Drug to Extend Dog Lives Receives Encouraging News

A California biotech company that's pioneering a drug aiming to extend the lifespan of dogs said it cleared a vital hurdle, as the medication gained a portion of conditional approval by the U.S. Food and Drug Administration (FDA).

Loyal, a San Francisco-based company founded in 2020, has been researching ways to increase the lifespan of dogs, particularly large and giant breeds, the biotech company said in a statement on Tuesday, which added that "today's announcement shows the FDA believes Loyal's approach is valid."

The FDA Center for Veterinary Medicine has approved the "reasonable expectation of effectiveness" section of Loyal's conditional approval application for LOY-001, the name of the drug the company is developing to both extend the lifespan of big dogs and maintain their quality of life, Loyal spokesman Tim Smith said in a statement.

While Loyal did not specify in the statement how long the drug could extend the lives of large canine companions, the company says on its website that the drug will be a "long-acting injectable" administered by a veterinarian every three to six months. At the time of publication, the estimated cost of the drug had not been released.

Smith said the FDA's expanded conditional approval is an "accelerated pathway" for the drug, which Loyal estimates will be available in 2026.

"Today's milestone is a crucial part of Loyal's application for conditional approval," Smith said. "It means the FDA agrees LOY-001 has a reasonable expectation of effectiveness and, once the FDA approves Loyal's manufacturing and safety data packages, Loyal can market the drug for lifespan extension in the target canine population. Conditional approval lasts for up to five years, during which time Loyal will collect the remaining effectiveness data and apply for full approval."

A spokesperson for the FDA told Newsweek on Tuesday that the agency could not comment on applications that are in progress.

The FDA Center for Veterinary Medicine has reviewed Loyal's findings, which included data, results and scientific arguments, and determined that the information provides "reasonable expectation of the drug's effectiveness to extend canine lifespan and healthspan," Smith said in the statement.

The drug still has to successfully complete its "manufacturing and safety" sections of its application before it receives conditional approval, which will allow the biotech company to market LOY-001 for "large-dog lifespan extension," he said.

Loyal CEO Celine Halioua, in a statement sent to Newsweek on Tuesday, described the FDA's nod of approval on the section of the application as a "milestone."

"Loyal was founded with the ambitious goal of developing the first drugs to extend healthy lifespan in dogs," Halioua said. "This milestone is the result of years of careful work by the team. We'll continue to work just as diligently to bring this and our other longevity programs through to FDA approval."

Selectively breeding dogs has caused elevated levels of the growth-promoting hormone IGF-1, which is believed to reduce their lifespan, according to Loyal, which says that big dogs have vastly more of the hormone than small pooches, with the latter known to live nearly twice as long.

"LOY-001 works by reducing IGF-1 in adult dogs to increase lifespan," Smith said.

The goal of LOY-001 is to treat age-associated diseases by "targeting mechanisms" of aging to prevent or delay the onset of those diseases rather than waiting for the animals to get sick before administering treatment.

Loyal said part of the research included in the FDA application was the results of a "large observational study" involving 452 dogs of 84 different breeds from ages 2 to 18. The study, according to Loyal, showed "LOY-001's ability to reduce levels of key biomarker IGF-1 and the beneficial impact on functional outcomes in dogs."

Despite the FDA's "milestone" ruling on Tuesday, some experts and animal advocates are leery that the drug can do what it claims, fearing it'll extend animals' suffering instead, according to a report by The New York Times. The outlet reported that experts say more testing and clinical studies have to be completed before LOY-001 is proven to extend the life of dogs.