age1 leads Series C as Loyal advances LOY-002 toward FDA approval, completing key requirements for conditional approval.
Loyal, the clinical-stage animal health company developing what it hopes will become the first FDA-approved drug for lifespan extension, has raised $100 million in a Series C financing led by age1, the next generation of Laura Deming’s Longevity Fund. Baillie Gifford participated alongside existing investors. The raise follows a year in which the company completed two of the three major technical requirements for FDA Expanded Conditional Approval for its lead program, LOY-002, and finished enrollment of STAY, its pivotal efficacy trial involving more than 1,300 dogs across over 70 veterinary clinics nationwide.
The capital is intended to carry Loyal from late-stage development into market readiness – a transition that, in drug development terms, is less about theory and more about documentation, manufacturing and distribution. LOY-002 is designed as a daily pill for senior dogs, intended to target metabolic pathways associated with aging in order to extend healthy lifespan. The company has previously reported that the FDA’s Center for Veterinary Medicine has accepted both the Reasonable Expectation of Effectiveness and Target Animal Safety sections for LOY-002 as part of the Expanded Conditional Approval pathway.
Longevity.Technology: Loyal’s $100M Series C is easy to read as a capital vote, but it is really a regulatory vote – money arriving precisely because the unromantic mechanics of approval are now visible. By completing two of the three technical requirements for FDA Expanded Conditional Approval for LOY-002, and by fully enrolling its pivotal nationwide STAY study across more than 70 clinics, the company is doing something longevity biotechs are often accused of avoiding: operationalizing prevention at scale, in a real-world population, with endpoints regulators can interrogate. Dogs make this more than a feel-good detour; they are companion animals living in our exposures and our homes, and they offer a biologically plausible model of aging that moves fast enough to be tested within a commercial timeline. If age1’s lead and Baillie Gifford’s participation signal anything, it is that “longevity” becomes more investable the moment it starts to look like a product dossier rather than a philosophy.
From concept to dossier
For Loyal’s founder and CEO Celine Halioua, the financing marks both validation and obligation. “Our driving purpose at Loyal is to help dogs live longer, healthier lives,” she said. “We’re closer than ever to delivering a solution to the problem we set out to solve: an FDA-approved drug for canine lifespan extension. This capital will help our team see our lead program through the remaining FDA requirements and get to market [1].”
The FDA’s Expanded Conditional Approval pathway permits early approval of certain animal drugs based on a reasonable expectation of effectiveness, provided full demonstration of effectiveness is subsequently confirmed. Loyal has now secured acceptance of its safety and initial effectiveness data for LOY-002; what remains is the final demonstration of substantial evidence of effectiveness, supported by data from STAY, which the company describes as the largest clinical trial ever conducted in animal health [2].
Scale matters. Enrolling over 1,300 privately owned dogs in a longevity-focused trial introduces variability – breed, diet, environment, comorbidities – that laboratory models smooth away. It also brings the study closer to the conditions under which a commercial product would actually be used. Companion dogs age in our kitchens and backyards, not in controlled vivaria; their diseases are entangled with obesity, inactivity and environmental exposures that mirror our own.
Investors and a preventive thesis
The investor mix reflects a maturing narrative around aging therapeutics. Alex Colville, Cofounder and General Partner of age1, framed Loyal’s trajectory in explicitly cultural as well as scientific terms. “Loyal has created a scientific and cultural movement towards proactive therapeutics for aging,” he said. “Very few realize the impact this has had to date and the impact it will have to come. The way we understand and approach aging will never be the same [1].”
Such language would once have felt aspirational. Today, it sits alongside regulatory correspondence and trial enrollment figures. For Baillie Gifford, a firm known for long-horizon growth investing, the attraction lies in the combination of preventive medicine and commercial discipline. “Celine and the team are redefining how preventive care is approached in veterinary medicine,” said Tom Slater, partner at Baillie Gifford. “Helping dogs live longer, healthier lives matters to many families. By combining scientific rigour with a clear regulatory plan, Loyal has the foundations to build a substantial business in a large and expanding market [1].”
But behind the rhetoric is a simple economic observation: pet owners will routinely pay out of pocket for interventions that promise incremental gains in health or longevity. Add to this that veterinary medicine, which is less constrained by reimbursement codes than human healthcare, and you have an early proving ground for therapies that target aging biology, and do it directly rather, than treating its downstream complications one organ at a time.
The canine model and its limits
Dogs occupy a particular place in translational research. They share our homes, our pollutants and often our waistlines; they develop age-related diseases that resemble human pathologies, from osteoarthritis to certain cancers. Their shorter lifespans compress timelines, allowing interventional studies to read out within years rather than decades. Yet they are not small humans, and regulatory success in veterinary medicine does not automatically confer efficacy in people.
Even so, the conceptual step is notable. To seek approval for a drug intended to extend lifespan in a healthy aging population is to test the proposition that aging can be a legitimate therapeutic target, not merely an inevitability to be managed symptom by symptom. In that sense, LOY-002 functions as both product candidate and policy experiment.
A proving ground for prevention
If LOY-002 achieves Expanded Conditional Approval and proceeds to market, the implications will extend beyond veterinary shelves. Longevity science has long wrestled with endpoints, biomarkers and evidentiary thresholds, but in this case, those debates are being translated into pill bottles and prescribing guidelines. Quietly radical and entirely practical.
For now, Loyal’s task is execution – completing the remaining FDA requirements, scaling manufacturing and preparing veterinarians for a new category of therapy. Should it succeed, the first routinely prescribed longevity drug may arrive not in a geriatric clinic, but in a vet’s exam room.
Main image shows Abby, aged 13. Photographs courtesy of Loyal. Photograph of Alex Colville courtesy of age1
[1] https://www.businesswire.com/news/home/20260211301175/en/Loyal-Raises-%24100M-Series-C-Led-by-age1-to-Advance-the-First-Canine-Longevity-Drug
[2] https://loyal.com/posts/100m-for-first-longevity-drug
