Inside our first study: follistatin gene therapy for aging dogs

A Single Shot Against Aging: Inside Dog Years' Follistatin Gene Therapy Study

For most of veterinary medicine's history, the diseases that slow our dogs down in their final years have been treated one symptom at a time. A pill for the pain. An injection for the joints. A supplement that may or may not help. What none of these touch is the underlying biology of decline itself. Dog Years is built around a different question: what if a single treatment could address the root cause, and last for a year?

The science, briefly

Follistatin is a protein the body already makes. It rises naturally with exercise and peaks in youth. Its job is to put the brakes on two other proteins — myostatin, which limits muscle growth, and activin, which drives inflammation. Turn up follistatin, and you get more muscle and less inflammation at the same time. For a disease like osteoarthritis, where joints are both inflamed and starved of the muscular support that protects them, hitting both levers at once is unusually well-suited to the problem.

The challenge has always been delivery. Injected follistatin clears the body within hours. Dog Years' approach instead uses a gene therapy -  a minicircle plasmid - that instructs the dog's own cells to produce follistatin for roughly a year from one intramuscular shot. No daily medication, no repeat visits. One administration, sustained effect.

Why this isn't starting from zero

This is where the program earns a second look. The same therapy has already been through a human Phase 1 trial of 43 adults, which reported no serious adverse events alongside measurable gains in lean mass, reductions in body fat, and a roughly seven-year drop in one marker of biological age. A single severely arthritic dog who received the vector showed a dramatic, months-long reduction in pain behavior. The biology is also supported by mouse models of osteoarthritis. The point of the canine study is not to discover whether follistatin works in principle — it's to translate an established safety profile into a real veterinary indication.

What the study actually does

Thirty to fifty dogs — elderly, or already diagnosed with osteoarthritis or a related degenerative condition — will be enrolled. The design uses a delayed-start control: one group is treated immediately, the other after a three-month observation window. The elegance here is ethical as much as scientific. Every dog eventually receives the therapy, so no owner is asked to leave their animal untreated, yet the staggered start still produces clean control data.

Dosing escalates carefully in three tiers, advancing only after safety is confirmed at the lower dose. Over twelve months, the team measures the things that matter to a dog's life and to a regulator: safety bloodwork, gait analysis on a pressure-sensitive platform, veterinary and owner-reported pain scores, radiographic disease progression, and — for the longevity-minded — inflammatory markers, body composition, and epigenetic age.

Why investors should care

The strategic insight is regulatory, and it's sharp. Plenty of groups want to bring follistatin gene therapy to humans, but they hit a wall: regulators don't recognize "aging" or "frailty" as a disease you can treat. Arthritis, however, is a real, approvable indication. By proving follistatin treats canine degenerative disease first, Dog Years opens a legitimate regulatory pathway — in a market (companion animals) with faster timelines, lower costs, and genuine unmet need, since today's only disease-modifying option for canine osteoarthritis works by a mechanism nobody fully understands.

It's a rare alignment: a near-term commercial product, a real clinical need, and a stepping stone toward something much larger in human medicine. For a DeSci portfolio, it's the unusual case where the science, the ethics, and the business model all point the same direction.

The bigger picture

The founder's path here runs through frontier self-experimentation and the human trial that preceded this work, which is part of why the canine program moves with conviction rather than caution-for-its-own-sake. But the study itself is sober: controlled, staged, ethically designed, and measuring what it claims to measure.

If it succeeds, the payoff isn't only longer, more comfortable lives for aging dogs — meaningful as that is. It's a validated platform and a paved regulatory road, with our companion animals leading the way toward therapies that may one day extend healthspan in humans, too.

Source: Patterson W, Rossner RJ, Garuda R, Davis M, Terry GC. Plasmid delivery of follistatin gene therapy safely improves body composition and lowers extrinsic epigenetic age in sex- and age-diverse adult human subjects. Preprint, March 11, 2024. Read the preprint (PDF)