MT2 Peptide (Melanotan II): Research Summary & Public Record
Disclaimer: All content on this site is an educational summary of public academic and industry research, compiled for informational reference only. It is not medical or laboratory advice. No treatment, health, or purchasing decisions should be made based solely on website content. This site does not sell peptides, does not link sellers, and does not endorse any vendor or any use of any compound.
Definition and core facts
mt2 peptide is melanotan II: a synthetic 7-residue cyclic lactam analog of α-melanocyte-stimulating hormone (α-MSH), sequence Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 — an N-terminal acetylated, C-terminal amidated (see amide peptides) ring with a D-phenylalanine and a norleucine substitution. The design goal of the original University of Arizona work in the 1990s was a longer-acting melanocortin ligand than the natural hormone.
Melanotan II is distinct from melanotan I (afamelanotide, Scenesse), its linear 13-residue sibling, which is an approved medicine for erythropoietic protoporphyria in the EU and elsewhere. Melanotan II itself is not approved anywhere — it is an unapproved research compound that appears on doping and customs enforcement lists, and public-health agencies have warned about unregulated products sold under related names. The research record and the regulatory record are the story.
Structure and mechanism
Pharmacologically, mt2 is a non-selective melanocortin receptor agonist — activity documented at MC1R (the tanning and pigment pathway), MC3R, MC4R (the appetite and metabolic pathway) and MC5R. That breadth explains both the research interest and the side-effect record: published trial and surveillance data associate melanotan II with nausea, flushing, blood-pressure changes, new moles and darkened pigmented lesions — the reason dermatology literature flagged it years before enforcement caught up.
Structure-activity: the cyclic constraint and the D-Phe/Nle substitutions slow proteolysis and increase potency relative to linear α-MSH — the same design logic (“modify the degradation-exposed atoms, keep the pharmacophore geometry”) that runs through the incretin engineering described in the science pillar.
How it is measured and used in research
The research-market status of mt2 is the cluster's clearest case study in why research-use-only framing matters: sold as a research chemical, consumed by end-users, unregulated in content. Published forensic analyses of “melanotan” products found dosing inconsistency and contamination — the exact failure modes the vendor pillar's documentation standards exist to expose. No vendor page on this site endorses any use of it.
Measurement: LC-MS confirmation of the 1,024-Da monoisotopic mass (7 residues plus acetyl/amide caps and ring), HPLC content, and stability like any other research peptide — see handling practice and the analysis pages.
Research context and related pages
Related research-compound case studies in this cluster: bcp157 peptide (the rodent-literature compound), tesamorelin peptide (the approved contrast case) and the incretin family in the pillar. Together they map the regulatory spectrum: approved, investigational, unapproved.
The hub is the peptide science & research pillar; the market context is the vendor research pillar. Both treat mt2 the same way: document the record, grade the evidence, make no usage recommendation.
How to use the data on this page
Step 1 — extract the parameters. Extract: sequence, ring topology, terminal caps, receptor panel (MC1R/3R/4R/5R), regulatory status by jurisdiction.
Step 2 — normalize before comparing. Normalize: melanotan I (afamelanotide) and melanotan II are different molecules — never merge their records in comparison tables.
Step 3 — grade the source. Grade: primary pharmacology and trial literature Tier 1-2; regulatory warnings Tier 1; vendor marketing not graded.
Parameter comparison
The melanotan family and their regulatory records.
| Compound | Structure | Status | Notes |
|---|---|---|---|
| alpha-MSH (natural) | Ac-SYSMEHFRWGKPV-NH2, 13-residue linear | Endogenous hormone | Rapidly degraded |
| Melanotan I (afamelanotide) | Linear 13-residue analog | Approved (EPP indication) | Marketed as Scenesse |
| Melanotan II (mt2) | 7-residue cyclic lactam | Unapproved everywhere | Doping/customs lists |
Table: The melanotan family and their regulatory records. — compiled from public regulatory and academic sources; verify against the original documents before use.
Frequently asked questions
Is MT2 a peptide?
Yes — melanotan II is a true 7-residue cyclic peptide (peptide bonds, N-acetyl and C-amide caps). It is sometimes confused with small molecules sold alongside peptides, but structurally it is a peptide in every sense covered by this site's pages.
Is MT2 approved or safe for use?
No. Melanotan II is not approved by any major regulator, appears on doping and customs enforcement lists, and published data associate it with significant adverse effects including pigmentary changes. This site covers it strictly as research documentation and makes no usage recommendation in any direction.
References
- Hruby VJ et al. Melanotan II structure-activity literature (University of Arizona lineage).
- Regulatory and public-health warnings on melanotan products (health agencies, Tier 1).
- WADA prohibited list (non-approved substances section).