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Therapept
Skin & Cosmetic ResearchCyclic heptapeptide

Melanotan II

Melanotan II is studied as a cyclic heptapeptide; non-selective melanocortin receptor agonist (alpha-msh analogue) in biochemical and physiological models.

UnapprovedPreclinical Models Only (Animal / Lab)Also known as: MT-II, MTIISkip to Human Evidence ↓
Other Research Areas

Melanotan II Biological Classification

Research Record

Investigated within physiological and chemical models.

1

What is Melanotan II?

Melanotan II is classified as a cyclic heptapeptide; non-selective melanocortin receptor agonist (alpha-msh analogue). A cyclic melanocortin receptor agonist with no approved drug product. It is structurally very close to bremelanotide, differing at the C-terminus.

2

Why are people interested in it?

Researchers and clinicians study Melanotan II primarily to understand its biological interactions, receptor binding affinity, and potential role within its biochemical class.

Primary Research Categories

  • Melanocortin analogues
3

How does it work in the body?

Melanotan II interacts with specific cellular receptors and metabolic pathways corresponding to its structural classification as a cyclic heptapeptide; non-selective melanocortin receptor agonist (alpha-msh analogue).

In Everyday Language: In laboratory settings, Melanotan II interacts with specific cellular targets to modulate biological signaling pathways associated with cyclic heptapeptide; non-selective melanocortin receptor agonist (alpha-msh analogue) biology.
Cellular & Receptor Signaling: Melanotan II interacts with specific cellular receptors and metabolic pathways corresponding to its structural classification as a cyclic heptapeptide; non-selective melanocortin receptor agonist (alpha-msh analogue).

Biological Pathway Overview

Melanotan II Receptor & Target Interactions

This compound is evaluated in scientific research for its interactions with target cellular receptors and signaling cascades. Consult the evidence section below for specific peer-reviewed papers.

Target Pathway

Engages specific cellular signaling cascades characteristic of its structural family.

Endocrine/Paracrine Activity

Investigated for its regulatory effects on local tissue synthesis and cellular signaling.

4

What has actually been demonstrated in humans?

Preclinical Models Only (Animal / Lab)

Evidence for Melanotan II is currently derived primarily from laboratory or preclinical models. Consult the published evidence file for specific indexed studies.

Pharmaceutical Reality vs. Unregulated Research Chemicals

Melanotan II is not an FDA-approved medication. Always verify chemical identity and testing documentation before interpreting research literature.

5

What is still uncertain or unknown?

Controlled human clinical trials evaluating Melanotan II for therapeutic efficacy, safety, and pharmacokinetics are limited or absent in peer-reviewed Western registries.

Regulatory Position: Melanotan II is an investigational or unapproved compound. It is not approved by the FDA as a commercial pharmaceutical.

Companion Resources & Guides

Evidence Landscape→

Primary research publications and study designs indexed for Melanotan II.

Dosing Reference

Open Melanotan II Dosing Reference

A pilot Phase I study exists; no approved product. The study's own conclusion was about dose selection for future Phase I work, not therapy.

Therapept separates official product labels, published clinical study interventions, animal research, clinical references, and community-reported ranges — never blended into one number.

Research at a Glance

Open the full evidence file (3 records)

3 records in this file

  • CLINICAL TRIAL1
  • REVIEW1
  • REGULATORY1

Publication span: 1996–2026

What Has Actually Been Studied

  • FDA table of bulk drug substances nominated for compounding and subsequently withdrawn (FDA compounding communications, 2026) — Regulatory listing.
  • Melanocortin peptide therapeutics: historical milestones, clinical studies and commercialization (Peptides, 2006) — Narrative review.
  • Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study (Life Sciences, 1996) — Pilot Phase I study.

What is Still Unknown

What we know

  • A 1996 pilot Phase I study explored pigmentation and tolerability in volunteers. No FDA-approved product followed.
  • It is the C-terminal amide; bremelanotide is the free-acid analogue and is approved.
  • FDA's withdrawn-nomination entry cites case reports of serious adverse events.

Editorial reading of the records below, labelled as Therapept analysis. How records are built

What remains uncertain

  • A contemporary controlled safety database. Case reports are a concern list, not an incidence rate.

Preparation and Handling

Lyophilized peptides ship as freeze-dried powders; whatever happens next involves diluents, concentrations and storage conditions that are compound- and product-specific.

Preparation Resource HubWhat “lyophilized” meansConcentration calculator

United States Regulatory Status

No FDA-approved product

  • No approved drug product exists in Drugs@FDA.
  • Listed on FDA's table of bulk substances nominated for compounding and withdrawn by the nominator.
  • FDA's published entry references case reports of serious adverse events, including melanoma, posterior reversible encephalopathy syndrome, sympathomimetic toxidrome and priapism.
  • Not named on the WADA 2026 Prohibited List.
Technical Chemical SpecificationsClick to view CAS, sequence, and molecular formulas
Molecular weight
1024.2 g/mol
Sequence length
43 chars
CAS number
121062-08-6
PubChem CID
92432
Compound class
Cyclic heptapeptide; non-selective melanocortin receptor agonist (alpha-MSH analogue)
Sequence
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2
Molecular formula
C50H69N15O9
Molecular weight
1024.2 g/mol
CAS number
121062-08-6
PubChem CID
92432