Phototherapy: The vitiligo management pillar

Vitiligo: advances in pathophysiology research and treatment development

The autoimmune condition vitiligo, characterized by skin depigmentation, presents challenges for effective treatment design, with Janus kinase (JAK) inhibitors and other repurposed drugs offering a promising strategy for symptom management. This review explores advantages and shortcomings of current therapies, while presenting the urgent need for further innovative approaches. We emphasize the growing understanding of autoimmune involvement in vitiligo, highlighting several novel treatment avenues including relieving melanocyte stress, preventing dendritic cell activation, halting T cell migration, and suppressing inflammation and autoimmunity. Integrating psychodrama therapy to remediate stress alongside medical interventions marks a holistic approach to enhance patient well-being. The molecular underpinnings of vitiligo care are covered, emphasizing exciting advances revolutionizing vitiligo treatment and improving the quality of life for affected individuals.

Phototherapy for vitiligo: A narrative review on the clinical and molecular aspects, and recent literature

BACKGROUND

Vitiligo is characterized by depigmented patches resulting from loss of melanocytes. Phototherapy has emerged as a prominent treatment option for vitiligo, utilizing various light modalities to induce disease stability and repigmentation.

AIMS AND METHODS

This narrative review aims to explore the clinical applications and molecular mechanisms of phototherapy in vitiligo.

RESULTS AND DISCUSSION

The review evaluates existing literature on phototherapy for vitiligo, analyzing studies on hospital-based and home-based phototherapy, as well as outcomes related to stabilization and repigmentation. Narrowband ultra-violet B, that is, NBUVB remains the most commonly employed, studied and effective phototherapy modality for vitiligo. Special attention is given to assessing different types of lamps, dosimetry, published guidelines, and the utilization of targeted phototherapy modalities. Additionally, the integration of phototherapy with other treatment modalities, including its use as a depigmenting therapy in generalized/universal vitiligo, is discussed. Screening for anti-nuclear antibodies and tailoring approaches for non-photo-adapters are also examined.

CONCLUSION

In conclusion, this review provides a comprehensive overview of phototherapy for vitiligo treatment. It underscores the evolving landscape of phototherapy and offers insights into optimizing therapeutic outcomes and addressing the challenges ahead. By integrating clinical evidence with molecular understanding, phototherapy emerges as a valuable therapeutic option for managing vitiligo, with potential for further advancements in the field.

Comparing the efficacy of 308-nm light-emitting diode and 308-nm excimer lamp for treating vitiligo: A randomized controlled trial

BACKGROUND

In previous studies, the 308-nm light-emitting diode (LED) has been proven safe and effective for treating vitiligo. However, direct comparisons between the 308-nm LED and 308-nm excimer lamp (308-nm MEL) for the treatment of vitiligo are lacking.

OBJECTIVE

To compare the efficacy of the 308-nm LED and 308-nm MEL for treating nonsegmental stable vitiligo.

PATIENTS AND METHODS

This randomized controlled trial was conducted between January 2018 and August 2023. Enrolled patients were randomly assigned to either the 308-nm LED or the 308-nm MEL groups, both receiving 16 treatment sessions. Adverse events that occurred during the treatment were documented.

RESULTS

In total, 269 stable vitiligo patches from 174 patients completed the study. A total of 131 lesions were included in the 308-nm LED group, and 138 lesions were included in the 308-nm MEL group. After 16 treatment sessions, 38.17% of the vitiligo patches in the 308-nm LED group achieved repigmentation of at least 50% versus 38.41% in the 308-nm MEL group. The two devices exhibited similar results in terms of efficacy for a repigmentation of at least 50% (p = .968). The incidence of adverse effects with the two phototherapy devices was comparable (p = .522).

CONCLUSIONS

Treatment of vitiligo with the 308-nm LED had a similar efficacy rate to the 308-nm MEL, and the incidence of adverse effects was comparable between the two devices.

Worldwide expert recommendations for the diagnosis and management of vitiligo: Position statement from the international Vitiligo Task Force-Part 2: Specific treatment recommendations

BACKGROUND

The treatment of vitiligo can be challenging. Up-to-date agreed consensus recommendations on the use of topical and systemic therapies to facilitate the clinical management of vitiligo are currently lacking.

OBJECTIVES

To develop internationally agreed-upon expert-based recommendations for the treatment of vitiligo.

METHODS

In this consensus statement, a consortium of 42 international vitiligo experts and four patient representatives participated in different online and live meetings to develop a consensus management strategy for vitiligo. At least two vitiligo experts summarized the evidence for different topics included in the algorithms. A survey was then given to a core group of eight experts to resolve the remaining issues. Subsequently, the recommendations were finalized and validated based on further input from the entire group during two live meetings.

RESULTS

The recommendations provided summarize the latest evidence regarding the use of topical therapies (steroids, calcineurin inhibitors and Jak-inhibitors) and systemic therapies, including steroids and other systemic immunomodulating or antioxidant agents. The different modalities of phototherapies (NB-UVB, photochemotherapy, excimer devices and home phototherapy), which are often combined with other therapies, are also summarized. Interventional approaches as well as depigmentation strategies are presented for specific indications. Finally, the status of innovative and targeted therapies under development is discussed.

CONCLUSIONS

This international consensus statement culminated in expert-based clinical practice recommendations for the treatment of vitiligo. The development of new therapies is ongoing in vitiligo, and this will likely improve the future management of vitiligo, a disease that still has many unmet needs.

Efficacy of narrow band UVB with or without OMP in stabilization of vitiligo activity in skin photo-types (III-V): A double-blind, randomized, placebo-controlled, prospective, multicenter study

BACKGROUND

NB-UVB has long been the vitiligo management pillar with capability of achieving the main treatment outcomes; repigmentation and stabilization. Its stabilizing effect in dark skin has been debatable. However, randomized controlled trials regarding NB-UVB ability to control disease activity are lacking.

PURPOSE

To assess stabilizing effect of NB-UVB in comparison to systemic corticosteroids, the mainstay in vitiligo stabilization, in skin photo-types (III-V).

METHODS

This is a multicenter, placebo-controlled, randomized, prospective study. Eighty patients with active nonsegmental vitiligo (NSV) (Vitiligo disease activity (VIDA) ≥2) were randomized to either NB-UVB and placebo (NB-placebo) or NB-UVB and dexamethasone oral mini-pulse (OMP) therapy (NB-OMP) for 6 months. Sixty four patients completed the study, 34 in the NB-OMP group and 30 in the NB-placebo group. Patients were evaluated fortnightly according to presence or absence of symptoms/signs of activity.

RESULTS

In spite of earlier control of disease activity observed in the NB-OMP group, it was comparable in both groups by the end of the study period. Disease activity prior to therapy, but not extent, was found to influence control of activity in both groups. Thus, NB-UVB is a safe sole therapeutic tool in vitiligo management. Not only does it efficiently achieve repigmentation, but also it is a comparable stabilizing tool for systemic corticosteroids in spite of slightly delayed control.

CONCLUSION

NB-UVB is the only well-established vitiligo therapy that can be used solely whenever corticosteroids are contraindicated or immune-suppression is unjustified. Nonetheless, its combination with corticosteroids expedites response and improves compliance.

Deciphering skin re-pigmentation patterns in vitiligo: an update on the cellular and molecular events involved

Current treatment of vitiligo is still a great challenge, since most cases of vitiligo have variable re-pigmentation outcomes due to their unpredictable responses to existing therapeutic regimens. There is an urgent need to identify this re-pigmentation process and to develop novel therapies. This review illustrates the most current research and latest understanding of vitiligo skin re-pigmentation and related regulatory mechanisms. Literature was collected from PubMed until January 2020, using the search terms including "vitiligo," "re-pigmentation," "phototherapy," "narrow-band ultraviolet B, " "excimer," "fractional carbon dioxide laser," and "melanocyte stem cells." Literature was mainly derived from English articles. Article type was not limited. Emerging evidence suggests that patients with vitiligo present various re-pigmentation patterns following ultraviolet B phototherapy, which relies on different cell reservoirs from the perilesional margins and/or from uninvolved hair follicles to replenish functional melanocytes that are lost in vitiliginous skin. The following events are likely to be involved in this re-pigmentation process, including: 1) changes in the paracrine secretion and distribution of transforming growth factor-β1 in the bulge area and in the epidermis; 2) the enhanced transfer of dermal pro-melanogenic growth factors to the epidermis; and 3) the induction of a C-X-C motif chemokine ligand (CXCL) 12-enriched micro-environment that efficiently recruits CXCR4- or CXCR7-positive melanocytes. Ongoing studies on the cellular and molecular events underlying vitiligo re-pigmentation will help design new therapeutic strategies to improve treatment outcomes.

Role of the p53‑TRPM1/miR‑211‑MMP9 axis in UVB‑induced human melanocyte migration and its potential in repigmentation

Clinical studies have proven that ultraviolet B (UVB) based phototherapy can induce perifollicular and marginal repigmentation patterns in the skin of vitiligo patients. It is, however, difficult to conceive how melanocytes can easily exit from their tightly interconnected epidermal microenvironment to re‑enter a different location in the skin to establish a new network with neighboring keratinocytes. While it is known that matrix metalloprotease 9 (MMP9) is involved in the degradation of the extracellular matrix in physiological or pathological processes, little is known about whether MMP9 affects melanocyte migration in vitiligo repigmentation. To investigate the effects of the p53‑ transient receptor potential cation channel subfamily M member 1 (TRPM1)/microRNA (miR/miRNA)‑211‑MMP9 axis to regulate melanocyte migration following exposure to UVB, the expression profile of MMP9 in cultured human melanocytes transfected with or without the miR‑211‑mimic and p53‑GFP lentiviral vector, respectively were determined. Quantitative polymerase chain reaction and western blotting were used to examine p53, TRPM1 and MMP9 mRNA and protein levels in UVB‑exposed and unexposed cells. The capacity of melanocytes to migrate on collagen IV substrate was estimated using a Transwell migration assay. Interestingly, the upregulation of p53 and MMP9 at the mRNA and protein levels was evident in melanocytes treated with single or repeat exposures to UVB, whereas levels of TRPM1 and miR‑211 were significantly suppressed in UVB‑exposed melanocytes compared with the UVB‑unexposed control cells. These results indicate that the p53‑TRPM1/miR‑211‑MMP9 axis is significantly activated in melanocytes exposed to UVB. Notably, the ability of melanocyte migration was altered by the overexpression of p53 using a lentiviral vector and by the upregulation of miR‑211 using an miRNA mimic. That altered migration could be neutralized by co‑treatment with GM6001 (a broad‑spectrum MMP inhibitor). Overall, these results show that the MMP9‑mediated migration of melanocytes is regulated by a novel mechanism driven by the p53‑TRPM1/miR‑211‑MMP9 axis. Activation of the p53‑TRPM1/miR‑211‑MMP9 axis potentially represents an attractive therapeutic target to improve repigmentation outcomes in vitiligo patients.

Safety of the current drug treatments for vitiligo

Introduction: Vitiligo is an acquired depigmenting skin disorder adversely affecting the patient's quality of life. Despite the presence of several treatment modalities, ranging from medical to physical to surgical options, none is curative. Each modality has its own drawbacks and side effects. Thus, the treatment modality needs to be tailored for each individual patient taking into consideration the disease characteristics and also its efficacy and safety to obtain a favorable risk-benefit ratio.Areas covered: This review highlights the different treatment modalities utilized in vitiligo up until 4 November 2019 along with their adverse effects and contraindications, if any.Expert opinion: All the medications have their own adverse effects and contraindications. We have included the most commonly used topical corticosteroids, which may result in striae, cutaneous atrophy, and tachyphylaxis, to the recently introduced biologics, which may induce hypersensitivity reactions, systemic toxicities, and even malignancies. However, more long-term studies are needed to assess the safety of these medications, especially the newer ones, to provide a safe and effective treatment for this disorder.

Therapeutic effects of iNOS inhibition against vitiligo in an animal model

Nitric oxide (NO) is involved in several biological processes, but its role in human melanogenesis and vitiligo need further studies. Previous studies revealed that exposure to UVA and UVB were capable of the inducing nitric oxide production in keratinocytes and melanocytes through the activation of constitutive nitric oxide synthase, whereas inducible nitric oxide synthase overexpression has been reported to play an important role in hyperpigmentary disorders. The aim of this study was to evaluate iNOS inhibitor aminoguanidine (AG) as a therapeutic agent in our mouse model of vitiligo. In this study, male C57BL/6J Ler-vit/vit mice were purchased to evaluate the effect of iNOS inhibitor (aminoguanidine) (50 and 100 mg/kg) and L-arginine (100 mg/kg) in a mouse model of vitiligo induced by monobenzone 40%. Moreover, we used phototherapy device to treat the mice with NBUVB as a gold standard.The findings revealed that monobenzone was capable of inducing depigmentation after 6 weeks. However, aminoguanidine in combination with monobenzone was decrease the effect of monobenzone, while L-arginine play a key role in promoting the effect of monobenzone (P<0.001). Based on the phototherapy, the efficacy of phototherapy significantly increased by adding L-arginine (P<0.05). Taken together, we suggest that iNOS inhibitor can be a novel treatment for the prevention and treatment of vitiligo by combination of NBUVB therapy, furthermore; NO agents like L-arginine could also increase the effectiveness of phototherapy. Taken together, this pilot study showed significant repigmentation of vitiligous lesions treated with iNOS inhibitor plus NBUVB therapy, where other aspect including expression of an inducible iNOS, NO and TNF levels remained to be evaluated in mice model.

Home phototherapy for patients with vitiligo: challenges and solutions

Vitiligo is a chronic autoimmune condition involving selective dysfunction and destruction of melanocytes in the skin, hair, or both. The typical presentation is well-demarcated depigmented skin patches. Given vitiligo is the most common cause of depigmentation worldwide and early disease responds best to treatment, prompt diagnosis and proactive management of vitiligo are critical. While a wide variety of treatments has demonstrated variable effectiveness in treating vitiligo, phototherapy remains standard of care because of its proven efficacy and favorable side effect profile. However, many patients with vitiligo are unable to access affordable, consistent, or convenient phototherapy. To address these issues, home-based phototherapy has emerged as a patient-centered alternative. The purpose of this review is to discuss management of vitiligo with a specific focus on access to home-based phototherapy (HBPT) for patients with this condition. Key challenges to HBPT include misperceptions around safety and efficacy, inadequate physician education and training, insurance and financial barriers, and appropriate patient selection. Solutions to these challenges are presented, such as approaches to improve physician education and increasing the evidence surrounding the effectiveness and safety of this treatment for vitiligo. In addition, various practical considerations are discussed to guide dermatologists on how to approach HBPT as a treatment option for patients with vitiligo.