Semax is a synthetic heptapeptide built from ACTH(4–10) — a seven-residue fragment of adrenocorticotropic hormone — with a Pro-Gly-Pro tripeptide attached at the C-terminus.
Why the Pro-Gly-Pro matters
The added tripeptide is the design feature worth understanding. Short peptides are rapidly cleaved by peptidases; the Pro-Gly-Pro extension substantially slows enzymatic degradation, extending half-life relative to the bare ACTH fragment.
Critically, the ACTH(4–10) fragment retains the neurotropic properties associated with the parent hormone without its corticotropic activity — it does not drive cortisol release the way full ACTH does. Separating those two effects is the point of the molecule.
Mechanism
The most reported action is modulation of brain-derived neurotrophic factor (BDNF) and its receptor TrkB. Preclinical work also describes effects on the dopaminergic and serotonergic systems and on expression of genes associated with neuroprotection and neuroplasticity.
Research status
Semax has a substantial Russian clinical literature and is registered there for certain indications. Western peer-reviewed replication is comparatively sparse, and much of the primary literature is not in English — a genuine barrier to independent assessment rather than a minor detail.
Supplied lyophilised. See our reconstitution protocol for handling technique and diluent selection.
Every batch ships with a third-party certificate of analysis. View Semax and its current COA.
Research use only
Isla Longevity supplies this compound for laboratory research use only. It is not approved by the FDA for human or veterinary use and is not for human consumption. This article summarises published research and is not medical guidance.
