Chronic Spontaneous Urticaria: Pathogenesis and Treatment Considerations

Mapping the intellectual structure of the research of omalizumab in chronic spontaneous urticaria: A bibliometric analysis

Background

The guidelines for treating chronic spontaneous urticaria (CSU) recommend using the IgE-targeted biologic omalizumab in patients with antihistamine-refractory disease.

Objective

Our aim was to present a bibliometric review of publications related to omalizumab and CSU over the past 2 decades.

Methods

Relevant publications from 2003 to 2022 were extracted from the Science Citation Index-Expanded (SCI-EXPANDED) database in the Web of Science Core Collection database as of January 8, 2023. We utilized CiteSpace (version 6.1.R3), VOSviewer (version 1.6.18), and the R package (version 4.2.1) to analyze and visualize the data. The R package bibliometrix (version 4.2.1) was also used.

Results

Between 2003 and 2022, a total of 566 articles on omalizumab and CSU were published. Since 2014, there has been a rapid increase in publication output. According to the collaboration network, the most influential country, institute, and scholar were the United States, Charité Universitätsmedizin Berlin, and Marcus Maurer, respectively. The study identified the Journal of Allergy and Clinical Immunology: In Practice as the most productive journal and the Journal of Allergy and Clinical Immunology as the most cocited journal. The analysis of key words revealed the presence of high-frequency terms such as angioedema, IgE, treatment, anti-IgE, asthma, and atopic dermatitis. Moreover, recent studies in this area have concentrated mainly on biomarkers, dupilumab, and coronavirus 2019 (COVID-19).

Conclusion

There has been a growing interest in the use of omalizumab in CSU in recent years. The current trending topics in this research are the identification of biomarkers and the development of new mAbs for the treatment of CSU.

Treatment of acute urticaria: A systematic review

There are only a few clinical trials which address the treatment of acute urticaria (AU). Especially, the added value of systemic corticosteroids to antihistamines is unclear in treatment of severe AU. To review the existing evidence-based approaches for AU treatment. A systematic electronic search was done in PubMed and Web of Science to retrieve all studies on the treatment of patients with AU. A descriptive synthesis was conducted based on the PRISMA statement. Quality assessment was independently performed by both reviewers ('Cochrane risk-of-bias tool' for RCTs). Ten randomized controlled trials (RCTs) (n = 857 participants) were included. Four studies assessed corticosteroid effectiveness added to antihistamines and six studies compared the efficacy of H1 and/ or H2 -antihistamines. The addition of corticosteroid (prednisone) to an antihistamine (levo)cetirizine did not improve symptoms of AU compared to antihistamine alone in two out of three RCTs. The combination of diphenhydramine (50 mg, IV) and ranitidine (50 mg, IV) or cimetidine (300 mg, IV) was most efficient for relief of urticaria in two out of five studies. Most frequent adverse effects were sedation and drowsiness. Recent guidelines on urticaria treatment mainly focus on chronic urticaria rather than on AU. Moreover, only few, small RCTs provide evidence for the management of AU. Thus, the state-of-the-art management of this frequent condition remains unclear. The addition of corticosteroids to an antihistamine as treatment for AU needs to be further investigated. Well-designed, high-quality interventional trials are needed to establish evidence-based treatment guidelines for AU.

Dupilumab in patients with chronic spontaneous urticaria (LIBERTY-CSU CUPID): Two randomized, double-blind, placebo-controlled, phase 3 trials

BACKGROUND

Chronic spontaneous urticaria (CSU) is a chronic inflammatory disease characterized by recurrent pruritic wheals (hives) and/or angioedema. Patients with CSU could remain symptomatic despite standard-of-care H1 antihistamines (H1-AH) or anti-IgE (omalizumab) treatment. Dupilumab blocks IL-4/IL-13 signaling and is approved for multiple type 2/atopic indications.

OBJECTIVE

We conducted two phase 3, randomized, placebo-controlled, double-blind trials comparing dupilumab with placebo in patients with symptomatic CSU despite H1-AH.

METHODS

In LIBERTY-CSU CUPID Study A, patients were omalizumab-naive (n = 138, aged ≥6 years). In Study B, patients were omalizumab-intolerant/incomplete responders (n = 108, aged ≥12 years). The primary end point was either change from baseline over 7 days in the Urticaria Activity Score (UAS7) or Itch Severity Score (ISS7) at week 24, with the other as a key secondary end point, depending on regional regulatory requirements. Studies were pooled for safety assessment.

RESULTS

In Study A, UAS7 and ISS7 improved with dupilumab versus placebo (difference -8.5 [95% CI, -13.2 to -3.9; P = .0003] and -4.2 [95% CI, -6.6 to -1.8; P = .0005]). In Study B, tested at α = 0.043 after interim analysis, UAS7 improved (difference -5.8 [95% CI, -11.4 to -0.3; P = .0390]), with a numerical trend in ISS7 (difference -2.9 [95% CI, -5.7 to -0.07; nominal P = .0449, not significant]). Pooled safety data were consistent between dupilumab and placebo and with the known dupilumab safety profile.

CONCLUSIONS

Dupilumab reduced urticaria activity by reducing itch and hives severity in omalizumab-naive patients with CSU uncontrolled with H1-AH. Although the primary end point for Study B was not met, dupilumab effects were small in patients who were omalizumab-intolerant/incomplete responders.

Evaluation of Pediatric Chronic Urticaria with Emphasis on Clinical and Laboratory Characteristics and Treatment Response to Omalizumab: A Real-Life Experience from a Tertiary Allergy Center

Pediatric data on the clinical and etiologic features, treatment response, and use of omalizumab for chronic urticaria (CU) are quite limited. The aim of this study was to evaluate the clinical and demographic characteristics, laboratory findings, and response to treatment of CU in children. Children with a diagnosis of CU between 2019 and 2023 were included in the study. Information on demographic characteristics, clinical features, laboratory tests, provocation tests for inducible urticaria, urticaria activity scores (UAS7), and treatment responses were obtained from patients' medical records. A total of 150 children (50.7% male) with CU were enrolled in the study. A total of 14 (9.3%) patients had autoimmune diseases of which 11 (7.3%) had autoimmune thyroiditis. Overall, 97 (64.7%) patients had chronic spontaneous urticaria (CSU) and 53 (35.3%) had chronic inducible urticaria. A total of 16 patients who remained symptomatic despite high-dose antihistamines were treated with omalizumab, with a good response in 13 (81.3%) and a partial response in 3 (18.7%) patients. CSU accounts for the majority of pediatric CU, with the etiology being in part related to an autoimmune background. This study provides an overview of CU in children and demonstrates the safety and efficacy of treatment with omalizumab.

Brain network mechanism of acupuncture for chronic spontaneous urticaria: a functional magnetic resonance imaging study protocol

Introduction

Chronic spontaneous urticaria (CSU) is a common skin condition that can significantly impact patients' quality of life. Although studies have demonstrated the efficacy of acupuncture in treating CSU, the underlying mechanisms remain unclear. Dysfunction within the brain's default mode network (DMN) represents a fundamental characteristic of central pathological changes associated with CSU. Therefore, it is hypothesized that improving brain network dysfunction could serve as a key mechanism through which acupuncture exerts its therapeutic effects. This study aims to provide evidence supporting this hypothesis.

Methods and analysis

This study, a parallel, randomized, sham-controlled functional neuroimaging investigation will be conducted in China. We aim to enroll 50 patients with CSU and 25 healthy controls, distributing them evenly between the acupuncture and sham acupuncture groups in a 1:1 ratio. The total observation period will span 6 weeks, including 2 weeks designated for the baseline phase and 4 weeks allocated for the clinical treatment phase. Prior to treatment, all participants will undergo magnetic resonance scanning, clinical index detection, and microbiota collection. Following treatment, the patients with CSU will be retested for these indicators. Using resting-state functional connectivity (rsFC) analysis, dynamic Functional Connection (dFC) analysis, and brain microstate extraction technology combined with correlation analysis of microbiota and clinical indicators, the regulatory mechanism of acupuncture on the brain network of CSU will be evaluated from multiple dimensions.

Ethics and dissemination

This trial was approved by the Biomedical Ethics Review Committee of the West China Hospital, Sichuan University (No. 2022-1255). Each participant will provide written informed consent to publish any potentially identifiable images or data.Clinical trial registrationhttps://www.chictr.org.cn/, identifier: ChiCTR2200064563.

Increased Risk of Systemic Lupus Erythematosus in Patients with Chronic Urticaria: A Systematic Review and Meta-analysis

Introduction

The association between systemic lupus erythematosus (SLE) and chronic urticaria (CU) has been suggested in the literature although the amount of evidence is still relatively limited. We aimed to combine all available studies on this association using systematic review and meta-analysis technique.

Methods

Potentially eligible studies were identified from Medline and EMBASE from inception to February 2023 using search strategy that comprised of terms for "chronic urticaria" and "systemic lupus erythematosus". The eligible study must consist of one group of patients with CU and another group of comparators without CU and must compare the prevalence of SLE in each group and report effect size with 95% confidence intervals (95% CIs). We extracted such data from each study to calculate a pooled odds ratio using the generic inverse variance method with random-effect model. Funnel plot was used to evaluate publication bias. Newcastle-Ottawa Scale was used to appraise the methodological quality of the included studies.

Results

A total of 5,155 articles were identified. After two rounds of independent review by four investigators, five studies met the eligibility criteria and were included in the meta-analysis. The meta-analysis found an increased prevalence of SLE among patients with CU compared with individuals without CU with the pooled odds ratio of 5.03 (95% CI, 2.57-9.85, I2 of 93%).

Conclusion

This systematic review and meta-analysis found that patients with CU had a significantly increased risk of SLE compared to individuals without CU.

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.

Monoclonal Antibodies in Treating Chronic Spontaneous Urticaria: New Drugs for an Old Disease

Background: H1-antihistamines (H1AH) represent the current mainstay of treatment for chronic spontaneous urticaria (CSU). However, the response to H1AH is often unsatisfactory, even with increased doses. Therefore, guidelines recommend the use of omalizumab as an add-on treatment in refractory CSU. This paved the way for the investigation of targeted therapies, such as monoclonal antibodies (mAbs), in CSU. Methods: A literature review was conducted including papers published between 2009 and 2022 and ongoing trials about the efficacy and safety of mAbs as treatment for CSU. Results: Twenty-nine articles, a trial with preliminary results, and seventeen ongoing or completed clinical trials on the use of mAbs in CSU were included. Randomized controlled trials (RCTs), meta-analysis, and real-life studies have proven the effectiveness and safety of omalizumab as a third-line treatment in refractory CSU. However, a percentage of patients remain unresponsive to omalizumab. Therefore, other mAbs, targeting different pathways, have been used off-label in case series and others are under investigation in RCTs. Most of them have showed promising results. Conclusions: Omalizumab remains the best choice to treat refractory CSU. Although results from other mAbs seem to be encouraging to achieve symptom control in refractory CSU, thus improving patients’ QoL, RCTs are needed to confirm their effectiveness and safety.

Neuro-allergology: Mast cell-nerve cross-talk

Mast cells (MCs) are derived from hematopoietic stem cells in the bone marrow, and their maturation is regulated by the tissue environment, such as the skin, lung and gut, leading to host defense. Peripheral nerve fibers located in various tissues are involved in diverse physiological and pathological processes. Anatomical relationships between MCs and nerve fibers were reported to have been observed in various organs. Moreover, MCs are positive for a large number of receptors for classical neurotransmitters (e.g., acetylcholine and corticotropin-releasing hormone) and neuropeptides (e.g., substance P, calcitonin gene-related peptides and hemokinin), and MC's functions are regulated by those nerve-derived factors. Also, histamine and proteases produced and released by MCs modulate nerve fiber functions. This functional cross-talk between MCs and nerve fibers can play physiological and pathological roles. MCs are key effector cells of allergic inflammation, such as atopic dermatitis, airway inflammation and food allergy. Here, we summarize and discuss the molecular mechanisms underlying the functional and anatomical cross-talk between MCs and nerve fibers in allergic inflamed tissues.

A novel detection method for cross-linking of IgE-receptors by autoantibodies in chronic spontaneous urticaria

BACKGROUND

Autoantibodies (AAbs) against immunoglobulin E (IgE) antibodies (Abs) and their high-affinity receptor alpha subunits (FcεRIα) are key factors in the elicitation of type IIb autoimmune chronic spontaneous urticaria (type IIb aiCSU). In this study, we aimed to develop a new method to detect functional anti-FcεRIα and anti-IgE AAbs, which can crosslink the plural FcεRІα molecules and IgE Abs on the surface of mast cells and basophils, in sera from aiCSU patients using the amplified luminescence proximity homogeneous assay (Alpha).

METHODS

Sera were obtained from 14 aiCSU patients, as diagnosed by recurrent chronic spontaneous urticaria episodes and positive results for the autologous serum skin test and/or histamine release test (HRT). The AAbs to FcεRIα and IgE Abs were determined in sera from aiCSU patients using enzyme-linked immunosorbent assay (ELISA) and Alpha by cross-linking (AlphaCL) of IgE Abs and/or FcεRІα.

RESULTS

Serum anti-FcεRIα and anti-IgE AAb levels were not significantly different between aiCSU patients and healthy subjects in ELISA. Anti-FcεRIα AAbs were detected in 10 of 14 aiCSU patients who displayed positive (5/5) and negative (5/9) results in the HRT for anti-FcεRIα AAbs by AlphaCL, whereas no signals were observed in healthy subjects. Additionally, anti-IgE AAbs were detected in two of four aiCSU patients who displayed positive results in the HRT for anti-IgE AAbs.

CONCLUSIONS

A new assay method using AlphaCL can detect anti-FcεRIα and anti-IgE AAbs with FcεRIα- and IgE-crosslinking abilities in sera from aiCSU patients. This simple and practical assay method may be available as a diagnostic tool for urticaria patients.

Knowledge, attitudes, and practices associated with personal health care on urticaria in peripheral health facilities of Yaoundé, Cameroon (Sub-Saharan Africa)

BACKGROUND

Urticaria is an acute or chronic inflammatory dermatosis that is characterized by erythematous, edematous, itchy, and transient urticarial plaques that cover the skin and mucous membranes. The aim of this study was to evaluate the knowledge of consulting staff on urticaria in Yaoundé, Cameroon, as well as the attitudes and practices resulting from it.

METHODS

We conducted a descriptive cross-sectional study. The participants were enrolled from January to April 2017 in 25 health facilities in Yaoundé, Cameroon. The sample consisted of health personnel including doctors, nurses, and nursing aids. Data were collected using a self-administered questionnaire; the evaluation scores for each heading were established. Data processing was done using the SPSS software Version 21.

RESULTS

We recruited 101 participants, with a sex ratio of 0.4 (73/101 were female); 44.6% of the participants were doctors, and 50% of our participants had less than 5 years of professional experience. The level of knowledge on urticaria was insufficient for 40.6% of the staff enrolled. Attitudes towards urticaria were incorrect for 36.6% of staff, and 95% of our sample had harmful practices.

CONCLUSION

Our study reveals that skills of the health care provider regarding urticaria are generally poor and do not enable them to ensure an adequate management of the disease.

The challenges of chronic urticaria part 2: Pharmacological treatment, chronic inducible urticaria, urticaria in special situations

This is Part 2 of an updated follow-up review of the World Allergy Organization (WAO) position paper on the diagnosis and treatment of urticaria and angioedema. Since that document was published, new advances in the understanding of the pathogenesis of chronic urticaria, and greater experience with the use of biologics in patients with severe refractory disease, mainly omalizumab, have been gained. For these reasons, WAO decided to initiate an update targeted to general practitioners around the world, incorporating the most recent information on epidemiology, immunopathogenesis, comorbidities, quality of life, clinical case presentations, and the management of chronic spontaneous and chronic inducible urticaria, and urticaria in special situations such as childhood and pregnancy. A special task force of WAO experts was invited to write the different sections of the manuscript, and the final document was approved by the WAO Board of Directors. This paper is not intended to be a substitute for current national and international guidelines on the management of urticaria and angioedema, but to provide an updated simplified guidance for physicians around the world who have to manage patients with this common ailment.

Fenebrutinib in H1 antihistamine-refractory chronic spontaneous urticaria: a randomized phase 2 trial

Bruton's tyrosine kinase (BTK) is crucial for FcεRI-mediated mast cell activation and essential for autoantibody production by B cells in chronic spontaneous urticaria (CSU). Fenebrutinib, an orally administered, potent, highly selective, reversible BTK inhibitor, may be effective in CSU. This double-blind, placebo-controlled, phase 2 trial (EudraCT ID 2016-004624-35 ) randomized 93 adults with antihistamine-refractory CSU to 50 mg daily, 150 mg daily and 200 mg twice daily of fenebrutinib or placebo for 8 weeks. The primary end point was change from baseline in urticaria activity score over 7 d (UAS7) at week 8. Secondary end points were the change from baseline in UAS7 at week 4 and the proportion of patients well-controlled (UAS7 ≤ 6) at week 8. Fenebrutinib efficacy in patients with type IIb autoimmunity and effects on IgG-anti-FcεRI were exploratory end points. Safety was also evaluated. The primary end point was met, with dose-dependent improvements in UAS7 at week 8 occurring at 200 mg twice daily and 150 mg daily, but not at 50 mg daily of fenebrutinib versus placebo. Asymptomatic, reversible grade 2 and 3 liver transaminase elevations occurred in the fenebrutinib 150 mg daily and 200 mg twice daily groups (2 patients each). Fenebrutinib diminished disease activity in patients with antihistamine-refractory CSU, including more patients with refractory type IIb autoimmunity. These results support the potential use of BTK inhibition in antihistamine-refractory CSU.

The HLA-B*13:01 and the dapsone hypersensitivity syndrome in Korean and Asian populations: genotype- and meta-analyses

BACKGROUND

The human leukocyte antigen (HLA)-B*13:01 was reported as an important risk factor for dapsone hypersensitivity syndrome (DHS) in Chinese and Thai populations.

RESEARCH DESIGN AND METHODS

From the Korean nationwide registry, seven subjects with previous DHS were included. Their HLA allele/phenotype frequencies were compared with 8 dapsone-tolerant subjects recruited from a single institution, and general population (n = 485) in Korea. The authors also performed a meta-analysis with these data using previous Chinese and Thai studies.

RESULTS

Among the seven DHS subjects, 85.7% presented with the HLA-B*13:01 allele. The HLA-C*03:04, HLA-DRB1*12:02 (both in linkage disequilibrium with HLA-B*13:01), and HLA-A*02:01 alleles were also presented in 85.7%, 71.4%, and 71.4%, respectively. Subjects with HLA-B*13:01 were susceptible to developing DHS compared to dapsone-tolerant controls (odds ratio [OR]: 73.667) and the Korean general population (OR: 139.500). HLA-C*03:04 (OR: 40.935), HLA-DRB*12:02 (OR: 36.613), and HLA-A*02:01 (OR: 5.862) showed similar results. In meta-analysis, HLA-B*13:01 was associated with dapsone-induced hypersensitivity (overall OR: 42.692), and subgroup analyses according to the control types demonstrated similar results (OR:43.694 and 41.866, respectively).

CONCLUSIONS

Similar to previous Asian population studies, HLA-B*13:01 is significantly associated with the risk of DHS in Korea. These associations may be useful for preventing DHS and improving drug safety.

Advances in the pathogenesis representing definite outcomes in chronic urticaria

PURPOSE OF REVIEW

We reviewed in this article, the recent advances in CSU physiopathology and potential clinical and laboratory biomarkers in CSU.

RECENT FINDINGS

In addition to the central role of mast cells in urticaria physiopathology, increased interest in basophils has arisen. Recent data corroborate the autoimmunity pathway as one of the main pathways in mast cell activation. The association of inflammatory cytokines, heat shock proteins and staphylococcal infection with CSU are also reviewed. C-reactive protein, D-dimers, autologous serum skin test, IgE levels and FcεRI expression in basophils have shown their potential as biomarkers for disease duration, activity, severity and/or response to treatment.

SUMMARY

A comprehensive understanding of chronic spontaneous urticaria mechanisms is essential to find novel biomarkers and treatments. The use of these biomarkers in clinical practice will guide us in choosing the best treatment option for our patients.

Treatment of urticaria: a clinical and mechanistic approach

PURPOSE OF REVIEW

This manuscript describes the recommended therapy of chronic spontaneous urticaria based on our understanding of the pathogenesis of hive formation. Thus, the mechanism of action of each medication is elaborated in addition to a discussion of clinical utility.

RECENT FINDINGS

The main drugs are antihistamines, omalizumab, and cyclosporine with a success rate of 40-55, 65-80, and 70-80%, respectively. Used in sequence, over 90% of patients can be successfully treated. The addition of omalizumab represents a major advance because of its efficacy, easy utility, and favorable side-effect profile. The interaction with IgE eliminates any reaction with antigens to which it might be directed, down regulates IgE receptors on mast cells and basophils, and leads to down-regulation of mast cell functions with amelioration of hives.

SUMMARY

The use of antihistamines in high dosage (at least four times a day) is effective in close to half the patients with CSU. For antihistamine resistance, the use of omalizumab has revolutionized therapy of antihistamine-resistant cases because of its efficacy and excellent side-effect profile. If the response is insufficient, cyclosporine is the next choice. Patients should be monitored regarding any adverse effects on blood pressure or renal function. All these are far safer than extended use of corticosteroid.

New phenotypes in hypersensitivity reactions to nonsteroidal anti-inflammatory drugs

PURPOSE OF REVIEW

Nonsteroidal anti-inflammatory drug (NSAID) is one of the most frequently prescribed medications in the medical field, and hypersensitivity to NSAID is a common adverse drug reaction encountered. However, NSAID hypersensitivity presents a variety of symptoms caused by diverse pharmacological and immunological mechanisms.

RECENT FINDINGS

Owing to the heterogeneity of the disease, a new concept for the classification of NSAID hypersensitivity has recently been proposed to diagnose and manage NSAID hypersensitivity for personalized treatment. Acute and delayed reactions were distinguished in this classification, and identification of symptoms and speculation of putative mechanisms help physicians make the right diagnosis. NSAID-exacerbated respiratory disease is a noticeable phenotype of NSAID hypersensitivity that involves upper airway comorbidities (chronic rhinosinusitis with nasal polyps) as well as asthmatic features. The cutaneous phenotypes of NSAID hypersensitivity occur, and cross-reactivity with other types of NSAID should be considered in establishing a proper diagnosis. Hypersensitivity to a single NSAID can present urticaria/angioedema and anaphylaxis, in which an IgE-mediated immune response is suggested to be a prime mechanism. Management of NSAID hypersensitivity reactions includes avoidance, pharmacological treatment following standard guidelines, and aspirin desensitization.

SUMMARY

The classification, diagnosis, and management of NSAID hypersensitivity should be individually reached by identifying its phenotype.

The KAAACI/KDA Evidence-Based Practice Guidelines for Chronic Spontaneous Urticaria in Korean Adults and Children: Part 1. Definition, Methodology and First-line Management

Chronic spontaneous urticaria (CSU) is defined as the occurrence of spontaneous wheals, angioedema, or both for >6 weeks in the absence of specific causes. It is a common condition associated with substantial disease burden both for affected individuals and societies in many countries, including Korea. CSU frequently persists for several years and requires high-intensity treatment; therefore, patients experience deteriorations in quality of life and medication-associated complications. During the last decade, there have been major advances in the pharmacological treatment of CSU and there is an outstanding need for evidence-based guidelines that reflect clinical practice in Korea. The guidelines reported here represent a joint initiative of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Dermatological Association, and aim to provide evidence-based guidance for the management of CSU in Korean adults and children. In Part 1, disease definition, guideline scope and development methodology as well as evidence-based recommendations on the use of antihistamines and corticosteroids are summarized.

Ligelizumab for Chronic Spontaneous Urticaria

BACKGROUND

In the majority of patients with chronic spontaneous urticaria, most currently available therapies do not result in complete symptom control. Ligelizumab is a next-generation high-affinity humanized monoclonal anti-IgE antibody. Data are limited regarding the dose-response relationship of ligelizumab and the efficacy and safety of ligelizumab as compared with omalizumab and placebo in patients who have moderate-to-severe chronic spontaneous urticaria that is inadequately controlled with H₁-antihistamines at approved or increased doses, alone or in combination with H₂-antihistamines or leukotriene-receptor antagonists.

METHODS

In a phase 2b dose-finding trial, we randomly assigned patients to receive ligelizumab at a dose of 24 mg, 72 mg, or 240 mg, omalizumab at a dose of 300 mg, or placebo, administered subcutaneously every 4 weeks for a period of 20 weeks, or a single 120-mg dose of ligelizumab. Disease symptoms of hives, itch, and angioedema were monitored by means of weekly activity scores. The main objective was to determine a dose-response relationship for the complete control of hives (indicated by a weekly hives-severity score of 0, on a scale from 0 to 21, with higher scores indicating greater severity); the primary end point of this response was assessed at week 12. Complete symptom control was indicated by a weekly urticaria activity score of 0 (on a scale from 0 to 42, with higher scores indicating greater severity). Safety was analyzed throughout the trial.

RESULTS

A total of 382 patients underwent randomization. At week 12, a total of 30%, 51%, and 42% of the patients treated with 24 mg, 72 mg, and 240 mg, respectively, of ligelizumab had complete control of hives, as compared with 26% of the patients in the omalizumab group and no patients in the placebo group. A dose-response relationship was established. At week 12, a total of 30%, 44%, and 40% of the patients treated with 24 mg, 72 mg, and 240 mg, respectively, of ligelizumab had complete control of symptoms, as compared with 26% of the patients in the omalizumab group and no patients in the placebo group. In this small and short trial, no safety concerns regarding ligelizumab or omalizumab emerged.

CONCLUSIONS

A higher percentage of patients had complete control of symptoms of chronic spontaneous urticaria with ligelizumab therapy of 72 mg or 240 mg than with omalizumab or placebo. (Funded by Novartis Pharma; ClinicalTrials.gov number, NCT02477332.).

Investigation of Autoimmune Disease in Children with Chronic Spontaneous Urticaria

INTRODUCTION

Chronic spontaneous urticaria (CSU) in childhood affects the quality of life of the patient and may be associated with other autoimmune diseases. The aim of this study was to investigate the association of autoimmune diseases with CSU in children.

METHODS

In a 3-year period, from 2015 to 2018, forty-nine children were diagnosed with CSU and monitored in the Outpatient Pediatric Allergy Clinic of the University Hospital of Ioannina in Northwestern Greece. The comorbidity with other autoimmune diseases was investigated in this population by autoantibody evaluation.

RESULTS

Of the 49 children with CSU, 1 had autoantibodies for celiac disease (CD), which was confirmed by duodenal biopsy via gastroscopy. Four children had high serum levels of anti-thyroid peroxidase antibodies but normal thyroid function. No other specific autoantibodies were detected.

CONCLUSION

The prevalence of autoimmune diseases among our children with CSU was low. Nevertheless, we think it is important to test children with CSU for other autoimmune diseases. CD can be diagnosed in children with CSU even in the absence of other indicative signs.

Pruritus in allergy and immunology

Although evolutionarily conserved to expel ectoparasites and aid in the clearance of toxins and noxious environmental stimuli from the host, the type 2 immune response can become pathologic in the setting of a variety of allergic disorders. Itch can be a behavioral extension of type 2 immunity by evoking scratching and, in the setting of disease, can become chronic and thus highly pathologic as well. Classically, our understanding of itch mechanisms has centered around the canonical IgE-mast cell-histamine axis. However, therapies aimed at blocking the histaminergic itch pathway have been largely ineffective, suggesting the existence of nonhistaminergic itch pathways. Indeed, recent advances in itch biology have provided critical new insight into a variety of novel therapeutic avenues for chronic itch in the setting of a number of allergic disorders. Here we highlight how these new developments will likely inform the problem of pruritus in a variety of well-established and emerging conditions in the field of allergy.

Differentiation between control subjects and patients with chronic spontaneous urticaria based on the ability of anti-IgE autoantibodies (AAbs) to induce FcεRI crosslinking, as compared to anti-FcεRIα AAbs

BACKGROUND

The reported prevalences of IgG autoantibodies (AAbs) to FcεRIα and IgE in sera from patients with chronic spontaneous urticaria (CSU) have varied, and these AAbs are also often observed in healthy control subjects. Regarding the histamine release activity of purified IgG from patients with CSU, the number of examined patients has been small. Thus, we sought to determine the prevalence and FcεRI crosslinking ability of these AAbs in a large number of patients with CSU and non-atopic control (NC) subjects.

METHODS

We compared the concentrations of anti-IgE and anti-FcεRIα AAbs and the abilities of these AAbs to cause FcεRI aggregation in patients with CSU (n = 134) and NC subjects (n = 55) using ELISA and an in vitro elicitation test, respectively.

RESULTS

The concentration of anti-IgE AAbs was significantly different between the NC subjects and the CSU patients (P < 0.0001, cutoff value: 0.558 μg/mL), whereas the concentration of anti-FcεRIα AAbs was not. A significant difference in the duration of illness was noted between patients with lower and those with higher concentrations of anti-IgE AAbs relative to the cutoff value. The abilities of anti-IgE AAbs, but not anti-FcεRIα AAbs, to induce FcεRI crosslinking were significantly higher in CSU patients than in NC subjects (P = 0.0106).

CONCLUSIONS

In the Japanese population of CSU patients studied, the ability of the anti-IgE AAbs to induce FcεRI crosslinking differed significantly between NC subjects and CSU patients, suggesting the involvement of anti-IgE AAbs in the pathogenesis of CSU in the Japanese population.

Diagnosis and treatment of urticaria in primary care

Urticaria, also known as hives among people, is a very common disease characterized by erythematous, edematous, itchy, and transient plaques that involve skin and mucous membranes. It is classified as acute spontaneous urticaria, chronic spontaneous urticaria, chronic inducible urticaria, and episodic chronic urticaria. Many factors such as infections, medicines, food, psychogenic factors, and respiratory allergens are accused of etiology, but sometimes, it is idiopathic. Clinical presentation involves red, swelling, and itchy plaques. The lesions usually resolve spontaneously within 2-3 h without a trace. The patients are sometimes confronted with an angioedema that can also involve the respiratory tract. In this case mucous membranes, such as eyelids, lips, swell with some pain and burning sensation. If respiratory tracts are involved, it may be life threatening and should be treated urgently. The diagnosis is usually straightforward, urticarial vasculitis, drug eruptions, viral eruptions, and urticaria pigmentosa must also be considered. H1 antihistamines and, sometimes, short-term systemic corticosteroids are preferred for the treatment; H2 antagonists may be added during resistant cases, although other treatment options, such as omalizumab, cyclosporine, and leukotriene receptor antagonists, may be considered during missed events.

Successful Treatment With Omalizumab in a Child With Asthma and Urticaria: A Clinical Case Report

Childhood urticaria is not rare, although its persistence is less frequent. In children, chronic spontaneous urticaria (CSU) is associated with comorbidities, including asthma, allergic rhinitis, or atopic dermatitis, and many children with CSU have a family history of atopy. The therapeutic approach to CSU in children is the same one recommended by international guidelines for treatment of chronic urticaria in adults. In the European Union, according to the European Medicine Agency, omalizumab is the add-on drug of choice for the management of CSU in adult and adolescent patients (from 12 years of age) with inadequate response to H1 antihistamine therapy. In addition, in children (6 to <12 years of age), it is the add-on therapy of choice to improve asthma control. The management of children with urticaria under 12 is a therapeutic area with few certainties, where omalizumab can be administered only "off-label."

Causal Relationship Between Anti-TPO IgE and Chronic Urticaria by In Vitro and In Vivo Tests

PURPOSE

Immunoglobulin (Ig) E autoantibodies against thyroid antigens such as thyroid peroxidase (TPO) have been demonstrated in chronic spontaneous urticaria (CSU) patients in higher frequency than healthy subjects. However, if these IgE autoantibodies can trigger urticaria is still a matter of study. The aim of this study was to investigate the relationship between concomitant IgE autoantibodies against thyroid antigens in CSU.

METHODS

Patients with CSU, healthy subjects and patients with autoimmune thyroid disease (ATD) were recruited. Total IgE and specific anti-TPO IgE and IgG were assessed in all subjects. The basophil activation test and skin tests with TPO were performed to demonstrate whether this antigen could selectively induce urticaria reaction in subjects with positive anti-TPO IgE.

RESULTS

Anti-TPO IgE was present in all 3 groups (CSU: 34.0%, ATD: 16.6%, healthy subjects: 8.1%). Anti-TPO IgE levels were higher in CSU patients, whereas anti-TPO IgG were higher in ATD patients. After exposure to TPO, CD203c expression from patients with CSU and anti-TPO IgE significantly increased in comparison to the other groups; 33.0% vs. 14.0% in ATD patients and 9.0% in control subjects (P < 0.05). Skin reactions with TPO were higher in patients with CSU according to the intradermal (CSU: 18.0%, ATD: 3.3%, control: 8.0%) and skin prick tests (12.0%, 0%, 0%, respectively). Passive transfer of anti-TPO IgE from a CSU patient to the skin of control subjects without anti-TPO IgE induced a positive skin reaction.

CONCLUSIONS

Anti-TPO IgE is not a specific biomarker for CSU. However, IgE against TPO plays a pathogenic role in inducing effector cell activation and skin exacerbation in some patients with CSU.

Efficacy and safety of Xiaofeng powder (xiao feng san) in treating urticaria: A protocol for a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Urticaria is a common skin disease that has a high impact on a patient's daily life. Xiaofeng powder (XFP) is one of the most commonly used Chinese herbal formula in China for urticaria. However, due to the lack of systematic evaluations, its clinical efficacy remains controversial. This meta-analysis was performed to evaluate the effect and safety of XFP for urticaria.

METHODS

Seven databases, including Cochrane Central Register of Controlled Trials, PubMed, Embase, the Chinese National Knowledge Infrastructure (CNKI), the Chinese Scientific Journal Database (VIP), the Chinese Biomedical Literature Database (CBM), and the Wanfang Database. The period will be from their inception to September 2018. Randomized controlled trials of XFS used separately against conventional Western medicine therapy in patients with urticarial were included. After the methodologic quality was assessed and the valid data were extracted, RevMan 5.3 software was used for the final meta-analysis.

RESULTS

The results will provide evidence regarding the efficacy and safety of XFP in treating urticaria.

CONCLUSION

The conclusion of our systematic review will provide evidence to judge whether XFP is an effective intervention for patient with urticaria. This systematic review will be disseminated in peer-reviewed publications. The results of the study will provide evidence concerning the efficacy and safety of Xiaofeng Powder (xiao feng san) in treating urticaria.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD 42018087260.

The effect of omalizumab on hematological and inflammatory parameters in patients with chronic spontaneous urticaria

PURPOSE

The mechanism of action of omalizumab in chronic spontaneous urticaria (CSU) is not exactly known. In previous studies, d-dimer which is a fibrin-degradation product and interleukin-31 which has a role in inflammation were found to be decreased in patients with chronic urticaria treated with omalizumab. However, to our knowledge, there is no study on the effects of omalizumab on the ratio of neutrophil to lymphocyte (NLR) and the ratio of platelet to lymphocyte (PLR) which are inflammatory parameters in patients with CSU in the PubMed database. In this study, we aimed to evaluate the effects of omalizumab on hematological and inflammatory parameters in patients with CSU.

MATERIALS AND METHODS

One hundred six CSU patients treated with omalizumab were evaluated retrospectively. Complete blood count (CBC) and C-reactive protein (CRP) levels before treatment and at the third month of treatment were recorded. NLR and PLR were calculated from the CBC results. CBC parameters, CRP levels, NLR and PLR of the patients before treatment and at the end of third month of treatment were compared.

RESULTS

There was a significant decrease in white blood cell count, platelet count, neutrophil count, CRP level, NLR and PLR and a significant increase in mean platelet volume and eosinophil count with omalizumab treatment in CSU patients (p < 0.05). Basophil count increased; but there was no statistically significant difference (p = 0.293).

CONCLUSION

This study shows that omalizumab has not only anti Ig E effect, but also it may have inhibitory effects on inflammation and coagulation in patients with CSU. Further prospective studies are warranted in order to evaluate the effect of omalizumab on hematological and inflammatory parameters and correlation between omalizumab response rate and these inflammatory parameters in patients with CSU.

Effectiveness of omalizumab in adolescent and adult patients with chronic idiopathic/spontaneous urticaria: a systematic review of 'real-world' evidence

INTRODUCTION

Chronic idiopathic/spontaneous urticaria (CIU/CSU) is a dermatological condition characterized by itchy wheals and/or angioedema of continuous or intermittent duration of ≥6 weeks with a high burden of disease and impact on quality of life. Omalizumab is a recombinant humanized monoclonal antibody that inhibits the binding of IgE to high affinity receptors, and is approved for the CIU/CSU indication. The objective of this systematic review was to evaluate and synthesize the evidence on the real-world effectiveness of omalizumab in CIU/CSU in daily clinical practice.

AREAS COVERED

This review of 84 observational effectiveness studies covers treatments (dosing, medication use), clinical outcomes (treatment response, disease activity, quality of life), and safety.

EXPERT OPINION

The clinical outcomes observed across studies underscore the real-world effectiveness of omalizumab in the management of CIU/CSU. Continued treatment may assist patients showing an initial response to achieve a complete treatment response. Response rates are aligned with observed changes in disease activity, symptom experience, and quality of life, and this across subtypes of CIU/CSU. The positive therapeutic profile is complemented by a positive safety profile. The real-world evidence summarized here points convincingly at the high degree of effectiveness of omalizumab in the treatment of CIU/CSU in daily clinical practice.

Clinical Course of Chronic Spontaneous Urticaria in the Korean Adult Population

Knowledge of the clinical course of chronic spontaneous urticaria (CSU) remains unclear. The purpose of our study was to investigate the clinical course of CSU in the Korean adult population. Each patient in the CSU group who was defined by disease codes between 2003 and 2007 was tracked whether he or she went into remission or not until 2013. Kaplan-Meier survival analysis was carried out to analyze remission, and log-rank tests were performed for between-group comparisons. Demographic differences between subjects who went into remission 1 year after the initial diagnosis and those who did not were analyzed using χ² tests. A total of 13,969 subjects were included in the CSU group. The 1-, 2-, 3-, 4-, and 5-year remission rates of CSU were 21.5%, 33.0%, 38.9%, 42.6%, and 44.6%, respectively. The proportion of subjects in the 65+ age group (P=0.050) and with male gender (P=0.002) was significantly higher among subjects who did not go into remission 1 year after the initial diagnosis. Our study indicates that CSU could have a more persistent course than previously reported.