Review and analysis of biologic therapies currently in phase II and phase III clinical trials for atopic dermatitis

Treatment of atopic dermatitis: Recently approved drugs and advanced clinical development programs

Atopic dermatitis (AD) represents the most common skin disease characterized by heterogeneous endophenotypes and a high disease burden. In Europe, six new systemic therapies for AD have been approved: the biologics dupilumab (anti-interleukin-4 receptor (IL-4R) α in 2017), tralokinumab (anti-IL-13 in 2021), lebrikizumab (anti-IL-13 in 2023), and the oral janus kinase (JAK) inhibitors (JAKi) targeting JAK1/2 (baricitinib in 2020 in the EU) or JAK1 (upadacitinib in 2021 and abrocitinib in 2022). Herein, we give an update on new approvals, long-term safety, and efficacy. Upadacitinib and abrocitinib have the highest short-term efficacy among the approved systemic therapies. In responders, dupilumab and tralokinumab catch up regarding long-term efficacy and incremental clinical benefit within continuous use. Recently, the European Medicines Agency has released recommendations for the use of JAKi in patients at risk (cardiovascular and thromboembolic diseases, malignancies, (former) smoking, and age ≥65 years). Furthermore, we give an overview on emerging therapies currently in Phase III trials. Among the topical therapies, tapinarof (aryl hydrocarbon receptor), ruxolitinib (JAK1/2i), delgocitinib (pan-JAKi), asivatrep (anti-transient receptor potential vanilloid), and phosphodiesterase-4-inhibitors (roflumilast, difamilast) are discussed. Among systemic therapies, current data on cord-blood-derived mesenchymal stem cells, CM310 (anti IL-4Rα), nemolizumab (anti-IL-31RA), anti-OX40/OX40L-antibodies, neurokinin-receptor-1-antagonists, and difelikefalin (κ-opioid-R) are reported.

The Future of Food Allergy Management: Advancements in Therapies

PURPOSE OF REVIEW

To review current and future treatment options for IgE-mediated food allergy.

RECENT FINDINGS

Recent years have seen major developments in both allergen-specific and allergen-non-specific treatment options, with the first FDA-approved peanut oral immunotherapy (OIT) product becoming available in 2020. In addition to OIT, other immunotherapy modalities, biologics, adjunct therapies, and novel therapeutics are under investigation. Food allergy is a potentially life-threatening condition associated with a significant psychosocial impact. Numerous products and protocols are under investigation, with most studies focusing on OIT. A high rate of adverse events, need for frequent office visits, and cost remain challenges with OIT. Further work is needed to unify outcome measures, develop treatment protocols that minimize adverse events, establish demographic and clinical factors that influence candidate selection, and identify patient priorities.

IL-22 as a target for therapeutic intervention: Current knowledge on its role in various diseases

IL-22 has emerged as a crucial cytokine mediating protective response against pathogens and tissue regeneration. Dysregulated production of IL-22 has been shown to play a pivotal role in the pathogenesis of various diseases like malignant tumours, viral, cardiovascular, allergic and autoimmune disorders. Interleukin 22 belongs to IFN-IL-10 cytokine family. It is a major proinflammatory cytokine secreted by activated Th1 cells (Th22), though can also be secreted by many other immune cells like group 3 innate lymphocytes, γδ T cells, NK cells, NK T cells, and mucosal associated invariant T cells. Th22 cells exclusively release IL-22 but not IL-17 or IFN-γ (as Th1 cells releases IFN-γ along with IL-22 and Th17 cells releases IL-17 along with IL-22) and also express aryl hydrocarbon receptor as the key transcription factor. Th22 cells also exhibit expression of chemokine receptor CCR6 and skin-homing receptors CCR4 and CCR10 indicating the involvement of this subset in bolstering epithelial barrier immunity and promoting secretion of antimicrobial peptides (AMPs) from intestinal epithelial cells. The function of IL-22 is modulated by IL-22 binding protein (binds to IL-22 and inhibits it binding to its cell surface receptor); which serves as a competitor for IL-22R1 chain of IL-22 receptor. The pathogenic and protective nature of the Th22 cells is modulated both by the site of infected tissue and the type of disease pathology. This review aims to discuss key features of IL-22 biology, comparisons between IL and 22 and IFN-γ and its role as a potential immune therapy target in different maladies.

Anti-inflammatory and biologic drugs for atopic dermatitis: a therapeutic approach in children and adolescents

Atopic dermatitis (AD) is a chronic inflammatory disease with a heterogeneous pathogenesis correlated with dysregulation of the immune system and a prevalence of the T2-mediated immune pathway. Recent understanding of the pathogenesis of AD has allowed the development of new drugs targeting different mechanisms and cytokines that have changed the treatment approach. The aim of this review is to update knowledge on the standard of care and recent advancements in the control of skin inflammation. In light of recent guidelines, we report on the clinical efficacy of novel treatments, with special attention to situations where biologics and small molecules are involved.

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.

Biologicals in IgE-mediated food allergy

PURPOSE OF REVIEW

A better understanding of the most recent scientific literature in the use of biological therapy in the treatment of patients with IgE-mediated food allergy.

RECENT FINDINGS

A systematic review and meta-analysis demonstrated safety and effectiveness of omalizumab in the treatment of food allergy. The findings support the potential use of omalizumab as a monotherapy or as an adjunct to oral immunotherapy in IgE-mediated cow's milk allergy. The potential use of other biologics in the management of food allergy is subject of speculation.

SUMMARY

Different biological therapies are under evaluation for food allergic patients. The advance in literature will guide for a personalized treatment in the near future. However, additional research is needed to better understand the best candidate for each treatment, the optimal dose and timing.

Biological agents targeting interleukin-13 for atopic dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a chronic inflammatory skin disease that is pathogenically driven by type-2 inflammation. Interleukin-13 (IL-13) plays a central role in AD pathogenesis, as confirmed by the clinical efficacy of agents that selectively block IL-13, although their therapeutic value and place-in-therapy are incompletely defined.

AREAS COVERED

The aim of this review article is to describe preclinical and clinical data regarding selective IL-13 inhibitors investigated in AD. In particular, we discuss the clinical outcomes obtained with lebrikizumab and tralokinumab, which are in a more advanced phase of development.

EXPERT OPINION

Biological agents that neutralize IL-13 have demonstrated clinical benefits in treating AD with excellent safety profiles. Robust clinical evidence exists in support of tralokinumab, which underwent phase III trials, met the predefined primary endpoints, and is approaching the market. In contrast, clinical trial testing for lebrikizumab needs to be completed to fully assess its therapeutic potential.

PLAIN LANGUAGE SUMMARY

Atopic dermatitis (AD) is a chronic pathological inflammatory skin disease that results from type-2 inflammation. Selective interleukin-13 (IL-13) inhibitors have shown clinical efficacy against AD, suggesting that IL-13 plays a central in AD pathogenesis. However, the therapeutic value and place-in-therapy of IL-13 inhibitors are incompletely defined. The aim of this review article is to describe preclinical and clinical data for selective IL-13 inhibitors against AD, including lebrikizumab and tralokinumab, which are in a more advanced phase of development. The up-to-date overview of the strengths and limitations of different agents used to treat AD discussed in this article might be useful in driving treatment decision.

Patterns of Atopic Eczema Disease Activity From Birth Through Midlife in 2 British Birth Cohorts

Importance

Atopic eczema is characterized by a heterogenous waxing and waning course, with variable age of onset and persistence of symptoms. Distinct patterns of disease activity such as early-onset/resolving and persistent disease have been identified throughout childhood; little is known about patterns into adulthood.

Objective

This study aimed to identify subtypes of atopic eczema based on patterns of disease activity through mid-adulthood, to examine whether early life risk factors and participant characteristics are associated with these subtypes, and to determine whether subtypes are associated with other atopic diseases and general health in mid-adulthood.

Design, Setting, and Participants

This study evaluated members of 2 population-based birth cohorts, the 1958 National Childhood Development Study (NCDS) and the 1970 British Cohort Study (BCS70). Participant data were collected over the period between 1958 and 2016. Data were analyzed over the period between 2018 and 2020.

Main Outcomes and Measures

Subtypes of atopic eczema were identified based on self-reported atopic eczema period prevalence at multiple occasions. These subtypes were the outcome in models of early life characteristics and an exposure variable in models of midlife health.

Results

Latent class analysis identified 4 subtypes of atopic eczema with distinct patterns of disease activity among 15 939 individuals from the NCDS (51.4% male, 75.4% White) and 14 966 individuals from the BCS70 (51.6% male, 78.8% White): rare/no (88% to 91%), decreasing (4%), increasing (2% to 6%), and persistently high (2% to 3%) probability of reporting prevalent atopic eczema with age. Sex at birth and early life factors, including social class, region of residence, tobacco smoke exposure, and breastfeeding, predicted differences between the 3 atopic eczema subtypes and the infrequent/no atopic eczema group, but only female sex differentiated the high and decreasing probability subtypes (odds ratio [OR], 1.99; 95% CI, 1.66-2.38). Individuals in the high subtype were most likely to experience asthma and rhinitis, and those in the increasing subtype were at higher risk of poor self-reported general (OR, 1.29; 95% CI, 1.09-1.53) and mental (OR 1.45; 95% CI, 1.23-1.72) health in midlife.

Conclusions and Relevance

The findings of this cohort study suggest that extending the window of observation beyond childhood may reveal clear subtypes of atopic eczema based on patterns of disease activity. A newly identified subtype with increasing probability of activity in adulthood warrants additional attention given observed associations with poor self-reported health in midlife.

Role of Th22 Cells in the Pathogenesis of Autoimmune Diseases

Upon antigenic stimulation, naïve CD4+T cells differentiate into different subsets and secrete various cytokines to exert biological effects. Th22 cells, a newly identified CD4+T cell subset,are distinct from the Th1, Th2 and Th17 subsets. Th22 cells secrete certain cytokines such as IL-22, IL-13 and TNF-α, but not others, such as IL-17, IL-4, or interferon-γ (IFN-γ), and they express chemokine receptors CCR4, CCR6 and CCR10. Th22 cells were initially found to play a role in skin inflammatory diseases, but recent studies have demonstrated their involvement in the development of various autoimmune diseases. Here, we review research advances in the origin, characteristics and effector mechanisms of Th22 cells, with an emphasis on the role of Th22 cells and their main effector cytokine IL-22 in the pathogenesis of autoimmune diseases. The findings presented here may facilitate the development of new therapeutic strategies for targeting these diseases.

Th2 Modulation of Transient Receptor Potential Channels: An Unmet Therapeutic Intervention for Atopic Dermatitis

Atopic dermatitis (AD) is a multifaceted, chronic relapsing inflammatory skin disease that affects people of all ages. It is characterized by chronic eczema, constant pruritus, and severe discomfort. AD often progresses from mild annoyance to intractable pruritic inflammatory lesions associated with exacerbated skin sensitivity. The T helper-2 (Th2) response is mainly linked to the acute and subacute phase, whereas Th1 response has been associated in addition with the chronic phase. IL-17, IL-22, TSLP, and IL-31 also play a role in AD. Transient receptor potential (TRP) cation channels play a significant role in neuroinflammation, itch and pain, indicating neuroimmune circuits in AD. However, the Th2-driven cutaneous sensitization of TRP channels is underappreciated. Emerging findings suggest that critical Th2-related cytokines cause potentiation of TRP channels, thereby exaggerating inflammation and itch sensation. Evidence involves the following: (i) IL-13 enhances TRPV1 and TRPA1 transcription levels; (ii) IL-31 sensitizes TRPV1 via transcriptional and channel modulation, and indirectly modulates TRPV3 in keratinocytes; (iii) The Th2-cytokine TSLP increases TRPA1 synthesis in sensory neurons. These changes could be further enhanced by other Th2 cytokines, including IL-4, IL-25, and IL-33, which are inducers for IL-13, IL-31, or TSLP in skin. Taken together, this review highlights that Th2 cytokines potentiate TRP channels through diverse mechanisms under different inflammatory and pruritic conditions, and link this effect to distinct signaling cascades in AD. This review strengthens the notion that interrupting Th2-driven modulation of TRP channels will inhibit transition from acute to chronic AD, thereby aiding the development of effective therapeutics and treatment optimization.

Innate Immune Regulation of Dermatitis

Dermatitis encompasses a spectrum of inflammatory skin disorders with aberrant immune responses classified as type 1, type 2, and/or type 3. Major advances in the understanding of the pathogenesis of atopic dermatitis (AD) have shed new light on how innate immune responses critically regulate type 2 inflammation and itch. This article highlights the diverse ways by which type 2 immune cells regulate diseases beyond AD. The discovery of human Mas-related G protein-coupled receptor X2 on mast cells has revealed novel T cell-independent and immunoglobulin E-independent mechanisms of allergic contact dermatitis-associated and urticarial itch, respectively.

The use of biologics in food allergy

BACKGROUND

Food allergy continues to pose problems due to its increased frequency and its increasingly high severity. In this context, alongside the traditional avoidance strategies of allergenic foods and desensitization through the cautious progression of exposure to foods in the context of oral immunotherapy (OIT), alternative strategies have made their way in the last decades. We review the possibilities of intervention in food allergy with the use of biological drugs capable of interfering with the synthesis of IgE, with their mechanisms of action, or with complex biological mechanisms that lead to the establishment of a food allergy.

METHODS

Repeated Entrez PubMed searches using the template algorithm "Food allergy" and "biologics" or "Omalizumab" or "Dupilumab" or "milk desensitization" or "oral tolerance induction" or "oral immunotherapy" or "Etokimab" or "Tezepelumab" or "Quilizumab" or "Ligelizumab" or "Tralokinumab" or "Nemolizumab" or "Mepolizumab" or "Reslizumab" or "Benralizumab". The authors' clinical experience in paediatric allergy units of University hospitals was also drawn upon.

RESULTS

The landscape in this context has changed dramatically over the past 10 years. We have acquired knowledge mainly on the effect of different types of anti-IgE treatments in poliallergic patients with food allergy, and in patients treated with OIT. However, other mediators are being targeted by specific biologic treatments. Among them, the alarmins Il-33 and TSLP, IL-4 and IL-13, eosinophil-related molecules as IL-6, IL-8, IL-10, IL-12, and mostly IL-5, and integrins involved in the pathogenesis of eosinophilic gastrointestinal diseases (EGIDs), as SIGLEC-8.

CONCLUSIONS

The ever-better knowledge of the mechanisms of food allergy allowing these developments will improve not only the perspective of patients with the most serious immediate food allergies such as anaphylaxis, but also those of patients with related diseases such as atopic dermatitis, eosinophilic esophagitis, and EGIDs. Biologics are also intended to complement OIT strategies that have developed over the years.

Molecular Mechanisms of Atopic Dermatitis Pathogenesis

Atopic dermatitis is a chronic, non-infectious inflammatory dermatosis. Acharacteristic feature is persistent itching of the skin. The chronic, relapsing course of the disease, economic burden, and the whole family’s involvement in the treatment process immensely reduce the quality of life of patients and their families. The disease emerges as a social problem by increasing indirect costs, such as visiting a doctor, absenteeism from work and school, and avoiding social interactions. Thepathophysiology of atopic dermatitis is complex and multifactorial. It includes genetic disorders, a defect in the epidermal barrier, an altered immune response, anddisruption of the skin’s microbial balance. The numerous complex changes at thegenetic level and innate and adaptive immunity provide the basis for characterizing the various phenotypes and endotypes of atopic dermatitis. Emerging therapies rely on the action of specific molecules involved in the disease’s pathogenesis. It may be the starting point for the individualization of atopic dermatitis treatment. This paper will try to present some molecular mechanisms of atopic dermatitis and their clinical implications.

Therapeutic targeting of the IL-13 pathway in skin inflammation

Introduction: Atopic dermatitis (AD) is a heterogeneous, chronic, inflammatory skin disease with a non-negligible prevalence at present. Its pathogenesis is complex, but mainly characterized by constitutive T helper type 2 (Th2)-cell activation. Systemic therapies for moderate-to-severe AD can be associated with adverse events that encumber their satisfactory long-term use. Several drugs targeting relevant molecules in the immunopathogenesis of AD have been approved or are under clinical development for the treatment of moderate to severe AD. To elaborate this review, literature searches were performed in PubMed on 29 August 2020.Areas covered: This narrative literature review is focused on the pivotal role of IL-13 in the immunopathogenesis of AD and other skin diseases.Expert opinion: Dupilumab has demonstrated the central role of IL-13 and IL-4 in the pathogenesis of AD, asthma, and other diseases in the atopic spectrum. In addition, phase III randomized clinical trials (RCTs) evaluating specific blockade of IL-13 with tralokinumab for treatment of AD also demonstrated favorable results, and phase III RCT evaluating lebrikizumab are ongoing. The role of IL-13 in other skin diseases should be further investigated.