This startup raised $250 million to help dogs live longer

Loyal has brought in more than $250 million as it pushes a new class of canine medicine toward regulators, betting that pet owners will pay for something the industry has never offered before: more healthy years with their dogs.

Biotech investors have spent years chasing therapies aimed at slowing aging in humans, but one of the most closely watched longevity companies is starting with dogs. San Francisco-based Loyal said on February 11, 2026 that it had raised $100 million in Series C funding, bringing its total funding to more than $250 million. The company’s goal is straightforward and emotionally powerful: develop prescription drugs that help dogs stay healthier for longer.

The lead program, called LOY-002, is a daily beef-flavored pill designed for senior dogs. Rather than suppressing appetite, Loyal says the drug is meant to mimic some of the metabolic benefits associated with calorie restriction, an area of research long linked to healthier aging. That distinction matters. Dog owners may be interested in extending a pet’s life, but few want to do it by making their animal less eager to eat or harder to train. Loyal’s pitch is that it can target age-related decline without weakening one of the central rituals of dog ownership: food, rewards, and shared routine.

That combination of scientific ambition and mass-market appeal helps explain why investors have written increasingly large checks. Loyal sits at the intersection of several durable trends: the humanization of pets, rising spending on veterinary care, and growing belief that aging itself can be treated as a biological process rather than accepted as an untouchable fact of life. For pet owners, the value proposition is not abstract. A therapy that adds even one healthy year to a dog’s life could be meaningful in a way few consumer health products can match.

The company’s founder and CEO, Celine Halioua, launched Loyal in late 2019 after working at The Longevity Fund, where she had a close view of the science and investment case behind anti-aging research. Dogs offered a more practical path than humans for turning that interest into a real product. They share homes, habits, and many environmental exposures with people, but they age much faster, allowing researchers to evaluate interventions on a shorter timeline. In other words, dogs may offer not only a commercial opportunity, but also a faster proving ground for the broader longevity field.

LOY-002 appears to be the company’s clearest near-term shot at commercialization. Loyal has said it has already cleared two of the three major milestones required in the FDA’s expanded conditional approval pathway: target animal safety and reasonable expectation of effectiveness. The final step is demonstrating that the drug can be manufactured consistently at scale. If that hurdle is cleared, the company believes the review process could move relatively quickly for a veterinary drug that would represent a first-of-its-kind claim around lifespan extension.

The target population for LOY-002 is also notable. Loyal expects the product to be aimed at dogs at least 10 years old and weighing at least 14 pounds. That framing suggests the company is pursuing a broad market rather than a narrow niche, focusing on older companion animals where age-related decline is visible to owners and veterinarians alike. Loyal has also indicated that pricing could land below $100 per month for the average dog, an important threshold if it wants the drug to become a recurring health expense rather than a luxury purchase reserved for a small slice of owners.

The scale of the company’s clinical work has added to the attention around it. Loyal has enrolled roughly 1,300 dogs across 72 veterinary clinics in a study known as STAY, which it describes as the largest animal health clinical trial of its kind. The company has said it hopes the data will show at least one additional healthy year for participating dogs. That is an ambitious benchmark, but it also reflects how Loyal is positioning itself. This is not being marketed as a supplement, a wellness brand, or a premium food line. It is being built as regulated medicine, with efficacy and manufacturing standards that have to withstand scrutiny.

Loyal is not stopping with one product. It also has two additional longevity programs in development, including a veterinary injection called LOY-001 and another daily pill called LOY-003. Those candidates are aimed in part at large-breed dogs, which typically live shorter lives than smaller dogs. The company’s thesis is that by targeting biological pathways associated with size and growth, it may be able to counter one of the tradeoffs built into decades of selective breeding.

The bigger significance of Loyal’s raise is what it says about the longevity category itself. Anti-aging science was once treated as speculative at best and unserious at worst. That is changing. Capital is now flowing to companies trying to turn the biology of aging into approved therapies, and veterinary medicine may prove to be one of the first places where that idea reaches the market. If Loyal succeeds, it will not just have built a major pet health business. It will have helped establish a new template for how longevity treatments get validated, commercialized, and eventually translated into human medicine.

For now, though, the company’s promise remains grounded in a simple emotional truth: dog owners never feel they get enough time. Loyal has raised a quarter of a billion dollars on the belief that science can do something about that, and investors appear convinced that the market, the medicine, and the moment may finally be lining up.