The biotech company Loyal is working on a new drug designed to extend the lifespan of large- and giant-breed dogs. Code-named LOY-001, the veterinary-administered treatment earned U.S. Food and Drug Administration approval for a reasonable expectation of effectiveness, part of the conditional approval application.
“Developing a treatment that will increase longevity by reducing age-associated disease is a new indication,” said Dr. Linda Rhodes, an expert in animal drug development whom Loyal quoted in a press release. “No drug has ever been approved with such a claim, and being the first to bring a treatment for such a challenging indication will be truly historic.”
Loyal CEO Celine Halioua said the “milestone is the result of years of careful work by the team.”
Researchers believe that genetic selection emphasizes using bodily resources for speedy early growth in larger dogs instead of strengthening the immune system, repairing damaged DNA and improving stress resistance. In addition, they suggest that the same mutations that increase body size in dogs also raise the cancer risk.
Selective breeding of large dogs results in elevated insulin-like growth factor 1 (IGF-1) levels, a critical biomarker that drives cell growth. Large dogs have up to 28 times the IGF-1 levels as small dogs. LOY-001 works by reducing IGF-1.
“The extreme phenotypic variety found in dogs is not natural. It’s the result of intensive breeding by humans to create dogs that excelled at tasks such as herding, protection and companionship,” said Brennen McKenzie, Loyal’s director of veterinary medicine.
LOY-001 is intended as a long-acting drug given to dogs every three to six months. If the FDA gives final approval, LOY-001 should be available in 2026.