O-304 (ATX-304)

Key points

• O-304 (also called ATX-304) is a small molecule that activates AMPK, an enzyme that senses and manages cell energy.
• It is studied for diabetes, metabolism and blood flow.
• Testing is at an early stage, with limited human data.
• It is not a licensed medicine in the UK and is sold only for research use.

Quick facts

What it is

AMPK activator (small molecule, not a peptide)

Studied for

Diabetes, metabolism, circulation

UK status

Not a licensed medicine; sold for research use

Human evidence

Limited and early

In sport

Metabolic modulators are prohibited

How it works

AMPK acts like a fuel gauge for the cell. When it is switched on, cells burn more fat and take up more glucose, the sort of changes that also happen with exercise. O-304 activates AMPK directly, which is why it is studied for metabolism and the circulation. How well this works, and how safely, in people is still being explored.

What the evidence shows

Most of the evidence is from animal and early studies. Human data is limited, and there is no established dose or clear long term safety picture. It remains an investigational compound rather than a proven treatment.

What it does not settle

• Human evidence is limited and early.
• There is no established dose or long term safety data.
• Benefits for metabolism or circulation are not yet proven in people.

Side effects

Less common but serious

• Its safety in sustained human use is not established.
• Because there is no licensed product, the dose, purity and contents of material bought online cannot be verified.

Report any suspected side effect through the MHRA Yellow Card scheme.

UK legal status and access

O-304 has no UK marketing authorisation, so it is not a licensed medicine and is not offered by registered clinics or pharmacies. It is sold online as a research chemical. Metabolic modulators of this kind are also prohibited in sport.

Common questions