Novel Targeted Biological Agents for the Treatment of Atopic Dermatitis

Functional magnetic resonance imaging in prurigo nodularis: A call to study neural sensitization phenomena

Prurigo nodularis is a chronic pruritic, inflammatory skin condition characterized by nodular skin lesions in a typical distribution pattern caused by various dermatologic and/or nondermatologic conditions. In recent years, significant advances have been made in the understanding of the cutaneous pathophysiology of prurigo nodularis, resulting in novel treatment options such as interleukin-4, -13, -17, and -31 or Janus kinase inhibitors. Many aspects of the neurophysiology are largely unknown, including the processing in the central structural and functional network involved in prurigo nodularis. Functional neuroimaging allows noninvasive assessment of brain function and structure. Due to its high spatial resolution and temporal precision, functional magnetic resonance imaging has proven to be a suitable method for exploring neural mechanisms and assessing pharmacologic effects in dermatologic research. In this systematic review, the current knowledge of functional magnetic resonance imaging in the context of prurigo nodularis and its centrally active treatment options is summarized.

The AhR-Ovol1-Id1 regulatory axis in keratinocytes promotes epidermal and immune homeostasis in atopic dermatitis-like skin inflammation

The skin is our outer permeability and immune defense barrier against myriad external assaults. Aryl hydrocarbon receptor (AhR) senses environmental factors and regulates barrier robustness and immune homeostasis. AhR agonists have been approved by the FDA for psoriasis treatment and are in clinical trials for the treatment of atopic dermatitis (AD), but the underlying mechanism of action remains poorly defined. Here, we report that OVOL1/Ovol1 is a conserved and direct transcriptional target of AhR in epidermal keratinocytes. We show that OVOL1/Ovol1 influences AhR-mediated regulation of keratinocyte gene expression and that OVOL1/Ovol1 ablation in keratinocytes impairs the barrier-promoting function of AhR, exacerbating AD-like inflammation. Mechanistically, we have identified Ovol1's direct downstream targets genome-wide and provided in vivo evidence supporting the role of Id1 as a functional target in barrier maintenance, disease suppression, and neutrophil accumulation. Furthermore, our findings reveal that an IL-1/dermal γδT cell axis exacerbates type 2 and 3 immune responses downstream of barrier perturbation in Ovol1-deficient AD skin. Finally, we present data suggesting the clinical relevance of OVOL1 and ID1 functions in human AD skin. Our study highlights a keratinocyte-intrinsic AhR-Ovol1-Id1 regulatory axis that promotes both epidermal and immune homeostasis in the context of skin inflammation, identifying new therapeutic targets.

Comparative efficacy and safety of dupilumab versus newly approved biologics and JAKi in pediatric atopic dermatitis: A systematic review and network meta-analysis

BACKGROUND

The newly approved biologics and Janus kinase inhibitors (JAKi) for pediatric atopic dermatitis (AD) offer additional options for clinical treatment. However, the efficacy and safety differences compared to the first approved biologic, dupilumab, remain unclear. Therefore, a network meta-analysis was conducted to evaluate these differences and identify potentially superior agents.

METHODS

This systematic review was PROSPERO-registered (CRD42024583658). Randomized controlled trials involving pediatric patients (<18 years old) published in PubMed, Embase, Web of Science, and the Cochrane Library up to October 27, 2024 were searched and screened. RevMan software was utilized for quality assessment, and  meta-analysis was performed using R version 4.4.1. Efficacy measures included the Investigator's Global Assessment (IGA), the Numeric Rating Scale for Itch (NRS), and the Eczema Area and Severity Index (EASI). The results of these measures were expressed as odds ratios (OR), while treatment rankings of different interventions were determined using the P-score.

RESULT

This study included 11 trials involving 7 agents and 2,352 pediatric patients. The results indicated that dupilumab (300 mg) showed better outcomes than placebo in IGA-0/1 (OR =  4.68, 95% CI: 2.53-8.63), NRS-4 (OR =  6.75, 95% CI: 3.85-11.86), and all EASI outcomes. Tralokinumab may be the most effective option for alleviating pruritus (P-score for NRS-4, 0.8447). Upadacitinib (30 mg) performed best in IGA-0/1 (P-score, 0.9414), EASI-90 (P-score, 0.9926), and EASI-75 (P-score, 0.9707). Dupilumab (300 mg) had a higher risk of nasopharyngitis compared to placebo (OR = 2.15, 95%CI: 1.04-4.43). Compared to both placebo and dupilumab (300 mg), adverse event rates were higher with upadacitinib (15 mg and 30 mg), and upper respiratory tract infection risk was elevated with baricitinib (2 mg and 4 mg) and tralokinumab (300 mg).

CONCLUSION

The efficacy of dupilumab for pediatric AD remains substantial, while other agents including upadacitinib, delgocitinib, and tralokinumab also present certain advantages. Future clinical trials may necessitate further evaluation of safety concerns.

Microneedles as transdermal drug delivery system for enhancing skin disease treatment

Microneedles (MNs) serve as a revolutionary paradigm in transdermal drug delivery, heralding a viable resolution to the formidable barriers presented by the cutaneous interface. This review examines MNs as an advanced approach to enhancing dermatological pathology management. It explores the complex dermis structure and highlights the limitations of traditional transdermal methods, emphasizing MNs' advantage in bypassing the stratum corneum to deliver drugs directly to the subdermal matrix. The discourse outlines the diverse typologies of MNs, including solid, coated, hollow, hydrogel, and dissolvable versions. Each type is characterized by its unique applications and benefits. The treatise details the deployment of MNs in the alleviation of cutaneous cancers, the administration of inflammatory dermatoses such as psoriasis and atopic dermatitis, and their utility in wound management. Additionally, the paper contemplates the prospects of MNs within the realm of aesthetic dermatology and the burgeoning market traction of cosmetic MN formulations. The review summarizes the scientific and commercial challenges to the clinical adoption of MN therapeutics, including dosage calibration, pharmacodynamics, biocompatibility, patient compliance, sterilization, mass production, and regulatory oversight. It emphasizes the need for ongoing research, innovation, and regulatory harmonization to overcome these obstacles and fully realize MNs' potential in treating skin diseases and improving patient welfare.

Assessing Disease Control in Patients with Atopic Dermatitis by Using the Atopic Dermatitis Control Tool in Daily Practice

INTRODUCTION

Atopic dermatitis (AD) is a chronic inflammatory skin disease, placing a significant burden on patients' quality of life (QoL). The validated Atopic Dermatitis Control Tool (ADCT) is recommended to assess AD control in adults. The aim of this study was to assess AD control and explore associations with demographic characteristics, patient-reported outcome measures (PROMs), and treatment.

METHODS

In this cross-sectional study, questionnaires were sent to 2,066 adults from two tertiary referral centers who had previously physician-diagnosed AD and had visited the outpatient clinic at least once between 2020 and 2022. Questionnaires were completed between May and October 2022. AD control was assessed by the ADCT, with a score ≥7 indicating uncontrolled AD. AD severity, QoL, and weekly average pruritus were simultaneously measured using the Patient-Oriented Eczema Measure (POEM), Dermatology Life Quality Index (DLQI), and numeric rating scale (NRS), respectively, with higher scores indicating more severe symptoms. Moreover, treatment-related questions were included. Associations between uncontrolled AD, age, sex, and treatment were explored using multivariate logistic regression analysis.

RESULTS

In total, 863 patients (41.8%) filled out the questionnaire and 812 were included in the analysis, of which 59% reported controlled AD. Uncontrolled AD was associated with higher PROM scores and receiving topical anti-inflammatories only (adjusted odds ratio [95% confidence interval] ranged from 1.33 [0.995-1.88] to 2.55 [2.21-2.86]). Of those treated with topical anti-inflammatories only, 54% reported uncontrolled AD.

CONCLUSION

The majority of the patients reported controlled AD. Patients with uncontrolled AD often reported more severe symptoms and were more likely to receive topical anti-inflammatories only. It could be considered to shift patients with uncontrolled AD from topical to systemic treatment.

Biologic and small-molecule therapy for treating moderate to severe atopic dermatitis: Mechanistic considerations

Atopic dermatitis (AD) is a complex and heterogeneous skin disease for which achieving complete clinical clearance for most patients has proven challenging through single cytokine inhibition. Current studies integrate biomarkers and evaluate their role in AD, aiming to advance our understanding of the diverse molecular profiles implicated. Although traditionally characterized as a TH2-driven disease, extensive research has recently revealed the involvement of TH1, TH17, and TH22 immune pathways as well as the interplay of pivotal immune molecules, such as OX40, OX40 ligand (OX40L), thymic stromal lymphopoietin, and IL-33. This review explores the mechanistic effects of treatments for AD, focusing on mAbs and Janus kinase inhibitors. It describes how these treatments modulate immune pathways and examines their impact on key inflammatory and barrier biomarkers.

The beneficial effects of ethanolic extract of Sargassum serratifolium in DNCB-induced mouse model of atopic dermatitis

Atopic dermatitis is a chronic complex inflammatory skin disorder that requires sustainable treatment methods due to the limited efficacy of conventional therapies. Sargassum serratifolium, an algal species with diverse bioactive substances, is investigated in this study for its potential benefits as a therapeutic agent for atopic dermatitis. RNA sequencing of LPS-stimulated macrophages treated with ethanolic extract of Sargassum serratifolium (ESS) revealed its ability to inhibit a broad range of inflammation-related signaling, which was proven in RAW 264.7 and HaCaT cells. In DNCB-induced BALB/c or HR-1 mice, ESS treatment improved symptoms of atopic dermatitis within the skin, along with histological improvements such as reduced epidermal thickness and infiltration of mast cells. ESS showed a tendency to improve serum IgE levels and inflammation-related cytokine changes, while also improving the mRNA expression levels of Chi3l3, Ccr1, and Fcεr1a genes in the skin. Additionally, ESS compounds (sargachromanol (SCM), sargaquinoic acid (SQA), and sargahydroquinoic acid (SHQA)) mitigated inflammatory responses in LPS-treated RAW264.7 macrophages. In summary, ESS has an anti-inflammatory effect and improves atopic dermatitis, ESS may be applied as a therapeutics for atopic dermatitis.

Lebrikizumab: First Approval

Lebrikizumab (Ebglyss®) is a subcutaneous recombinant humanized IgG4 anti-IL-13 monoclonal antibody developed by Almirall S.A. and Eli Lilly and Company for the treatment of atopic dermatitis (AD). In November 2023, lebrikizumab was approved in the EU for the treatment of moderate-to-severe AD in adults and adolescents 12 years and older with a body weight of at least 40 kg who are candidates for systemic therapy. Lebrikizumab was approved for the same indication in the UK in December 2023 and in Japan in January 2024. Lebrikizumab is under regulatory review for the treatment of AD in the USA, Switzerland and Australia. This article summarizes the milestones in the development of lebrikizumab leading to this first approval for AD.

An AhR-Ovol1-Id1 regulatory axis in keratinocytes promotes skin homeostasis against atopic dermatitis

Skin is our outer permeability and immune defense barrier against myriad external assaults. Aryl hydrocarbon receptor (AhR) senses environmental factors and regulates barrier robustness and immune homeostasis. AhR agonist is in clinical trial for atopic dermatitis (AD) treatment, but the underlying mechanism of action remains ill-defined. Here we report OVOL1/Ovol1 as a conserved and direct transcriptional target of AhR in epidermal keratinocytes. We show that OVOL1/Ovol1 impacts AhR regulation of keratinocyte gene expression, and Ovol1 deletion in keratinocytes hampers AhR's barrier promotion function and worsens AD-like inflammation. Mechanistically, we identify Ovol1's direct downstream targets genome-wide, and provide in vivo evidence for Id1's critical role in barrier maintenance and disease suppression. Furthermore, our findings reveal an IL-1/dermal γδT cell axis exacerbating both type 2 and type 3 immune responses downstream of barrier perturbation in Ovol1 -deficient AD skin. Finally, we present data suggesting the clinical relevance of OVOL1 and ID1 function in human AD. Our study highlights a keratinocyte-intrinsic AhR-Ovol1-Id1 regulatory axis that promotes both epidermal and immune homeostasis against AD-like inflammation, implicating new therapeutic targets for AD.

Short-term efficacy and safety of biologics and Janus kinase inhibitors for patients with atopic dermatitis: A systematic review and meta-analysis

Background

In recent years, biologics targeting key cytokines and Janus kinase (JAK) inhibitors have demonstrated favorable efficacy and safety outcomes for atopic dermatitis (AD) therapy. To evaluate the short-term efficacy and safety of AD therapy involving biologics, JAK inhibitors, and their combination with topical corticosteroids (TCS) for patients with AD, we conducted this systematic review and meta-analysis. Using eligible randomized clinical trials (RCTs) of 12 or 16 weeks of treatment with systemic medications and 4 weeks of topical treatment for AD.

Methods

PubMed, Web of Science, ScienceDirect, and the Cochrane Library were searched from inception up to October 25, 2023. English-language randomized clinical trials (RCTs) of 12 or 16 weeks of treatment with systemic medications and 4 weeks of topical treatment for AD were included. Titles, abstracts, and articles were screened in duplicate. Of 7261 citations, 37 studies were included. The data were analyzed using Review Manager 5.4 and the outcomes were measured by the Eczema Area and Severity Index (EASI), Investigator Global Assessment (IGA), the pruritus Numerical Rating Scale (NRS), as well as instances of adverse events (AE), and serious AE (SAE), which were presented as risk ratio (RR) with a 95 % confidence interval (CI). The efficacy of the biological therapies was analyzed with the percentage of patients who have achieved EASI 75, EASI 90, IGA 0/1 and pruritus NRS4, while the safety of treatments was evaluated in terms of the number of patients who had ≥1 AE and who had at least one SAE.

Results

A total of 37 studies with 43 cohorts that examined 9 medications and placebo and involved 18172 participants were included. Compared with the placebo, all biologics and JAK inhibitors were associated with a higher response rate in efficacy outcomes, while systematic administration was presented by dupilumab 200 mg subcutaneously every 2 weeks with superior improvement in EASI 90 (RR 9.50, 95 % CI 2.31-39.03) and IGA0/1 (RR 17.00, 95 % CI 2.33-123.78), upadacitinib 30 mg once daily in EASI 75 (RR 5.14, 95 % CI 4.20-6.31) and Pruritus NRS4 (RR 5.73, 95 % CI 4.44-7.39), and external use was presented by ruxolitinib 1.5 % twice daily orally in EASI 75 (RR 4.14, 95 % CI 3.06-5.61) and Pruritus NRS4 (RR 4.08, 95 % CI 2.86-5.81), and most of doses led to a better safety profile. Most doses of baricitinib, dupilumab, tralokinumab, and upadacitinib in combination with TCS demonstrated good efficacy as compared with the control groups (placebo + TCS). However, patients receiving baricitinib at a dosage of 2 mg daily (RR 1.23, 95 % CI 1.02-1.49) and 4 mg daily (RR 1.39, 95 % CI 1.22-1.58) in combination with TCS, exhibited a higher incidence of one or more SAE as compared with those taking placebo + TCS.

Conclusion

Our research has revealed that ruxolitinib and dupilumab are effective and safe treatments for mild to moderate AD and moderate to severe AD, respectively. Additionally, the combination of dupilumab and TCS demonstrates greater efficacy and safety compared to baricitinib, tralokinumab, and upadacitinib with TCS as a background treatment for moderate to severe AD. We suggest that the use of topical JAK inhibitors could be a potential alternative to TCS when used in combination with systemic medications, as a novel approach to treat AD. Insufficient different data sources caused by partial interventions were only mentioned in a few articles and low event rates in safety analyses may lead to the results being biased. Further studies directly comparing existing and novel treatments are needed and will be included in forthcoming updates of this review. Our findings could form a useful foundation for developing a new generation of treatment guidelines for AD.

"Input/output cytokines" in epidermal keratinocytes and the involvement in inflammatory skin diseases

Considering the role of epidermal keratinocytes, they occupy more than 90% of the epidermis, form a physical barrier, and also function as innate immune barrier. For example, epidermal keratinocytes are capable of recognizing various cytokines and pathogen-associated molecular pattern, and producing a wide variety of inflammatory cytokines, chemokines, and antimicrobial peptides. Previous basic studies have shown that the immune response of epidermal keratinocytes has a significant impact on inflammatory skin diseases. The purpose of this review is to provide foundation of knowledge on the cytokines which are recognized or produced by epidermal keratinocytes. Since a number of biologics for skin diseases have appeared, it is necessary to fully understand the relationship between epidermal keratinocytes and the cytokines. In this review, the cytokines recognized by epidermal keratinocytes are specifically introduced as "input cytokines", and the produced cytokines as "output cytokines". Furthermore, we also refer to the existence of biologics against those input and output cytokines, and the target skin diseases. These use results demonstrate how important targeted cytokines are in real skin diseases, and enhance our understanding of the cytokines.

Disease modification in inflammatory skin disorders: opportunities and challenges

Progress in understanding of the mechanisms underlying chronic inflammatory skin disorders, such as atopic dermatitis and psoriasis vulgaris, has led to new treatment options with the primary goal of alleviating symptoms. In addition, this knowledge has the potential to inform on new strategies aimed at inducing deep and therapy-free remission, that is, disease modification, potentially impacting on associated comorbidities. However, to reach this goal, key areas require further exploration, including the definitions of disease modification and disease activity index, further understanding of disease mechanisms and systemic spillover effects, potential windows of opportunity, biomarkers for patient stratification and successful intervention, as well as appropriate study design. This Perspective article assesses the opportunities and challenges in the discovery and development of disease-modifying therapies for chronic inflammatory skin disorders.

Repressive Control of Keratinocyte Cytoplasmic Inflammatory Signaling

The overactivity of keratinocyte cytoplasmic signaling contributes to several cutaneous inflammatory and immune pathologies. An important emerging complement to proteins responsible for this overactivity is signal repression brought about by several proteins and protein complexes with the native role of limiting inflammation. The signaling repression by these proteins distinguishes them from transmembrane receptors, kinases, and inflammasomes, which drive inflammation. For these proteins, defects or deficiencies, whether naturally arising or in experimentally engineered skin inflammation models, have clearly linked them to maintaining keratinocytes in a non-activated state or returning cells to a post-inflamed state after a signaling event. Thus, together, these proteins help to resolve acute inflammatory responses or limit the development of chronic cutaneous inflammatory disease. We present here an integrated set of demonstrated or potentially inflammation-repressive proteins or protein complexes (linear ubiquitin chain assembly complex [LUBAC], cylindromatosis lysine 63 deubiquitinase [CYLD], tumor necrosis factor alpha-induced protein 3-interacting protein 1 [TNIP1], A20, and OTULIN) for a comprehensive view of cytoplasmic signaling highlighting protein players repressing inflammation as the needed counterpoints to signal activators and amplifiers. Ebb and flow of players on both sides of this inflammation equation would be of physiological advantage to allow acute response to damage or pathogens and yet guard against chronic inflammatory disease. Further investigation of the players responsible for repressing cytoplasmic signaling would be foundational to developing new chemical-entity pharmacologics to stabilize or enhance their function when clinical intervention is needed to restore balance.

Anti-Atopic Effect of Isatidis Folium Water Extract in TNF-α/IFN-γ-Induced HaCaT Cells and DNCB-Induced Atopic Dermatitis Mouse Model

Isatidis folium or Isatis tinctoria L. is a flowering plant of the Brassicaceae family, commonly known as woad, with an ancient and well-documented history as an indigo dye and medicinal plant. This study aimed to evaluate the anti-atopic dermatitis (AD) effects of Isatidis folium water extract (WIF) using a 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model and to investigate the underlying mechanism using tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)-activated HaCaT cells. Oral administration of WIF reduced spleen weight, decreased serum IgE and TNF-α levels, reduced epidermal and dermal thickness, and inhibited eosinophil and mast cell recruitment to the dermis compared to DNCB-induced control groups. Furthermore, oral WIF administration suppressed extracellular signal-regulated kinase and p38 mitogen-activated protein kinase protein expression levels, p65 translocation from the cytoplasm to the nucleus, and mRNA expression of TNF-α, IFN-γ, interleukin (IL)-6, and IL-13 in skin lesion tissues. In HaCaT cells, WIF suppressed the production of regulated upon activation, normal T cell expressed and secreted (RANTES), thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), MCP-1, and MIP-3a, which are inflammatory cytokines and chemokines related to AD, and inhibited the mRNA expression of RANTES, TARC, and MDC in TNF-α/IFN-γ-stimulated HaCaT cells. Overall, the results revealed that WIF ameliorated AD-like skin inflammation by suppressing proinflammatory cytokine and chemokine production via nuclear factor-κB pathway inhibition, suggesting WIF as a potential candidate for AD treatment.

Novel Therapeutic Targets for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease that significantly impacts quality of life. The pathogenesis of AD is a complex combination of skin barrier dysfunction, type II immune response, and pruritus. Progress in the understanding of the immunological mechanisms of AD has led to the recognition of multiple novel therapeutic targets. For systemic therapy, new biologic agents that target IL-13, IL-22, IL-33, the IL-23/IL-17 axis, and OX40-OX40L are being developed. Binding of type II cytokines to their receptors activates Janus kinase (JAK) and its downstream signal, namely signal transduction and activator of transcription (STAT). JAK inhibitors block the activation of the JAK-STAT pathway, thereby blocking the signaling pathways mediated by type II cytokines. In addition to oral JAK inhibitors, histamine H4 receptor antagonists are under investigation as small-molecule compounds. For topical therapy, JAK inhibitors, aryl hydrocarbon receptor modulators, and phosphodiesterase-4 inhibitors are being approved. Microbiome modulation is also being examined for the treatment of AD. This review outlines current and future directions for novel therapies of AD that are currently being investigated in clinical trials, focusing on their mechanisms of action and efficacy. This supports the accumulation of data on advanced treatments for AD in the new era of precision medicine.

How to Understand Personalized Medicine in Atopic Dermatitis Nowadays?

Atopic dermatitis (AD) is a heterogeneous disease in terms of its phenotypical, barrier, and immunological presentation. Emerging therapies are undoubtedly contributing to a new chapter in the treatment of AD, bringing an excellent possibility of individualization, and thereby creating a tailored approach. The two most promising substance groups are biological drugs (dupilumab, tralokinumab, lebrikizumab, nemolizumab) and Janus kinase inhibitors (JAKis) (baricitinib, upadacitinib, and abrocitinib). The vision that certain well-defined phenotypes and endotypes, as well as personal preferences, may guide the future treatment of AD is both tempting and appealing, but not yet reality. The accessibility of new drugs such as biologics and small molecules has opened up the discussion regarding personalized medicine, referring to the complex nature of AD as well as the experiences from clinical trials and real-world evidence. We have now reached the point of creating new strategies and AD treatment goals by increasing the amount of new information concerning the efficacy and safety of new drugs. This article has reviewed the novel treatment options for AD in the light of the heterogeneity of this disease and proposes a broader vision on the strategy of personalized treatment of AD.

Biologics for pediatric atopic dermatitis: A protocol of a systematic review and meta-analysis

BACKGROUND

Atopic dermatitis is a chronic pruritic inflammatory skin disease commonly occurring in children. The objective of this study is to evaluate the treatment of pediatric atopic dermatitis with biologics, as they have displayed immense promising results in several recent clinical trials on atopic dermatitis (AD).

METHODS

We will conduct an extensive search for RCTs in several databases, including Embase, Cochrane Library, Web of Science, and PubMed, from the inception of the study till 15th May 2022. The primary outcomes will be the proportion of patients with EASI 75/90/100 after 12-16 weeks of treatment. The secondary outcomes will include the Numerical Rating Scale (NRS), Investigator Global Assessment (IGA)0-1, body surface area (BSA), Dermatology Life Quality Index (DLQI) scores, and incidence of adverse reactions. All studies will be screened by two independent researchers. They will assess the risk of bias in the included studies according to the RCTs bias risk evaluation tool in Cochrane System Review Manual 5.1.0. Meta-analysis will be performed using RevMan V.5.3.0 software.

RESULTS

The research results will provide a reference for the clinical application of biological agents in pediatric atopic dermatitis.

CONCLUSION

We aim to evaluate the efficacy and safety of biologics in pediatric atopic dermatitis cases and provide evidence-based data for easy clinical application.

PROSPERO REGISTRATION NUMBER

CRD42022319052 (https://www.crd.york.ac.uk/PROSPERO/#joinuppage).

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.

Current and Emerging Therapies in Pediatric Atopic Dermatitis

Atopic dermatitis (AD) is the most common inflammatory skin disease seen in children. It is a heterogeneous disorder, with a variety of associated manifestations and symptoms. Cases may range from mild to severe. As a result, a spectrum of prescription and nonprescription therapies may be utilized when managing this condition. This article provides an extensive overview of these therapies, with equal consideration provided to current, emerging, and alternative options used in the pediatric population.

Clinical efficacy and safety of topical difamilast in the treatment of patients with atopic dermatitis: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To investigate the clinical efficacy and safety of topical difamilast in mild-to-moderate atopic dermatitis (AD).

METHODS

Only randomized controlled trials (RCTs) that compared topical difamilast with vehicle treatment for patients with AD were included. PubMed, Web of Science, Ovid Medline, Cochrane Library, ClinicalTrials.gov and JapicCTI were searched to 10 April 2022.

RESULTS

Five studies enrolling a total of 1009 patients with mild-to-moderate AD were identified. Compared with the topical vehicle, topical difamilast was associated with a significantly higher success rate according to the Investigator's Global Assessment score at week 4 (relative risk, 2.82; 95% confidence interval [CI]: 2.11-3.77). Compared with the vehicle, difamilast was associated with a significant decrease in day 28 eczema area and severity index scores (mean difference [MD], -4.10; 95% CI: -5.32 to -2.87), verbal rating scale scores (MD, -0.51; 95% CI: -0.71 to -0.32), visual analog scale scores (MD, -12.15; 95% CI: -19.70 to -4.61), patient-oriented eczema measure values (MD, -3.99; 95% CI: -4.91 to -3.07), and total affected body surface area (MD, -6.48; 95% CI: -8.09 to -4.87). No difference in treatment-related adverse events was identified.

CONCLUSIONS

This meta-analysis suggests that topical difamilast is an effective and safe treatment for mild-to-moderate AD.

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.

Opioidergic Signaling-A Neglected, Yet Potentially Important Player in Atopic Dermatitis

Atopic dermatitis (AD) is one of the most common skin diseases, the prevalence of which is especially high among children. Although our understanding about its pathogenesis has substantially grown in recent years, and hence, several novel therapeutic targets have been successfully exploited in the management of the disease, we still lack curative treatments for it. Thus, there is an unmet societal demand to identify further details of its pathogenesis to thereby pave the way for novel therapeutic approaches with favorable side effect profiles. It is commonly accepted that dysfunction of the complex cutaneous barrier plays a central role in the development of AD; therefore, the signaling pathways involved in the regulation of this quite complex process are likely to be involved in the pathogenesis of the disease and can provide novel, promising, yet unexplored therapeutic targets. Thus, in the current review, we aim to summarize the available potentially AD-relevant data regarding one such signaling pathway, namely cutaneous opioidergic signaling.

Portuguese recommendations for the treatment of atopic dermatitis with biologic therapy and JAK inhibitors in adult patients

Atopic dermatitis is a highly prevalent chronic, immune-mediated inflammatory skin disease with a significant burden on patients, families and healthcare systems. This article presents recommendations developed by the Atopic Dermatitis Group of the Portuguese Society of Dermatology and Venereology addressing several clinical questions that arise in the management and care of moderate-to-severe atopic dermatitis with biologic agents and Janus kinase (JAK) inhibitors based on the available evidence. The recommendations were generated after a thorough evaluation of existing guidelines on the treatment of atopic dermatitis, publications concerning new biologics and JAK inhibitors not yet incorporated into existing guidelines, and expert-based recommendations. It also includes considerations on atopic dermatitis severity, indications for initiating biologic agents and JAK inhibitors, parameters to be considered in the treatment choice, in particular treatment goals, and recommendations for the use, screening and monitoring of these therapies.

Low-dose intralesional injection of 5-fluorouracil and triamcinolone reduces tissue resident memory T cells in chronic eczema

BACKGROUND

Tissue resident memory T (T_RM) cells have been reported to play a significant role in the pathogenesis and relapse of chronic eczema.

AIM

To compare the efficacy and safety of the intralesional injection of 5-fluorouracil (5-FU) and triamcinolone (TA) with those associated with TA alone for the treatment of chronic eczema.

METHODS

A total of 168 patients were randomized to 5-FU+TA or TA groups and received a one-time intralesional injection of 5-FU+TA or TA only. Biopsies were collected before and 2 wk after treatment for evaluation of histopathological changes. All patients were followed up monthly for up to 1 year.

RESULTS

No serious adverse event was observed in either group. Although the mean atopic dermatitis severity index scores and effective rates were comparable between the two groups after 2 wk of treatment, the relapse rate was significantly lower in the 5-FU+TA group than in the TA group. Histological examination showed significantly fewer CD8⁺ and CD103⁺ T cells but not CD4⁺ T cells in the 5-FU+TA group.

CONCLUSION

One-time intralesional injection of 5-FU+TA is effective and safe for chronic eczema treatment and can further reduce the retention of T_RM cells in the lesional skin and the relapse rate of chronic eczema.

Safety and Danger Considerations of Novel Treatments for Atopic Dermatitis in Context of Primary Cutaneous Lymphomas

The impact of new and emerging therapies on the microenvironment of primary cutaneous lymphomas (PCLs) has been recently raised in the literature. Concomitantly, novel treatments are already used or registered (dupilumab, upadacitinib) and others seem to be added to the armamentarium against atopic dermatitis. Our aim was to review the literature on interleukins 4, 13, 22, and 31, and JAK/STAT pathways in PCLs to elucidate the safety of using biologics (dupilumab, tralokinumab, fezakinumab, nemolizumab) and small molecule inhibitors (upadacitinib, baricitinib, abrocitinib, ruxolitinib, tofacitinib) in the treatment of atopic dermatitis. We summarized the current state of knowledge on this topic based on the search of the PubMed database and related references published before 21 October 2021. Our analysis suggests that some of the mentioned agents (dupilumab, ruxolitinib) and others may have a direct impact on the progression of cutaneous lymphomas. This issue requires further study and meticulous monitoring of patients receiving these drugs to ensure their safety, especially in light of the FDA warning on tofacitinib. In conclusion, in the case of the rapid progression of atopic dermatitis/eczema, especially in patients older than 40 years old, there is a necessity to perform a biopsy followed by a very careful pathological examination.

The Role of Cord Blood in the Regulation of the Cellular and Humoral Link of Immunity in Experimental Atopic Dermatitis

Background. Atopic dermatitis (AD) as one of the most common diseases of autoimmune genesis in the structure of dermatological practice, is characterized by itching, dryness, thickening of the skin, characteristic rashes. The drugs of choice in the treatment of AD are steroidal anti-inflammatory drugs. However, the development of unwanted side effects is a serious problem attributed to using hormone therapy. The search for effective methods of treating AD is an urgent task of medicine and in particular dermatology. At the same time, there is an obvious need for the participation in the solution of this problem also of specialists-immunologists working in the field of application of cell therapy drugs, acting on various pathogenetic links of the disease. The development of new or optimization of existing methods of treating AD is the urgent task facing them. Objective. Evaluation of the immunocorrective effect of lyophilized (lHCBL) and cryopreserved human cord blood leucoconcetrate (cHCBL) on a AD model. Methods. The experiments were carried out on 6-month-old Wistar rats. Upon induction of AD, the inflammation focus was formed on the rat's back (9–10 cm2) by daily rubbing in a 5% alcohol-acetone solution of dinitrochlorobenzene (DNCB) for 21 days. cHCBL and lHCBL were injected intraperitoneally, 0.5 ml at a dose of 5´106 cells in one day after the final DNCB treatment. The adhesive and phagocytic activity of the cells of the peritoneal cavity, the level of circulating immune complexes, the population and subpopulation of lymphocytes (CD3+, CD4+, CD8+, CD16+, CD4+CD25+), the immunoregulatory index of lymphocytes, the concentration of immunoglobulins in the blood serum were determined. Results. For AD induced by DNCB, systemic changes in the immune status are characteristic, which is expressed by changes in the parameters of cellular and humoral immunity. The most fundamental changes in cell subpopulations in spleen of rats with AD were revealed: a decrease in the number of total T-lymphocytes and their two main subpopulations (CD4+ and CD8+ cells). Against this background, changes were noted in the monocytic-phagocytic and humoral systems of immunity. The paper shows the effectiveness of the use of cHCBL and lHCBL in the correction of pathological manifestations of experimental AD. On the background of treatment, the features of the immunocorrective effect of each of the drugs were noted. Thus, when assessing intergroup values, a more pronounced increase in T-reg was revealed in rats of the 5th group – 3.9 [3.8; 4.0] versus 3.2 [3.0; 3.3] in the 4th group (P < 0.01); IgA level – 1.6 [1.5; 1.7] versus 1.3 [1.2; 1.4] (P < 0.01). Conclusions. Thus, lHCBL exhibits immunocorrective activity in the treatment of experimental AD, surpassing in some parameters the activity of сHCBL, which is promising for its use in clinical practice.