A pilot study of 1% pimecrolimus cream for the treatment of childhood segmental vitiligo

Vitiligo Treatments: Review of Current Therapeutic Modalities and JAK Inhibitors

Vitiligo is a chronic autoimmune disease characterized by loss of pigment of the skin, affecting 0.5-2% of the population worldwide. It can have a significant impact on patients' quality of life. In recent years, there has been significant progress in our understanding of the pathogenesis of vitiligo. It is believed that vitiligo develops due to a complex combination of genetics, oxidative stress, inflammation, and environmental triggers. Conventional treatments include camouflage, topical corticosteroids, topical calcineurin inhibitors, oral corticosteroids, phototherapy, and surgical procedures, with the treatment regimen dependent on the patient's preferences and characteristics. With increased understanding of the importance of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway in the pathogenesis of vitiligo, treatment has expanded to include the first US FDA-approved cream to repigment patients with vitiligo. This review summarizes our understanding of the major mechanisms involved in the pathogenesis of vitiligo and its most common available treatments.

Pimecrolimus increases the melanogenesis and migration of melanocytes in vitro

Vitiligo is an intriguing depigmentary disorder and is notoriously difficult to be treated. The ultimate goal of vitiligo treatment is to replenish the lost melanocytes by immigration from hair follicle and to restore the normal function of melanogenesis by residual melanocytes. There are two types of topical calcineurin inhibitors called tacrolimus and pimecrolimus, and are recommended as the first-line treatments in vitiligo. Although pimecrolimus is efficacious for the repigmentation of vitiligo, its intrinsic mechanisms have never been investigated in vitro. This research aimed to study the ability of pimecrolimus on stimulating melanogenesis, melanocyte migration and MITF (microphthalmia associated transcription factor) protein expression. Results showed that pimecrolimus at the dosages of 1, 10, 10² nM were neither mitogenic nor cytotoxic to melanocytes. The addition of pimecrolimus at 10, 10² and 10³ nM significantly increased intracellular tyrosinase activity, which was consistent with the elevated content of melanin content at the same concentrations. The peak effect was seen at 72 h in response to 10² nM pimecrolimus. Results of the wound scratch assay and Transwell assays indicate that pimecrolimus is effective in facilitating melanocyte migration on a collagen IV-coated surface. In addition, MITF protein yield reached the highest by pimecrolimus at 10² nM. In brief, pimecrolimus enhances melanin synthesis as well as promotes migration of melanocytes directly, possibly via their effects on MITF protein expression.

Pharmacologic Treatment of Vitiligo in Children and Adolescents: A Systematic Review

BACKGROUND

The true pathogenic mechanism of vitiligo is still unknown. About half of the patients with this disease have onset before the age of 20 years, making it a serious dermatologic disorder in childhood.

OBJECTIVES

The objective of this study was to review the literature in a systematic way and identify the main pharmacologic treatments and outcomes in children and adolescents with vitiligo.

METHODS

Four databases-the National Library of Medicine (MEDLINE-PubMed), Web of Science, Scopus, and Latin American and Caribbean Health Sciences (LILACS)-were used for the search up to January 2015. All electronic search titles, selected abstracts and full-text articles were independently reviewed by a minimum of two reviewers.

RESULTS

There were 15 articles from 13 different countries: 3 were retrospective and 12 were prospective; the number of participants in the studies varied between 9 and 400, ages ranged from 0 to 18 years, and the duration of disease ranged from 1 to 17 years. The most commonly used drugs were tacrolimus alone (or combined with clobetasol), pimecrolimus, corticosteroids, and calcipotriol. Treatment duration ranged from 10 days to 6 months with a topical route of administration.

CONCLUSIONS

The main outcome measurements were morphometric analysis performed using a computer program, hematologic or biochemical change, and photography (predominant). It is unclear which was the most effective treatment for vitiligo, however, it was found that these therapies are all promising in the treatment of the disease. With proper care, disease control and repigmentation, even if partial, can be achieved.