Initially studied decades ago. Interest in the compound continues to expand.
Semax
Semax is a synthetic peptide derived from a fragment of adrenocorticotropic hormone, the ACTH(4-10) sequence, with a proline-glycine-proline tail added to slow degradation. Critically, the fragment retains the behavioural activity attributed to ACTH without its hormonal activity.
That separation is the point. ACTH is a stress hormone with wide systemic effects; isolating a fragment that acts on the nervous system while leaving the endocrine axis alone was a deliberate piece of molecular editing. Semax is a case study in taking a large hormone apart to find the useful piece.
The literature examines effects on brain-derived neurotrophic factor expression, cerebral ischaemia models, and attention and memory endpoints in rodent studies, alongside clinical use within the Russian healthcare system where it has been registered for several decades. As with Selank, independent verification outside those groups is limited.