J.TOH1, A. JHINGAN1, S. Y. CHUAH1, W. S. CHONG1, S. THNG1
National Skin Centre1
Afamelanotide, a potent α–melanocyte-stimulating hormone (α-MSH) analogue, has been reported to treat vitiligo effectively by inducing skin tanning. We aim to evaluate the efficacy and safety of combination treatment with afamelanotide implants and narrowband ultraviolet B phototherapy (NB-UVB) in Asian patients with nonsegmental vitiligo.
This study was performed in a tertiary dermatology centre in Singapore. In phase 1, eight patients were enrolled into two-arm, randomized, double-blind study (afamelanotide implants plus NB-UVB versus placebo implants plus NB-UVB). In phase 2, thirteen patients were enrolled into a single-arm, open-label study. Afamelanotide 16 mg implants were administered subcutaneously every 28 days and NB-UVB was administered twice weekly for seven months. Pooled analysis of the efficacy data for all 18 subjects who received combination therapy was conducted.
Combination therapy (n=18) is superior to placebo with statistically significant decrease in median Vitiligo Area Scoring Index (VASI) scores for total, head and neck, hands, upper extremities, trunk and lower extremities at Day 140 and thereafter (p-values<0.05). Onset of repigmentation are observed the earliest for upper extremities and trunk (median 10.5 and 13 days respectively) and the latest for hands and feet (median 36 days for both). Combination therapy is well tolerated.
Afamelanotide may potentiate repigmentation effects of NB-UVB by boosting melanoblast differentiation and melanocortin-1 receptor upregulation. Concomitant afamelanotide administration can reduce NB-UVB dose and potential adverse effects. Our study suggests that administration of subcutaneous afamelanotide implants to vitiligo patients receiving NB–UVB may enhance rates and total surface area of repigmentation, with short-term safety profile.