Semax and Selank compared: chemistry, targets and regulatory records
Semax and Selank are both heptapeptides ending in Pro-Gly-Pro. Semax is an analogue of ACTH(4-10) and Selank an analogue of the tetrapeptide tuftsin.
Research-use information. This page summarises published literature and regulator records. It is not guidance for use, not medical advice, and not a statement that any material is suitable for use in people or animals.
How do Semax and Selank differ on the facts?
| Fact | Semax | Selank |
|---|---|---|
| Class | Heptapeptide, ACTH(4-10) analogue | Heptapeptide, tuftsin analogue |
| Length | 7 residues | 7 residues |
| Molecular formula | C37H51N9O10S | C33H57N11O9 |
| Average molecular weight | 813.9 g/mol | 751.9 g/mol |
| Receptor or pathway background | None named in the cited studies | None named in the cited studies |
| FDA (Drugs@FDA) | No application listed | No application listed |
| EMA (centrally authorised) | No centrally authorised medicine listed | No centrally authorised medicine listed |
| MHRA (Products) | No product document found | No product document found |
| WADA 2026 list | Not named | Not named |
| Studies in our library | 3 | 4 |
| PubMed records for the search terms | 155 | 126 |
| Registered studies (ClinicalTrials.gov) | 0 | 2 |
Data dates: chemistry checked against PubChem 2026-10-05; regulatory records 2026-10-05; WADA list 2026-10-05; PubMed counts 2026-10-05.
What do the cited papers say differs between Semax and Selank?
- The parent peptides differ: Semax derives from ACTH(4-10) (Met-Glu-His-Phe plus Pro-Gly-Pro) and Selank from tuftsin (Thr-Lys-Pro-Arg plus Pro-Gly-Pro), from the catalog sequences.[1],[4]
- Most published studies on both are rodent or cell studies; one imaging study measured resting-state connectivity in 52 healthy participants for both peptides.[2]
- Both were identified by analytical methods in seized pharmaceutical preparations.[3]
Nothing on this page ranks one compound above the other or states what either does for a person.
Which studies are cited on this page?
[1] Kolbaev SN, Sharonova IN, Skrebitsky VG. The Effect of Peptide Semax, an ACTH(4-10) Analogue, on Intracellular Calcium Dynamics in Rat Brain Neurons. Bull Exp Biol Med. 2025;179:416-420.
Measured intracellular calcium dynamics in rat hippocampal and cerebellar slices exposed to Semax.
[2] Panikratova YR, Lebedeva IS, Sokolov OY, Rumshiskaya AD, Kupriyanov DA, Kost NV, et al.. Functional Connectomic Approach to Studying Selank and Semax Effects. Dokl Biol Sci. 2020;490:9-11.
Measured whole-brain resting-state functional connectivity in 52 healthy participants for Selank and Semax.
[3] Vanhee C, Francotte A, Janvier S, Deconinck E. The occurrence of putative cognitive enhancing research peptides in seized pharmaceutical preparations: An incentive for controlling agencies to prepare for future encounters of the kind. Drug Test Anal. 2020;12:371-381.
Identification of Selank and Semax in seized pharmaceutical preparations by analytical methods. The authors state that neither has completed clinical trials, to their knowledge.
[4] Kolik LG, Nadorova AV, Antipova TA, Kruglov SV, Kudrin VS, Durnev AD. Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats. Bull Exp Biol Med. 2019;167:641-644.
Measured object-recognition memory and BDNF content in brain structures of rats after long-term ethanol exposure.