As any dog owner knows, the lives of our furry friends are far too short, whizzing by in an instant. All too soon, we see ourselves experiencing the inevitable heartbreak of having to say goodbye. But, as scientists have been chasing after drugs that could extend our pets’ lives, could we soon stave off this heartbreak and see the approval of longevity drugs for dogs?
One company pursuing this goal is San Francisco-based biotech startup Loyal. The company currently has three drugs in development and under review with the U.S. Food and Drug Administration (FDA) Center for Veterinary Medicine (CVM). In this article, we take a closer look at how the three drugs work, and when each one might be approved.
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How do Loyal’s longevity drugs for dogs work?
Two of Loyal’s drugs – known as LOY-001 and LOY-003 – are focused specifically on extending the lifespan of large dogs.
Karen Greenwood, senior vice president of Regulatory and Strategy at Loyal explained to Labiotech that both LOY-001 and LOY-003 are intended for dogs seven years or older, and weighing at least 40 pounds. The difference between the two drugs largely comes down to how each one is administered. “LOY-001 will be a long-acting injection administered to dogs by their veterinarian every three to six months,” said Greenwood. “LOY-003 will be a tablet that the owner can give to their dog at home.”
Both of these longevity drugs work by correcting for an overexpression of growth hormone in mature dogs that is believed to lead to early mortality. This growth hormone is called insulin-like growth factor-1 (IGF-1). The IGF-1 pathway is associated with aging and longevity in several species, and is known to play a key role in dogs in determining body size. It is thought that high IGF-1 levels drive both rapid growth and accelerated aging in large dogs, which have shorter lifespans than smaller dogs. Celine Halioua, Loyal’s founder and chief executive explained in an article in The Guardian that the breeding of dogs for size over hundreds of years “basically gave them an unintentional genetic accelerated aging disorder.” According to Halioua, LOY-001 can successfully reduce IGF-1 levels in the blood in a week.
Meanwhile, the third longevity drug for dogs being developed by Loyal is code-named LOY-002. This is intended to extend lifespan and quality of life for senior dogs of nearly all sizes – except for the absolute smallest of breeds.
LOY-002 works slightly differently from LOY-001 and LOY-003, instead extending lifespan by improving dogs’ metabolic health to delay the onset and reduce the impact of age-associated diseases. “It’s a little bit more of a reversal mechanism. It’s not going to make a 10-year-old dog a puppy, but we’ve seen a rescuing in age-related functional decline in dogs that have been treated with this drug,” said Halioua, this time in an interview with dvm360.
A pivotal efficacy study called STAY was recently launched to test LOY-002. The trial will be the largest clinical study of its kind, conducted in partnership with more than 50 independent veterinary clinics and over 1,000 pet dogs.
During the study – which is expected to last four years – the company will collect data on LOY-002’s potential impact on the lifespan and quality of life of dogs receiving the drug, compared to those receiving a placebo pill. The company will also collect data on any adverse effects among the study population. The results of the study will then be shared with the FDA CVM as part of Loyal’s application for full approval of the longevity drug.
To facilitate the development of future products, Loyal will also build a longitudinal biobank of saliva and blood samples from participating dogs to further support its research.
The first dog – a whippet named Boo – has already been dosed as part of the study, and participating veterinary clinics and animal hospitals across the country will begin enrolling more dogs over the coming months.
Extending quality of life as well as lifespan
Of course, no dog owner wants to spend extra years with their four-legged companion just to see them in pain and suffering from ill health. This is why it is also important that, not only do Loyal’s drugs extend a dog’s lifespan, but they also ensure quality of life is extended, too.
“By targeting what we believe is the causative factor of premature mortality in large dogs, we aim to address the underlying mechanisms leading to age-associated increases in disease burden and reduced quality of life,” said Greenwood, also agreeing that quality of life is just as important as lifespan.
“The path to conditional approval includes data to demonstrate reasonable expectation of effectiveness alongside the same safety and manufacturing quality packages that are required for a fully approved drug. This data package is reviewed by the FDA CVM and includes the links between the mechanism of action and an expected effect on health and quality of life as well as lifespan.”
Therefore, pet owners can be assured that if Loyal’s longevity drugs for dogs become approved, they will still be able to witness their dogs finding joy in life.
FDA approval on the horizon for Loyal drugs LOY-001, LOY-002, and LOY-003
In a milestone achievement, Loyal announced in November last year that the FDA CVM approved the Reasonable Expectation of Effectiveness section of Loyal’s conditional approval application for LOY-001, which is essentially a formal acceptance that a drug can be developed and approved to extend lifespan.
As a result of this, according to Greenwood, it is now expected that both LOY-001 and LOY-003 will be available under conditional approval in 2026. And, dog owners could have access to longevity drug LOY-002 even sooner, as the company currently projects it will be available under conditional approval in early 2025, while Loyal continues to run its lifespan extension study in parallel.
If approved, Greenwood stated that all of Loyal’s products will be prescribed by veterinarians, “based on their clinical assessment of whether dogs meet the treatment criteria.” And, once begun, treatment would be continuous in order to achieve maximum benefit.
Could the approval of longevity drugs for dogs pave the way for human longevity drugs?
The possibility of extending dogs’ lives with longevity drugs has also raised the possibility that scientists might be able to find drugs with the same life-extending effects in people. Dogs are actually known to be very good models for human aging – far better than mice models, in fact.
Nir Barzilai, professor of genetics and medicine at the Albert Einstein College of Medicine in New York, explained in an interview with The Guardian, that this is because they “share our environment in such a respect that their microbiota is more similar to their owners than to other dogs.” Essentially, we eat similar foods and follow a similar lifestyle, plus our metabolisms work in much the same way, and we suffer the same diseases, such as cancer and cognitive decline.
Many longevity biotech companies are already on the case when it comes to developing anti-aging drugs for humans. However, they are yet to be proven in a clinical setting. If longevity drugs for dogs could help speed up the development of human anti-aging drugs, then the approval of Loyal’s candidates could be even more of a milestone achievement.
For now, though, Loyal’s longevity drugs could very soon bring immense joy to dog owners, most of whom know all too well just how little time we actually get to spend with our four-legged friends before we have to say our goodbyes.
New technologies related to dogs health:
- Noninvasive Heartworm Detection in Dogs – Auburn University
- Amylase Dog Stress Marker – University of Lincoln
- Drug Targeting Alleviation of Symptoms in AD Dog Patients – University of Ljubljana