Melasma and peptides: what lightens, what darkens, what is proven

No peptide has a melasma evidence base that matches tranexamic acid. Topical tyrosinase-inhibiting oligopeptides such as decapeptide-12 show favorable, well-tolerated results in small trials, often in Hispanic women, almost always combined with other actives. α-MSH analogs, including the FDA-approved afamelanotide and unapproved melanotan, do the opposite: they darken the skin.

Key points

• Melasma affects up to 10% of the Latin American population and is more common in darker phototypes [1][2].
• Afamelanotide, an α-MSH analog approved by the FDA in 2019 for erythropoietic protoporphyria, increases eumelanin. It darkens the skin and does not lighten it [5][6].
• With a regimen including 0.01% decapeptide-12, 33 Hispanic women with melasma showed a mean MASI reduction of 60% at 16 weeks, in an open-label study [8].
• Tranexamic acid, a lysine analog and not a peptide, is the benchmark. In a placebo-controlled trial in mostly Hispanic women, mMASI fell 49% versus 18% [11][12].
• Trials of anti-pigment peptides are small, short and almost always combine the peptide with other actives [7][8][9].

US status (October 2026): See the peptide status tracker.

Melasma is common in darker phototypes

Melasma is a chronic, relapsing hyperpigmentation of sun-exposed areas, most frequent in adult women with darker phototypes. Its main drivers are sun exposure, sex hormones (pregnancy, for example) and genetic predisposition [2]. A consensus of nine Latin American experts describes it as highly prevalent in the region, where many countries lie in the intertropical zone and the population reflects centuries of mixing among Native Americans, Europeans and Sub-Saharan Africans [2]. The Latin American Pigmentary Disorders Academy estimated a prevalence of up to 10% of the Latin American population [1].

For a US aesthetic practice with Hispanic patients, that data set is directly relevant. Several of the trials below were run in Hispanic women.

• Up to 10%: melasma prevalence in the Latin American population [1]
• 60%: mean MASI reduction at 16 weeks with a decapeptide-12 regimen (open-label study) [8]
• 49% vs 18%: mMASI reduction, oral tranexamic acid versus placebo [12]

The dermis drives the patch as much as the melanocyte

The classic view of melasma centers on the overactive melanocyte and on tyrosinase, the enzyme responsible for melanin overproduction [7]. Recent reviews widen the focus to the dermis: basement-membrane changes, solar elastosis, mast cells, vascular changes, senescent fibroblasts and the effect of visible light and hormonal fluctuations [3]. A 2026 review proposes viewing melasma as persistent melanocyte activation sustained by a photoaged dermis, in which senescent fibroblasts, UV-activated sebocytes and vascular components send continuous melanogenic signals. According to the authors, this would explain its midlife onset, its relapsing course and its attenuation later in life [4].

In that cascade the melanocortin 1 receptor (MC1R) is central. Its activation increases eumelanin production [5]. That fact explains why an entire family of peptides does the opposite of what a melasma patient wants.

Melanocortin peptides darken the skin

Afamelanotide is an MC1R agonist approved by the FDA in 2019, as a 16 mg subcutaneous implant, to increase pain-free light exposure in adults with a history of phototoxic reactions from erythropoietic protoporphyria [5]. In the two randomized placebo-controlled trials behind it (74 patients in Europe and 94 in the United States), pain-free direct sun exposure was longer with afamelanotide: median 69.4 versus 40.8 hours in the US study (P = 0.04) and 6.0 versus 0.8 hours in the European one (P = 0.005), with fewer phototoxic reactions (77 versus 146) [6].

Its label explains the mechanism. Afamelanotide increases eumelanin production in the skin independently of sun exposure. It warns that it “May induce darkening of pre-existing nevi and ephelides” and recommends a full-body skin examination twice a year [5]. It is an approved, effective peptide whose effect is pigmenting. The same holds, without approval or quality control, for melanotan, whose history and risks are reviewed in Melanotan II and PT-141. In a melasma patient, an α-MSH analog goes in the wrong direction. Ask about tanning peptides when a patient’s pigment worsens.

Tyrosinase-inhibiting peptides show small, favorable signals

At the other end are topical oligopeptides designed to slow melanogenesis. The best studied is a proprietary oligopeptide, sold as Lumixyl and described as decapeptide-12 in later studies, which competitively inhibited mushroom and human tyrosinase without the toxicity associated with hydroquinone [7][8]. In a randomized, double-blind, placebo-controlled split-face pilot, five women of phototype IV with moderate recalcitrant melasma applied it at 0.01% for 16 weeks. All five showed statistically significant improvement, with no visible irritation or allergy [7].

The most relevant data point for Hispanic patients is a prospective, open-label, multicenter study in 33 Hispanic women with mild to moderate melasma. With a regimen of 0.01% decapeptide-12, an antioxidant cleanser, 20% buffered glycolic acid and SPF 30 sunscreen, mean MASI fell 36%, 46%, 54% and 60% at weeks 4, 8, 12 and 16, with no adverse events reported [8].

With oligopeptide-68, a TGF-β1 biomimetic that inhibits tyrosinase, a 12-week randomized double-blind trial in 40 women (38 completed) combined the peptide with diacetyl boldine and sunscreen. Melasma improved from baseline at weeks 6 and 12 (P < 0.05) and 76.3% of participants rated their improvement as moderate [9]. Epidermal growth factor, a polypeptide, was tested in a placebo-controlled split-face trial in 15 women. After 8 weeks, GAIS scores showed improvement on 73.4% of treated sides versus 13% of placebo sides [10].

Tranexamic acid is the benchmark

Any new melasma active is now compared with tranexamic acid, which is a synthetic lysine analog mainly used as an antifibrinolytic, and not a peptide [11]. In a randomized, double-blind, placebo-controlled trial in patients with moderate to severe melasma, mostly Hispanic women, 44 patients received 250 mg twice daily or placebo for 3 months (39 completed). mMASI fell 49% with tranexamic acid versus 18% with placebo, and three months after stopping, the reduction from baseline was 26% versus 19% [12].

A meta-analysis of 22 randomized studies with 1,280 patients confirmed a significant reduction in severity by the oral, topical or injected route, with the largest MASI reduction orally. Reported adverse effects were gastrointestinal discomfort, skin irritation and menstrual irregularities, and heterogeneity between studies was high [13]. No anti-pigment peptide currently has a comparable evidence base.

Microneedling helps delivery, with limited peptide data

Microneedling is used to enhance transcutaneous penetration of actives. In a meta-analysis, microneedling plus tranexamic acid was significantly more effective than microneedling alone, although overall it did not outperform other treatments [14]. With a tripeptide, glutathione, a split-face study in 29 women with epidermal melasma compared six microneedling sessions with or without glutathione solution: improvement was 55.17% versus 46.92%, a significant difference [15]. The oral and intravenous glutathione evidence is reviewed separately in Glutathione for skin lightening. A PubMed search found no trials of decapeptide-12 or oligopeptide-68 delivered with microneedling.

The evidence has clear limits

• Trials of anti-pigment peptides are small: 5, 15, 33 and 40 participants [7][8][9][10].
• The peptide is almost always part of a combination (glycolic acid, diacetyl boldine, sunscreen), so its own contribution cannot be isolated [8][9].
• The study in 33 Hispanic women was open-label with no control group [8].
• In the oligopeptide-68 trial, the comparison with 2% and 4% hydroquinone was made on normal arm skin, not on melasma [9].
• Melasma relapses. The Latin American consensus recommends continuing topical depigmenting agents and strict photoprotection after remission [2]. No peptide study followed patients beyond 16 weeks of treatment [7][8][9][10].

What this means for your aesthetic menu

First-line care is still photoprotection and the classic depigmenting agents, with triple combination as a first-line option in moderate to severe melasma [1][2]. Tyrosinase-inhibiting oligopeptides have favorable, well-tolerated clinical signals, obtained in part in Hispanic women [8], and are a biologically sound adjunct that still needs larger trials. α-MSH analogs darken the skin by design [5]. If you add injectable peptides to a skin program, check each one on the peptide status tracker first, and keep any vial labeled for research use only out of the treatment room.

References

1. Cestari T, et al. Melasma in Latin America: options for therapy and treatment algorithm. J Eur Acad Dermatol Venereol. 2009;23(7):760-72. PMID 19646135. Link
2. Ocampo-Candiani J, et al. Latin American consensus on the treatment of melasma. Int J Dermatol. 2025;64(3):499-512. PMID 39415312. Link
3. Ali L, Al Niaimi F. Pathogenesis of Melasma Explained. Int J Dermatol. 2025;64(7):1201-1212. PMID 40022484. Link
4. Kang HY, Picardo M. Melasma: When Dermal Photoageing Precedes Melanocyte Ageing. Exp Dermatol. 2026;35(9):e70364. PMID 42746716. Link
5. U.S. Food and Drug Administration. SCENESSE (afamelanotide) implant, for subcutaneous use. Prescribing information. Initial U.S. approval: 2019. Link
6. Langendonk JG, et al. Afamelanotide for Erythropoietic Protoporphyria. N Engl J Med. 2015;373(1):48-59. PMID 26132941. Link
7. Hantash BM, Jimenez F. A split-face, double-blind, randomized and placebo-controlled pilot evaluation of a novel oligopeptide for the treatment of recalcitrant melasma. J Drugs Dermatol. 2009;8(8):732-5. PMID 19663110. Link
8. Ramírez SP, et al. Open-label evaluation of a novel skin brightening system containing 0.01% decapeptide-12 in combination with 20% buffered glycolic acid for the treatment of mild to moderate facial melasma. J Drugs Dermatol. 2013;12(6):e106-10. PMID 23839199. Link
9. Pratchyapurit WO. Combined use of two formulations containing diacetyl boldine, TGF-β1 biomimetic oligopeptide-68 with other hypopigmenting/exfoliating agents and sunscreen provides effective and convenient treatment for facial melasma. J Cosmet Dermatol. 2016;15(2):131-44. PMID 26833454. Link
10. Lyons A, et al. A Randomized, Double-Blind, Placebo-Controlled, Split-Face Study of the Efficacy of Topical Epidermal Growth Factor for the Treatment of Melasma. J Drugs Dermatol. 2018;17(9):970-973. PMID 30235384. Link
11. Chen T, et al. Tranexamic Acid for the Treatment of Hyperpigmentation and Telangiectatic Disorders Other Than Melasma: An Update. Clin Cosmet Investig Dermatol. 2024;17:2151-2163. PMID 39350932. Link
12. Del Rosario E, et al. Randomized, placebo-controlled, double-blind study of oral tranexamic acid in the treatment of moderate-to-severe melasma. J Am Acad Dermatol. 2018;78(2):363-369. PMID 28987494. Link
13. Calacattawi R, et al. Tranexamic acid as a therapeutic option for melasma management: meta-analysis and systematic review of randomized controlled trials. J Dermatolog Treat. 2024;35(1):2361106. PMID 38843906. Link
14. Wang Q, et al. Combining Microneedling and Tranexamic Acid for Melasma: A Systematic Review and Meta-Analysis. Aesthetic Plast Surg. 2025;49(17):4961-4974. PMID 40555739. Link
15. Mohamed M, et al. Microneedling with glutathione versus microneedling alone in treatment of facial melasma: Split-face comparative study. J Cosmet Dermatol. 2023;22(12):3379-3386. PMID 37313658. Link

This is general information, not medical or legal advice. Rules vary by state and change. Confirm your own facts with counsel.