PE-22-28
What the Research Says
PE-22-28, also called Mini-Spadin, is one of the more interesting early-stage molecules in this directory, and also one of the least tested. It is a very small synthetic peptide, seven amino acids long, built as a more stable and more potent version of a natural brain molecule called spadin. Its target is specific and unusual: a potassium channel called TREK-1 that sits in the middle of how the brain regulates mood.
What makes it worth a page is the mechanism, which is precise and genuinely novel, and what makes it a research entry rather than a practice one is the evidence, which so far is entirely in cells and animals. There are no human trials of PE-22-28. We lay out below what the science actually shows, and we are careful not to describe animal findings as if they were human results.
This page currently focuses on the research. The section on how we work with it in practice is being reviewed with Dr. Koniver and will be added once that is complete.
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What we've seen in practice
PE-22-28 has not yet been part of the clinical teaching we draw these practice notes from, so rather than fill this section with anything secondhand, we are leaving it open until we can capture Dr. Koniver's own perspective on whether and how it fits our work. The research below stands on its own in the meantime.
PE-22-28 at a glance
A synthetic 7-amino-acid peptide (Mini-Spadin), a more stable analog of the natural TREK-1 blocker spadin [1]
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Mood (an antidepressant-style mechanism) and, more speculatively, memory and neuroprotection [1, 2]
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Entirely preclinical: cell and rodent studies of TREK-1 blockade and antidepressant-like effects; no human trials [1, 2]
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By injection or intranasally in the research literature; poorly absorbed by mouth
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Sequence Gly-Val-Ser-Trp-Gly-Leu-Arg (GVSWGLR); formula C35H55N11O9, about 773.9 g/mol [4]
Not FDA-approved; an investigational research peptide with no established clinical pathway; treat as prohibited in sport (non-approved substance)
Being reviewed with Dr. Koniver. See the note above
Corrected chemistry: the source lists a sulfur-containing formula, but GVSWGLR has no sulfur. The correct formula is C35H55N11O9, about 773.9 g/mol.
Where PE-22-28 comes from
The starting point is a natural molecule called spadin. Your body makes spadin as a byproduct when it processes a receptor protein, and researchers found that spadin blocks a specific potassium channel in the brain called TREK-1. That turned out to matter, because blocking TREK-1 produces antidepressant-like effects in animals, and it appears to do so quickly, which is interesting given how slowly traditional antidepressants work.
Spadin itself is fragile and short-lived, so a French research group set out to build a better version. PE-22-28 is the result: the smallest fragment of spadin that still blocks TREK-1 well, re-engineered for more stability and stronger activity. It is a clean example of turning a natural signal into a more drug-like tool. The important caveat is that this whole story, so far, has played out in laboratories and animal models.
PE-22-28 sits in the TREK-1 potassium channel and blocks it, making certain neurons more active.
How PE-22-28 works
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PE-22-28's defining action is to block TREK-1, a potassium channel that helps set how excitable certain neurons are. Blocking it makes those neurons more active, and in animal models this produces antidepressant-like effects.[1]
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In animals, that TREK-1 blockade is linked to stronger serotonin signaling in the brain regions that regulate mood.[1]
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Preclinical work associates the pathway with more BDNF, new synaptic connections, and the birth of new neurons in the hippocampus, which is the basis for the memory interest.[1, 2]
A specific and interesting mechanism, and an honest early-stage evidence base [1,2].
What the research shows
The research on PE-22-28 is real, focused, and entirely preclinical. The foundational study designed the peptide and showed that, compared with natural spadin, it blocked the TREK-1 channel more effectively, lasted longer in the body, and produced stronger antidepressant-like effects in rodent models [1]. A later review from the same group placed PE-22-28 within the broader effort to treat depression by blocking TREK-1, and laid out both the promise and the distance still to travel[2]
Antidepressant mechanism
Rodent models; the design paper
Blocks TREK-1; antidepressant-like effects; better stability than spadin
Preclinical [1]
Mood-disorder application
Animal models; a mechanistic review
A novel, potentially fast-acting route for depression
Preclinical; no human trials [2]
Memory and neuroprotection
Preclinical association only
Links to BDNF, new synapses, hippocampal neurogenesis in animals
Early, mechanism-level [1]
Human clinical use
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No completed human trials
How strong is the evidence
Every tier here is animal or laboratory. There is no human evidence yet.
The honest answer is that PE-22-28's safety in people is essentially unknown, because there are no completed human trials. Animal studies report that it was well tolerated at the doses used, but that does not carry over directly to humans, and it is not a basis for treating it as safe in people.
There is also a mechanism-specific reason for caution. PE-22-28 works on a brain potassium channel that helps control how easily neurons fire, and that kind of channel has links to seizure threshold. Until there is human data, caution is warranted in anyone with a seizure disorder or taking neurological or psychiatric medications. As with any unapproved, untested compound, it should be avoided in pregnancy and breastfeeding and considered only under qualified medical oversight, not as a self-directed experiment.
Regulatory status
Regulatory information current as of 12 August 2026. This is a summary, not legal or medical advice, and status can change.
As a medicine
worldwide
Not approved anywhere; an investigational research peptide.
United States
Not FDA-approved. An obscure research compound with no established clinical or compounding pathway; not part of the 2023 or 2026 compounding lists. Offered only as research material of uncertain quality.
Sport (WADA)
TREAT AS PROHIBITED
Not individually named, but as a substance with no approval for human use it falls under non-approved substances, prohibited at all times. Verify.
Everywhere else
Because it is unapproved and unregulated, source quality and purity cannot be assured.
Regulatory information current as of 12 August 2026. Verify status at publication.
Common questions
It is a small synthetic peptide (also called Mini-Spadin) built as a more stable version of spadin, a natural molecule that blocks a brain potassium channel called TREK-1. Blocking that channel produces antidepressant-like effects in animals [1].
No. All of the research on PE-22-28 is in cells and animals. There are no completed human clinical trials, so its benefits and risks in people have not been established[1, 2]
Mainly as a fast-acting antidepressant mechanism, and more speculatively for memory and neuroprotection, based on animal work linking it to neuroplasticity [1,2].
Its safety in people is unknown because it has not been tested in human trials. There is also a specific reason for caution given its action on a brain channel linked to seizure threshold.
No. As a non-approved substance it should be treated as prohibited at all times in WADA-regulated sport.
Related peptides
References
- Djillani A, Pietri M, Moreno S, Heurteaux C, Mazella J, Borsotto M. Shortened Spadin Analogs Display Better TREK-1 Inhibition, In Vivo Stability and Antidepressant Activity. Front Pharmacol. 2017;8:643. PMID 28955242.
- Djillani A, Pietri M, Mazella J, Heurteaux C, Borsotto M. Fighting against depression with TREK-1 blockers: Past and future. A focus on spadin. Pharmacol Ther. 2019;194:185-198. PMID 30291907.
- Mazella J, Heurteaux C, and colleagues. The spadin and TREK-1 antidepressant research program (Institut de Pharmacologie Moleculaire et Cellulaire, CNRS, France).
- PE-22-28 chemistry: sequence Gly-Val-Ser-Trp-Gly-Leu-Arg (GVSWGLR); molecular formula C35H55N11O9, about 773.9 g/mol; CAS 1801959-12-5 (formula recomputed from the sequence).
This page is for informational and educational purposes and does not constitute medical advice, diagnosis, or treatment. PE-22-28 is an investigational research peptide that is not approved by the FDA or any national health authority for any use, has not been tested in completed human clinical trials, and should be treated as prohibited in competitive sport. Nothing here is a substitute for consultation with a qualified healthcare provider.
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