Clinical Trial for Longevity Drug Meets Goal of Enrolling 1000 Dogs

The STAY study, a major clinical trial by biotech company Loyal, has reached its milestone of enrolling 1,000 senior dogs across 70 U.S. Veterinary clinics to test LOY-002—a developmental drug aimed at extending healthy lifespan in dogs. The goal has now expanded to 1,300 participants to strengthen the study’s scientific power. LOY-002, administered as a daily beef-flavored pill, targets improved metabolic health to delay age-related diseases. The trial also assesses dogs’ quality of life, not just longevity, based on pet owner feedback.

The first participant joined in December 2023, and the 1,000th, Winston the dachshund, was enrolled in Indiana. The FDA recently accepted the Reasonable Expectation of Effectiveness (RXE) portion of Loyal’s conditional approval application, a key regulatory milestone. Loyal’s team sees this study as both a path to FDA approval and a valuable resource for understanding canine aging. Ultimately, the goal is to help dogs live longer, healthier lives through science-backed care.