Researchers at the Texas A&M College of Veterinary Medicine & Biomedical Sciences (VMBS) have been awarded a $7 million grant from the National Institutes of Health (NIH) to broaden the scope of a clinical trial evaluating rapamycin's capacity to extend the lives of companion dogs. This initiative is part of The Dog Aging Project (DAP), a collaborative research endeavor between the University of Washington School of Medicine and Texas A&M, among other institutions.
The DAP, launched in 2019, enrolls companion dogs to study aging's effects, seeking insights into factors contributing to long and healthy canine lives, which may translate to human aging knowledge. To date, over 50,000 dogs have been enrolled in the study.
TRIAD: Testing Rapamycin in Aging Dogs
The Test of Rapamycin In Aging Dogs (TRIAD) is the third clinical trial by DAP to investigate rapamycin, a generic drug commonly used as an immunosuppressant in human organ transplant recipients. Prior DAP studies indicated that small doses of rapamycin could improve cardiac function in dogs.
"As both people and animals age, the heart begins to stiffen, making it beat less effectively," explained Dr. Kate Creevy, DAP chief veterinary officer and a professor at VMBS. "Evidence from laboratory studies suggests that rapamycin can improve heart muscle function, cognitive function, and mobility, as well as extending lifespan."
The trial has currently enrolled 170 dogs across 20 sites. The new funding aims to expand the study to include 580 dogs and add more locations nationwide.
Translational Potential for Human Health
While the trial primarily focuses on healthy aging in dogs, TRIAD's outcomes could also benefit human anti-aging medicine. According to Dr. May Reed, a geriatrician at the University of Washington School of Medicine, dogs experience similar age-related cognitive, sensory, neuropathologic, and mobility changes as older humans. The possibility that rapamycin might delay alterations contributing to cognitive impairment and functional decline is exciting and has translational potential.
Rapamycin and its Anti-Aging Mechanisms
Rapamycin, also known as sirolimus, is typically used to prevent organ rejection in kidney transplant patients. However, DAP's research suggests that low doses of the drug may help mitigate or delay aging-related diseases.
"Rapamycin works by modifying the cells' energy balance and energy handling," Creevy stated. "It seems to mimic the effects that happen in people or animals who do intermittent fasting...and some of the pharmaceutical effects of rapamycin make the same changes at the cellular level."
While dogs do not share all common human aging diseases, such as coronary artery disease, there is hope that rapamycin could benefit human patients with heart disease by improving heart muscle function.
Enrollment in TRIAD
TRIAD is actively seeking to enroll more dogs in the trial. Eligible dogs must be over 7 years old, in good general health, and weigh at least 44 pounds (20 kg). Owners must commit to bringing their dogs to participating clinical sites every six months for three years, following an initial visit for baseline health information.
Participating sites include neurology and cardiology centers across the country, with more locations expected to be added. Dogs must first enroll in the DAP's overall health and aging study, which requires owners to complete and update a health and life experience survey annually.
