Has Melanotan-2 been tested in a clinical trial?

No controlled efficacy trial has been published for any indication. That is unusual even by the standards of this catalogue, and it means the case reports of harm have nothing to be weighed against.

What harms have been reported with Melanotan-2?

Eruptive and atypical melanocytic naevi following injection, described in independent case reports and series from Ireland, Sweden and Australia, and reviewed as a category in the dermatological literature.

How is Melanotan-2 different from Melanotan-1?

Melanotan-1 is selective for MC1R and is approved as afamelanotide for a rare light-sensitivity disorder. Melanotan-2 binds MC1R, MC3R, MC4R and MC5R, has no approval anywhere, and no controlled efficacy trial.

Is PT-141 the same as Melanotan-2?

No, though it is derived from it. PT-141 is an active metabolite developed specifically to isolate MC4R activity and drop the pigmentation. It has its own trial programme and its own approval; Melanotan-2 has neither.

Is Melanotan-2 approved anywhere?

No. It is supplied here as a laboratory reagent for in-vitro research and not for human or veterinary use.

Research guides

Melanotan-2 (MT-II): what the research says

No controlled efficacy trial has ever been published. The indexed literature is dominated by dermatology case reports of naevi after injection.

Available in the catalogue

Supplied as research material. Sizes and pricing are on the product page. Availability is not a statement about what a compound does.

MELANOTAN-2
Cosmetic & Dermal

Most compounds in this catalogue have a literature of efficacy studies with a thin safety record attached. Melanotan-2 is the reverse. Search the indexed literature and what comes back is dermatological case reports, national case series and review articles about the consequences of unregulated use. An article that led with pigmentation mechanisms and mentioned that material at the end would be misrepresenting the published record, so this one does not.

What the molecule is

A cyclic synthetic analogue of α-melanocyte-stimulating hormone, shortened and ring-closed for stability. Published as MT-II.

Non-selective, and that is the mechanism

Unlike Melanotan-1 it binds MC1R, MC3R, MC4R and MC5R. That breadth is why it turns up in several unrelated research literatures at once — pigmentation through MC1R, appetite and sexual arousal through MC4R. PT-141, elsewhere in this catalogue, is an active metabolite of this molecule that was developed specifically to isolate the MC4R activity and leave the pigmentation behind. The existence of that spin-off is itself a comment on the parent compound: the breadth was a problem worth engineering away.

What has actually been published

Reports of eruptive and atypical melanocytic naevi following injection appear across several countries — Irish, Swedish and Australian dermatology literature among them — and a review article in 2017 examined the risks of unregulated α-MSH analogue use as a category. A Dutch clinical journal published a piece specifically on the risks of tanning with this compound. Eruptive melanocytic naevi have since been reviewed as a phenomenon in their own right.

None of this establishes a causal mechanism at the standard a controlled trial would. Case reports are the weakest study design there is. But there are a lot of them, from independent groups in different countries, describing the same phenomenon — and for a compound with no controlled efficacy literature to weigh against them, that is the entire published evidence base.

The pigmentation this molecule produces is the property people seek it for, and the reported harms concern pigmented lesions. Those are not two separate facts about the compound. They are the same pharmacology observed at two different endpoints.

What studies reported

Each entry states what a study examined and the model it used. Nothing below describes an outcome for a person.

Everything below is drawn from published research, and each entry names the model the study used. Approval status varies by compound and by country, and nothing described here is supplied as a medicine or for use in a person.

Adverse and null findings reported

Harms, tolerability observations, and trials that did not meet their endpoint. A negative result is a finding and is listed here rather than omitted.

Habbema et al. (2017)International Journal of Dermatology · 56(10):975–80
A review of the risks associated with unregulated use of α-melanocyte-stimulating hormone analogues, surveying the harms described across the published case literature.
review of case reports and clinical literature Source
Reid et al. (2013)Irish Medical Journal · 106(5):148–9
Described atypical melanocytic naevi arising following injection of material sold as melanotan.
human, case report Source
Burian et al. (2013)Läkartidningen · 110(5):208–10
Reported the first two Swedish cases of eruptive naevi following injection of drugs marketed as Melanotan II.
human, case series Source
Adler et al. (2017)Australasian Journal of Dermatology · 58(4):327–9
Set out why unregulated use of this compound is of public health interest to dermatologists, drawing on presentations seen in practice.
clinical commentary Source
Burian et al. (2019)American Journal of Clinical Dermatology · 20(5):669–82
A review of eruptive melanocytic naevi as a phenomenon, covering the reported triggers including melanocortin analogue use.
review Source
Eijmael et al. (2022)Nederlands Tijdschrift voor Geneeskunde · 166
A Dutch clinical review of the risks associated with using this compound for tanning.
clinical review Source

What the research does not establish

An absence cannot be cited, so these are stated plainly. They are the part of the picture that silence would otherwise hide.

The `reported` list above is empty, and that is the single most important fact about this compound: no controlled efficacy trial of Melanotan-2 has been published for any indication. There is nothing to weigh the case literature against.
It holds no marketing authorisation in any jurisdiction. Its selective relative Melanotan-1 is approved as afamelanotide for a rare disorder, and its metabolite PT-141 is approved as bremelanotide — but neither approval is an approval of this molecule.
Case reports cannot establish causation. What they establish is that independent clinicians in several countries described the same phenomenon in patients who had used the compound, and that no controlled study exists to test the association properly.
Because it is non-selective, any observed effect has more than one plausible receptor explanation, which makes it a poor tool for isolating any single melanocortin pathway.
Material sold under this name in the unregulated market has repeatedly been found to differ from its label, so a proportion of the published case literature concerns preparations of uncertain content.
No long-term follow-up study of any kind has been published.

Common questions

Has Melanotan-2 been tested in a clinical trial?: No controlled efficacy trial has been published for any indication. That is unusual even by the standards of this catalogue, and it means the case reports of harm have nothing to be weighed against.
What harms have been reported with Melanotan-2?: Eruptive and atypical melanocytic naevi following injection, described in independent case reports and series from Ireland, Sweden and Australia, and reviewed as a category in the dermatological literature.
How is Melanotan-2 different from Melanotan-1?: Melanotan-1 is selective for MC1R and is approved as afamelanotide for a rare light-sensitivity disorder. Melanotan-2 binds MC1R, MC3R, MC4R and MC5R, has no approval anywhere, and no controlled efficacy trial.
Is PT-141 the same as Melanotan-2?: No, though it is derived from it. PT-141 is an active metabolite developed specifically to isolate MC4R activity and drop the pigmentation. It has its own trial programme and its own approval; Melanotan-2 has neither.
Is Melanotan-2 approved anywhere?: No. It is supplied here as a laboratory reagent for in-vitro research and not for human or veterinary use.

Compounds covered

The reference page for each compound this article discusses.

Melanotan-2

Melanotan-1 (afamelanotide): what the research says
Approved in the EU and US as Scenesse for a rare light-sensitivity disorder. What the trial measured, and why the approval is narrower than it sounds.
PT-141 (bremelanotide): what the research says
Approved in the US as Vyleesi, with two phase 3 trials and a published safety programme. The mechanism is neural at MC4R, not vascular like PDE5 inhibitors.
How to store research peptides
Lyophilised peptides at -20°C, reconstituted at 2–8°C, ambient in transit. Why the dry cake tolerates shipping, and what actually degrades a vial.

About this article

Everything reported here comes from published research, and each finding names the model the study used — cell culture, rat, or human. Findings in one model do not transfer to another, most of the work described is preclinical, and none of it is a claim that a compound is safe or effective for any purpose. Nothing on this page describes doses, routes of administration, or use in a person.

Approval status varies by compound and by country. A few of the substances described are the active ingredient of medicines authorised in the EU; most have no marketing authorisation anywhere and have never been assessed by a regulator. Neither is supplied as a medicine here. All material supplied by ASSAY is sold for in-vitro laboratory research only, and is not a drug, food, cosmetic or medical device, and not for human or veterinary use.

All guides