New treatments for chronic urticaria

Sexual Dysfunction in Chronic Urticaria: A Systematic Review

INTRODUCTION

Chronic urticaria (CU) is frequently a debilitating skin condition characterized by recurrent and spontaneous wheal and flares with significant impact on quality of life. This systematic review examines the impact of CU on sexual health.

METHODS

A systematic review using PubMed, Embase, Web of Science, and Cochrane library databases was conducted for articles on sexual health in chronic urticaria.

RESULTS

The database search produced 741 articles, of which 14 articles met inclusion criteria. Study design, patient demographics, disease characteristics, measures used to assess sexuality or sexual function, and study results were independently extracted for each article by two researchers. Any discrepancies were resolved to consensus by a third reviewer. Sexual dysfunction was common in patients with CU and its severity is associated with increased disease activity and poor disease control.

CONCLUSION

Sexual dysfunction is common in patients with CU, and it negatively affects their quality of life (QoL), body image, sleep quality, and mental health. Incorporating sexual health assessments into CU trials will allow for valuable insights into efficacy of study medications on this important QoL domain. Increased awareness of sexual impairment in CU is needed to provide comprehensive care.

Biomarkers for Short-Term Omalizumab Response in Chronic Spontaneous Urticaria

BACKGROUND

Omalizumab, a monoclonal antibody targeting immunoglobulin E (IgE), is approved for adults and adolescents (12 years or older) with chronic spontaneous urticaria (CSU) that does not respond to high-dose antihistamines. In Korea, there is limited research on predictive biomarkers for omalizumab response in CSU patients.

OBJECTIVE

This retrospective, single-institution study aimed to identify clinical parameters predicting omalizumab response in Korean CSU patients.

METHODS

We analyzed records of CSU patients aged 19 or older starting omalizumab between January 2017 and October 2019. Omalizumab efficacy was assessed using the Urticaria Activity Score summed over 7 days (UAS7), categorized as well-controlled, mild, moderate, or severe. Ninety CSU patients participated in this study.

RESULTS

Among these, improvements in UAS7 categories from baseline to 12 weeks of treatment were observed in 78 patients, while 12 patients showed no significant efficacy. The present study identified potential biomarkers that could predict a patient's response to omalizumab, including disease duration and total serum IgE levels (p=0.022, p=0.046). Notably, a significant correlation was observed between higher detection rates in multiple antigen simultaneous test (MAST) food testing and lower treatment responses (p=0.033).

CONCLUSION

Shorter disease duration of CSU and elevated initial serum total IgE level may serve as potential predictive biomarkers for the responsiveness to omalizumab. Furthermore, a higher MAST food detection rate seemed to correlate with a less favorable treatment response, suggesting patients with a high MAST food detection rate might benefit from a food evaluation in addition to omalizumab treatment.

Bridging the gap through telemedicine: Pilot study on the acceptance and use of teledermatology for urticaria

BACKGROUND

Chronic spontaneous urticaria (CSU) significantly impairs patients' quality of life. Despite advances in diagnosis and therapy, treatment is still unsatisfactory. Telemedicine offers a promising solution to improve treatment. This pilot study assesses the acceptability and utilization of a digital health model for CSU, examines its impact on disease management, and identifies technical challenges.

PATIENTS AND METHODS

In this prospective pilot study, CSU patients at a university hospital in Germany were included. Over 12 months, participants interacted with physicians via a telemedicine platform, which was the study-specific intervention. After each three-month digital visit, symptoms and quality of life were assessed using electronic patient reported outcomes (ePROs) and online questionnaires. In the end, patients and doctors rated the overall satisfaction, the user-friendliness of the platform and the technical challenges.

RESULTS

24 patients completed the study. The majority (92%) reported that the digital concept could be a promising alternative to traditional consultations. Analysis from baseline to end of study revealed that disease control remained stable while quality of life improved. All physicians found the digital application reliable and time-saving.

CONCLUSIONS

This pilot study demonstrates the feasibility and high acceptance of a digital health model for the management of CSU. Further research with larger cohorts is needed and planned to determine broader applicability.

Dupilumab Reduces Urticaria Activity, Itch, and Hives in Patients with Chronic Spontaneous Urticaria Regardless of Baseline Serum Immunoglobulin E Levels

INTRODUCTION

In chronic spontaneous urticaria (CSU), interleukin (IL)-4 and IL-13 may promote mast cell activation directly via IL-4 receptor expression, or indirectly via upregulated immunoglobulin E (IgE) production. Dupilumab significantly improved CSU signs and symptoms in the phase 3, randomized, placebo-controlled LIBERTY-CSU CUPID Study A. This analysis explores the impact of dupilumab on CSU signs and symptoms and serum IgE levels in patients from LIBERTY-CSU CUPID Study A with serum total IgE above and below 100 IU/mL at baseline.

METHODS

Patients with H1-antihistamine-refractory CSU received dupilumab (n = 70) or placebo (n = 68) for 24 weeks. Efficacy endpoints were change from baseline to weeks 12 and 24 in serum total IgE levels, Itch Severity Score over 7 days (ISS7), Urticaria Activity Score over 7 days (UAS7), and Hives Severity Score over 7 days (HSS7) in dupilumab- or placebo-treated patients with serum total IgE above and below 100 IU/mL at baseline.

RESULTS

Dupilumab treatment significantly reduced median (interquartile range) IgE levels at week 12 [dupilumab: -31.9% (-41.9; -22.6); placebo: -6.3% (-21.3; 14.9)] and week 24 [dupilumab: -48.2% (-56.8; - 39.5); placebo: - 6.3% (-34.5; 14.8)]. Similar IgE reductions relative to baseline were observed in dupilumab-treated patients regardless of baseline IgE level. Dupilumab treatment improved ISS7, UAS7, and HSS7 over 12 and 24 weeks, regardless of baseline serum IgE level (interaction p ≥ 0.59 for all treatment by subgroup comparisons), with weak correlations (r < 0.2) observed between IgE level changes and ISS7, UAS7, and HSS7 outcomes.

CONCLUSIONS

Dupilumab significantly improved CSU signs and symptoms and reduced serum IgE, regardless of baseline IgE levels. In the current analysis, baseline total IgE had no predictive value as a dupilumab treatment response biomarker in CSU. Downregulation of IgE, a key mediator of mast cell activation and histamine release, may at least partially explain the effectiveness of dupilumab in reducing CSU signs and symptoms.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04180488.

A comprehensive analysis on the safety of two biologics dupilumab and omalizumab

Dupilumab was approved for the treatment of several dermatologic immune-mediated inflammatory diseases, such as atopic dermatitis and bullous pemphigoid; whereas omalizumab is the first biological agent which was approved to treat chronic spontaneous urticaria. None of the published meta-analyses has provided the sufficient data regarding the safety of these two biologics, especially regarding their potential serious adverse events (SAEs). The aim of this study was, to comprehensively evaluate the safety of the two biologics dupilumab and omalizumab. In this study, we included 32 randomized trials, and performed meta-analyses on 113 types of SAEs regarding dupilumab and 61 types of SAEs regarding omalizumab. We identified that: (1) use of dupilumab was significantly associated with the lower incidence of atopic dermatitis, while use of omalizumab was significantly associated with the lower incidence of asthma; and (2) use of dupilumab was not significantly associated with the incidences of 112 other kinds of SAEs including various infectious diseases, while use of omalizumab was not significantly associated with the incidences of 60 other kinds of SAEs including various infectious diseases. This meta-analysis for the first time assessed the association between use of dupilumab or omalizumab and incidences of various SAEs, and identified that neither dupilumab use nor omalizumab use was associated with the increased risks of any SAEs including various infectious diseases. These findings further confirm the general safety of the two biologics dupilumab and omalizumab. This informs clinicians that there is no need to worry too much about the safety issues of these two biologics.

Chronic Inducible Urticaria

Chronic inducible urticaria (CIndU) is characterized by the appearance of hives (urticaria) and/or angioedema in response to specific triggers or stimuli. For accurate diagnosis, anamnesis-driven specific, and if available, standardized trigger testings, as well as patient reported outcomes, should be applied. The currently recommended treatment algorithm is the same as for chronic spontaneous urticaria but is largely off-label for CIndU. New, and possibly more disease-specific, treatment options are needed for CIndU patients, who are often severely impacted by their disease. Several clinical trials are currently ongoing.

Update on Urticaria and Angioedema

Urticaria and angioedema are caused by immunoglobulin E- and non-immunoglobulin E-mediated release of histamine and other inflammatory mediators from mast cells and basophils. Diagnosis is made clinically, and anaphylaxis must be ruled out if urticaria or angioedema is present. A limited nonspecific laboratory workup should be considered unless elements of the history or physical examination suggest specific underlying conditions. The mainstay of treatment is avoidance of triggers when and if triggers are identified. The first-line pharmacotherapy is second-generation H1 antihistamines, which can be titrated to greater than standard doses.

What can be learned from real-world data about chronic spontaneous urticaria?

Background: Chronic spontaneous urticaria (CSU) is a common disease with complex pathogenesis. Patients' clinical characteristics and responses to treatment vary. Objective: We aimed to investigate the role of data obtained from routinely recommended tests in predicting the response to omalizumab, the only biologic agent approved for treatment, and in defining the clinical characteristics of the patients. Methods: A retrospective study of patients who started omalizumab treatment for CSU between 2015 and 2022 at the Department of Dermatology, Pamukkale University, was conducted. Response criteria were based on the urticaria control test, and patients with a urticaria control test score <12 at 6 months were considered treatment non-responders. Eosinophil and basophil counts, neutrophil-lymphocyte ratio (NLR), systemic immune inflammation index (SII), systemic inflammation response index (SIRI), and total immunoglobulin E (IgE) levels of the patients were evaluated before treatment and at the sixth month of treatment. Results: A total of 23.1% of the patients were unresponsive to omalizumab. The response rate to the omalizumab treatment of the patients with a total IgE level ≤ 30 IU/L (n = 4 [5.7%]) was significantly lower than patients with total IgE level > 30 IU/L (n = 66 [94.3%]) (p = 0.015). The mean ± standard deviation SIRI levels were significantly higher in non-responders versus responders (1.53 ± 1.03 versus 1.15 ± 7.76; p = 0.026). Eosinophil counts positively correlated with basophil counts (r = 587; p < 0.001) and IgE levels (r = 0.290; p = 0.005) but a negative correlation was found with levels of NLR (r = -0.475; p < 0.001), SIRI (r = -0.259; p = 0.013), and SII (r = -0.285; p = 0.006). NLR levels were lower in CSU patients with atopy, than in those without atopy (1.9 ± 0.9 vs 2.9 ± 2.1, p = 0.022). Conclusion: We suggest that eosinopenia and high NLR levels are linked to autoimmune CSU. Predicting a poor response to omalizumab seems possible with total IgE levels < 30 IU/L and high SIRI levels.

Clinical values of serum neuropeptide changes in patients with chronic urticaria complicated with allergic rhinitis

AIM

Neurogenic inflammation has been recognized as an important contributing factor in the pathogenesis of allergic rhinitis. The aim of this study was to investigate the clinical values of substance P, vasoactive intestinal peptide (VIP), and neuropeptide Y as biomarkers of disease severity and treatment outcomes of chronic urticaria complicated with allergic rhinitis.

METHODS

Our prospective study included 150 patients with chronic urticaria complicated with allergic rhinitis and 80 healthy control patients. Before treatment, the serum samples of all study subjects were collected and analyzed using enzyme-linked immunosorbent analysis. The intervention group received imipramine of 10 mg/day orally for 2 weeks, and the Symptom Score Reduction Index (SSRI) was used to analyze clinical outcomes, which were categorized as effectual and ineffectual.

RESULTS

Our data suggested that substance P, VIP, and neuropeptide Y were significantly correlated to each other. Lower levels of substance P, VIP, and neuropeptide Y were associated with better treatment outcomes. A good detection sensitivity (69.49%) and specificity (80.22%) could be achieved using a combination of these markers (area under curve = 0.85).

CONCLUSIONS

Our data indicates that substance P, VIP, and neuropeptide Y levels before treatment correlate strongly with the treatment outcomes of the patients, which could potentially serve as a decision support tool in clinical management of chronic urticaria complicated with allergic rhinitis.

A Practical Guide to Using Biologics in Pediatric Dermatology

Psoriasis, hidradenitis suppurativa (HS), atopic dermatitis (AD), and chronic spontaneous urticaria (CSU), are common, immune-mediated, chronic, inflammatory skin diseases that can affect the pediatric population. While there is adequate evidence supporting the use of biologics in pediatric patients, concerns regarding safety and efficacy amongst healthcare providers are not uncommon. However, new emerging evidence in this population highlights the safety of biologic therapy, making it crucial to review and establish a practical guide for their use. This article describes a methodological framework for initiating biologics in the management of pediatric psoriasis, HS, AD, and CSU, with a special focus on baseline work-up, monitoring, dosing, and considerations in this population.

Mast cell silencing: A novel therapeutic approach for urticaria and other mast cell-mediated diseases

Chronic urticaria (CU) is a mast cell (MC)-dependent disease with limited therapeutic options. Current management strategies are directed at inhibiting IgE-mediated activation of MCs and antagonizing effects of released mediators. Due to the complexity and heterogeneity of CU and other MC diseases and mechanisms of MC activation-including multiple activating receptors and ligands, diverse signaling pathways, and a menagerie of mediators-strategies of MC depletion or MC silencing (i.e., inhibition of MC activation via binding of inhibitory receptors) have been developed to overcome limitations of singularly targeted agents. MC silencers, such as agonist monoclonal antibodies that engage inhibitory receptors (e.g., sialic acid-binding immunoglobulin-like lectin8 -[Siglec-8] [lirentelimab/AK002], Siglec-6 [AK006], and CD200R [LY3454738]), have reached preclinical and clinical stages of development. In this review, we (1) describe the role of MCs in the pathogenesis of CU, highlighting similarities with other MC diseases in disease mechanisms and response to treatment; (2) explore current therapeutic strategies, categorized by nonspecific immunosuppression, targeted inhibition of MC activation or mediators, and targeted modulation of MC activity; and (3) introduce the concept of MC silencing as an emerging strategy that could selectively block activation of MCs without eliciting or exacerbating on- or off-target, immunosuppressive adverse effects.

The 7-day recall period version of the Urticaria Control Test-UCT7

BACKGROUND

The Urticaria Control Test (UCT) is a well-established, very easy to use and calculate 4-item patient-reported outcome measure to assess chronic urticaria disease control during the previous 4 weeks. Clinical trials and practice may benefit from the use of a UCT version with a shorter recall period, but this does not exist.

OBJECTIVES

We sought to develop and validate a UCT version with a 7-day recall period, the UCT7.

METHODS

The UCT7 was developed, based on the UCT, and tested, in 152 patients with chronic urticaria (spontaneous: n = 101, inducible: n = 51) for its reliability, validity and screening accuracy, and clinimetric properties, in other words, the cutoff for well-controlled disease and the minimal clinically important difference.

RESULTS

The UCT7 showed excellent internal consistency reliability with a Cronbach αvalue of 0.91 and test-retest reliability with an intraclass correlation coefficient of 0.83. Convergent validity was high and strongly correlated with anchors of disease control, wheal and angioedema frequency, and urticaria-related quality of life impairment. The UCT7 showed excellent sensitivity to change; however, changes in angioedema activity and impact did not correlate well with changes in UCT7. Based on receiver-operating characteristic curve analysis, the proportion of correctly classified patients, and patients' assessment of treatment efficacy, we recommend a cutoff value of 12 points for identifying patients with well-controlled disease. The UCT7 minimal clinically important difference for improvement was estimated to be 2 points.

CONCLUSIONS

The UCT7 is a validated 7-day recall period version of the UCT. It is ideal for the assessment of disease control at short intervals in patients with chronic urticaria in clinical studies and practice.

The evolving landscape of immunotherapy for the treatment of allergic conditions

Allergic conditions, such as asthma, chronic urticaria, atopic dermatitis (AD), and eosinophilic esophagitis, have long been treated with oral and topical steroids which resulted in negative off-target effects. However, newer biologic medications are increasingly being developed and approved for treatment of these conditions. These medications have a variety of mechanisms of action to target pathophysiology specific to these diseases. As biologics become more targeted, fewer off-target effects are seen improving tolerability for patients as well as expanded options for treatment of these conditions. This review discusses monoclonal antibody therapies (omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab, tezepelumab, and tralokinumab) including their safety and use in asthma, chronic urticaria, AD, and eosinophilic esophagitis.

Association Between Serum Total IgE Levels and Clinical Response to Omalizumab for Chronic Spontaneous Urticaria: A Systematic Review and Meta-Analysis

BACKGROUND

Omalizumab is the only biological agent approved for patients with chronic spontaneous urticaria (CSU), but no biomarker is well established for predicting clinical response to omalizumab.

OBJECTIVE

We aimed to determine the association between baseline total serum IgE levels and the effects of omalizumab in patients with CSU.

METHODS

PubMed, Web of Science, Scopus, and Cochrane Library were systematically searched for relevant studies from inception to August 23, 2022. The research protocol was registered on PROSPERO (CRD42022355592). No language restrictions were applied. A random-effects model was used for meta-analysis.

RESULTS

Ten interventional studies, including 1 randomized controlled trial, were included in the final meta-analysis, and a total of 866 patients with CSU were included. A pooled analysis showed significantly higher serum total IgE levels in complete responders (CRs) than in nonresponders (NRs) (mean difference [MD]: 56.509 IU/mL; 95% confidence interval [CI]: 24.230-88.789) and in partial responders (PRs) than in NRs (MD: 62.688 IU/mL; 95% CI: 32.949-92.427), but no significant difference was detected between CRs and PRs. The mean total IgE levels for CRs, PRs, and NRs were 163.154, 179.926, and 51.535 IU/mL, respectively. Further, the serum total IgE levels in early CRs were significantly higher compared with late CRs (MD: 55.194 IU/mL; 95% CI: 13.402-96.986). The sensitivity analyses with the leave-one-out method validated the robustness of all findings.

CONCLUSIONS

This systematic review and meta-analysis provide convincing evidence that pretreatment total serum IgE levels in patients with CSU are associated with clinical responses to omalizumab.

The correlation between Th17/Treg immune dysregulation and the disease severity in chronic spontaneous urticaria patients

OBJECTIVE

Chronic spontaneous urticaria (CSU) has a profound impact on the sleep quality, productivity and overall quality of life of affected individuals. This study aimed to investigate the correlation between serum Th17/Treg immune dysregulation and the severity of CSU in patients.

METHODS

Clinical baseline data of 120 CSU patients and matched healthy controls were recorded. The pruritus level, disease severity, and quality of life of CSU patients were assessed using the visual analogue scale, weekly Urticaria Activity Score and chronic urticaria quality of life questionnaire, respectively. The Th17/Treg cell ratio was detected by flow cytometry. ELISA was used to measure the levels of serum Th17 cytokines (IL-17, IL-21) and Treg cytokines (TGF-β1, IL-35). Pearson's correlation analysis was conducted to examine the associations between these indicators.

RESULTS

No significant differences were identified in terms of sex, age, and BMI between the two groups. However, CSU patients exhibited a significant increase in the Th17 cell ratio, as well as the elevated serum levels of TGF-β1, IL-17 and, IL-21. Conversely, the proportion of Treg cells and the levels of IL-35 were remarkably decreased in CSU patients. Peripheral blood Th17 cells were negatively correlated with Treg cells. The severity of pruritus, life quality, and disease severity in CSU patients were positively correlated to Th17 cell ratio, and inversely correlated with Treg cell proportion.

CONCLUSIONS

A positive correlation was found between the percentage of peripheral blood Th17 cell in CSU patients and the pruritus level, life quality, and disease severity. In constrast, there was a negative correlation between the proportion of peripheral blood Treg cells and these clinical parameters.

Current and Emerging Therapies for Chronic Spontaneous Urticaria: A Narrative Review

Chronic spontaneous urticaria (CSU) is a condition in which wheals, angioedema, and pruritus occur spontaneously and recurrently for at least 6 weeks. The etiology of this disease is partially dependent on production of autoantibodies that activate and recruit inflammatory cells. Although the wheals can resolve within 24 h, symptoms have a significant detrimental impact on the quality of life of these patients. Standard therapy for CSU includes second-generation antihistamines and omalizumab. However, many patients tend to be refractory to these therapies. Available treatments such as cyclosporine, dapsone, dupilumab, and tumor necrosis factor alpha (TNFa) inhibitors have been used with success in some cases. Furthermore, various biologics and other novel drugs have emerged as potential treatments for this condition, and many more are currently under investigation in randomized clinical trials.

Chronic Spontaneous Urticaria: How to Measure It and the Need to Define Treatment Success

Chronic spontaneous urticaria (CSU) is a complex skin disease characterized by the spontaneous appearance of wheals, angioedema, or both, for more than 6 weeks. Many patients experience a relapsing-remitting disease course for years. Owing to the unpredictability of wheal recurrence and the severity of pruritis, patients suffer considerable impairment in their quality of life. Physicians face multiple challenges, not least of which is a lack of clear guidance on what constitutes "treatment success". There is a lack of awareness of which measures should be used to best assess the various aspects of CSU, including disease activity, disease control, and quality of life-which themselves each comprise multiple components-and how to apply the results of each score to treatment decision-making. Although the overarching aim of treatment is for patients to be completely free of signs and symptoms of CSU, a more realistic definition of "treatment success" is needed to guide ongoing, long-term disease management for each individual patient. In this review, we consider what lessons can be learned from the current evidence base to provide further direction toward a universal definition of "treatment success".

Mast Cells in Upper and Lower Airway Diseases: Sentinels in the Front Line

Mast cells (MCs) are fascinating cells of the innate immune system involved not only in allergic reaction but also in tissue homeostasis, response to infection, wound healing, protection against kidney injury, the effects of pollution and, in some circumstances, cancer. Indeed, exploring their role in respiratory allergic diseases would give us, perhaps, novel therapy targets. Based on this, there is currently a great demand for therapeutic regimens to enfeeble the damaging impact of MCs in these pathological conditions. Several strategies can accomplish this at different levels in response to MC activation, including targeting individual mediators released by MCs, blockade of receptors for MC-released compounds, inhibition of MC activation, limiting mast cell growth, or inducing mast cell apoptosis. The current work focuses on and summarizes the mast cells' role in pathogenesis and as a personalized treatment target in allergic rhinitis and asthma; even these supposed treatments are still at the preclinical stage.

Management of eosinophil-associated inflammatory diseases: the importance of a multidisciplinary approach

Elevated eosinophil counts in blood and tissue are a feature of many pathological processes. Eosinophils can migrate and accumulate in a wide variety of tissues and, by infiltrating a target organ, can mediate the development of several inflammatory diseases. The normalization of eosinophilia is a common biomarker of a treatable trait and can also be used as a prognostic and predictive biomarker since it implies a reduction in type 2 inflammation that contributes to disease pathogenesis. Biological therapies targeting this cell type and its proinflammatory mediators have been shown to be effective in the management of a number of eosinophilic diseases, and for this reason they constitute a potential common strategy in the treatment of patients with various multimorbidities that present with type 2 inflammation. Various biological options are available that could be used to simultaneously treat multiple target organs with a single drug, bearing in mind the need to offer personalized treatments under the umbrella of precision medicine in all patients with eosinophil-associated diseases (EADs). In addition to reviewing these issues, we also discuss a series of perspectives addressing the management of EAD patients from a multidisciplinary approach, with the collaboration of health professionals from different specialties who manage the different multimorbidities that frequently occur in these patients. We examine the basic principles of care that this multidisciplinary approach must cover and present a multidisciplinary expert opinion regarding the ideal management of patients with EADs, from diagnosis to therapeutic approach and follow-up.

IgE, IgE Receptors and Anti-IgE Biologics: Protein Structures and Mechanisms of Action

The evolution of IgE in mammals added an extra layer of immune protection at body surfaces to provide a rapid and local response against antigens from the environment. The IgE immune response employs potent expulsive and inflammatory forces against local antigen provocation, at the risk of damaging host tissues and causing allergic disease. Two well-known IgE receptors, the high-affinity FcεRI and low-affinity CD23, mediate the activities of IgE. Unlike other known antibody receptors, CD23 also regulates IgE expression, maintaining IgE homeostasis. This mechanism evolved by adapting the function of the complement receptor CD21. Recent insights into the dynamic character of IgE structure, its resultant capacity for allosteric modulation, and the potential for ligand-induced dissociation have revealed previously unappreciated mechanisms for regulation of IgE and IgE complexes. We describe recent research, highlighting structural studies of the IgE network of proteins to analyze the uniquely versatile activities of IgE and anti-IgE biologics.

A newly identified myokine: irisin, and its relationship with chronic spontaneous urticaria and inflammation

Chronic spontaneous urticaria (CSU) is an important dermatological disease involving severe itchy urticaria lesions and/or angioedema. Urticaria and angioedema occur in the community at a rate of 25-30%. Many factors, such as inflammation, have been implicated in the etiology of CSU. Irisin is a newly identified adipocytokine shown by research to exhibit anti-inflammatory properties in addition to its many other effects. The aim of the study was to investigate, for the first time in the literature, the significance of serum irisin levels in patients with CSU. Seventy-eight individuals were evaluated. The study group included 44 patients diagnosed with CSU, and the control group consisted of 34 healthy individuals. Serum samples were collected, and serum irisin, Interleukin-2 (IL-2), Interleukin-3 (IL-3), Tumor Necrosis Factor-alpha (TNF-α), and Interferon-ɣ (IF-ɣ) levels were determined using the enzyme-linked immunosorbent assay (ELISA) method. Irisin was studied for the first time in patients with CSU and exhibited a significantly higher level in the control group than in the patient group (p = 0.020). IL-2, IL-3, and IF-ɣ levels were higher in the CSU group than in the control group, although the results were not statistically significant. Only TNF-α results increased significantly. Correlation analysis was applied to determine the relationships between irisin and IF-ɣ and IL-3 levels. This revealed that the irisin parameter was significantly and positively correlated with IF-ɣ and IL-3 in patients with CSU (r = 0.518, p = 0.016 and r = 0.536, p = 0.022, respectively). This is the first report to evaluate irisin as an inflammatory biomarker in CSU. Irisin levels in patients with CSU were low, suggesting that irisin may pay a role in the pathogenesis of CSU and may be a marker showing the severity of the disease.

Urticaria and Angioedema

Urticaria and angioedema are caused by immunoglobulin E- and non-immunoglobulin E-mediated release of histamine and other inflammatory mediators from mast cells and basophils. Diagnosis is made clinically, and anaphylaxis must be ruled out if urticaria or angioedema is present. A limited nonspecific laboratory workup should be considered unless elements of the history or physical examination suggest specific underlying conditions. The mainstay of treatment is avoidance of triggers when and if triggers are identified. The first-line pharmacotherapy is second-generation H1 antihistamines, which can be titrated to greater than standard doses.

Unveiling chronic spontaneous urticaria pathophysiology through systems biology

BACKGROUND

Chronic spontaneous urticaria (CSU) is a rare, heterogeneous, severely debilitating, and often poorly controlled skin disease resulting in an itchy eruption that can be persistent. Antihistamines and omalizumab, an anti-IgE mAb, are the only licensed therapies. Although CSU pathogenesis is not yet fully understood, mast cell activation through the IgE:high-affinity IgE receptor (FcεRI) axis appears central to the disease process.

OBJECTIVE

We sought to model CSU pathophysiology and identify in silico the mechanism of action of different CSU therapeutic strategies currently in use or under development.

METHODS

Therapeutic performance mapping system technology, based on systems biology and machine learning, was used to create a CSU interactome validated with gene expression data from patients with CSU and a CSU model that was used to evaluate CSU pathophysiology and the mechanism of action of different therapeutic strategies.

RESULTS

Our models reflect the known role of mast cell activation as a central process of CSU pathophysiology, as well as recognized roles for different therapeutic strategies in this and other innate and adaptive immune processes. They also allow determining similarities and differences between them; anti-IgE and Bruton tyrosine kinase inhibitors play a more direct role in mast cell biology through abrogation of FcεRI signaling activity, whereas anti-interleukins and anti-Siglec-8 have a role in adaptive immunity modulation.

CONCLUSION

In silico CSU models reproduced known CSU and therapeutic strategies features. Our results could help advance understanding of therapeutic mechanisms of action and further advance treatment research by patient profile.

Resistant Chronic Spontaneous Urticaria - A Case Series Narrative Review of Treatment Options

Background

Chronic spontaneous urticaria (CSU) can be extremely debilitating to the patient and challenging for the treating clinician. The National Institute of Health and Clinical Excellence (NICE) in the United Kingdom (UK) recommendation of omalizumab for patients who fail to respond to high-dose anti-histamines has improved treatment options and quality of life. However, there is still lack of clear guidelines for treatment of patients resistant to standard and anti-IgE therapies.

Methods

We discuss the therapeutic strategies employed among nine extremely resistant CSU cases and the heterogeneity between guidelines from different societies.

Results

Patients with anti-histamine-resistant urticaria either remained on omalizumab or started on immunosuppressive drugs (dapsone or ciclosporin) when they stopped responding to omalizumab. We used clinical assessment, skin biopsies (when available) and previous published reports to consider dapsone (for predominantly neutrophilic infiltration), or ciclosporin at doses between 2 and 4 mg/kg/day. One patient with ciclosporin-resistant urticaria responded to mycophenolate mofetil. Two patients remain on long-term omalizumab due to its relative safety and efficacy including 1 patient with underlying antibody deficiency where omalizumab was preferred over risks of using immunosuppressive medications.

Conclusions

These case studies bring to light the real-world difficulties in managing patients with resistant CSU and the need for generating the evidence base on alternative therapeutic options such as synergistic use of biologics and immunosuppressive drugs.

Comparison between chronic spontaneous urticaria and chronic induced urticaria on the efficacy of omalizumab treatment: A systematic review and meta-analysis

This meta-analysis aimed to assess the efficacy of omalizumab in the treatment of refractory-to-antihistamines chronic induced urticaria (CIndU) in comparison with that of refractory-to-antihistamines chronic spontaneous urticaria (CSU). We retrieved interventional studies and observational studies on omalizumab efficacy to CIndU patients and efficacy comparison between CSU and CIndU both refractory to H1-antihistamines in electronic databases (accessed till May 2022). The odd ratio (OR) and 95% confidence interval (CI) was calculated with a random-effect model in this meta-analysis. The majority of patients with different CIndU subtypes gained complete or partial response and good safety after omalizumab treatment. A total of five studies with 355 CSU patients and 103 CIndU patients were included for the meta-analysis. There was no significant difference in the efficacy of omalizumab in the treatment of CSU and CIndU (OR -0.83, 95% CI [0.84, 2.21], P > 0.05). Based on the validity of omalizumab in the treatment of various CIndU subtypes and non-differential efficacy between CSU and CIndU, it is reasonable to list omalizumab as a third-line treatment of refractory CIndU.

Novel biologics for treatment of chronic spontaneous urticaria

Chronic idiopathic/spontaneous urticaria (CIU/CSU) causes significant impairments in quality of life and is often unresponsive to antihistamines. Although the anti-IgE mAb omalizumab has been an important addition to the therapeutic armamentarium for the management of patients with CSU, there are still a significant percentage of patients who do not respond to the combination of antihistamines and omalizumab. As a result, additional treatments are needed. With the expanding knowledge of the pathogenesis of CSU and the role of mast cells, novel therapeutic agents targeting unique pathways important in CSU are in development. This review focuses on the rationale behind, and results of, novel therapies trialed in CSU.

Comorbidities of Chronic Urticaria: A glimpse into a complex relationship

Chronic Urticaria (CU) is a chronic inflammatory, predominantly mast cell-driven disease, characterized by the development of wheals and/or angioedema for more than 6 weeks. It affects approximately 1%-5% of the total population worldwide and imposes a substantial burden on health-related quality of life, significantly affecting patients' daily life. The economic impact on the health system is also not negligible, with an estimated cost per patient per year of approximately 2.000 $ in the United States. Although the underlying pathophysiology is not fully explored, autoimmune mechanisms have been proposed, including type I ("autoallergy" by means of autoantibodies to self-antigens) and type IIb (autoimmunity). Atopic, autoimmune, and psychiatric disorders are prevalent comorbidities in both children and adults with Chronic Spontaneous Urticaria (CSU). Although malignancies, cardiovascular diseases and other comorbidities have also been reported as associated diseases in patients with CSU, data remain scarce. It is still unknown whether the aforementioned comorbidities share common pathophysiological mechanisms with specific endotypes of CSU. The current review aims to overview current data on comorbidities of CU, and furthermore to comment on the potential linked pathways underlying these diseases.

Off-Label Benralizumab in Severe Non-Necrotizing Eosinophilic Vasculitis following Critical COVID-19 Disease and in DRESS

Benralizumab is a humanized recombinant mAb that binds to the interleukin 5 receptor (IL-5R) expressed on eosinophils and is approved for the treatment of severe eosinophilic asthma. There are a series of severe eosinophilic disorders that may benefit from this treatment, and it could be a life-saving therapy. In this paper, we present two severe patients with eosinophil-induced diseases that had a good resolution after one dose of Benralizumab 30 mg. The first case is a severe non-necrotizing eosinophilic vasculitis following critical COVID-19 disease and the second case is a DRESS (Drug Rash with Eosinophilia and Systemic Symptoms Syndrome) due to allopurinol. Conclusions: The successful administration of Benralizumab in rare or severe eosinophilic disease could be an option for life-saving therapies when conventional treatments fail.

Urticaria

Urticaria is an inflammatory skin disorder that affects up to 20% of the world population at some point during their life. It presents with wheals, angioedema or both due to activation and degranulation of skin mast cells and the release of histamine and other mediators. Most cases of urticaria are acute urticaria, which lasts ≤6 weeks and can be associated with infections or intake of drugs or foods. Chronic urticaria (CU) is either spontaneous or inducible, lasts >6 weeks and persists for >1 year in most patients. CU greatly affects patient quality of life, and is linked to psychiatric comorbidities and high healthcare costs. In contrast to chronic spontaneous urticaria (CSU), chronic inducible urticaria (CIndU) has definite and subtype-specific triggers that induce signs and symptoms. The pathogenesis of CSU consists of several interlinked events involving autoantibodies, complement and coagulation. The diagnosis of urticaria is clinical, but several tests can be performed to exclude differential diagnoses and identify underlying causes in CSU or triggers in CIndU. Current urticaria treatment aims at complete response, with a stepwise approach using second-generation H1 antihistamines, omalizumab and cyclosporine. Novel treatment approaches centre on targeting mediators, signalling pathways and receptors of mast cells and other immune cells. Further research should focus on defining disease endotypes and their biomarkers, identifying new treatment targets and developing improved therapies.

Omalizumab versus cyclosporin-A for the treatment of chronic spontaneous urticaria: can we define better-responding endotypes?

Background

Chronic Spontaneous Urticaria (CSU) is characterized by recurrent wheals and/or angioedema for longer than 6-weeks. Guidelines recommend Omalizumab (Oma) as first-line and Cyclosporine-A (Cs-A) as second-line treatment in antihistamine resistant CSU. This step-wise algorithm might be time-consuming and costly.

Objective

To determine indicators of response to Oma or Cs-A in CSU patients.

Methods

We retrospectively analyzed data from seven centers in Turkey; the inclusion criteria for patients were to receive both Oma and Cs-A treatment (not concurrently) at some point in time during their follow-up. Clinical and laboratory features were compared between groups.

Results

Among 110 CSU patients; 47 (42.7%) were Oma-responders, 15 (13.6%) were Cs-A-responders, and 24 (21.8%) were both Oma and Cs-A responders and 24 (21.8%) were non-responders to either drug. High CRP levels were more frequent in Cs-A-responders (72.7% vs. 40.3%; p = 0.055). Oma-responders had higher baseline UCT (Urticaria Control Test) scores (6 vs. 4.5; p = 0.045). Responders to both drugs had less angioedema and higher baseline UCT scores compared to other groups (33.3% vs. 62.8%; p = 0.01 and 8 vs. 5; p = 0.017). Non-responders to both drugs had an increased frequency in the female gender and lower baseline UCT scores compared to other groups (87.5% vs. 61.6%; p = 0.017 and 5 vs. 7; p = 0.06).

Study Limitations

Retrospective nature, limited number of patients, no control group, the lack of the basophil activation (BAT) or BHRA (basophil histamine release assay) tests.

Conclusions

Baseline disease activity assessment, which considers the presence of angioedema and disease activity scores, gender, and CRP levels might be helpful to predict treatment outcomes in CSU patients and to choose the right treatment for each patient. Categorizing patients into particular endotypes could provide treatment optimization and increase treatment success.

Pediatric chronic spontaneous urticaria: a brief clinician's guide

INTRODUCTION

Chronic urticaria (CU) appears with daily or intermittent/recurrent wheals with/without angioedema for more than six weeks. When no specific eliciting factors are found, chronic urticaria is defined as spontaneous (CSU). Up to 50% of patients with CSU do not respond to therapy, leading to a prolonged disease course and the need for expensive therapies, impacting the quality of life (QoL) and healthcare resources.

AREAS COVERED

: Diagnosis of CSU is made when other potential causes of chronic urticaria are excluded. CSU therapy aims to achieve complete control of symptoms and normalization of QoL. Current treatment options for urticaria aim to target mast cell mediators such as histamine, or activators, such as autoantibodies. Guidelines recommend starting with second generation antihistamines (sgAHs) and adding omalizumab therapy if symptoms are not controlled. This review aims to provide a practical guide for CSU in the pediatric population.

EXPERT OPINION

: Treatment options for pediatric CSU are primarily based on adult data that have been extrapolated for children. Current guidelines should be re-evaluated based on pediatric data, new biological treatments, and the COVID-19 pandemic. Future research is needed to investigate strategies to personalize current treatments and identify potential predictive biomarkers.

Targeting Downstream Type 2 Cytokines or Upstream Epithelial Alarmins for Severe Asthma

Biologics, including omalizumab, mepolizumab, benralizumab, and dupilumab, targeting downstream IgE, cytokines IL-5, and IL-4/13, respectively, have shown promising effects in terms of reduction in annualized asthma exacerbation rates (AER), oral corticosteroid-sparing effects, improvements in forced expiratory volume in 1 second, and improved Asthma Control Questionnaire scores. However, despite these welcome advances, approximately 30% of patients with severe asthma receiving biologics tailored to their specific downstream type 2 biomarkers, including total IgE, peripheral blood eosinophils, and fractional exhaled nitric oxide, do not experience meaningful improvements in their AER. Instead of blocking downstream cytokines, targeting upstream epithelial alarmins, including IL-33, thymic stromal lymphopoietin, and IL-25, has been proposed to tackle the immunologic heterogeneity of asthma. This review article aims to pragmatically summarize the latest key clinical data on antialarmin therapies in severe asthma and put these findings into context with regard to currently available downstream cytokine blockers.

Insights into urticaria in pediatric and adult populations and its management with fexofenadine hydrochloride

OBJECTIVE

The present narrative review provides a comprehensive update of the current knowledge on urticaria, both in adult and pediatric populations, and on the safety and efficacy of fexofenadine hydrochloride (HCl) as a treatment option.

DATA SOURCE

A literature search was conducted on Embase and Medline.

STUDY SELECTION

Clinical studies published in English and published between 1999 and 2020 were selected.

RESULTS

Although the exact pathogenesis of urticaria is not fully understood, multiple pathways of mast cell activation are discussed to explain the existence of phenotypically different clinical manifestations of urticaria. An overview of the worldwide prevalence of chronic urticaria, including disease burden and patient's quality of life is provided. The impact of urticaria on patient's life differs on the basis of whether its form is acute or chronic, but pharmacological approaches are most often needed to control the disabling symptoms. A summary of the current management of urticaria recommended by different guidelines across countries (Global; European; American; Australian; Asian; Japanese) is presented. Non-sedating, second-generation H₁-antihistamines are the preferred choice of treatment across several guidelines worldwide. Herein, the efficacy and safety of fexofenadine HCl, a representative second-generation H₁-antihistamine approved for the treatment of urticaria, is discussed. The occurrence of urticaria manifestations in COVID-19 patients is also briefly presented.

CONCLUSION

The burden of acute and chronic urticaria is high for patients. Second generation anti-histamines such as fexofenadine HCl can help managing the symptoms.

Cholinergic Urticaria, an Effective and Safe "Off Label" Use of Dupilumab: A Case Report with Literature Review

Cholinergic Urticaria (CholU) is a form of generalized urticaria induced by an increase in core body temperature that activates the sweat reflex. Clinically it is characterized by localized and highly itchy wheals with surrounding erythema and can occur in response to exercise, hot baths and/or emotional stress. Dupilumab is a fully human monoclonal antibody specifically designed to simultaneously inhibit the activity of interleukin-4 (IL-4) and interleukin-13 (IL-13), which play a key role in the inflammation cascade of type 2. We report the case of a 26-year-old man suffering from CholU for 3 years, unresponsive to standard treatment in which off-label therapy was undertaken with Dupilumab, 600 mg subcutaneous as a loading dose and then 300 mg every 15 days. The daily Visual Analogue Scale (VAS) score was used to assess the efficacy of the therapy. Already after the first two administrations, the patient no longer had CholU episodes and resumed regular sporting activity, with a marked improvement in the quality of life. A possible mechanism of Dupilumab in reducing the manifestations of CholU is the blocking of the IL-4 pathway and the expression of the high-affinity IgE receptor (FcεR1) on B cells, mast cells (MCs) and basophils. By decreasing the production of FcεR1, the adhesion of IgE to the surface of MCs decreases with consequent reduction of MCs activation and histamine release. Further experience and large-scale studies may be needed to establish whether Dupilumab can be a therapeutic alternative in CholU, especially in patients who do not respond to standard treatment.

The ingenious mast cell: Contemporary insights into mast cell behavior and function

Mast cells are (in)famous for their role in allergic diseases, but the physiological and pathophysiological roles of this ingenious cell are still not fully understood. Mast cells are important for homeostasis and surveillance of the human system, recognizing both endogenous and exogenous agents, which induce release of a variety of mediators acting on both immune and non-immune cells, including nerve cells, fibroblasts, endothelial cells, smooth muscle cells, and epithelial cells. During recent years, clinical and experimental studies on human mast cells, as well as experiments using animal models, have resulted in many discoveries that help decipher the function of mast cells in health and disease. In this review, we focus particularly on new insights into mast cell biology, with a focus on mast cell development, recruitment, heterogeneity, and reactivity. We also highlight the development in our understanding of mast cell-driven diseases and discuss the development of novel strategies to treat such conditions.

Quality of life in patients with allergic and immunologic skin diseases: in the eye of the beholder

Allergic and immunologic skin diseases negatively impact the quality of life (QoL) of affected patients with detrimental consequences. Nonetheless, in everyday clinical practice the evaluation of QoL is often overlooked. Considering the increasing prevalence of atopic dermatitis, allergic contact dermatitis, hereditary angioedema, cutaneous mastocytosis, and urticaria, it is essential to determine the effects of allergic and immunologic skin diseases on QoL. A joint meeting (GET TOGETHER 2021) of the Italian Society of Allergology, Asthma and Clinical Immunology (SIAAIC) and the Italian Society of Allergological, Occupational and Environmental Dermatology (SIDAPA) aimed to summarize the features of the main QoL tools used in these diseases and to describe the extent of QoL impairment as well as the impact of treatments on QoL, particularly biologic therapies. The assessment of QoL in patients with allergic and immunologic skin diseases relies on generic, organ-specific and disease-specific questionnaires. While generic and organ-specific questionnaires allow comparison between different diseases, disease-specific questionnaires are designed and validated for specific cohorts: the QoL Index for Atopic Dermatitis (QoLIAD) and the Childhood Atopic Dermatitis Impact Scale (CADIS) in atopic dermatitis, the ACD-11 in allergic contact dermatitis, the Angioedema QoL Questionnaire (AE-QoL) and the Hereditary Angioedema QoL questionnaire (HAE-QoL) in hereditary angioedema, the Mastocytosis QoL Questionnaires (MCQoL e MQLQ) in cutaneous mastocytosis, and the Chronic Urticaria QoL questionnaire (CU-Q2oL) in urticaria. Among the many factors that variably contribute to QoL impairment, pruritus can represent the leading cause of patient discomfort. Biologic therapies significantly ameliorate QoL in atopic dermatitis, hereditary angioedema, mastocytosis and chronic urticaria. In general, adequate management strategies are essential for improving QoL in patients with allergic and immunologic skin diseases.

Sustained safety and efficacy of ligelizumab in patients with chronic spontaneous urticaria: A one-year extension study

BACKGROUND

Ligelizumab, a next-generation, humanized anti-immunoglobulin E (IgE) monoclonal antibody is in development as a treatment for patients with chronic spontaneous urticaria, whose symptoms are inadequately controlled with standard-of-care therapy.

OBJECTIVE

To evaluate the long-term safety and re-treatment efficacy of ligelizumab 240 mg in patients who completed the core study and extension study.

METHODS

This open-label, single-arm, long-term Phase 2b extension study was designed to assess patients who were previously administered various doses of ligelizumab, omalizumab or placebo in the Phase 2b, dose-finding core study and who presented with active disease after Week 32. In the extension study, patients received ligelizumab 240 mg subcutaneously every 4 weeks, for 52 weeks and were monitored post-treatment for 48 weeks.

RESULTS

Overall, ligelizumab was well-tolerated with no newly identified safety signals. A total of 95.4% (226/237) screened patients received ligelizumab 240 mg in the extension study; 84.1% (190/226) of patients experienced at least one treatment-emergent adverse event. Most reported events were mild (41.6%) or moderate (35.8%) and mostly unrelated to the study treatment. At Week 12, 46.5% of patients had a complete response increasing to 53.1% after 52 weeks. Following 52 weeks of extension study treatment, 75.8% (95% confidence interval, 69.9, 81.3) of patients had cumulative complete responses. The median time to relapse in complete responders was 38 weeks.

CONCLUSION

The long-term safety profile of ligelizumab 240 mg in patients with chronic spontaneous urticaria was consistent with the core study and re-treatment efficacy was shown.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02477332 and NCT02649218.

British Association of Dermatologists guidelines for the management of people with chronic urticaria 2021

The overall objective of the guideline is to provide up-to-date, evidence-based recommendations for the management of urticaria. The document aims to: offer an appraisal of all relevant literature up to March 2020, focusing on any key developments address important, practical clinical questions relating to the primary guideline objective provide guideline recommendations and if appropriate research recommendations The guideline is presented as a detailed review with highlighted recommendations for practical use in primary, secondary and tertiary care, in addition to an updated Patient Information Leaflet (PIL; available on the BAD Skin Health Information website, https://www.skinhealthinfo.org.uk/a-z-conditions-treatments/).

Immunological Targets of Biologic Drugs in Allergic Skin Diseases in Children

Atopic dermatitis and urticaria are two invalidating skin disorders that are very common in children. Recent advances in the understanding of their specific intracellular molecular pathways have permitted the development of precise biological molecules, targeting inflammatory mediators and arresting the pathogenetic pathways of skin diseases. Many biologics with promising results have been studied, although few are currently approved in children. In this review, we aim to provide the latest evidence about the use, indications, efficacy and safety of biologic therapies to treat atopic dermatitis and chronic urticaria in children and adolescents.

Case of postural urticaria in a 14-year-old girl

Chronic inducible urticaria (CIndU) is a subset of chronic urticaria that has an identifiable trigger. We present a case of postural urticaria induced by change in position in a 14-year-old girl. The patient's CIndU was not adequately managed with both antihistamine and omalizumab treatment, indicating a recalcitrant form of CIndU.

Evaluation of Pharmacologic Treatments for H1 Antihistamine-Refractory Chronic Spontaneous Urticaria: A Systematic Review and Network Meta-analysis

Importance

The comparative benefits and harms of all available treatments for H1 antihistamine-refractory chronic spontaneous urticaria (CSU) have not been established.

Objective

To evaluate different treatment effects of pharmacologic treatments among patients with H1 antihistamine-refractory CSU.

Data Sources

Searches were conducted of MEDLINE, Embase, PubMed, Cochrane Library, Web of Science, Scopus, and CINAHL from inception to April 19, 2021, with no language restrictions. Gray literature from Google Scholar, ongoing trial registers, and preprint reports was added to the searches of electronic databases.

Study Selection

Randomized clinical trials using validated measurement tools that investigated the benefits and harms of pharmacologic treatments among adolescent or adult patients with CSU who had an inadequate response to H1 antihistamines were screened for inclusion independently by 2 investigators.

Data Extraction and Synthesis

Two investigators independently extracted study data according to the predefined list of interests. A random-effects model was used to calculate the network estimates reported as standardized mean differences and odds ratios with corresponding 95% CIs.

Main Outcomes and Measures

The primary outcomes that reflect the patient's perspective included changes in urticaria symptoms from baseline and unacceptability of treatment (all-cause dropouts).

Results

Twenty-three randomized clinical trials with 2480 participants that compared 18 different interventions or dosages and placebo were included. The standardized mean differences for change in urticaria symptoms were -1.05 (95% CI, -1.37 to -0.73) for ligelizumab, 72 mg; -1.07 (95% CI, -1.39 to -0.75) for ligelizumab, 240 mg; -0.77 (95% CI, -0.91 to -0.63) for omalizumab, 300 mg; and -0.59 (95% CI, -1.10 to -0.08) for omalizumab, 600 mg. No significant differences in treatment unacceptability were observed. With respect to benefits and harms, the network estimates illustrated that the most efficacious treatments were achieved with ligelizumab, 72 or 240 mg (large beneficial effect) and omalizumab, 300 or 600 mg (moderate beneficial effect).

Conclusions and Relevance

The findings in this meta-analysis suggest that the biologic agents ligelizumab, 72 or 240 mg, and omalizumab, 300 or 600 mg, can be recommended as effective treatments for patients with CSU who have had an inadequate response to H1 antihistamines. Head-to-head trials with high methodologic quality and harmonized design and outcome definitions are needed to help inform subsequent international guidelines for the management of CSU.

Prominent Role of Type 2 Immunity in Skin Diseases-Beyond Atopic Dermatitis

Type 2 immunity, illustrated by T helper 2 lymphocytes (Th2) and downstream cytokines (IL-4, IL-13, IL-31) as well as group 2 innate lymphoid cells (ILC2), is important in host defense and wound healing.¹ The hallmark of type 2 inflammation is eosinophilia and/or high IgE counts and is best recognized in atopic diathesis. Persistent eosinophilia, such as seen in hypereosinophilic syndromes, leads to fibrosis and hence therapeutic Type 2 inhibition in fibrotic diseases is of high interest. Furthermore, as demonstrated in cutaneous T cell lymphoma, advanced disease is characterized by Th1 to Th2 switch allowing cancer progression and immunosuppression. Development of targeted monoclonal antibodies against IL-4Rα (eg, dupilumab) led to a paradigm shift for the treatment of atopic dermatitis (AD) and stimulated research to better understand the role of Type 2 inflammation in other skin conditions. In this review, we summarize up to date knowledge on the role of Type 2 inflammation in skin diseases other than AD and highlight whether the use of Type 2 targeted therapies has been documented or is being investigated in clinical trials. This manuscript reviews the role of Type 2 inflammation in dermatitis, neurodermatitis, IgE-mediated dermatoses (eg, bullous pemphigoid, chronic spontaneous urticaria), sclerodermoid conditions and skin neoplasms.

The Role of Coagulation and Complement Factors for Mast Cell Activation in the Pathogenesis of Chronic Spontaneous Urticaria

Chronic spontaneous urticaria (CSU) is a common skin disorder characterized by an almost daily recurrence of wheal and flare with itch for more than 6 weeks, in association with the release of stored inflammatory mediators, such as histamine, from skin mast cells and/or peripheral basophils. The involvement of the extrinsic coagulation cascade triggered by tissue factor (TF) and complement factors, such as C3a and C5a, has been implied in the pathogenesis of CSU. However, it has been unclear how the TF-triggered coagulation pathway and complement factors induce the activation of skin mast cells and peripheral basophils in patients with CSU. In this review, we focus on the role of vascular endothelial cells, leukocytes, extrinsic coagulation factors and complement components on TF-induced activation of skin mast cells and peripheral basophils followed by the edema formation clinically recognized as urticaria. These findings suggest that medications targeting activated coagulation factors and/or complement components may represent new and effective treatments for patients with severe and refractory CSU.

Thymic Stromal Lymphopoietin in Cutaneous Immune-Mediated Diseases

Thymic stromal lymphopoietin (TSLP) was initially demonstrated to be critical in regulating inflammatory responses among various allergic disorders (such as atopic dermatitis, food allergy, and asthma). Although two isoforms (short form and long form) of TSLP have been demonstrated in human tissues, the long form of TSLP (lfTSLP) is strongly implicated in the pathogenesis of allergies and cutaneous immune-mediated diseases. The immunomodulatory activity of lfTSLP varies widely, driving T helper (Th) cells polarizing Th2 and Th17 immune responses and inducing itch. Moreover, lfTSLP is closely associated with skin fibrosis, epidermal hyperplasia, angiogenesis, and homeostatic tolerogenic regulations. This review highlights significant progress from experimental and clinical studies on lfTSLP in cutaneous immune-mediated diseases (atopic dermatitis, psoriasis, bullous pemphigoid, systemic sclerosis, chronic spontaneous urticaria, Behçet's disease, vitiligo, rosacea, systemic lupus erythematosus, and alopecia areata). We also offer original insights into the pleiotropic properties of the cytokine TSLP in various pathophysiological conditions, with significant clinical implications of TSLP-targeted therapies for immune-mediated skin diseases in the future.