Apremilast is effective in controlling the progression of adult vitiligo: A case series

Utility of prostaglandin analogues and phosphodiesterase inhibitors as promising last resorts for the treatment of vitiligo: A systematic review, from mechanisms of action to mono-, combination and comparative therapies

BACKGROUND

The treatment of vitiligo is a persistent challenge in dermatology. New treatments are being offered and studied in this field for those resistant to or intolerant of classical therapies.

AIMS

In this systematic review, we study the use of prostaglandin analogues (PGAs) and phosphodiesterase inhibitors (PDEIs) in the treatment of vitiligo, as they are known for their pigmentation inducing effects through activating melanocytes.

METHODS

We searched four main online databases with the keywords "Vitiligo", "Prostaglandin analogue" and "Phosphodiesterase inhibitor".

RESULTS

A total of 42 articles were included, with 1027 cases, studying drugs like bimatoprost, latanoprost, travoprost, dinoprostone, apremilast, crisaborole, etc. Among the included studies, the treatment regimens are commonly once or twice daily for 12-48 weeks, with a mean of 20.61 weeks, and the routes of administration are mainly topical gels or ophthalmic solutions and oral tablets. Side effects are mild and tolerable, namely erythema, itching or burning sensations at application site for topicals, or gastrointestinal problems with apremilast. Repigmentation results are significant in both adult and pediatric patients and progressive or stable vitiligo. PGAs and PDEIs outperform many classical therapies, for example, narrowband ultraviolet B phototherapy (NB-UVB), tacrolimus, mometasone or methylprednisolone mini-pulse. PGAs or PDEIs are usually used in combination therapies to either cause synergism or increase drug delivery, and almost always enhance repigmentation, for example, with NB-UVB, fractional CO2 laser, microneedling, and mometasone.

CONCLUSION

Monotherapy or add-on PGAs and PDEIs can be considered effective treatments for vitiligo and promising last resorts for those resistant to other therapies.

Up-and-Coming Drugs for the Treatment of Vitiligo

Vitiligo is a chronic autoimmune disease that causes depigmented patches on the skin. It affects 0.5%-2.0% of the global population. It goes beyond physical appearance, often leading to stigmatization, low self-esteem, and depression, burdening patients with psychosocial challenges. The pathogenesis of vitiligo involves the loss of melanocytes due to autoreactive CD8+ T cells, triggered by environmental stressors and exacerbated by cellular vulnerabilities and immune responses. The release of danger signals and pro-inflammatory factors initiates an immune cascade perpetuating melanocyte destruction, mainly driven by interferon-γ and the C-X-C motif chemokine ligand 9/10-chemokine receptor 3 axis. Long-lasting tissue-resident memory T cells (Trms) and cytokines contribute to lesion persistence. Current treatments focus on topical steroids and tacrolimus, systemic steroids, and phototherapies, but their efficacy remains suboptimal, necessitating the development of new therapeutic options. Building on recent advancements in understanding the immunological mechanisms in vitiligo pathogenesis, with the initiation of Food and Drug Administration approval of topical ruxolitinib, various potential treatment options such as JAK inhibitors, cytokine blockers, and Trm or regulatory T cell targeting agents are being clinically researched and anticipated for vitiligo based on both preclinical and clinical data. This review aims to categorize and summarize the diverse investigational drugs currently undergoing clinical trials for vitiligo. By examining clinical outcomes, it is anticipated that this review will bring hope to dermatologists and patients regarding vitiligo, a condition that has historically posed challenges and transform it into a realm of potential possibilities.

Vitiligo non-responding lesions to narrow band UVB have intriguing cellular and molecular abnormalities that may prevent epidermal repigmentation

We have discovered that human vitiligo patients treated with narrow-band UVB (NBUVB) demonstrated localized resistance to repigmentation in skin sites characterized by distinct cellular and molecular pathways. Using immunostaining studies, discovery-stage RNA-Seq analysis, and confirmatory in situ hybridization, we analyzed paired biopsies collected from vitiligo lesions that did not repigment after 6 months of NBUVB treatment (non-responding) and compared them with repigmented (responding) lesions from the same patient. Non-responding lesions exhibited acanthotic epidermis, had low number of total, proliferative, and differentiated melanocyte (MC) populations, and increased number of senescent keratinocytes (KCs) and of cytotoxic CD8+ T cells as compared with responding lesions. The abnormal response in the non-responding lesions was driven by a dysregulated cAMP pathway and of upstream activator PDE4B, and of WNT/β-catenin repigmentation pathway. Vitiligo-responding lesions expressed high levels of WNT10B ligand, a molecule that may prevent epidermal senescence induced by NBUVB, and that in cultured melanoblasts prevented the pro-melanogenic effect of α-MSH. Understanding the pathways that govern lack of NBUVB-induced vitiligo repigmentation has a great promise in guiding the development of new therapeutic strategies for vitiligo.

Vitiligo: Pathogenesis and New and Emerging Treatments

Vitiligo is a complex disease with a multifactorial nature and a high impact on the quality of life of patients. Although there are multiple therapeutic alternatives, there is currently no fully effective treatment for this disease. In the current era, multiple drugs are being developed for the treatment of autoimmune diseases. This review assesses the available evidence on the pathogenesis of vitiligo, and a comprehensive review of treatments available for vitiligo now and in the near future is provided. This qualitative analysis spans 116 articles. We reviewed the mechanism of action, efficacy and safety data of phototherapy, afamelanotide, cyclosporine, phosphodiesterase 4 inhibitors, trichloroacetic acid, basic fibroblast growth factor, tumor necrosis factor (TNF) inhibitors, secukinumab, pseudocatalase and janus kinase (JAK) inhibitors. At the moment, there is no clearly outstanding option or fully satisfactory treatment for vitiligo, so it is necessary to keep up the development of new drugs as well as the publication of long-term effectiveness and safety data for existing treatments.

Apremilast Add-On Benefits Over Conventional Drugs (ABCD) in Unstable Non-segmental Vitiligo: A 12-Week Single-Center Randomized Controlled Trial

Background Apremilast is an oral phosphodiesterase-4 enzyme inhibitor that modulates the immune system by increasing intracellular cyclic adenosine monophosphate levels and inhibiting inflammatory cytokines synthesis. We aimed to compare the efficacy and safety of add-on apremilast in combination therapy with standard treatment in patients with unstable, non-segmental vitiligo. Methods The study was a 12-week randomized, controlled, parallel-group, open-labeled trial. The control group received standard treatment (n=15), and the intervention group received 30 mg apremilast twice daily in addition to standard treatment (n= 16). Time to the first sign of re-pigmentation, halt in progression, and change in vitiligo area scoring index (VASI) score is the primary outcomes. Normality was assessed, and appropriate parametric and nonparametric tests were undertaken. Results Thirty-seven participants were randomized into two groups, and analysis was done on thirty-one participants. Over the treatment duration of 12 weeks, the median time to observe the first sign of re-pigmentation was four weeks in the add-on apremilast group compared to seven weeks in the control group (p=0.018). The halt in progression was observed more in the add-on Apremilast group (93.75%) compared to the control group (66.66%) (p=0.08). The VASI score decreased by 1.24 in the add-on apremilast group and 0.05 in the control group (p= 0.754). Parameters including body surface area, dermatology life quality index, and body mass index reduced significantly, while the visual analog scale increased significantly in the add-on apremilast group. However, results were comparable between groups. Conclusions Treatment with add-on apremilast accelerated clinical improvement. It also reduced disease progression and improved the disease index among participants. However, add-on apremilast had a lower tolerability profile than the control group.

Apremilast and narrowband ultraviolet B combination therapy suppresses Th17 axis and promotes melanogenesis in vitiligo skin: a randomized, split-body, pilot study in skin types IV-VI

Improved repigmentation of generalized vitiligo in skin types IV-VI has been reported in clinical response to combined therapy with apremilast and narrowband (NB)-UVB; however, tissue responses to combined therapy versus NB-UVB monotherapy have not been elucidated. We compared the change from baseline in cellular and molecular markers in vitiligo skin after combined therapy versus NB-UVB monotherapy. We assessed lesional and nonlesional skin samples from enrolled subjects and evaluated for immune infiltrates, inflammatory, and melanogenesis-related markers which were compared across different treatment groups. Combined therapy resulted in significant reduction of CD8⁺T cells and CD11c⁺ dendritic cells, downregulation of PDE4B and Th17-related markers, and upregulation of melanogenesis markers. This study was limited to small sample size, skin types IV-VI, and high dropout rate. Our molecular findings support the clinical analysis that apremilast may potentiate NB-UVB in repigmentation of generalized vitiligo in skin types IV-VI.

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.

Successful treatment of vitiligo with crisaborole ointment: a report of two cases

As selective PDE-4 small molecule inhibitor, Crisaborole has been used with success in atopic dermatitis and psoriasis. Here we report two vitiligo patients successfully treated with crisaborole ointment.

Research Progress of Small Molecules as Anti-vitiligo Agents

Vitiligo is a disease characterized by skin discoloration, and no safe and effective drugs have been developed until now. New drug research and development are imminent. This article reviews the research on small-molecule drugs for vitiligo from 1990 to 2021 at home and abroad. They are classified according to their structures and mechanisms of action, including natural products and derivatives, anti-oxidative stress drugs, immunosuppressants, prostaglandins, etc. The research on their anti-vitiligo activity, structural modification, new dosage forms, clinical trials, and the development trend in new anti-vitiligo drugs are reviewed, which provides important references for the development of new drugs.

Updates and new medical treatments for vitiligo (Review)

Vitiligo is a multifactorial disease characterized by the loss of skin pigment, which results in achromic macules and patches. There are currently several medical treatments available, which aim to arrest progression and induce skin repigmentation. These treatments alone or combined have exhibited varying degrees of pigmentation, and the majority are safe and effective. All therapies for vitiligo are limited, and no known treatment can consistently produce repigmentation in all patients. Individualized treatment is appropriate according to the location, clinical presentation and the presence of disease activity. The present review summarizes the medical treatments available for vitiligo: Systemic and topic pharmacological therapies, physical and depigmentation treatments. Several treatments are still underway and have not yet been approved. However, due to the promising preliminary results, these are also mentioned in the present review.

Vitiligo: Translational research and effective therapeutic strategies

This is an exciting phase of vitiligo research with the current understanding of vitiligo pathogenesis and its translation to successful treatment. The pathogenetic origin of vitiligo revolves around autoimmunity with supporting role from many other factors like oxidative stress, inherent melanocyte defects, or defective keratinocytes and fibroblasts. Vitiligo can be classified into segmental or non-segmental depending upon the clinical presentation, or it can be classified as progressing or stable based on the activity of the disease. Vitiligo treatments need to be stratified depending upon which type of vitiligo we are treating and at which phase the vitiligo patient presents to us. There are two different aims of treatment of vitiligo. The first involves rescuing the melanocytes from the damage to arrest the depigmentation. The second strategy focuses on replenishing the melanocytes so that successful repigmentation is achieved. It is also important to maintain the disease in a stable phase or prevent relapse. As stability in non-segmental vitiligo is a dynamic process, maintenance of the stability of repigmentation is also an important consideration in the management of vitiligo. In this review, we shall briefly discuss the current options and future insight into the management of vitiligo.

Phosphodiesterase inhibitors and prostaglandin analogues in dermatology: A comprehensive review

Due to immune-mediated nature, medicines with immunomodulatory and anti-inflammatory effects can used to treat many dermatologic diseases. Phosphodiesterase and prostaglandins are involved in many inflammatory pathways that cause cutaneous disorders. Phosphodiesterase inhibitors (PDEIs) and prostaglandin analogues are currently employed to treat several dermatologic disorders. Given the few comprehensive reviews in this context, focusing on the dermatologic applications and efficacy of these medicines appears valuable. The present comprehensive review was, therefore, performed on the applications of PDEIs and prostaglandin analogues in different cutaneous disorders. All the relevant articles were selected to perform this review by searching databases such as Medline, Google Scholar, Scopus, and Web of Science. Oral PDEIs, especially apremilast, is an effective medicine in psoriasis and a number of other cutaneous disorders such as vitiligo. Topical PDEIs, including crisaborole ointment 2%, is a safe and effective treatment in atopic dermatitis. Prostaglandin analogues, especially their topical forms such as latanoprost and bimatoprost, have different applications in cutaneous disorders, including pigmentary disorders, especially vitiligo and hair repigmentation; for instance, bimatoprost is used for eyelash repigmentation. Prostaglandin analogues are also used in alopecia, including androgenetic alopecia and alopecia areata. Oral (apremilast) and topical (crisaborole) PDEIs and topical prostaglandin analogues, including latanoprost and bimatoprost, were found safe and effective in different skin diseases. In terms of efficiency and safety, these medicines compete with other medications of similar use even with higher efficacy and fewer side effects that necessitate further studies.

Off-Label Therapeutic Potential of Crisaborole

Crisaborole, a topical phosphodiesterase-4 inhibitor, was recently approved in 2016 for the treatment of mild to moderate atopic dermatitis in adults and children greater than 2 years of age. Since that time, several case reports and a small randomized controlled trial have been published regarding the off-label use of crisaborole for the treatment of other inflammatory dermatologic disorders. This paper reviews the current, albeit limited, evidence for off-label use of crisaborole for psoriasis, seborrheic dermatitis, vitiligo, and inflammatory linear verrucous epidermal nevus. Additional potential therapeutic uses for crisaborole are also postulated, based on its mechanism of action. Future studies are required to elucidate the full therapeutic potential of crisaborole; however, it is a welcome addition to the current nonsteroid topical treatments for inflammatory dermatologic disease.

Analytical Methods for Determination of Apremilast from Bulk, Dosage Form and Biological Fluids: A Critical Review

Apremilast is an anti-inflammatory agent. It has been a flourishing molecule in the field of dermatology. In the year 2014, Apremilast got its approval for treatment of psoriatic arthritis. Presently it is known to treat a number of other conditions, including atopic dermatitis and plaque psoriasis. Apremilast a phthalimide derivative, is non-hygroscopic in nature. It is practically insoluble in water. Apremilast acts by inhibiting the activity of phosphodiesterase 4 (PDE4), an intracellular enzyme. Analytical method plays a key role to understand the physio-chemical properties of a drug molecule. Because of poor solubility and low permeability, analytical method development and formulation becomes challenging. Till date, there are no standard test methods available to analyze Apremilast. So, a critical review of the analytical techniques of Apremilast was carried out. The literature search was done by screening the papers reporting analytical techniques of Apremilast from year 2014 to 2019. Methodologies particularly UV spectroscopy, HPTLC, HPLC, X-ray diffraction, NMR, LC-MS were collected and reviewed. Interminable efforts are made by the researchers to develop simple, accurate, robust and cost-effective methods of analysis. In pharmaceutical research, this information will aid in the development of new delivery systems. The review will prove beneficial and advantageous pre-formulation studies and will guide the formulation development.

Effectiveness of topical Nigella sativa for vitiligo treatment

Vitiligo is a pigment disease characterized by the disruption of melanocyte structure and function. Its etiology is unknown; however, genetic predisposition, biochemical factors, and neural mechanisms are thought to be effective. Although many agents are being used for its treatment, generally there is no absolute cure. The aim of the present study is to evaluate the effectiveness of topical Nigella sativa seed oil on vitiligo patients. Thirty-three vitiligo patients were included in the study. Totally 47 areas were evaluated in all patients. Cream containing N sativa seed oil was topically applied to hands, face, and genital region two times a day for 6 months. Statistically significant repigmentation was detected in hands, face, and genital region, the three treatment areas, and the p values are found .005, .001, and .004, respectively. N sativa can be used as an adjuvant therapy that can contribute to the treatment especially in sensitive skin areas like genital region.