Semaglutide vs Retatrutide
This pairing spans the whole incretin story: one receptor versus three. Semaglutide is the established single-receptor medicine; retatrutide is the investigational triple agonist.
Long-acting GLP-1 receptor agonist
Choose Semaglutide if
- ✓ You need the established GLP-1-only reference
- ✓ Evidence maturity matters most for your design
Investigational GIP, GLP-1 and glucagon triple agonist
Choose Retatrutide if
- ✓ You are studying multi-receptor agonism
- ✓ You want the newest compound in the class
Side-by-side specification
| Compare | Semaglutide Long-acting GLP-1 receptor agonist | Retatrutide Investigational GIP, GLP-1 and glucagon triple agonist |
|---|---|---|
| Class | GLP-1 receptor agonist | Triple GIP / GLP-1 / glucagon agonist |
| Research area | Metabolic | Metabolic |
| Receptor targets | GLP-1R | GIPR, GLP-1R, GCGR |
| Length | 31 amino acids (acylated GLP-1 analogue) | ≈ 40 amino acids (fatty-acid modified) |
| Molecular mass | ≈ 4.11 kDa | ≈ 4.7 kDa |
| Origin | Synthetic analogue of human GLP-1 | Synthetic |
| Evidence level | 5/5 Approved drug, phase 3 trials | 4/5 Late-stage human trials |
| Regulatory status | Approved prescription medicine | Investigational |
| Nordapep from | Not listed | £63.40 |
| Best price per mg | Not listed | £5.09/mg |
| View Semaglutide at Nordapep → | View Retatrutide at Nordapep → |
What separates them
Many labs study all three incretin peptides together, which is why Nordapep's GLP-1 Research Trio exists.
Read the full guides for Semaglutide and Retatrutide, or add a third compound in the comparison tool.
FAQ
Where does tirzepatide fit?
In the middle: it adds GIP-receptor activity to GLP-1. See the tirzepatide vs retatrutide page.
Are Semaglutide and Retatrutide approved medicines?
Semaglutide: Approved prescription medicine. Retatrutide: Investigational. Research-grade material of either is not a medicine and is supplied for in vitro research only.
Where can I buy Semaglutide and Retatrutide?
Nordapep lists compounds with a Certificate of Analysis matched to the batch reference. Check each compound page for current availability.
More comparisons
Where to buy
Why we send researchers to Nordapep
Comparing compounds is only half the job. The other half is knowing the vial contains what the label says. Nordapep publishes batch documentation for every compound it sells.
Browse the Nordapep catalogue →Each batch reference on the label matches its CoA, so you can check what is in the vial.
Enter the batch reference from your vial into Nordapep's batch-verification tool.
Purity is reported by RP-HPLC, the standard method for peptides of this size.
Bundled stacks for common comparisons, plus tiered pricing for volume orders.