HomeFull speed ahead. Keep track of advancements in every frontier

TheTechno Optimist.

LOY-001 / LOY-003Loyal—LOY-002Loyal—LOY-002Loyal—

LOY-002

by LoyalUS

DeployStage 4 of 5

FDA accepted the effectiveness and safety sections; manufacturing review pending before possible approval.

Updated 11 Feb 2026Checked 25 Sep0 updates this week

Milestones

Next · Manufacturing section accepted
  1. STAY main study launchesFeb 2024Complete.
  2. FDA accepts the 'should work' sectionFeb 2025Complete.
  3. Safety section accepted13 Jan 2026Complete.
  4. Manufacturing section acceptedNowCurrent milestone.
  5. Conditional approval and launchNot yet reached.
  6. STAY study resultsNot yet reached.

Most important updates

  • 11 Feb 2026
  • 13 Jan 2026
  • 14 Jul 2025
  • 14 Apr 2025
  • Feb 2025

Current obstacles

  • Manufacturing reviewMaking it at commercial scale must satisfy the FDA before it can be sold.
  • Could lose approvalConditional approval ends if STAY doesn't show dogs live longer.

Physics limits

  • Lifespan takes a lifetime to measureEven in dogs aged 10 and up, showing longer life needs years of follow-up and over 1,000 dogs, because deaths come slowly and vary widely between animals.
  • Calorie-restriction effects shrink in long-lived animalsEating less extends life by up to a few tens of percent in rodents, but two long rhesus-monkey studies disagreed on lifespan. Gains likely get smaller as lifespan grows.
  • Metabolic brakes have side effectsDialling down growth and energy signals can slow healing, weaken immunity and cost muscle, so the useful dose range is limited.

How it works

3 parts
A senior Labrador: LOY-002 is a daily pill for dogs 10 and older, aimed at the metabolism that slows with age
A senior Labrador: LOY-002 is a daily pill for dogs 10 and older, aimed at the metabolism that slows with agePhoto: Marek Ślusarczyk (Tupungato) · CC BY 3.0 (opens commons.wikimedia.org)
Target

Metabolism that slows with age

The pill aims to copy some effects of eating less, the best-proven way to extend life in animals.

Study

Pill vs placebo in pet dogs

Owners give the pill or a dummy; vets track health and survival over years.

Regulation

Three FDA sections

FDA must accept three technical sections: reasonable expectation of effectiveness, safety, and manufacturing, before conditional approval.

Spec sheet

SpecLOY-002
FormDaily oral pillR (reported)
Target populationDogs 10+ years, 14+ lbR (reported)
STAY study size1,000+ dogsR (reported)
STAY follow-up~4 yearsE (estimated)

R reported by the company · E our estimate

Update log

7 updates

Wed 11 Feb

  • Major: BlogFunding

Tue 13 Jan

  • Minor: PressRegulatory

Mon 14 Jul 2025

  • Major: BlogTest

Mon 14 Apr 2025

  • Minor: BlogTest

Feb 2025

  • Major: PressRegulatory

Thu 21 Mar 2024

  • Minor: BlogFunding

Tue 11 Apr 2023

  • Minor: BlogTest

About Loyal

The team behind LOY-002

Loyal

Lifespan drugs for dogs

San Francisco biotech founded by Celine Halioua making drugs to extend healthy life in dogs, aiming to be the first to win FDA approval for longer life. Its daily pill LOY-002 for senior dogs has two of three key FDA sections accepted.

  • Nov 2023: the FDA's vet center accepted that LOY-001 can reasonably be expected to work: a first for any lifespan drug.
  • Jan 2026: FDA accepted LOY-002's safety section; manufacturing is the last big section before conditional approval.
  • Conditional approval would allow sales while the STAY study of over 1,000 senior dogs continues.

loyal.com (opens loyal.com)Company profile →

Founded
20197 yrs
Headquarters
United States
Status
Private
Valuation
private
Raised
$67M2 rounds
Last round
Financing · $22MFeb 2025
Works in
LongevityPet longevity
Coverage
2 programs · 11 updateslatest 24d agochecked 25 Sep
People
Celine HaliouaFounder and CEO
Primer