Loyal expanded its STAY study of investigational LOY-002 from an original target of 1,000 dogs to as many as 1,300, and says the expanded study is now fully enrolled. The milestone means a larger study population—not proof that the drug works or approval to sell it.
Loyal’s current trial page reports 1,300 dogs enrolled across 70 veterinary practices. The reviewed sources do not report a STAY result showing that LOY-002 extends lifespan.
What changed in the STAY trial?
In April 2025, Loyal announced that STAY had reached its original enrollment goal of 1,000 dogs and that recruitment would expand by up to 300 participants. Loyal later reported that enrollment was complete in July 2025. Its current trial page describes the study as fully enrolled, with 1,300 dogs across 70 veterinary practices.
The expansion filled a larger enrollment target. A larger cohort provides more observations, but the reviewed announcement does not quantify a statistical-power increase or establish that treatment works across particular breeds or health backgrounds. Enrollment size alone cannot show whether LOY-002 is effective.
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See Loyal’s 1,000-dog expansion announcement and its STAY enrollment-completion update.
What is LOY-002?
LOY-002 is Loyal’s investigational daily flavored tablet for senior dogs. Loyal describes it as intended to address age-related metabolic dysfunction and extend healthy lifespan. These are the company’s stated aims, not demonstrated outcomes.
LOY-002 is being studied in STAY, Loyal’s pivotal efficacy study. The reviewed sources do not establish that the drug has delayed disease, improved quality of life, or extended dogs’ lives.
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How the STAY study works
Loyal describes STAY as a double-blinded, placebo-controlled study comparing lifespan, health, and quality of life in dogs given LOY-002 or placebo. Its current trial information says eligible dogs had to be at least 10 years old and weigh at least 14 pounds. Participants receive daily study medication, complete owner surveys, and attend repeated clinic visits.
Loyal says each participant has a 50% chance of receiving active drug and a 50% chance of receiving placebo. The study may last up to four years. STAY is fully enrolled, so owners cannot currently sign up through the study.
Lifespan refers to how long a dog lives; health and quality of life concern how the dog is doing during that time. The trial is intended to compare these outcomes, but its results have not been reported in the reviewed sources. See Loyal’s STAY trial information.
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Where LOY-002 stands with the FDA
In its January 2026 update, Loyal reported FDA acceptance of LOY-002’s Reasonable Expectation of Effectiveness (RXE) and Target Animal Safety (TAS) sections, with manufacturing work remaining. These are company-reported regulatory milestones, not approval to market the drug.
Acceptance of those sections does not establish that STAY succeeded or that LOY-002 extends lifespan. The reviewed source set does not include an FDA-hosted LOY-002 status page, and no STAY efficacy result was identified.
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1Fix the driver behind crashes, sound loss and screen glitches2Clear out junk files and repair common Windows errors3Scan for outdated or missing drivers - takes under a minuteWhat the 1,300-dog milestone does—and does not—mean
| Milestone or status | What the reviewed sources say | What it does not show |
|---|---|---|
| Original enrollment target | Loyal said it reached its target of 1,000 dogs in April 2025. | It is not a treatment result. |
| Expanded target | Loyal said it would recruit up to 300 additional dogs; its current page reports 1,300 enrolled across 70 veterinary practices. | The enrollment total does not prove effectiveness or quantify a treatment benefit. |
| Regulatory sections | Loyal reported FDA acceptance of RXE and TAS, with manufacturing work remaining in its January 2026 update. | Section acceptance is not marketing approval. |
| STAY outcomes | The study is designed to compare lifespan, health, and quality of life. | No result identified in the reviewed sources establishes lifespan extension. |
Can owners buy LOY-002 or join STAY?
STAY is fully enrolled, so it is not currently open for new participants according to Loyal’s trial page. The study medication is part of a blinded research study, and participants may receive placebo.
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The reviewed sources do not establish that LOY-002 is approved or available to buy. Avoid products or sellers claiming to offer the investigational drug, and ask a veterinarian about care for an older dog.
What owners can do for a senior dog now
While STAY’s results remain unknown, owners can discuss practical care with their veterinarian. Ask about appropriate weight and nutrition, screening based on the dog’s age and health, pain or mobility changes, dental health, and quality-of-life concerns. Do not treat LOY-002’s proposed benefits as established or make major diet or medication changes without veterinary guidance.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Frequently Asked Questions
What does the 1,300-dog expansion mean?
Loyal increased STAY’s original 1,000-dog target by up to 300 participants in 2025. Its current trial page reports 1,300 dogs enrolled across 70 veterinary practices.
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- Contains Glucosamine for Dogs: Cosequin contains glucosamine hydrochloride (FCHG49) and sodium chondroitin sulfate (TRH122), plus methylsulfonylmethane (MSM). This unique combination of ingredients supports healthy joints
- For Any Breed or Size: Whether you have a young or senior dog, a small or large breed, Cosequin helps support their joint health
- Tasty Chews for Daily Use: Cosequin comes in a tasty chewable tablet, making daily administration easy and convenient
- Exceptional Quality: Cosequin is backed by science, undergoing thorough quality inspections to ensure your dog receives a safe, high-quality product. It is manufactured in the United States with globally sourced ingredients
Does the larger trial prove LOY-002 works?
No. Enrollment is a study milestone, not an efficacy result. The reviewed sources do not report a STAY result showing that LOY-002 extends lifespan.
Is LOY-002 approved?
The reviewed sources do not establish marketing approval. Loyal reported FDA acceptance of the RXE and TAS sections, with manufacturing work remaining in its January 2026 update. Those milestones are not approval.
Can my senior dog still join STAY?
No, according to Loyal’s current trial page, which describes STAY as fully enrolled. The page says eligibility required dogs to be at least 10 years old and weigh at least 14 pounds.
Could LOY-002 give dogs a specific number of extra years?
No number has been established in the reviewed sources. The study’s effectiveness results have not been reported there.
The Bottom Line
STAY reached a larger enrollment target than Loyal originally planned, and the company reports that 1,300 dogs across 70 veterinary practices are enrolled. That makes the study a substantial milestone, but it is not evidence that LOY-002 extends lifespan. Loyal has reported FDA acceptance of two technical sections, with manufacturing work remaining; neither that progress nor enrollment means the drug is approved.
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