PT-141 vs Melanotan II
PT-141 was derived from melanotan II. The key difference is selectivity: melanotan II activates several melanocortin receptors broadly, while PT-141 acts more selectively on central receptors, mainly MC4R.
Cyclic melanocortin-receptor agonist
Choose PT-141 if
- ✓ You need a more selective MC4R tool
- ✓ Evidence maturity matters for your design
Non-selective cyclic melanocortin agonist
Choose Melanotan II if
- ✓ You want broad melanocortin-receptor activity
- ✓ You are studying pigmentation pathways
Side-by-side specification
| Compare | PT-141 Cyclic melanocortin-receptor agonist | Melanotan II Non-selective cyclic melanocortin agonist |
|---|---|---|
| Class | Melanocortin receptor agonist | Non-selective melanocortin agonist |
| Research area | Melanocortin | Melanocortin |
| Receptor targets | MC4R (also MC1R) | MC1R, MC3R, MC4R, MC5R |
| Length | 7 amino acids (cyclic) | 7 amino acids (cyclic) |
| Molecular mass | ≈ 1.03 kDa | ≈ 1.02 kDa |
| Origin | Synthetic, derived from melanotan II | Synthetic alpha-MSH analogue |
| Evidence level | 5/5 Approved drug, phase 3 trials | 2/5 Mostly animal and in vitro |
| Regulatory status | Approved in the US only | Not approved |
| Nordapep from | Not listed | £33.88 |
| Best price per mg | Not listed | £3.39/mg |
| View PT-141 at Nordapep → | View Melanotan II at Nordapep → |
What separates them
PT-141 is FDA-approved for one indication; melanotan II has never been approved and has drawn regulator warnings about unlicensed products.
Read the full guides for PT-141 and Melanotan II, or add a third compound in the comparison tool.
FAQ
Are they the same molecule?
No. PT-141 is a related but distinct cyclic peptide with a different receptor profile.
Are PT-141 and Melanotan II approved medicines?
PT-141: Approved in the US only. Melanotan II: Not approved. Research-grade material of either is not a medicine and is supplied for in vitro research only.
Where can I buy PT-141 and Melanotan II?
Nordapep lists compounds with a Certificate of Analysis matched to the batch reference. Check each compound page for current availability.
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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.