A pioneering Bay Area startup—Loyal—is now testing its LOY-002 daily pill on nearly 1,300 senior dogs, aiming to add at least one healthy year to their lives.
Loyal, a San Francisco–based biotech startup, is spearheading the first-ever large-scale lifespan extension trial in dogs with its drug LOY-002, aimed at senior canines aged 10 and older and weighing at least 14 lb. The STAY study, enrolling over 1,200 dogs across 70 veterinary clinics nationwide, marks the largest veterinary clinical trial in history.
Earlier this year, the FDA granted the drug its Reasonable Expectation of Effectiveness (RXE) designation—the first time this regulatory milestone has been granted for a canine longevity therapy. Loyal aims to complete safety and manufacturing validations for conditional FDA approval by the end of 2025.
LOY-002 is a beef-flavored daily tablet that targets metabolic dysfunction, a core driver of aging-related health decline in dogs. The goal is not immortality, but a longer, healthier life—extending functionality by at least one year, according to the company.
CEO Celine Halioua envisions this as part of a broader push to transform animal—and eventually human—longevity. Dogs share similar age-related diseases and environments with humans, making them ideal healthspan models.
The $22 million B-2 funding round brings Loyal’s total investment to over $150 million, cementing the company’s position at the forefront of the canine longevity field.
