Semax
Semax was developed in Russia and is used there for indications including stroke, transient ischemic attack and cognitive/memory disorders; it was added to Russia's government-approved list of vital and essential drugs in December 2011. Outside Russia and some CIS countries it has not been evaluated, approved or marketed, and the Western-quality evidence base remains limited and largely preclinical.
Mechanism
Semax is reported to rapidly elevate BDNF and its TrkB receptor in the rat hippocampus (Dolotov et al., 2006) and to activate neurotrophin gene transcription, and to modulate dopaminergic/serotonergic systems; it may also interact with melanocortin (MC4/MC5) receptors. Primary sources note the precise mechanism of action in humans is not established, and the evidence is predominantly preclinical and Russian clinical work.
Regulatory Status by Region
- United States (FDA)Not FDA-approved; unscheduled. Historically placed on the FDA 503A 'Category 2' bulk drug substances list (significant safety concerns) restricting compounding; part of ongoing 2026 FDA compounding review.
- Australia (TGA)Not approved by the TGA and not on the ARTG; no registered therapeutic product.
- European Union (EMA)No EMA marketing authorisation; not an approved medicine in the EU.
- WADANot listed by name; because it lacks approval by major (stringent) regulatory authorities, it is generally treated as captured by the S0 'Non-Approved Substances' category, prohibited at all times. Athletes should treat it as prohibited.
Key Studies
- Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus (Dolotov OV, et al. Brain Res. 2006 Oct 30;1117(1):54-60. PMID: 16996037.)
- Neurotrophin gene expression in rat brain under the action of Semax, an analogue of ACTH(4-10) (Shadrina M, et al. Neurosci Lett. 2007. PMID: 17353092.)
- Semax and Pro-Gly-Pro Activate the Transcription of Neurotrophins and Their Receptor Genes after Cerebral Ischemia (review/mechanistic) (PMC11498467.)