New and Emerging Therapies for Pediatric Atopic Dermatitis

Dupilumab Treatment in Pediatric Patients Aged 6-11 Years with Severe Atopic Dermatitis Whose Disease Is Not Adequately Controlled: A Review

Atopic dermatitis (AD) is the most common inflammatory skin disease in children. Children with severe AD have a multidimensional disease burden characterized by skin lesions, itching, frequent infections, sleep deprivation, and a high rate of comorbidities. These impact the mental health and overall quality of life of not only the children but also of their parents and caregivers. There are few effective available treatment options for young children with severe AD that are suitable for long-term use. Due to their adverse effects, practice guidelines consider systemic agents inappropriate for this age group, although they are still used off-label in extreme cases. The biologic dupilumab has recently been approved for children aged 6-11 years with severe (EU) and moderate-to-severe (USA) AD, offering hope to this population of patients with a high unmet clinical need. The purpose of this review is to describe the unmet needs of AD patients aged 6-11 years prior to dupilumab approval and to summarize existing clinical data supporting dupilumab's safety and efficacy in these children.

WLJP-025p, a homogeneous Lonicera japonica polysaccharide, attenuates atopic dermatitis by regulating the MAPK/NFκB/AP-1 axis via Act1

Atopic dermatitis (AD) is usually treated with steroids, but long-term use is not an effective cure because side effects and disease aggravation. Therefore, more effective and safer treatments are needed. Using dexamethasone as the positive control, the mechanism of action of water-extracted homogeneous honeysuckle Lonicera japonica polysaccharide (WLJP-025p) to alleviate AD was studied. Mice were administered 2,4-dinitrochlorobenzene in their bare back and right ear to mimic an AD model. The efficacy of WLJP-025p in AD was assessed by measuring right ear thickness and skin lesion scores, pathological observation (haematoxylin-eosin and toluidine blue staining), and serum IgE and IL-1β concentrations. The expression of relevant genes and proteins in the serum and back skin was detected using RT-qPCR, ELISA, western blotting, and immunofluorescence. Molecular docking and dynamic simulation of WLJP-025p and Act1 were performed. WLJP-025p considerably alleviated skin hyperplasia and pathological abnormalities in AD mice and inhibited the expression of Act1, Nucleus-P65, Nucleus-AP-1, and MAPK-related proteins in skin tissues. WLJP-025p formed a stable conformation with Act1, inhibited splenic Th17 differentiation, IL-17 release, and upregulated the expression of related skin barrier proteins. In conclusion, WLJP-025p affects the inflammation regulation via the MAPK/NFκB/AP-1 axis by binding to Act1, promotes the recovery of epithelial barrier function, and alleviates AD in mice.

Interactions between Malassezia and New Therapeutic Agents in Atopic Dermatitis Affecting Skin Barrier and Inflammation in Recombinant Human Epidermis Model

Several studies have reported the pathogenic role of Malassezia in atopic dermatitis (AD); the significance of Malassezia’s influence on AD needs to be further investigated. Dupilumab, a monoclonal antibody to anti-Interleukin (IL) 4Rα, and ruxolitinib, a Janus kinase (JAK)1/2 inhibitor, are the first approved biologics and inhibitors widely used for AD treatment. In this study, we aimed to investigate how Malassezia Restricta (M. restricta) affects the skin barrier and inflammation in AD and interacts with the AD therapeutic agents ruxolitinib and anti-IL4Rα. To induce an in vitro AD model, a reconstructed human epidermis (RHE) was treated with IL-4 and IL-13. M. restricta was inoculated on the surface of RHE, and anti-IL4Rα or ruxolitinib was supplemented to model treated AD lesions. Histological and molecular analyses were performed. Skin barrier and ceramide-related molecules were downregulated by M. restricta and reverted by anti-IL4Rα and ruxolitinib. Antimicrobial peptides, VEGF, Th2-related, and JAK/STAT pathway molecules were upregulated by M. restricta and suppressed by anti-IL4Rα and ruxolitinib. These findings show that M. restricta aggravated skin barrier function and Th2 inflammation and decreased the efficacy of anti-IL4Rα and ruxolitinib.

Epicutaneous Sensitization and Food Allergy: Preventive Strategies Targeting Skin Barrier Repair-Facts and Challenges

Food allergy represents a growing public health and socio-economic problem with an increasing prevalence over the last two decades. Despite its substantial impact on the quality of life, current treatment options for food allergy are limited to strict allergen avoidance and emergency management, creating an urgent need for effective preventive strategies. Advances in the understanding of the food allergy pathogenesis allow to develop more precise approaches targeting specific pathophysiological pathways. Recently, the skin has become an important target for food allergy prevention strategies, as it has been hypothesized that allergen exposure through the impaired skin barrier might induce an immune response resulting in subsequent development of food allergy. This review aims to discuss current evidence supporting this complex interplay between the skin barrier dysfunction and food allergy by highlighting the crucial role of epicutaneous sensitization in the causality pathway leading to food allergen sensitization and progression to clinical food allergy. We also summarize recently studied prophylactic and therapeutic interventions targeting the skin barrier repair as an emerging food allergy prevention strategy and discuss current evidence controversies and future challenges. Further studies are needed before these promising strategies can be routinely implemented as prevention advice for the general population.

Blockage of the IL-31 Pathway as a Potential Target Therapy for Atopic Dermatitis

Atopic dermatitis (AD), a pruritic, inflammatory chronic disease with multifactorial pathogenesis, has been a therapeutic challenge. Novel target treatments aim to reduce not only the immunologic dysfunction and microbiome dysbiosis but also the recovery of the damaged skin barrier. The current review focuses on the interleukin 31 (IL-31) pathway and AD and offers an overview of the current clinical studies with monoclonal antibodies blocking this cascade. Pruritus, the key symptom of AD, has substantial participation of the IL-31 complex and activation of relevant signaling pathways. Epidermal keratinocytes, inflammatory cells, and cutaneous peripheral nerves express the interleukin-31 receptor α-chain (IL-31RA), upregulated by Staphylococcus aureus toxins or Th2 cytokines involved in AD. Nemolizumab is a humanized monoclonal antibody that antagonizes IL-31RA, inhibiting the IL-31 cascade and therefore contributing to reducing the pruritus and inflammation and recovering the damaged skin barrier in AD patients. Phases 2 and 3 clinical trials with nemolizumab in AD show a suitable safety profile, with a fast, efficient, and sustained reduction of pruritus and severity scores, especially when associated with topical treatment. Deciphering the full interplay of the IL-31 pathway and AD may expand the potential of nemolizumab as a targeted therapy for AD and other pruritic conditions.

Review of Ruxolitinib in the Treatment of Atopic Dermatitis

OBJECTIVE

To review the pharmacokinetics, efficacy, and safety of a newly approved topical Janus kinase 1 (JAK) inhibitor, ruxolitinib (RUX), in patients with atopic dermatitis (AD).

DATA SOURCES

A literature search was completed May 1, 2022. The term RUX and AD was queried in MEDLINE (PubMed) and EMBASE databases.

STUDY SELECTION AND DATA EXTRACTION

Peer-reviewed articles written in English and published prior to May 1, 2022 were included.

DATA SYNTHESIS

In the phase II clinical trial, more patients treated with 1.5% topical RUX twice a day had a mean percentage improvement in Eczema Area and Severity Index (EASI) scores from baseline to 4 weeks, when compared to vehicle (71.6% vs 15.5%; P < 0.001). In phase III clinical trials, greater percentage of patients who received 0.75% topical RUX (TRuE-AD1 50.0% and TRuE-AD2 39.0%) or 1.5% topical RUX (TRuE-AD1 53.8% and TRuE-AD2 51.3%) achieved an Investigator's Global Assessment (IGA) score of 0 (clear) or 1 (almost clear) and had a ≥2-grade improvement from baseline to 8 weeks, when compared to vehicle (TRuE-AD1 15.1% and TRuE-AD2 7.6%; P < 0.001).

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Atopic dermatitis is a highly prevalent long-term inflammatory skin condition. Pruritus is the main contributor of decreased quality of life in patients with AD. Topical RUX inhibits JAK1 and JAK2 producing antiinflammatory and antipruritic effects. Patients experienced a reduction in pruritus within 2 days. This decreased pruritus translated to increased quality of life and less sleep disturbances.

CONCLUSION

Data from phase II and III clinical trials in adult patients suggest RUX is an effective and safe therapy for AD.

Advances in Current Drugs and Formulations for the Management of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disease with a complex pathophysiology. Treatment of AD remains challenging owing to the presence of a wide spectrum of clinical phenotypes and limited response to existing therapies. However, recent genetic, immunological, and pathophysiological insights into the disease mechanism resulted in the invention of novel therapeutic drug candidates. This review provides a comprehensive overview of current therapies and assesses various novel drug delivery strategies currently under clinical investigation. Further, this review majorly emphasizes on various topical treatments including emollient therapies, barrier repair agents, topical corticosteroids (TCS), phosphodiesterase 4 (PDE4) inhibitors, calcineurin inhibitors, and Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway inhibitors. It also discusses biological and systemic therapies, upcoming treatments based on ongoing clinical trials. Additionally, this review scrutinized the use of pharmaceutical inactive ingredients in the approved topical dosage forms for AD treatment.

New and Upcoming Topical Treatments for Atopic Dermatitis: A Review of the Literature

Atopic dermatitis (AD) is a chronic inflammatory dermatosis with periods of exacerbation and remissions. AD is characterized by intense, persistent pruritus and heterogeneity in clinical symptomatology and severity. Therapeutic goals include the amelioration of cutaneous eruptions, diminishing relapses and eventually the disease burden. To date, topical corticosteroids (TCS) and calcineurin inhibitors (TCI) have yet been deemed the mainstay of topical treatments in AD management. Nevertheless, despite their indisputable efficiency, TCS and TCI are not indicated for continuous long-term use given their safety profile. While research in AD has concentrated predominantly on systemic therapies, more than 30 novel topical compounds are under development. The existing data appear encouraging, with some regimens that are already FDA-approved (ruxolitinib was the most recent in September 2021) and several pharmaceutical pipeline products for mild-to-moderate AD that are in an advanced stage of development, such as tapinarof, difamilast and roflumilast. Larger, long-term studies are still required to evaluate the efficacy and safety of these novel compounds in the long run and weigh their advantages over present treatments. In this review, we aim to provide an overview of the latest knowledge about AD topical treatments, echoing upcoming research trends.

Nemolizumab: First Approval

Nemolizumab is a subcutaneously administered humanized anti-interleukin-31 (IL-31) receptor A (IL-31RA) monoclonal antibody that is being developed by Chugai Pharmaceutical Co. Ltd, Maruho Co. Ltd and Galderma Pharma S.A. for the treatment of skin diseases, including atopic dermatitis (AD), AD associated pruritus (ADaP), prurigo nodularis (PN), chronic kidney disease associated pruritus (CKDaP) and systemic sclerosis (SSc). IL-31 is a neuroimmune cytokine that induces itch, inflammation, keratinocyte differentiation and fibroblast activation in chronic pruritic skin diseases. Nemolizumab (Mitchga^® Syringes) was approved in Japan on 28 March 2022 for use in adults and children over the age of 13 years for the treatment of itch associated with AD (only when existing treatment is insufficiently effective). This article summarizes the milestones in the development of nemolizumab leading to this first approval.

Recent Developments and Advances in Atopic Dermatitis: A Focus on Epidemiology, Pathophysiology, and Treatment in the Pediatric Setting

Atopic dermatitis (AD) is a chronic inflammatory skin disorder that affects a substantial number of children and has a significant negative impact on affected patients and their caregivers/families. Recent studies have led to significant evolutions in the understanding of AD pathogenesis, epidemiology, and treatment. The first point of contact for many patients with new-onset AD is usually with their primary care provider or pediatrician. This underscores the importance for pediatricians to understand the basic pathophysiology and current standards of care for AD. This article provides up-to-date information and reviews the basic principles of AD pathophysiology, diagnosis, and management. In addition, the article highlights recent advances in scientific research regarding the mechanisms involved in the pathogenesis of atopic dermatitis that have resulted in the discovery of novel therapeutic targets and the development of targeted biologic therapies with the potential to revolutionize AD therapy.

Emerging topical drug delivery approaches for the treatment of Atopic dermatitis

BACKGROUND

Atopic dermatitis is a chronic, relapsing skin inflammation disease that generally affects 20% of children and 1-3% of adults. It is characterized by pruritus, inflammatory skin lesions, and skin barrier defect. The pillar treatment is topical therapies that have shown great adherence and incredible results in alleviating symptoms of atopic dermatitis. Topical corticosteroids and calcineurin inhibitors have shown improvement in the symptoms of atopic dermatitis but have certain side effects. There is need to develop new therapies or novel drug delivery approaches which can overcome drawbacks of the conventional formulation and increase the therapeutic efficacy.

AIM

The scope of this review is to describe the new topical therapies including phosphodiesterase inhibitors, Janus kinase inhibitors, and nano-formulations such as nanoemulsion, polymeric and lipid nanoparticles, vesicular system, and micelles.

METHODS

The article reviews and discusses the published literature of the topical drug delivery approaches for treatment of Atopic dermatitis.

RESULTS

The reported literature highlighted the benefits of novel topical formulations exhibiting targeted drug delivery, better penetration, enhanced therapeutic efficacy, and overcome systemic side effects.

CONCLUSION

Literature indicated that the new therapies and novel drug delivery approaches found to be the therapeutically more effective in increasing the efficacy of drugs and reducing the side effects in comparison with the conventional treatments for Atopic dermatitis. This has provided a way to modify and develop more such formulations for dermal delivery.

The Posology of Dupilumab in Pediatric Patients With Atopic Dermatitis

Dupilumab demonstrated efficacy with an acceptable safety profile in two randomized, double-blind, placebo-controlled, parallel-group, phase III trials in adolescents (12-17 years; LIBERTY AD ADOL) and children (6-11 years; LIBERTY AD PEDS) with atopic dermatitis (AD) treated for 16 weeks. Here, we present the pharmacokinetic profiles and exposure-response (E-R) relationships of dupilumab that guided the posology in these populations. A total of 251 adolescent patients with moderate-to-severe AD were randomized to subcutaneous dupilumab monotherapy every 2 weeks (q2w; 200 mg q2w, baseline weight < 60 kg; 300 mg q2w, ≥ 60 kg), dupilumab 300 mg every 4 weeks (q4w; non-weight tiered), or placebo; 367 children with severe AD were randomized to dupilumab q2w (100 mg q2w, baseline weight < 30 kg; 200 mg q2w, ≥ 30 kg), dupilumab 300 mg q4w, or placebo. Children received concomitant topical corticosteroids in addition to dupilumab, and loading doses were administered at the start of therapy. Mean dupilumab trough concentrations at week 16 for weight subcategories in each dosing regimen were compared with adult exposures for the approved dupilumab 300 mg q2w regimen. Positive E-R relationships were demonstrated between dupilumab trough concentrations and AD outcome measures across patient populations and regimens; no relationship was observed with treatment-emergent conjunctivitis. Based on these analyses, a weight-tiered posology was proposed for adolescents (200/300 mg q2w in patients 30-< 60 kg/≥ 60 kg) and children (300 mg q4w in patients 15-< 30 kg, 200 mg q2w in patients 30-< 60 kg) with moderate-to-severe AD.

Huangbai Liniment Ameliorates Skin Inflammation in Atopic Dermatitis

Atopic dermatitis (AD), also known as atopic eczema, is one of the most common skin diseases and is characterized by allergic skin inflammation, redness, and itchiness and is associated with a hyperactivated type 2 immune response. The leading causes of AD include an imbalance in the immune system, genetic predisposition, or environmental factors, making the development of effective pharmacotherapies complex. Steroids are widely used to treat AD; however, they provide limited efficacy in the long term and can lead to adverse effects. Thus, novel treatments that offer durable efficacy and fewer side effects are urgently needed. Here, we investigated the therapeutic potential of Huangbai Liniment (HB), a traditional Chinese medicine, using an experimental AD mouse model, following our clinical observations of AD patients. In both AD patient and the mouse disease model, HB significantly improved the disease condition. Specifically, patients who received HB treatment on local skin lesions (3–4 times/day) showed improved resolution of inflammation. Using the 1-Chloro-2,4-dinitrobenzene (DNCB)-induced AD model in BALB/c mice, we observed that HB profoundly alleviated severe skin inflammation and relieved the itching. The dermatopathological results showed markedly reversed skin inflammation with decreased epidermal thickness and overall cellularity. Correspondingly, HB treatment largely decreased the mRNA expression of proinflammatory cytokines, including IL-1β, TNF-α, IL-17, IL-4, and IL-13, associated with declined gene expression of IL-33, ST2, and GATA3, which are connected to the type 2 immune response. In addition, HB restored immune tolerance by promoting regulatory T (T_REG) cells and inhibiting the generation of T_H1, T_H2, and T_H17 cells in vitro and in the DNCB-induced AD mouse model. For the first time, we demonstrate that HB markedly mitigates skin inflammation in AD patients and the DNCB-induced AD mouse model by reinvigorating the T cell immune balance, shedding light on the future development and application of novel HB-based therapeutics for AD.

New Treatments for Atopic Dermatitis Targeting Skin Barrier Repair via the Regulation of FLG Expression

Atopic dermatitis (AD) is one of the most common chronic, inflammatory skin disorders with a complex etiology and a broad spectrum of clinical phenotypes. Despite its high prevalence and effect on the quality of life, safe and effective systemic therapies approved for long-term management of AD are limited. A better understanding of the pathogenesis of atopic dermatitis in recent years has contributed to the development of new therapeutic approaches that target specific pathophysiological pathways. Skin barrier dysfunction and immunological abnormalities are critical in the pathogenesis of AD. Recently, the importance of the downregulation of epidermal differentiation complex (EDC) molecules caused by external and internal stimuli has been extensively emphasized. The purpose of this review is to discuss the innovations in the therapy of atopic dermatitis, including biologics, small molecule therapies, and other drugs by highlighting regulatory mechanisms of skin barrier-related molecules, such as filaggrin (FLG) as a crucial pathway implicated in AD pathogenesis.

Therapeutic New Era for Atopic Dermatitis: Part 2. Small Molecules

Atopic dermatitis (AD) is a chronic, inflammatory cutaneous disease driven by immune dysregulation and skin barrier dysfunction. Currently, we are experiencing a new era of understanding of the pathogenesis of AD and, as a consequence, a new era of innovation in therapeutics, including small molecules and biologic therapy. In contrast to biologics, small molecules are similar to conventional pharmacologic chemical agents used as drugs and are generally prepared by chemical synthesis. Unlike biologics, these drugs often are taken orally or formulated for topical use. The purpose of this review is to summarize the efficacy and safety of the current topical and systemic new therapies in AD by reviewing recently published papers on therapies currently in phase 2 or 3 clinical trials. In this review, it is important to note the characteristics of the study population, the primary endpoints, and whether or not there was concomitant topical therapy allowed. These study design elements may significantly alter the results of studies and should be taken into account. Targeted therapy help push AD treatment into a new era of personalized medicine.

Current and emerging biologics for the treatment of pediatric atopic dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a chronic inflammatory skin condition characterized by erythematous lesions, pruritus, and a skin barrier defect. Long-term treatment in children is challenging, as there is only one Food and Drug Administration-approved systemic medication. Current treatments may have limited efficacy or serious side effects in children. With a deeper understanding of AD pathogenesis and the advent of target-specific medications, several biologics are undergoing clinical trials for future use in pediatric AD.

AREAS COVERED

This article reviews the current and emerging biologic therapies for treatment of pediatric AD. It allows for comprehensive comparison of medications and their clinical trials to help providers optimize patient treatment plans while providing expert insight into upcoming advancements in the treatment of pediatric AD.

EXPERT OPINION

Treating pediatric AD is complicated given the variety of disease severity, psychosocial impact, and relative lack of approved medications for severe disease. Given the safety data on dupilumab, newer biologics will likely be second-line. We do not yet understand the long-term impact of newer biologics on an immature immune system, nor do we fully understand their risks and toxicities. We should proceed optimistically, yet cautiously, with the study of biologics in children.

Omalizumab for treatment of refractory severe atopic dermatitis. A pediatric perspective

Omalizumab is a monoclonal antibody, targeting Fc receptor of IgE, approved for the treatment of allergic asthma and chronic spontaneous urticaria. Its utility in atopic dermatitis appears controversial from data in literature since the molecule is well tolerated but it seems less effective than other medications used in adult patients (eg, Dupilumab). At present, the use of Dupilumab is not approved in pediatric patients therefore there are no second level treatments available in this age group. Here we report two clinical cases of patients (15 and 16 years old) suffering from both atopic dermatitis and asthma, treated with Omalizumab. Our experience suggests that atopic eczema of young patients with allergic comorbidities can benefit from asthma treatment with Omalizumab observing improvement on both conditions.

Scoping Review on the Use of Drugs Targeting JAK/STAT Pathway in Atopic Dermatitis, Vitiligo, and Alopecia Areata

INTRODUCTION

The JAK/STAT signaling pathway is involved in the immune-mediated inflammatory skin diseases atopic dermatitis (AD), vitiligo, and alopecia areata (AA), and represents a potential target when developing treatments. So far, no drugs targeting this pathway have been approved for the treatment of dermatological diseases. We reviewed the use of drugs blocking the JAK/STAT pathway in the aforementioned diseases.

METHODS

An a priori protocol was published. We used Joanna Briggs Institute Reviewer's Manual methodology to conduct the review and PRISMA Extension for Scoping Review (PRISMA-ScR) to report results. MEDLINE, EMBASE, CINAHL, Scopus, and Web of Science databases were searched in a three-step approach on April 2019 by two researchers.

RESULTS

Ninety-six mainly multicenter observational studies were included (66, 10, and 20 studies on AA, vitiligo, and AD, respectively). Tofacitinib and ruxolitinib were mainly used for the three diseases, and also upadacitinib, abrocitinib, baricitinib, cerdulatinib, delgocitinib, gusacitinib for AD, and baricitinib, PF-06700841, and PF-06651600 for AA. All patients with AD improved, whereas patients with vitiligo and patients with AA showed varied responses, including unresponsive cases. The safety profiles were similar for all drugs and diseases, mainly comprising mild or no adverse events.

CONCLUSIONS

Evidence on the efficacy and safety of drugs targeting the JAK/STAT pathway for the treatment of patients with AD, vitiligo, or AA is increasing but is still of low quality.

Topical and Oral Therapies for Childhood Atopic Dermatitis and Plaque Psoriasis

BACKGROUND

Treatment of atopic dermatitis and psoriasis in children is difficult due to lack of standardized treatment guidelines and few FDA-approved treatment options. Treatments approved for adults may be used off-label in pediatric patients.

OBJECTIVE

This review evaluates the topical and oral treatment options available, including off-label uses, and provides a basic therapeutic guideline for pediatric atopic dermatitis and psoriasis.

METHODS

A PubMed review of topical and systemic treatments for pediatric psoriasis and atopic dermatitis with information regarding age, efficacy, dosing, contra-indications, adverse events, and off-label treatments.

RESULTS

The search identified seven topical and five systemic treatments that are routinely employed to treat pediatric atopic dermatitis and psoriasis.

LIMITATIONS

Standardized guidelines regarding treatment choice, dosing, and long-term safety are scarce. Reviews may be subject to ascertainment bias.

CONCLUSIONS

Current treatment guidelines are based on clinical experience and expert advice with few treatments officially approved for atopic dermatitis and psoriasis in children.