ATX-304 (laboratory code O-304) is a small-molecule “pan-AMPK activator,” meaning it turns on AMP-activated protein kinase, a cellular fuel-sensing enzyme, across its different tissue-specific forms. It is not a peptide. Discovered by the Swedish biotech Betagenon AB and now controlled by Amplifier Therapeutics (a Cambrian BioPharma subsidiary), it is a genuinely clinical-stage compound: a 2018 peer-reviewed paper reported both mouse data and a small proof-of-concept human trial in people with type 2 diabetes, making it one of the few compounds discussed on this site with real, published early-phase human results rather than only animal or anecdotal evidence.
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Research snapshot
| Category | Current information |
|---|---|
| Peptide category | Small-molecule pan-AMPK activator (not a peptide) |
| Primary research interest | Type 2 diabetes glucose control; microvascular perfusion; broader metabolic and age-related disease (company-stated) |
| Highest available evidence | Published human clinical trial (small Phase IIa proof-of-concept) |
| Human research available | Yes, limited — one small Phase IIa trial in type 2 diabetes patients on metformin, reported in a 2018 peer-reviewed paper |
| Development status | Investigational; held by Amplifier Therapeutics (Cambrian BioPharma), originally developed at Betagenon AB; a stated Phase Ib plan could not be confirmed as active on ClinicalTrials.gov |
| Regulatory status | Not approved anywhere |
| Last reviewed | September 27, 2026 |
Technical identity
| Technical property | Information |
|---|---|
| Primary name | ATX-304 |
| Alternative names | O-304 (original development/laboratory code, used in the 2018 published paper and by chemical suppliers); O304; ATX304 (misspelling) |
| Peptide sequence | Not applicable — ATX-304 (O-304) is a non-peptide small molecule, with no amino-acid sequence |
| Amino-acid length | Not applicable |
| Molecular formula | C16H11Cl2N3O2S |
| Molecular weight | Approximately 380.25 g/mol |
| CAS Registry Number | 1261289-04-6 |
| PubChem CID | Not reliably established; located via a chemical-supplier database (Cayman Chemical), not confirmed against an authoritative PubChem record |
| Chemical modifications | Not applicable |
| Peptide class | Not a peptide — synthetic pan-AMPK (AMP-activated protein kinase) activator |
| Primary biological target | AMP-activated protein kinase (AMPK), across its major tissue forms |
| Developer or originator | Originally developed at Betagenon AB; now held by Amplifier Therapeutics, a subsidiary of Cambrian BioPharma |
| Development status | Investigational; Phase IIa proof-of-concept human trial published (2018); no confirmed active later-phase trial located |
What it is
ATX-304 is a synthetic small molecule, not an amino acid chain, developed by researchers at Umeå University and the company they founded, Betagenon AB, in Umeå, Sweden. It was designed as a “pan-AMPK activator,” meaning it is intended to activate all the major tissue-specific complexes of AMP-activated protein kinase (AMPK) rather than a single isoform-selective one. AMPK is the enzyme that switches on when a cell senses falling energy stores, the same sensor engaged by exercise and caloric restriction, and it is a long-standing target for metabolic disease drug discovery because activating it can increase glucose uptake and fat oxidation without the person actually exercising.
The compound was first described in the peer-reviewed literature by Steneberg and colleagues in 2018, in the journal JCI Insight, under the code name O-304. That paper reported that O-304 improved glucose homeostasis and microvascular perfusion in diet-induced obese mice and, notably, in a proof-of-concept Phase IIa clinical trial the same paper describes in people with type 2 diabetes already taking metformin. This is unusual for a compound of this type: most of the research-chemical AMPK activators circulating online have never been tested in a person. ATX-304 has, at least in that one small trial.
In 2023, Cambrian BioPharma launched a subsidiary, Amplifier Therapeutics, specifically to advance ATX-304 (and the broader Betagenon AMPK-activator chemistry) toward the clinic, reportedly in a licensing and asset transaction described in industry press as worth roughly $26 million. Amplifier’s stated near-term plan, per that press coverage, was a Phase Ib proof-of-concept study in patients with metabolic dysfunction, aimed eventually at a broad set of age-related metabolic and cardiovascular conditions. This site could not independently locate that Phase Ib trial, or any later-stage ATX-304 trial, on ClinicalTrials.gov as of the date this entry was checked, so the trial’s exact design, dosing, and current status should be treated as company-announced rather than independently confirmed against a public registry.
Because ATX-304 is a relatively obscure, still-emerging compound, a fair amount of what circulates about it online comes from research-chemical vendor pages and enthusiast blogs rather than the original science. Several of those secondary sources describe newer trial names (for example, a “TELLUS” Phase IIa label, or planned “REWIRE” Phase 2 studies) and a 2026 conference dataset that this site could not verify against a primary registry, company filing, or peer-reviewed publication. Those specific claims are described later in this entry as unverified, not as established fact.
How does it work?
Plain-English explanation
Think of AMPK as a cell’s low-fuel warning light. When it switches on, whether because of exercise, fasting, or a drug, the cell responds by pulling in more glucose, burning more fat, and generally acting as though it needs to conserve and generate energy. ATX-304 is designed to switch that warning light on directly, mimicking part of what exercise does to metabolism, without the person actually having to exercise.
Technical explanation
AMPK is a heterotrimeric enzyme complex normally activated when the cellular ADP:ATP and AMP:ATP ratios rise, reflecting energy depletion, through phosphorylation at threonine-172 on its catalytic alpha subunit. According to the original characterization work, ATX-304 activates AMPK broadly across its different subunit combinations (“pan” activation) rather than a single tissue-restricted isoform, and vendor and secondary chemistry sources describe its proposed mechanism as protecting the phosphorylated, active form of AMPK from being switched back off by the phosphatase PP2C, rather than directly mimicking AMP itself; this site was not able to independently verify that specific phosphatase-protection mechanism against a primary peer-reviewed source and flags it as reported by secondary chemistry-vendor literature rather than confirmed here. In the peer-reviewed 2018 study, O-304 increased skeletal muscle glucose uptake, reduced pancreatic beta-cell stress, improved microvascular perfusion, and lowered blood pressure in both diet-induced obese mice and in the small human trial, while activating cardiac AMPK and improving left ventricular stroke volume in mice without increasing heart weight in mice or rats, an important finding given that some other cardiac-hypertrophy pathways intersect with AMPK signaling.
Potential benefits and research applications
Improved glucose control in type 2 diabetes (human evidence, early-phase)
What is being investigated: whether pan-AMPK activation can lower blood glucose and improve insulin resistance in people with type 2 diabetes already on standard therapy. How the effect might occur: AMPK activation increases insulin-independent glucose uptake in skeletal muscle. Evidence: the 2018 Steneberg et al. paper reports a proof-of-concept Phase IIa trial in type 2 diabetes patients on metformin in which O-304 reduced fasting plasma glucose and HOMA-IR (a standard insulin-resistance index). Strength: is genuine early-phase human clinical evidence, published in a peer-reviewed journal, which is uncommon for a compound this obscure. Limitation: described by its own authors as a small, proof-of-concept study; exact enrollment, dosing, and duration for the human arm were not fully itemized in the abstract-level information available to this entry, and no later, larger confirmatory human trial result was located.
Improved microvascular perfusion and blood pressure (mixed animal and early human evidence)
What is being investigated: whether AMPK activation improves small-vessel blood flow and blood pressure, relevant to the microvascular complications of diabetes. How the effect might occur: AMPK signaling in vascular endothelium and smooth muscle affecting vasodilation and vascular tone. Evidence: reported in both diet-induced obese mice and the same human T2D trial in the 2018 paper. Strength: has been shown in a peer-reviewed paper combining animal and human data. Limitation: the human component was small and proof-of-concept; microvascular perfusion outcomes are harder to generalize from a small trial than a simple lab value.
Cardiac protection without hypertrophy (animal evidence only)
What is being investigated: whether AMPK activation can improve cardiac glucose handling and function the way exercise does, without the pathological heart enlargement seen with some other cardiac stimuli. How the effect might occur: AMPK activation in cardiac tissue increasing glucose uptake and reducing glycogen accumulation. Evidence: shown in mice and rats in the 2018 paper, including improved left ventricular stroke volume and no increase in heart weight. Strength: has been shown in a controlled animal study from a peer-reviewed source. Limitation: not established in a human cardiac outcomes trial; this remains an animal finding.
Broader metabolic and age-related disease applications (company-stated, largely unverified)
What is being investigated: whether pan-AMPK activation more broadly benefits cardiovascular disease, kidney disease, and other age-related metabolic conditions, per Amplifier Therapeutics’ publicly stated development rationale. How the effect might occur: AMPK sits at the intersection of several metabolic and aging-related signaling pathways, giving this idea general biological plausibility. Evidence: is being investigated, according to industry press describing the company’s stated intentions; this site did not locate a completed trial or published result testing these broader indications specifically. Strength: has not been established for any of these additional indications. Limitation: this is a development-stage company’s stated future direction, not a finding.
What dosage information circulates?
Figures in this section summarize amounts and schedules reported in published research or circulating online. Their inclusion documents what is reported and does not establish that a regimen is verified, safe, effective, or appropriate.
| Reported use or research objective | Route reported | Amount reported | Frequency reported | Reported duration | Evidence or source category |
|---|---|---|---|---|---|
| Type 2 diabetes glucose control (Phase IIa proof-of-concept) | Not obtainable from the abstract-level source reviewed | Not obtainable from the abstract-level source reviewed | Not obtainable from the abstract-level source reviewed | Not obtainable from the abstract-level source reviewed | Published human clinical trial (Steneberg et al. 2018, JCI Insight) |
| Diet-induced obesity and cardiac safety (mouse and rat) | Not obtainable from the abstract-level source reviewed | Not obtainable from the abstract-level source reviewed; not reproduced here to avoid mis-stating an unverified figure | Not obtainable from the abstract-level source reviewed | Not obtainable from the abstract-level source reviewed | Published animal research (same 2018 paper) |
| General oral “research compound” framing | Oral | Informal daily amounts in the milligram range, sometimes framed against the 2018 published trial | Not established | Not established | Widely repeated online, but its original source could not be verified |
Amounts studied in human research
No established or reliably sourced human dosing information was identified. The 2018 peer-reviewed paper reports that a Phase IIa proof-of-concept trial was conducted in people with type 2 diabetes on metformin, but the specific oral dose, dosing frequency, and treatment duration used in that human arm were not obtainable from the abstract-level source reviewed for this entry, and this site did not locate the full trial protocol or a trial registry record confirming those details.
Amounts studied in animal research
The 2018 paper studied O-304 in diet-induced obese mice and in rats for cardiac safety assessment; specific milligram-per-kilogram dosing figures for those animal experiments were not obtainable from the abstract-level source reviewed here and are not reproduced in this entry to avoid mis-stating a number this site could not directly verify against the full paper.
Practitioner and community-reported protocols
Widely repeated online, but its original source could not be verified: research-chemical vendor sites selling ATX-304/O-304 as an oral “research compound” describe informal daily oral amounts in the milligram range, sometimes framed against the 2018 published trial, but this site could not trace any specific circulating figure back to a named clinical source, and these are unregulated research-chemical listings, not sourced medical guidance. No practitioner-reported (clinical or telehealth) protocol was identified for this compound.
What circulates E5
Widely repeated online, but its original source could not be verified: research-chemical vendor sites selling ATX-304 (O-304) as an oral "research compound" describe informal daily oral amounts in the milligram range, sometimes framed against the 2018 published human trial. This site could not trace any specific circulating figure back to a named clinical source, and these are unregulated research-chemical listings, not sourced medical guidance.
No practitioner-reported (clinical or telehealth) protocol was identified for this compound, and no single milligram figure was consistent or specific enough across sources to responsibly present as a reported protocol here.
Recorded as an observation about what is published elsewhere. No figure here is a dose, a protocol, or a recommendation, and nothing in this section is evidence that any amount is safe or effective.
Side effects, risks, and limitations
The 2018 paper describes O-304 as generally well tolerated in the mouse and small human proof-of-concept work reported, including the notable finding that it did not increase heart weight in mice or rats despite activating cardiac AMPK, but this site did not locate a detailed, itemized adverse-event table from a larger or longer human trial. Because ATX-304 is a novel chemical entity still in early clinical development, its longer-term human safety profile, drug interactions, and effects in populations beyond the small, metformin-treated type 2 diabetes group studied in 2018 are not established. Material sold online as a “research compound” is unregulated, has no confirmed purity or identity testing behind any individual listing, and using it outside a supervised clinical trial carries risks that have not been characterized in any published human safety dataset.
Regulatory and developmental status
ATX-304/O-304 is an investigational compound. It is not FDA-approved, or approved by any other regulator identified in this research, for any indication. It has advanced further than most compounds discussed on this site: a peer-reviewed 2018 paper reports both mouse data and a completed small human Phase IIa proof-of-concept trial. Amplifier Therapeutics, a subsidiary of Cambrian BioPharma, holds rights to the compound (via a reported 2023 transaction with Betagenon AB) and has publicly described plans for further clinical development, including a Phase Ib study, though this site could not confirm a currently active or completed later-phase trial on ClinicalTrials.gov as of the date checked. Additional claims found only on secondary vendor or blog sources, including specific newer trial names and a 2026 conference dataset, could not be verified against a primary source and are not treated as established in this entry.
Frequently asked questions
What is ATX-304?
A small-molecule pan-AMPK activator, developed by Betagenon AB and now held by Amplifier Therapeutics, studied for type 2 diabetes and broader metabolic disease. It is not a peptide.
How does it work?
It activates AMP-activated protein kinase (AMPK), a cellular energy-sensing enzyme, across its major tissue forms, mimicking part of the metabolic signal normally triggered by exercise or fasting.
What dosage has been studied?
No established or reliably sourced human dosing information was identified from the sources available to this entry. A small human Phase IIa trial in type 2 diabetes patients on metformin has been published, but the specific dose used was not obtainable from the abstract-level source reviewed here.
Has it been studied in humans?
Yes, in a small, proof-of-concept Phase IIa trial reported in a 2018 peer-reviewed paper, in people with type 2 diabetes already on metformin. This is genuine, if limited, human clinical evidence, which is unusual for a compound this obscure.
Is ATX-304 the same as O-304?
Yes. O-304 is the original laboratory/development code used in the 2018 peer-reviewed paper and by chemical suppliers; ATX-304 is the name used by Amplifier Therapeutics as the compound advances toward further clinical development.
Is it approved for any use?
No. It remains an investigational compound with no confirmed regulatory approval anywhere.
What is the developer’s stated future plan for it?
Industry press describes Amplifier Therapeutics’ stated intent to advance ATX-304 through further clinical trials for metabolic and age-related disease, including a Phase Ib study; this site could not independently confirm the current status of that trial on a public registry.
What remains unknown?
The specific human dose and regimen used in the published 2018 trial, the current status and design of any newer company-run trial, whether the broader age-related-disease applications the developer has proposed will be tested, and the compound’s long-term human safety profile.
Bottom line
ATX-304 (O-304) is a real, clinical-stage pan-AMPK activator with a genuinely published early human proof-of-concept dataset in type 2 diabetes, which sets it apart from most obscure research chemicals. But the human evidence is limited to one small trial described in a 2018 paper, the exact dosing used there could not be confirmed from the sources reviewed here, and several more recent claims about newer trials circulating on vendor and enthusiast sites could not be verified against a primary source. It is not approved for any use, and no dose has been established as safe or effective for people outside a supervised clinical trial.
