Effects of a superpotent melanotropic peptide in combination with solar UV radiation on tanning of the skin in human volunteers.
Level 2 - randomized trial
Individual randomized controlled phase 1 trials (with small sample sizes)
PubMed 15262693 · doi:10.1001/archderm.140.7.827
What was done
Three phase 1 open-label clinical trials evaluated the safety and tanning effects of subcutaneous melanotan-1 (MT-1) combined with UV radiation. The first trial randomized 8 subjects to MT-1 (0.08 mg/kg per day) or saline for 10 days, followed by neck irradiation with 3 times the minimal erythema dose (MED) of UV-B. The second study evaluated 12 subjects receiving MT-1 (0.16 mg/kg per day for 10 days) with UV-B (0.25-0.75 MED) to the buttock during (n = 7) or after (n = 5) MT-1 administration. The third trial randomized 8 subjects to sunlight alone on half the back or sunlight plus MT-1 (0.16 mg/kg for 5 days per week for 4 weeks).
What was found
In the first study, 3 of 4 MT-1 subjects achieved tanning, and MT-1 recipients had 47% fewer sunburn cells at the irradiated neck site compared to controls. In the second study, higher-dose MT-1 resulted in more darkened skin sites. In the third study, MT-1 significantly enhanced back tanning, which persisted at least 3 weeks longer than controls; sunlight-only controls required 50% more sun exposure time for equivalent tanning. Side effects were minor (nausea and transient facial flushing) with no pathologic findings at UV-exposed sites.
Why it matters
This study provides early phase 1 evidence that MT-1 can act synergistically with UV radiation to increase skin tanning and reduce sunburn cell formation in humans.
Limits
The trials had very small sample sizes across all cohorts (total n = 28), used an open-label design, and did not report exact p-values, confidence intervals, or skin phototypes in the abstract. Long-term safety was not evaluated.
Cited by
- supports Melanotan II is a melanocortin receptor agonist that stimulates skin tanning in response to minimal UV exposure.