Skin Therapy Letter

There is growing awareness of the complex link between nutrition and skin. In the last few decades, our understanding of this link has grown significantly with research findings from multiple laboratory, animal, and human studies. From the impact of diet on clinical features of aging skin, to documentation of the biochemical and histologic changes that occur, our understanding of this link continues to expand and evolve. In this paper, we review the research on the impact of diet on skin aging. A number of long-term observational population studies have documented that healthier diets are linked to fewer signs of skin aging...

Trifarotene 50 μg/g cream is a fourth generation topical retinoid with retinoic acid receptor gamma selectivity. It was recently approved by the US FDA and Health Canada for the topical treatment of facial and truncal acne for those aged 9 and older based on two identically designed phase 3 trials demonstrating superiority in lesion count reduction and global acne improvement compared to vehicle. These studies and a 1 year study also demonstrated safety and tolerability with cutaneous adverse events developing in an anticipated timeframe (1 week) for the face...

The ichthyoses, also termed the disorders of keratinization, are a heterogenous group of skin diseases in which a distinctive horny layer arises secondary to excessive transepidermal water loss. Although occasionally acquired, the majority of ichthyoses are inherited and can be pinpointed to characteristic genetic mutations. Management depends on disease severity and includes topical agents and lifestyle modifications with or without oral retinoids. Genetic counseling is also an important consideration. This review aims to highlight advances in our understanding of disease pathogenesis as well as the holistic approach necessary to adequately manage ichthyosis patients...

HP40 (Eskata™) is a stabilized, topical solution of 40% hydrogen peroxide (H2O2) packaged in an applicator pen that is US FDA-approved to treat seborrheic keratoses (SKs). By harnessing the oxidative capabilities of H2O2 , 1-2 treatments with HP40 produced a higher rate of clearance of four SKs per patient compared to vehicle in two phase 3 trials. The clearance rate was higher for the face than the trunk and extremities. Similarly, the risks of pigmentary changes and scarring from HP40 were lower for the face than other locations...

Methotrexate (MTX), an agent originally intended for anti-neoplastic use, has been successfully employed in the treatment of a variety of dermatologic conditions. In addition to its multiple clinical indications, variable dosing and modes of administration make it a viable option for patients of all ages and most comorbidities. MTX is a folate analog that antagonizes dihydrofolate reductase, thus inhibiting thymidylate synthesis and, ultimately, the production of pyrimidine. Depending on dosage, MTX can function as an anti-inflammatory agent, immunomodulator, or antimetabolite...

Psoriasis is an immune-mediated inflammatory skin condition associated with many comorbidities and poor quality of life. The pathogenesis of psoriasis is complex and involves numerous proinflammatory cytokines. Many biologic therapies have been developed to block the action of these proinflammatory molecules, including inhibitors of tumor necrosis factor (TNF), interleukin (IL)-17, IL-12, and IL-23. IL-23 is composed of two subunits, p19 and p40. The p40 subunit is shared with IL-12, and inhibitors of the p40 subunit can block both IL-12 and IL-23 signaling...

Dermatology supplements, often marketed as “skin, hair, and nail” supplements, are becoming increasingly popular. However, many consumers lack an understanding of the science of dietary supplements or the specifics of the supplement industry. While certain supplements at the right dose in the right population may prove beneficial, the evidence is sparse for many supplements. In addition, the use of some supplements has resulted in serious adverse effects. From a regulatory standpoint, the US FDA recognizes dietary supplements as foods...

Platelet-rich plasma (PRP) is an autologous serum containing high concentrations of platelets and growth factors. PRP continues to evolve as an important treatment modality with many applications in dermatology, particularly in the areas of hair restoration, skin rejuvenation, acne scars, dermal augmentation, and striae distensae. Furthermore, combining PRP with laser therapies, microneedling, dermal fillers, and autologous fat grafting produces synergistic effects, leading to improved aesthetic results. Future studies should standardize PRP treatment protocols for specific indications...

Herpes zoster (HZ), also known as shingles, results from reactivation of the latent varicella-zoster virus (VZV), which commonly causes chickenpox in childhood. Greater than 90% of adults are infected with this virus, putting them at risk for reactivation. HZ presents as a painful, vesicular rash distributed in a unilateral and dermatomal pattern along dorsal root or cranial nerve ganglia. The rash often presents with prodromal symptoms and progresses to include clear vesicular clusters, evolving through stages of pustulation, ulceration, and crusting...

The interleukin (IL)-17 inhibitors have proven to be highly effective in the treatment of psoriasis. The most recently approved agent, brodalumab, had few cases of suicidal behavior, including completed suicide, in the phase 3 clinical program leading both the US FDA and Health Canada to add a boxed warning to its label. This raises the importance of identifying the psychiatric comorbidities associated with psoriasis. It is also necessary to critically examine the data from the brodalumab clinical trial program to determine whether there is enough information to establish causality and whether other factors, other than the drug, could be playing a role...

Epidermolysis bullosa (EB) is a group of rare mucocutaneous fragility disorders often presenting in infancy and early childhood with painful blistering of the skin and mucous membranes. The severity of EB blister burden varies by disease subtype. Studies have shown that patients with generalized severe epidermolysis bullosa simplex (EBS), a variant characterized by extreme fragility, develop blisters in the setting of overproduced, mutated K14 protein, a component of the intermediate filament integral in keratinocyte stability, and constitutive activation of interleukin (IL)-1 , a pro-inflammatory cytokine that promotes the hyperproliferation of keratinocytes...

Vitiligo is an acquired, autoimmune disease characterized by depigmented macules and patches on the skin, which occur secondary to melanocyte destruction. Available therapeutic options are broadly divided into medical, surgical and phototherapy, though treatment of vitiligo can be challenging. Early diagnosis and management can maximize treatment efficacy. The purpose of this discussion is to review updates in the management of vitiligo, including existing and emerging therapies.

Atopic dermatitis is a common cutaneous disease with significant morbidity affecting children and adults. The mainstay of atopic dermatitis therapy has typically included emollients, topical corticosteroids, and topical calcineurin inhibitors. Among the newer advances recently introduced is crisaborole (Eucrisa™), a phosphodiesterase type-4 inhibitor (PDE-4) for the treatment of mild moderate atopic dermatitis. Evidence from phase 3 trials demonstrates crisaborole as an efficacious topical agent with a favorable safety profile and limited systemic exposure...

Hyperhidrosis is a condition characterized by excessive sweat production beyond which is physiologically necessary for thermal regulation. Affecting over 4.8% of the United States population, studies have shown that severe primary hyperhidrosis interferes with daily activities and can be considered intolerable, negatively impacting a patient’s quality of life. Glycopyrronium tosylate is a topical anticholinergic agent that reduces sweat production by blocking the activation of acetylcholine receptors in peripheral sweat glands...

Today, a number of treatment options are now available for metastatic melanoma. Within the last decade, the development of novel immunotherapies for cancer has significantly altered the course of the disease in patients with melanoma. With more patients receiving these potentially life-saving treatments, not only have we learned more about the interplay between the immune system and melanoma, but more importantly, which treatment options are most appropriate given the clinical picture.

Primary focal hyperhidrosis is a relatively common disease that has a significant impact on afflicted patient’s quality of life. The pathogenesis of the disease is thought to stem from increased cholinergic activity on eccrine sweat glands. Topical aluminum chloride based antiperspirants are good first-line agents for all affected body sites. Anticholinergic agents are emerging as effective topical alternatives. Iontophoresis passes an electrical current through the skin and is an excellent treatment option for palmoplantar disease...

Afamelanotide, an α-melanocyte stimulating hormone analogue, has become an emerging therapeutic option for a variety of skin conditions previously refractory to other treatments. Its efficacy has been demonstrated in several dermatologic conditions, including erythropoietic protoporphyria (EPP), solar urticaria, polymorphic light eruption (PMLE), vitiligo, acne, and Hailey-Hailey disease. Its relatively low risk side effect profile makes it an attractive treatment option and also paves the way for innovative use in other disorders...

Cannabinoids have demonstrated utility in the management of cancer, obesity, and neurologic disease. More recently, their immunosuppressive and anti-inflammatory properties have been identified for the treatment of several dermatologic conditions. This review thus assesses the therapeutic potential of phytocannabinoids, endoocannabinoids, and chemically synthetic cannabinoids in the management of cutaneous disease. The PubMed® and Scopus® databases were subsequently reviewed in December 2017 using MeSH and keywords, such as cannabinoid, THC, dermatitis, pruritus, and skin cancer...

Chronic pruritus remains a difficult condition to treat with many non-specific therapeutic options. Recent scientific discoveries have elucidated the physiology associated with pruritus. Combined with clinical and experimental trials with immune-modulatory agents, chronic pruritus now has novel treatment options with known mechanisms of action. This review goes over recent scientific progress in understanding the molecular mechanisms governing pruritus, the cross-talk between the immune and nervous systems that regulate itch, and central nervous pathways and projections affected by itch...

The Pigmented Lesion Assay (PLA) is a gene expression test that helps rule out melanoma and has the potential to reduce the need for surgical biopsies of atypical pigmented skin lesions. Utilizing a new technological platform for the non-invasive profiling of skin, the assay analyzes samples collected from adhesive patches for expression of two key genes (PRAME and LINC00518) known to be overexpressed in melanoma. The test result is binary (positive/negative) based on the detection of one or both genes. PLA positive cases are generally biopsied to establish the histopathologic diagosis, while PLA negative cases are considered for ongoing monitoring...