What Is Melanotan II (MT-2)? A Research Overview

Melanotan II (Melanotan 2, MT-2) is a synthetic cyclic peptide and nonselective melanocortin receptor agonist — a structural analog of alpha-melanocyte-stimulating hormone (α-MSH) — studied in preclinical and in-vitro models of the melanocortin signaling system. It is sold strictly as a research-use-only (RUO) chemical. Melanotan II is not FDA-approved, is not a drug or dietary supplement, and is not intended for human or veterinary use. The statements below have not been evaluated by the Food and Drug Administration.

Quick facts

• Class: synthetic cyclic melanocortin receptor agonist (analog of α-MSH)
• Research focus: melanocortin-system research
• Form: lyophilized powder, ≥99% HPLC purity, third-party tested
• Status: research-use-only — not for human use; not FDA-approved

What is Melanotan II?

Melanotan II is a cyclic heptapeptide engineered as a stable analog of the endogenous signaling molecule α-MSH. The lactam bridge that cyclizes the molecule confers greater metabolic stability and receptor affinity than the linear native peptide, which is why investigators have used it as a pharmacological tool compound to probe melanocortin receptor biology in laboratory settings. In the published literature it is most often referred to as MT-II or MTII.

What does the research show?

Published work on Melanotan II is preclinical — conducted in cell systems and animal models — and is intended to characterize melanocortin receptor signaling rather than to establish any human application. In a rat sciatic-nerve model, one study reported that MT-II was associated with measurable changes in indices of sensory-function recovery and described neuroprotective observations in a chemically induced neuropathy model [1]. Separate rodent work examined how MT-II interacts with melanocortin receptor subtypes, using MC3-receptor knockout mice to dissect the relative contribution of individual receptors [2]. A 2025 dermatology review summarizing the broader melanocortin literature characterizes Melanotan II as a nonselective melanocortin receptor agonist and notes that it has no approved therapeutic indication [3]. These reports describe observations in controlled experimental systems and do not support conclusions about effects in humans.

Mechanisms studied in the lab

• Nonselective melanocortin receptor agonism: in binding and functional assays, MT-II activates the melanocortin receptor family (MC1R through MC5R) rather than a single subtype [3].
• Tool-compound role: its stability and broad agonism make it a reference agonist for characterizing melanocortin receptor pharmacology in vitro.
• Receptor-subtype dissection: studies pair MT-II with genetic models (e.g., receptor knockouts) to attribute responses to specific receptor subtypes [2].

Research status and safety

Melanotan II is an unapproved synthetic compound with no licensed indication in any jurisdiction. It is offered here solely as a research-use-only material for in-vitro and laboratory investigation by qualified researchers. It is not a medicine, supplement, or cosmetic, and it is not intended to diagnose, treat, cure, or prevent any disease, nor for administration to humans or animals.

Handling

Melanotan II ships as a lyophilized (freeze-dried) powder, stored cold and protected from light per the certificate of analysis. For general laboratory reconstitution practice, see our guide on how to reconstitute a research peptide. Product specifications are listed on the product page: Melanotan II (MT-2) — research-grade, ≥99% pure. Browse related research peptides in the catalog.

FAQ

How is Melanotan II different from Melanotan I? Melanotan I (afamelanotide) is a linear α-MSH analog with relatively greater selectivity, whereas Melanotan II is a smaller cyclic peptide that acts as a nonselective agonist across the melanocortin receptor family. Both are studied as research tools for the melanocortin system.

Is Melanotan II approved by the FDA? No. It has no approved indication and is offered only as a research-use-only chemical, not for human use.

What is it used for in the lab? Researchers use it as a stable reference agonist to study melanocortin receptor signaling in cell-based and animal models.

References

1. Ter Laak MP, et al. Melanotan-II promotes peripheral nerve regeneration in the rat. Eur J Pharmacol. 2003.
2. Olney JJ, et al. MTII and the MC3 receptor in mice. Neuropeptides. 2014.
3. Böhm M, et al. Benefits and risks of chronic melanocortin-1 receptor activation (review). J Eur Acad Dermatol Venereol. 2025.

For research use only. Not for human or veterinary use. Not FDA-approved. Statements have not been evaluated by the FDA.