GB-115 SprayFor research use only. Not for human consumption.

For In Vitro Research Use Only – Not for Human or Veterinary Application

GB-115: a capped dipeptide modelled on CCK-4

GB-115 is N-(6-phenylhexanoyl)glycyl-L-tryptophanamide: a glycine-tryptophan dipeptide capped with a phenylhexanoyl group at one end and an amide at the other. C25H30N4O3, 434.5 g/mol, PubChem CID 11281948. PubChem also lists CAS 678996-63-9.

It came out of the "dipeptide drugs" programme at the V. V. Zakusov Research Institute of Pharmacology in Moscow, the same programme that produced Noopept. Its designers built it as a retro-analog of cholecystokinin-4 (CCK-4), the four-residue fragment of the gut-brain hormone cholecystokinin. In that series, chirality decided direction: L-Trp analogs behaved one way in rodent anxiety tests and D-Trp analogs the opposite way. GB-115 is the L-form.

Mechanism

It is described as an antagonist at central CCK receptors. NMR work identified a βII-turn, mimicking the shape of CCK-4's active site, as its active conformation. Which CCK receptor subtype it acts on is reported inconsistently: CCK1 in one paper, CCK2 in another, "central, low-affinity" in others. In rodents it blocked anxiety-like behaviour induced by CCK-4 but not by yohimbine.

Research record

• Design, synthesis and conformational analysis (2007, 2013)
• Rodent pharmacokinetics: resistant to peptidases, low oral bioavailability
• Rodent behavioural models: anxiety, benzodiazepine withdrawal, alcohol motivation, forced swim, nociception
• Inflammation and immune models, and one rhesus monkey isolation-stress study

All of it comes from Zakusov-affiliated groups, and every study we found used oral or intraperitoneal dosing. There is no published work on GB-115 in nasal solution. It isn't registered as a medicine anywhere.

Batch

Lot PCS-GB-2726O: 97.1% by quantitative ¹H NMR, NuMega Resonance Labs. 10 mg of GB-115 per bottle in sterile water, filtered through a 0.22 µm filter during production, in a 15 mL white coated glass bottle with a spray top.

Sources

• Design and L/D series, 2007: PMID 17886432
• βII-turn conformation: PMID 24397028
• CCK-4 vs yohimbine model: PMID 23113301
• Pharmacokinetics: PMID 18457023
• Rhesus monkey study (2025): PMID 39847298
• PubChem: CID 11281948

Disclaimer
This compound has not been evaluated by the FDA. It is not intended to diagnose, treat, cure, or prevent any disease. All use must follow institutional and regulatory guidelines.

Terms of Sale
By purchasing, the buyer affirms they are a qualified researcher or institution. All sales are final. The purchaser assumes full responsibility for handling, use, and regulatory compliance. GB-115 Spray reference material is supplied for qualified in vitro laboratory research only — not for human or veterinary consumption, administration, compounding, dispensing, diagnostic use, therapeutic use, or patient use.