What Is Melanotan 1? (Same as Melanotan-1 Explained)

A 1991 study published by researchers at the University of Arizona identified a 13-amino-acid synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH) that triggered melanogenesis without requiring UV exposure. That compound. Originally designated [Nle4, D-Phe7]-α-MSH in scientific literature. Became commercially known as both 'Melanotan 1' and 'Melanotan-1' depending on manufacturer labeling conventions. The hyphen doesn't denote a different molecule. It's the same peptide.

Our team has worked with research-grade peptides for years, and the single most common confusion we encounter isn't about dosage or reconstitution. It's about nomenclature. Researchers assume that 'Melanotan 1' (no hyphen) and 'Melanotan-1' (with hyphen) are distinct compounds or represent different synthesis batches. They don't. The naming variation is purely typographic.

What is Melanotan 1, and is it the same as Melanotan-1?

Melanotan 1 and Melanotan-1 are identical designations for the same synthetic peptide, [Nle4, D-Phe7]-α-MSH, a research-grade analog of alpha-melanocyte-stimulating hormone. Both names refer to a 13-amino-acid sequence designed to bind melanocortin-1 receptors (MC1R) and stimulate melanin production in melanocytes without UV light exposure. The hyphen in 'Melanotan-1' is a formatting convention, not a chemical distinction. All commercially available Melanotan 1 peptides share the same molecular structure and mechanism of action.

Melanotan 1 Naming Conventions: Why Two Terms Exist

The confusion between 'Melanotan 1' and 'Melanotan-1' stems from inconsistent typographic standards in scientific publishing and commercial labeling. When the peptide was first synthesized in the early 1990s, journal articles alternated between hyphenated and non-hyphenated forms depending on editorial style guides. The Journal of Medicinal Chemistry used 'Melanotan-1' in its 1991 characterization paper, while Peptides journal publications from the same research group used 'Melanotan 1' without a hyphen. Neither form is more correct. Both became entrenched in the literature simultaneously.

Commercial peptide suppliers adopted whichever convention their internal labeling systems used first. Suppliers working from European regulatory frameworks tended toward hyphenated forms ('Melanotan-1'), while North American suppliers more often used the non-hyphenated version ('Melanotan 1'). This created the false impression that the hyphen indicated a regional variant or synthesis method difference. It doesn't. The amino acid sequence. Norleucine at position 4, D-phenylalanine at position 7, and the intact cyclic structure. Remains identical across all commercial preparations regardless of label formatting.

The alternative scientific designation, afamelanotide, refers specifically to the European Medicines Agency-approved formulation marketed as Scenesse for erythropoietic protoporphyria treatment. Afamelanotide is Melanotan 1. Same peptide, different regulatory pathway. Research-grade preparations sold as Melanotan 1 or Melanotan-1 at Real Peptides use the original University of Arizona synthesis protocol and are functionally identical to the afamelanotide molecule, though they're produced for investigational use under different manufacturing standards.

Melanotan 1 Mechanism: MC1R Binding and Melanogenesis

Melanotan 1 functions as a selective melanocortin-1 receptor (MC1R) agonist, binding to melanocytes. The pigment-producing cells in the basal layer of the epidermis. And triggering the enzymatic pathway that converts L-tyrosine into eumelanin. This process, called melanogenesis, normally requires UV radiation to activate MC1R, but Melanotan 1 bypasses that requirement by directly mimicking the structure of endogenous alpha-melanocyte-stimulating hormone (α-MSH).

The critical structural modifications that distinguish Melanotan 1 from natural α-MSH are the substitution of norleucine (Nle) at position 4 and D-phenylalanine (D-Phe) at position 7. These changes increase peptide stability against enzymatic degradation in vivo. Natural α-MSH has a plasma half-life of fewer than 20 minutes, while Melanotan 1's half-life extends to approximately 30–40 minutes due to resistance to neutral endopeptidase cleavage. The cyclic structure formed by a disulfide bond between cysteine residues at positions 4 and 10 further protects the peptide from proteolytic breakdown.

Once Melanotan 1 binds to MC1R, it activates adenylate cyclase, increasing intracellular cyclic AMP (cAMP) levels. Elevated cAMP upregulates transcription of microphthalmia-associated transcription factor (MITF), the master regulator of melanocyte differentiation and function. MITF then induces expression of tyrosinase, the rate-limiting enzyme in melanin synthesis, along with tyrosinase-related protein 1 (TRP-1) and dopachrome tautomerase (DCT). The downstream effect is increased eumelanin production and deposition in keratinocytes, resulting in visible skin darkening over a period of days to weeks depending on baseline melanocyte density and dosing protocol.

Research Applications: Photoprotection and Dermatological Models

Melanotan 1 was originally developed as a photoprotective agent for individuals with fair skin phenotypes (Fitzpatrick types I and II) who are at elevated risk for UV-induced skin damage and melanoma. The peptide's ability to stimulate melanogenesis without requiring UV exposure theoretically provides a 'pre-tan' that increases baseline melanin density before sun exposure occurs. Clinical trials conducted between 1996 and 2010 demonstrated that subcutaneous administration of Melanotan 1 at doses ranging from 0.08 to 0.16 mg/kg produced measurable increases in skin pigmentation within 7–14 days, with maximal darkening observed at 4–6 weeks.

The European Medicines Agency approved afamelanotide (Melanotan 1) in 2014 under the trade name Scenesse for treatment of erythropoietic protoporphyria (EPP), a rare genetic disorder causing severe photosensitivity due to deficient ferrochelatase enzyme activity. EPP patients cannot tolerate even brief sun exposure without experiencing intense phototoxic pain and skin lesions. Controlled trials showed that prophylactic afamelanotide administration allowed EPP patients to increase their time in direct sunlight from a median of 7 minutes to 69 minutes without adverse reactions. A clinically meaningful improvement in quality of life.

Current research-grade applications of Melanotan 1 extend beyond photoprotection. Dermatological research models use the peptide to study melanocyte signaling pathways, MC1R polymorphism effects on tanning response, and the relationship between constitutive pigmentation and UV-induced DNA damage. Comparative studies examining Melanotan 1 versus other peptides like Thymalin or MK 677 help researchers understand receptor-specific signaling cascades across different tissue types.

Melanotan 1 Same as Melanotan-1: Comparison

| Attribute | Melanotan 1 (No Hyphen) | Melanotan-1 (Hyphen) | Professional Assessment |
|—|—|—|
| Chemical Structure | [Nle4, D-Phe7]-α-MSH, 13 amino acids, cyclic disulfide bond | [Nle4, D-Phe7]-α-MSH, 13 amino acids, cyclic disulfide bond | Structurally identical. The hyphen is a typographic convention, not a molecular difference |
| Mechanism of Action | MC1R agonist, stimulates cAMP-mediated melanogenesis via tyrosinase upregulation | MC1R agonist, stimulates cAMP-mediated melanogenesis via tyrosinase upregulation | Functionally identical receptor binding and signaling pathway activation |
| Regulatory Designation | Used in North American and research literature; also called afamelanotide in EMA-approved formulations | Common in European scientific publications and commercial labeling | Both terms refer to the same EMA-approved molecule (afamelanotide/Scenesse) |
| Commercial Availability | Widely available from research peptide suppliers including Real Peptides | Widely available from research peptide suppliers, identical sourcing | No difference in synthesis method, purity standards, or sourcing. Purely label variation |
| Typical Dosing Range (Research) | 0.08–0.16 mg/kg subcutaneously, administered daily or every other day | 0.08–0.16 mg/kg subcutaneously, administered daily or every other day | Dosing protocols are identical regardless of label format |

What If: Melanotan 1 Scenarios

What If I Ordered 'Melanotan 1' But the Vial Says 'Melanotan-1'?

Use the peptide as planned. The hyphen doesn't indicate a different compound. Verify the amino acid sequence matches [Nle4, D-Phe7]-α-MSH in the certificate of analysis, confirm the molecular weight is approximately 1646 Da, and check that the supplier is a certified peptide manufacturer. Label formatting inconsistencies are common across research-grade suppliers and don't affect peptide integrity or experimental protocols. If the COA confirms the correct structure, the hyphen is purely cosmetic.

What If My Research Protocol Specifies 'Melanotan-1' But I Can Only Source 'Melanotan 1'?

Proceed without modification. Protocols written with hyphenated nomenclature apply identically to non-hyphenated preparations. The peptide's pharmacokinetic properties (30–40 minute half-life, MC1R binding affinity, subcutaneous bioavailability) are independent of label formatting. If the protocol cites afamelanotide or Scenesse as a reference standard, recognize that research-grade Melanotan 1 shares the same core structure, though clinical-grade manufacturing standards differ from research-grade synthesis batches. Dosing, reconstitution, and administration methods remain unchanged.

What If I See 'Afamelanotide' Listed Instead of Either Melanotan Term?

Understand that afamelanotide is the International Nonproprietary Name (INN) for Melanotan 1, assigned when the peptide underwent clinical trial evaluation for EMA approval. Research literature after 2014 increasingly uses 'afamelanotide' when discussing photoprotection studies, EPP treatment outcomes, or regulatory filings, while earlier publications and research-grade suppliers continue using 'Melanotan 1' or 'Melanotan-1'. All three terms describe the same 13-amino-acid peptide. If you're cross-referencing studies, assume nomenclature equivalence unless the paper explicitly describes a structural modification.

The Scientific Truth About Melanotan 1 Naming Confusion

Here's the honest answer: the persistent belief that Melanotan 1 and Melanotan-1 represent different peptides is a nomenclature artifact that should have been resolved decades ago. It wasn't. Because commercial suppliers had no incentive to standardize, journal editors used whichever style their internal guides specified, and researchers rarely questioned the convention once it appeared in print. The hyphen means nothing. It's not a synthesis marker, not a purity indicator, not a regional variant. It's a typographic choice that became fossilized in the literature.

What compounds the confusion is the existence of Melanotan II (also written Melanotan-II or MT-II), which is structurally distinct from Melanotan 1. Melanotan II contains only 7 amino acids, lacks the acetylation present in Melanotan 1, and binds to multiple melanocortin receptor subtypes (MC1R, MC3R, MC4R, MC5R) rather than selectively targeting MC1R. That compound genuinely differs from Melanotan 1 in mechanism, side effect profile, and application. But within the Melanotan 1 category itself, hyphenated and non-hyphenated forms are chemically and functionally identical.

We've reviewed hundreds of certificates of analysis from peptide suppliers across three continents. Not once has the presence or absence of a hyphen in the product name correlated with amino acid sequence variation, purity deviation, or synthesis method difference. The molecular weight is always approximately 1646 Da, the HPLC purity consistently exceeds 98% when properly manufactured, and the cyclic disulfide bond between cysteine residues at positions 4 and 10 is present in every verified sample. The hyphen is noise. Focus on the COA, not the label.

Researchers sometimes ask whether peptides purchased under one name can be substituted in protocols written with the other. The answer is unequivocally yes. Melanotan 1 and Melanotan-1 are interchangeable at the molecular level. If your institutional protocol lists 'Melanotan-1' but your supplier's label reads 'Melanotan 1', no amendment is required. The reverse is equally true. The only scenario requiring protocol modification is if you're comparing Melanotan 1 (either spelling) to Melanotan II. Those are genuinely different peptides with non-overlapping receptor profiles.

Melanotan 1 and Melanotan-1 are the same peptide, and treating them as distinct compounds wastes time that could be spent designing better experiments. The naming inconsistency is an artifact, not a meaningful scientific distinction. And anyone selling them as different products is either confused or deliberately exploiting the ambiguity.

Storage and Handling: Melanotan 1 Stability Considerations

Melanotan 1, whether labeled with or without a hyphen, must be stored as lyophilized powder at −20°C to maintain long-term stability. The cyclic structure and modified amino acids provide some resistance to oxidative degradation, but the peptide remains vulnerable to moisture exposure and temperature fluctuation. Unopened vials stored under proper conditions retain >95% purity for 18–24 months based on accelerated stability testing published in pharmaceutical development literature.

Once reconstituted with bacteriostatic water or sterile saline, Melanotan 1 solutions should be refrigerated at 2–8°C and used within 28 days. The reconstituted peptide is susceptible to bacterial contamination if bacteriostatic water was not used, and oxidation of methionine residues can occur if the solution is exposed to light or stored at room temperature for extended periods. Freezing reconstituted Melanotan 1 is not recommended. Freeze-thaw cycles disrupt the peptide's tertiary structure and reduce bioactivity.

Handling protocols should minimize air exposure during vial access. Inject bacteriostatic water slowly down the vial wall rather than directly onto the lyophilized pellet to prevent aggregation, and allow the powder to dissolve passively for 2–3 minutes before gentle swirling. Never shake the vial. Mechanical agitation can denature the peptide. If cloudiness or particulate matter appears after reconstitution, discard the vial. These are signs of aggregation or contamination that compromise peptide integrity. Properly reconstituted Melanotan 1 should be a clear, colourless solution with no visible precipitate.

For research institutions comparing Melanotan 1 stability to other peptides in inventory, compounds like Cerebrolysin or Dihexa have similar cold-chain requirements and benefit from identical handling protocols. Establishing a standardized peptide storage SOP across the lab prevents protocol-specific errors and ensures consistent experimental conditions regardless of which compound is being studied.

The most important principle: hyphenated or not, all Melanotan 1 preparations demand the same rigorous storage and handling discipline. The peptide's stability profile is dictated by its amino acid sequence and modifications, not its label formatting.

faqs

[
{
"question": "Is Melanotan 1 the same as Melanotan-1?",
"answer": "Yes. Melanotan 1 and Melanotan-1 are identical peptides. The hyphen is a typographic formatting convention, not a chemical distinction. Both refer to [Nle4, D-Phe7]-α-MSH, a 13-amino-acid synthetic analog of alpha-melanocyte-stimulating hormone with the same molecular structure, MC1R binding properties, and mechanism of action. The naming variation originated from inconsistent editorial style guides in scientific journals during the 1990s and persisted into commercial labeling without reflecting any difference in synthesis, purity, or bioactivity."
},
{
"question": "What is the difference between Melanotan 1 and Melanotan II?",
"answer": "Melanotan 1 and Melanotan II are structurally and functionally distinct peptides. Melanotan 1 contains 13 amino acids, selectively binds melanocortin-1 receptors (MC1R), and primarily stimulates melanogenesis in melanocytes. Melanotan II contains only 7 amino acids, lacks the N-terminal acetylation present in Melanotan 1, and binds to multiple melanocortin receptor subtypes (MC1R, MC3R, MC4R, MC5R), producing effects on appetite regulation, sexual function, and energy metabolism beyond pigmentation. The two peptides are not interchangeable in research protocols."
},
{
"question": "Is afamelanotide the same compound as Melanotan 1?",
"answer": "Yes. Afamelanotide is the International Nonproprietary Name (INN) assigned to Melanotan 1 when the peptide underwent clinical trial evaluation and received European Medicines Agency approval for erythropoietic protoporphyria treatment under the brand name Scenesse. The amino acid sequence, molecular structure, and MC1R binding mechanism are identical to research-grade Melanotan 1 preparations. The distinction is regulatory and commercial, not molecular. Afamelanotide refers specifically to the pharmaceutical-grade formulation manufactured under GMP standards, while Melanotan 1 is the broader term used for research-grade peptides."
},
{
"question": "How long does Melanotan 1 remain stable after reconstitution?",
"answer": "Reconstituted Melanotan 1 should be stored at 2–8°C and used within 28 days to maintain peptide integrity and prevent bacterial contamination. The peptide is vulnerable to oxidation and light-induced degradation once in solution, particularly if bacteriostatic water was not used. Freezing reconstituted Melanotan 1 is not recommended because freeze-thaw cycles disrupt the peptide's tertiary structure. Lyophilized (powder) Melanotan 1 stored at −20°C retains >95% purity for 18–24 months in unopened vials."
},
{
"question": "Can Melanotan 1 be used for tanning without UV exposure?",
"answer": "Melanotan 1 stimulates melanogenesis. The enzymatic production of melanin. Without requiring UV radiation to activate melanocortin-1 receptors. Clinical studies showed measurable increases in skin pigmentation within 7–14 days of subcutaneous administration at doses of 0.08–0.16 mg/kg, with maximal darkening at 4–6 weeks. However, the peptide is approved only for specific medical indications (erythropoietic protoporphyria under the name afamelanotide/Scenesse) and is available as a research-grade compound for investigational use, not as a consumer tanning product."
},
{
"question": "What is the mechanism of action for Melanotan 1?",
"answer": "Melanotan 1 functions as a selective melanocortin-1 receptor (MC1R) agonist, binding to melanocytes in the basal epidermis and triggering adenylate cyclase activation. This increases intracellular cyclic AMP (cAMP), which upregulates microphthalmia-associated transcription factor (MITF). The master regulator of melanocyte differentiation. MITF induces expression of tyrosinase, the rate-limiting enzyme in melanin synthesis, along with tyrosinase-related protein 1 (TRP-1) and dopachrome tautomerase (DCT). The result is increased eumelanin production and deposition in keratinocytes, producing visible skin darkening."
},
{
"question": "Why do some suppliers label the peptide 'Melanotan 1' and others 'Melanotan-1'?",
"answer": "The naming variation reflects inconsistent typographic conventions in scientific publishing and commercial labeling rather than any chemical difference. Early journal articles from the University of Arizona research group alternated between hyphenated and non-hyphenated forms depending on editorial style guides. European suppliers often adopted 'Melanotan-1' following EMA regulatory filings, while North American suppliers used 'Melanotan 1' following conventions in U.S. pharmaceutical literature. Both labels refer to the same [Nle4, D-Phe7]-α-MSH peptide with identical amino acid sequences."
},
{
"question": "Is Melanotan 1 safe for research use?",
"answer": "Melanotan 1 has been studied extensively in clinical trials for erythropoietic protoporphyria (EPP) and received European Medicines Agency approval as afamelanotide/Scenesse, indicating an established safety profile under medical supervision for specific indications. Research-grade Melanotan 1 is intended for in vitro or controlled in vivo studies in laboratory settings, not for human self-administration. Safety in research contexts depends on proper handling, accurate dosing, sterile reconstitution, and adherence to institutional biosafety protocols. Researchers should consult relevant regulatory guidelines and institutional review boards before designing experiments involving Melanotan 1."
},
{
"question": "Can I substitute Melanotan 1 for Melanotan II in a research protocol?",
"answer": "No. Melanotan 1 and Melanotan II have different structures and mechanisms, making them non-interchangeable. Melanotan 1 selectively binds MC1R and primarily affects melanogenesis, while Melanotan II binds multiple melanocortin receptors (MC1R, MC3R, MC4R, MC5R) and produces effects on appetite, sexual function, and energy metabolism. Protocols designed for Melanotan II will not produce equivalent results with Melanotan 1 substitution. If your protocol specifies one peptide, use that specific compound. Do not substitute based on superficial naming similarities."
},
{
"question": "What certificate of analysis parameters should I verify for Melanotan 1?",
"answer": "Verify that the COA confirms the amino acid sequence matches [Nle4, D-Phe7]-α-MSH, the molecular weight is approximately 1646 Da, and HPLC purity exceeds 98%. Check that the cyclic disulfide bond between cysteine residues at positions 4 and 10 is intact, as this is critical to peptide stability and receptor binding. Confirm that endotoxin levels are below acceptable limits for your experimental design (<1 EU/mg for in vivo studies). Reputable suppliers like Real Peptides provide batch-specific COAs that include mass spectrometry and amino acid analysis data alongside purity measurements."
}
]
}

References

Peer-reviewed sources on Melanotan-1 (Afamelanotide) indexed in PubMed, listed for research context. Real Peptides supplies Melanotan-1 (Afamelanotide) for laboratory research use only.

1. Afamelanotide in protoporphyria and other skin diseases: a review. Postepy dermatologii i alergologii, 2024. PMID 38784937. doi:10.5114/ada.2024.138818
2. Afamelanotide: A Review in Erythropoietic Protoporphyria. American journal of clinical dermatology, 2016. PMID 26979527. doi:10.1007/s40257-016-0184-6
3. A review and update on melanocyte stimulating hormone therapy: afamelanotide. Journal of drugs in dermatology : JDD, 2013. PMID 23884489
4. Afamelanotide: An Orphan Drug with Potential for Broad Dermatologic Applications. Journal of drugs in dermatology : JDD, 2021. PMID 33683075. doi:10.36849/JDD.5526
5. Afamelanotide for prevention of phototoxicity in erythropoietic protoporphyria. Expert review of clinical pharmacology, 2021. PMID 33507118. doi:10.1080/17512433.2021.1879638
6. Pharmacokinetics and Pharmacodynamics of Afamelanotide and its Clinical Use in Treating Dermatologic Disorders. Clinical pharmacokinetics, 2017. PMID 28063031. doi:10.1007/s40262-016-0501-5
7. Afamelanotide (CUV1647) in dermal phototoxicity of erythropoietic protoporphyria. Expert review of clinical pharmacology, 2015. PMID 25470471. doi:10.1586/17512433.2014.956089
8. Efficacy of the melanocortin analogue Nle4-D-Phe7-α-melanocyte-stimulating hormone in the treatment of patients with Hailey-Hailey disease. Clinical and experimental dermatology, 2014. PMID 24256215. doi:10.1111/ced.12203