BACKGROUND: α-Melanocyte-stimulating hormone (α-MSH) is a melanocortin peptide 
that increases skin pigmentation during ultraviolet light-mediated tanning. As 
α-MSH has been shown to possess anti-inflammatory effects, we assessed the 
clinical potential of a superpotent α-MSH analogue, afamelanotide 
(Nle(4)-D-Phe(7)-α-MSH), in patients with acne vulgaris, the most common 
inflammatory skin disorder.
METHODS: Afamelanotide (16 mg) was given in a phase II open-label pilot study 
subcutaneously as a sustained-release resorbable implant formulation to 3 
patients with mild-to-moderate facial acne vulgaris. Evaluation included lesion 
count, adverse effects and patient-reported outcome. Monitoring of laboratory 
parameters included differential blood counts, electrolytes, urine analysis, and 
liver and kidney function tests. Skin melanin density was measured by 
reflectance spectrophotometry.
RESULTS: The total number as well as the number of inflammatory acne lesions 
declined in all patients 56 days after the first injection of afamelanotide. 
Life quality as measured by Dermatology Life Quality Index likewise improved in 
all 3 patients 56 days after the first injection of afamelanotide. There were no 
adverse effects except mild and short-term fatigue in one patient. All patients 
experienced increased pigmentation especially on the face. Clinically relevant 
changes in laboratory parameters were not detected.
CONCLUSIONS: Afamelanotide appears to have anti-inflammatory effects in patients 
with mild-to-moderate acne vulgaris. Future trials are needed to confirm the 
anti-inflammatory action of this melanocortin analogue in patients with acne 
vulgaris.