Semax
Medium EvidenceA synthetic peptide derived from ACTH, studied for cognitive enhancement and neuroprotective effects.
What It Is
Semax is a heptapeptide, a synthetic analog of ACTH(4-10), developed in Russia. It has been studied for cognitive enhancement, neuroprotection, and its effects on BDNF (brain-derived neurotrophic factor). Registered as a medication in Russia and several CIS countries, it is used for cognitive disorders, stroke recovery, and optic nerve diseases. In 2026, laboratory programs are examining how Semax interacts at the receptor level — particularly within the BDNF-TrkB signaling system — with improved analytical instrumentation and better understanding of receptor pharmacology making preclinical research more precise and reproducible. Advances in nasal delivery mechanisms have also improved bioavailability studies. Semax is scheduled for PCAC review on July 24, 2026, for potential inclusion on the FDA 503A Bulks List, which would allow legal compounding by U.S. pharmacies with a prescription. On February 27, 2026, HHS announced Semax would move from Category 2 (banned from compounding) back to Category 1 (legal through compounding pharmacies with a prescription).
Regulatory Status
Moved from Category 2 back to Category 1 per HHS announcement February 27, 2026. FDA PCAC will review Semax (free base and acetate) on July 24, 2026 for potential 503A Bulks List inclusion. Public comment docket FDA-2025-N-6895 open until July 22, 2026.
Effective: February 2026
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Commonly Discussed Benefits
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Safety & Cautions
- Approved in Russia/Ukraine but not FDA-approved
- PCAC review scheduled July 24, 2026 for potential 503A Bulks List addition; proposed indications include cerebral ischemia, migraine, and trigeminal neuralgia
- Western clinical trial data is limited
- May affect hormone levels via ACTH pathway
Comparisons
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Citations
- [1] Ashmarin IP. et al. — Semax: a regulatory peptide analogue. Neurosci Behav Physiol. 2007 PubMed
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