Loyal's LOY-002 Clears Two of Three FDA Gates as the First Longevity Drug Approval in Any Species Nears

Loyal's LOY-002, a daily pill designed to extend healthy lifespan in senior dogs, has cleared two of three FDA technical gates after completing the largest clinical trial in veterinary medicine.

Loyal's LOY-002 Clears Two of Three FDA Gates as the First Longevity Drug Approval in Any Species Nears Loyal's LOY-002, a daily pill designed to extend healthy lifespan in senior dogs, has cleared two of three FDA technical gates after completing the largest clinical trial in veterinary medicine. Aaron Rafferty April 12, 2026 Key Takeaways: Loyal's LOY-002 has cleared two of three FDA technical sections required for Expanded Conditional Approval: Reasonable Expectation of Effectiveness in February 2025 and Target Animal Safety in January 2026. Manufacturing remains the final gate. The STAY study , Loyal's pivotal efficacy trial, completed enrollment of 1,300 dogs across 70 veterinary clinics nationwide in July 2025, making it the largest clinical trial in the history of veterinary medicine. If approved, LOY-002 would be the first FDA-approved drug intended to extend healthy lifespan in any species. Loyal has raised over $150 million across funding rounds including a $22 million B-2 led by Valor Equity Partners and Collaborative Fund. LOY-002 is a daily beef-flavored pill for dogs aged 10 years and older weighing at least 14 pounds. It works as a caloric restriction mimetic, delivering some of the metabolic benefits of severe caloric restriction without requiring dogs to lose weight or suppress appetite. "Arthritis and cancer and cognitive dysfunction are all different things," Loyal's director of veterinary medicine Brennen McKenzie told Fortune . "But really, aging and metabolic health is one aspect of that that drives all these different things. If we can pick off the underlying driver for all of these things, we can have a much greater impact." The STAY study is a randomized, double-blinded, placebo-controlled trial in which half of the 1,300 enr