Retatrutide vs Semaglutide
Semaglutide is the reference GLP-1 receptor agonist that anchors most current metabolic peptide research. Retatrutide extends that mechanism to three receptors — GLP-1, GIP and glucagon — in a single molecule.
This page compares the two so researchers can quickly see receptor profile, vial strengths, and how each one fits into an in vitro protocol.
Side-by-side
| Retatrutide | Semaglutide | |
|---|---|---|
| Receptor profile | Triple: GLP-1 / GIP / Glucagon | Single: GLP-1 |
| Class | Triple agonist | Mono agonist (GLP-1 analogue) |
| Vial strengths | 20mg · 30mg · 40mg | 30mg |
| Dosing cadence | Weekly (long-acting) | Weekly (long-acting) |
| Research maturity | Newer — frontier research | Established reference peptide |
| Purity (HPLC) | 99%+ | 99%+ |
How they differ mechanistically
Semaglutide activates the GLP-1 receptor only. It's the benchmark for characterising cAMP response, β-arrestin recruitment and receptor internalisation in GLP-1 studies.
Retatrutide pulls three levers — GLP-1, GIP and glucagon — which is why researchers use it as a comparator against mono and dual agonists to characterise receptor bias and combined signalling.
Reconstitution
Both peptides are supplied as lyophilised powder and reconstituted with bacteriostatic water. Use our free peptide calculator to work out the correct volume for your vial. Store at 2–8°C after reconstitution.
Browse related products
View full shopFrequently asked questions
What's the difference between Retatrutide and Semaglutide?
Semaglutide is a single GLP-1 receptor agonist. Retatrutide is a triple agonist — GLP-1, GIP and glucagon receptors in one molecule. The added receptors are the defining difference in research.
Which is more established in research?
Semaglutide is a long-established reference GLP-1 peptide with extensive published literature. Retatrutide is newer and sits at the frontier of triple-agonist metabolic research.
What vial strengths do you stock?
Retatrutide is available in 20mg, 30mg and 40mg vials. Semaglutide is stocked in 30mg vials. All are HPLC verified at 99%+ purity with batch COAs.
Are they dosed the same way?
Both are long-acting research peptides used in weekly protocols. Working concentrations differ — use our peptide calculator for exact volumes.
Disclaimer: All products sold by Peptides UK 4U are for laboratory and research purposes only. They are not intended for human or animal consumption, diagnosis, treatment or prevention of any disease.