Independent · non-commercial · publishes on a quarterly cycle|Current cycle 2026 Q3
Compound Evidence InstituteEvidence synthesis · established 2023Graded assessments of compounds, trials, methods and supply
Document set current to 30 July 2026
Compound monograph · Melanocortin receptor agonists

Melanotan-II — compound monograph

Non-selective melanocortin receptor agonist (cyclic heptapeptide). Unapproved, research supply. The Institute assesses 2 outcomes for this compound and grades the strongest at very low certainty.

Document identifier
CEI-MN-049
Series
Compound monograph
Version
3.3
Published
02 Sep 2023
Last reviewed
02 Dec 2024
Next review
02 Dec 2026
Identifier
10.71829/cei.mono.49
Certainty
Very low
Cycle
2023 Q3

§1Identification and status

§1.1Nomenclature

Preferred name
Melanotan-II
Compound class
Non-selective melanocortin receptor agonist (cyclic heptapeptide)
Assessment series
Melanocortin receptor agonists
Synonyms and codes
MT-II · MT2 · melanotan 2 · Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2
Route as evaluated
Subcutaneous in unregulated use

§1.2Chemistry

Chemical identifiers are reproduced where they are public. Where a structure has not been published the monograph records not disclosed rather than constructing one.[1]

CAS registry number
121062-08-6
Molecular formula
C50H69N15O9
Average mass
1024.18
Monoisotopic mass
1023.54
ATC classification
not assigned

§1.3Sequence and structural notes

Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂

The C-terminally amidated analogue of bremelanotide, differing from it by a single dalton. It was developed as a tanning agent and was never approved in any jurisdiction. Its close structural relationship to an approved medicine, combined with a 1 Da mass difference, makes the pair analytically instructive and practically hazardous to confuse.

§1.4Assessment status

The Institute assesses Melanotan-II across 2 indications and grades the strongest of them at very low certainty. Supplied as a research chemical; no marketing authorisation for the uses under which it is supplied.

Distribution of certainty ratingsShare of assessed outcomes at each certainty level.2assessed outcomes
HighModerateLowVery low
Figure 1. Distribution of certainty ratings across the 2 outcomes the Institute assesses for Melanotan-II. A rating attaches to a specific population, comparator and outcome and does not transfer between them.

Table 1. Assessed outcomes for Melanotan-II, ordered by certainty. Each row links to the per-indication evidence extract.

IndicationEffect as recordedCertaintyTrials
Hypoactive sexual desire and erectile dysfunctionNo adequately powered randomised trial identified for this compoundVery low0
Obesity and overweight in adultsNo randomised trial identifiedVery low0
Effects are reproduced as the contributing trials reported them. Where a confidence interval is held it appears on the per-indication extract rather than in this summary table.

References cited on this page

References are numbered in order of first citation in this document. Each superscript in the text links to its entry below.

  1. International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Q6B Specifications: Test Procedures and Acceptance Criteria for Biotechnological/Biological Products. ICH Harmonised Tripartite Guideline 1999;Step 4 version. identifier not held by the Institute

Identifiers are reproduced only where the Institute holds them. Where a digital object identifier or PubMed identifier is not shown, the Institute has recorded the journal and year and has not constructed an identifier.

Nothing published by the Institute is medical advice, a diagnosis, a prescription, a treatment recommendation or a purchasing recommendation. Compounds supplied for research use are not approved for human or veterinary use in any jurisdiction, and a favourable analytical assessment of a supplier is not a statement that any product is safe or effective. The Institute publishes certainty ratings and never recommendations. No telephone number, messaging handle or ordering channel appears anywhere on this site.