Selank vs semax
Every row cites its source. Where a cell reflects our own reading of the evidence rather than an external source, the row says so.
| Dimension | Selank | Semax | Source |
|---|---|---|---|
| What it is | Synthetic heptapeptide Thr-Lys-Pro-Arg-Pro-Gly-Pro; tuftsin plus Pro-Gly-Pro | Synthetic heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro; an analog of the ACTH(4-10) fragment | source |
| Molecular weight | 751.9 (C33H57N11O9) | 813.9 (C37H51N9O10S) | source |
| Russian classification | Listed as a registered Russian peptide drug, classified anxiolytic | Listed in the same table as a registered Russian peptide drug, classified nootropic | source |
| US status | Not FDA approved; selank acetate (TP-7) listed as nominated but withdrawn, with an immunogenicity concern | Not FDA approved; separate FDA entry stating no or limited safety information for proposed routes | source |
| Shared mechanism | Inhibits human serum enkephalin-degrading enzymes, IC50 20 micromolar | Inhibits the same enzymes more potently, IC50 10 micromolar | source |
| Sport status | Not named on the 2026 WADA list; placed in the unclear column by an anti-doping review, with no prohibited analog listed | Not named on the 2026 WADA list either, but the same review flags it as similar to tetracosactide, a prohibited S2 substance | source |
| Found together | Identified in seized preparations analysed by a Belgian government laboratory | Identified in the same seized preparations, by the same laboratory | source |
| Evidence problem | 57 PubMed papers, 26 in Russian, zero original studies from a non-Russian institution | Shares the same Russian-literature concentration; see semaxlabs.com for that compound's own census | source |
The two Russian heptapeptides are constantly confused and often sold together. They came out of the same research programme and share a mechanism, but they are different molecules with different classifications and, in sport, different risk profiles. We run a sister reference site on semax at semaxlabs.com; every row below cites a primary source rather than either site.
Researching Selank vs semax itself? Its dedicated guide site is at semaxlabs.com.