FGL Peptide
A 15-amino-acid synthetic peptide derived from the second fibronectin-type-III module of NCAM, designed to mimic NCAM's interaction with FGFR1 and reproduce downstream neurogenic signaling. Preclinical cognition and neuroprotection data only; no human clinical trials; research-only.
A 15-residue peptide (EVYVVAENQQGKSKA) mimicking a binding motif of the second fibronectin type-III (F3) module of the neural cell adhesion molecule (NCAM). Designed by Elisabeth Bock's group (University of Copenhagen) to replicate NCAM's interaction with fibroblast growth factor receptor 1 (FGFR1). Preclinical studies report that FGL crosses the blood-brain barrier, activates FGFR1, promotes hippocampal neurogenesis, reduces amyloid-β induced neurotoxicity, and improves spatial learning in rodent models. No human clinical data. Research-chemical only.
Mechanism of action
Mimics a FGFR1-binding motif within the NCAM F3 module. Engages FGFR1 at the cell surface, triggering dimerization and autophosphorylation with downstream activation of the PLCγ, MAPK/ERK, and PI3K/Akt pathways. In preclinical studies this has been associated with increased adult hippocampal neurogenesis (as measured by BrdU incorporation in the dentate gyrus), reduced amyloid-β-induced hippocampal cell death, and improved performance in Morris water maze and fear conditioning paradigms. Mechanism is preclinically characterized but has never been validated clinically.
Primary uses
- Cognitive enhancement research (preclinical only)
- Alzheimer disease models (rodent)
- Post-stroke neurogenesis research (rodent)
Typical dosing
⚠ No human dosing established. Rodent studies commonly used 1–10 mg/kg subcutaneous or intranasal. Any human use would be entirely unregulated and unsupported by clinical evidence.
Educational information, not medical advice. The doses on this page come from approved labels, published studies and, where no study exists, amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
Regulatory status
Not FDA-approved. No registered human clinical trials. Circulates in the research-chemical grey market as a putative nootropic; any human use would be unapproved and unsupported by human safety data.
Status as of this entry's last review, October 4, 2026. Approvals, compounding rules and sport rules change; the regulatory tracker is checked more often.
What we checked
FGL is a 15-residue peptide cut from the cell-adhesion molecule NCAM, designed to activate the FGF receptor. Its literature is in cells and rodents; this section records what can be checked.
Identity, computed
| Sequence | Glu-Val-Tyr-Val-Val-Ala-Glu-Asn-Gln-Gln-Gly-Lys-Ser-Lys-Ala (EVYVVAENQQGKSKA) |
| Formula | C71H116N20O25 |
| Average mass | 1649.82 g/mol |
| Monoisotopic mass | 1648.842 Da |
| Isoelectric point | 6.52 (net charge -0.02 at pH 7) |
The dataset gives Glu-Val-Tyr-Val-Val-Ala-Glu-Asn-Gln-Gln-Gly-Lys-Ser-Lys-Ala; the formula and masses below are computed from that sequence as a free acid.
Regulatory status, read October 5, 2026
Drugs@FDA: 0 records for “FGL peptide”. EMA medicines list: 0 records for “FGL peptide”. Run for semaglutide, the same queries return 6 and 5 records (and the registry search 84 trials), so a zero here is an absence, not a broken search. Not named on the WADA 2026 and 2027 Prohibited Lists. As a substance with no current approval for human therapeutic use, it falls under section S0 (non-approved substances), which is prohibited at all times; the lists were read on September 27, 2026.
What the maker or sellers claim
Claim, from research-chemical sellers: FGL is a nootropic that improves memory and protects neurons in people. Its studies are in cells and rodents.
About NCAM and the FGF receptor
NCAM is a neural cell-adhesion molecule whose binding to the FGF receptor 1 drives nerve-cell outgrowth. FGL was designed in 2004 to mimic that contact; the founding paper is cited in References.
What we looked for and did not find
No human study, no registry record, no pharmacokinetic data in people and no dose from a controlled human study.
| Source | Query | Results, October 5, 2026 | What it was |
|---|---|---|---|
| PubMed | FGL peptide NCAM | 34 | the NCAM-derived peptide literature |
| PubMed | FGL FGFR1 NCAM mimetic | 4 | mechanism papers |
| ClinicalTrials.gov | FGL peptide | 0 | |
| Drugs@FDA (openFDA) | FGL peptide | 0 | |
| EMA medicines list | FGL peptide | 0 |
References
- [pubmed] Neiiendam JL, et al. "An NCAM-derived FGF-receptor agonist, the FGL-peptide, induces neurite outgrowth and neuronal survival in primary rat neurons." J Neurochem, 2004;91:920-935. PMID: 15525346.
- [pubmed] Knafo S, et al. "The NCAM-derived peptide FGL facilitates the intermediate stage of synaptic consolidation and the induction of LTP in the rat hippocampal CA1." J Neurosci, 2005;25:8459-8466.
- [pubmed] Corbett NJ, et al. "FGL-peptide, an NCAM-derived agonist of FGFR1, reduces tau phosphorylation in rat hippocampus." PLoS One, 2013;8:e56047.
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Guides & tools
This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.