Melanotan I vs Hexapeptide-9
Comprehensive side-by-side comparison of mechanisms, dosing, side effects, and research
Also: Afamelanotide, Scenesse
Melanotan I is the research name for afamelanotide (code CUV1647), a 13-amino-acid synthetic analog of alpha-melanocyte-stimulating hormone (alpha-MSH), also written as [Nle4, D-Phe7]-alpha-MSH or NDP-MSH. Sold as Scenesse, it was approved by the EMA in 2014 and the FDA in 2019 to increase pain-free light exposure in adults with erythropoietic protoporphyria (EPP), one of a few approved melanocortin drugs alongside bremelanotide (Vyleesi) and setmelanotide (Imcivree). The approval covers only the 16 mg bioresorbable implant placed under the skin by a clinician. The injectable 'Melanotan I' sold online is not approved for anything.
Also: Collaxyl, Collaxyl IS
Hexapeptide-9 is a collagen-inspired signaling peptide sold as Collaxyl (originally from Vincience, now Ashland) for anti-wrinkle and firming skincare. The idea is that a small repeat of a collagen sequence nudges skin cells to rebuild the junction between the outer and inner skin. It is a cosmetic ingredient, and the evidence for the original peptide is mostly old, small and company-run, although a 2025 trial on a modified cyclic version is more interesting.
Key Comparison Insights
- Melanotan I is FDA approved, while Hexapeptide-9 remains in research stages.
- Both peptides belong to the Skin & Hair category, suggesting similar primary applications.
- Melanotan I has stronger research evidence (FDA Approved) compared to Hexapeptide-9 (Limited Research).
Detailed Comparison
| Attribute | Melanotan I | Hexapeptide-9 |
|---|---|---|
| Category | Skin & Hair | Skin & Hair |
| FDA Status | FDA Approved | Not FDA Approved |
| Clinical Status | Pre I II III IV FDA | Pre I II III IV FDA |
| Mechanism of Action | Afamelanotide binds and activates the melanocortin-1 receptor (MC1R) on pigment-producing melanocytes, driving production of eumelanin, the dark, photoprotective form of melanin. Two amino acid swaps from natural alpha-MSH - norleucine at position 4 and D-phenylalanine at position 7 - make it bind MC1R more tightly and resist breakdown, so it lasts far longer and acts more potently than the native hormone. The extra eumelanin absorbs and scatters light and also brings antioxidant and DNA-repair-supporting effects, which is why it raises the light dose EPP patients can tolerate before pain hits. Unlike Melanotan II, it is selective enough toward MC1R that it is not primarily a sexual-function or appetite agent. | Hexapeptide-9 is Gly-Pro-Gln-Gly-Pro-Gln, a repeat taken from collagen sequences. Ashland says the sequence is found in collagen IV and XVII and works as a matrikine, a matrix fragment that signals cells to make more matrix proteins. The claimed targets are the dermal-epidermal junction (collagen IV, laminin-5, integrins) and collagen production. The original patent describes it as designed to improve cell adhesion and possibly support matrix production. One weakness is stability: the linear peptide is easily broken down by collagen-digesting enzymes, which is why a Chinese group built a ring-shaped (cyclized) version to make it last longer in skin. |
| Common Dosing | 500-1000 mcg daily (loading), then 500-1000 mcg 1-2x weekly (maintenance) Daily during loading (1-2 weeks), then 1-2x weekly maintenance | Low single-digit percent of the ingredient in a finished product Once or twice daily |
| Administration | Subcutaneous implant (not injection) | Topical (serums, creams) |
| Typical Duration | Long-term / as needed before sun season | 4-8 weeks in studies; ongoing use to maintain any effect |
| Best Time to Take | Before the sunny season (approved implant); evening for unapproved injectables | Morning and/or evening, on clean skin |
Possible Side Effects May vary by individual |
|
|
| Research Summary | This is one of the few peptides on this list with gold-standard human evidence. The pivotal data came from two multicenter, randomized, double-blind, placebo-controlled trials published in the New England Journal of Medicine in 2015 (Langendonk et al., 373(1):48-59), enrolling 168 EPP patients across the EU (74) and US (94) who received the 16 mg implant or placebo every 60 days. Afamelanotide significantly increased pain-free time in sunlight (median 69.4 vs 40.8 hours in the US trial; 6.0 vs 0.8 hours in the EU trial, where phototoxic reactions also dropped from 146 to 77), and improved disease-specific quality of life, with mostly mild adverse events. Long-term observational follow-up of EPP patients has supported continued benefit and an acceptable safety profile. Clinuvel is also running a phase 3 vitiligo trial (CUV105), with topline results guided for December 2026. The big caveats: this approval is narrowly for EPP, not for cosmetic tanning, and the unregulated injectable 'Melanotan' products people buy online are not the same controlled, clinician-administered implant and carry real risks. Bottom line: a genuinely proven, approved drug for a rare condition, frequently misused outside that lane. | The oldest human data is a 2004 study from Vincience, the lab behind Collaxyl: a double-blind, placebo-controlled test of a gel containing 3% of a 'collagen-like hexapeptide' plus a 1% booster ingredient, applied around the eyes of 20 women for four weeks. It reported fewer and shallower wrinkles on skin replicas, but the booster and the small size mean it cannot prove the peptide alone did the work. Supplier material cites other 28-day studies in about 20 volunteers that we could not trace to journals. The newest and best-designed study is a 2025 randomized, double-blind trial in the Journal of Cosmetic Dermatology (96 adults aged 30-55 in China) comparing a cyclized hexapeptide-9 serum at 0.002% with 0.002% retinol and a vehicle for 56 days. The cyclized peptide beat both on wrinkle, elasticity and hydration measures, with no treatment-related side effects. Two caveats: it tested a modified molecule, not the Collaxyl peptide in most products, and several authors are affiliated with cosmetic companies. Bottom line: the concept has some support, the cyclic version looks promising, but regular hexapeptide-9 in a store-bought cream rests on thin evidence. |
Frequently Asked Questions: Melanotan I vs Hexapeptide-9
What is the difference between Melanotan I and Hexapeptide-9?
Melanotan I is a skin & hair peptide that melanotan i is the research name for afamelanotide (code cuv1647), a 13-amino-acid synthetic analog of alpha-melanocyte-stimulating hormone (alpha-msh), also written as [nle4, d-phe7]-alpha-msh or ndp-msh. sold as scenesse, it was approved by the ema in 2014 and the fda in 2019 to increase pain-free light exposure in adults with erythropoietic protoporphyria (epp), one of a few approved melanocortin drugs alongside bremelanotide (vyleesi) and setmelanotide (imcivree). the approval covers only the 16 mg bioresorbable implant placed under the skin by a clinician. the injectable 'melanotan i' sold online is not approved for anything. Hexapeptide-9 is a skin & hair peptide that hexapeptide-9 is a collagen-inspired signaling peptide sold as collaxyl (originally from vincience, now ashland) for anti-wrinkle and firming skincare. the idea is that a small repeat of a collagen sequence nudges skin cells to rebuild the junction between the outer and inner skin. it is a cosmetic ingredient, and the evidence for the original peptide is mostly old, small and company-run, although a 2025 trial on a modified cyclic version is more interesting. The main differences lie in their mechanisms of action and clinical applications.
Which is better, Melanotan I or Hexapeptide-9?
Neither is universally "better" - the choice depends on your specific goals. Melanotan I is typically used for skin & hair purposes, while Hexapeptide-9 is used for skin & hair. Always consult with a healthcare provider to determine which may be appropriate for your situation.
Can Melanotan I and Hexapeptide-9 be used together?
Some peptide protocols combine multiple compounds for synergistic effects. However, using Melanotan I and Hexapeptide-9 together should only be considered under medical supervision, as both compounds have their own side effect profiles and potential interactions. Research on their combined use may be limited.