that people who are biologically older than their actual age tend to have worse health outcomes,” says Aladdin Shadyab, PhD, associate professor of public health and medicine at UC San Diego. “Identifying ways to slow biological aging, either through medications or a change in lifestyle behaviors is, to me, the most exciting area of longevity research.”
Several start-ups are now selling direct-to-consumer blood and saliva tests that claim to calculate biological age for both humans and dogs. Whether they are worth it, is still up for debate. “Biological clock tests are where the longevity field is heading, but I’m not sure the reliability is there just yet,” says Murphy. “Eventually all of this will be possible, and I do hope we can provide affordable options for people in the next decade.”
For now, I’ll focus on the science-backed habits that help extend lifespan for both humans and dogs: a healthy diet, regular exercise, sleep and companionship—which just so happen to be my dog’s favorite activities. Maybe the best longevity drug is curled up right under my feet.
A version of this article appears in the 2024 issue of ELLE.
Kelly Mickle is an ASME award-winning journalist with more than a decade of experience covering health, lifestyle and culture. She previously worked as an editor for Self magazine, is a cofounder of towwn and has written for Glamour, Women’s Health, Cosmopolitan, Sunset and more.