Serum IgE as an immunological marker to predict response to omalizumab treatment in symptomatic chronic urticaria

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.

Total IgE as a biomarker of omalizumab response in chronic spontaneous urticaria: A meta-analysis

Background: Omalizumab is approved for the treatment of chronic spontaneous urticaria (CSU) that is refractory to antihistamines. Total immunoglobulin E (IgE) levels have emerged as a possible biomarker to predict response to omalizumab. However, the existing literature is heterogenous, with conflicting conclusions with regard to the role of total IgE levels. Objective: We sought to clarify the role of evaluating total IgE levels in patients with CSU by performing a meta-analysis on the existing literature to determine if meaningful changes exist between responders and nonresponders to omalizumab. Methods: A total of 68 unique citations were returned and screened by two independent reviewers. Editorials, reviews, and case reports were excluded, and a total of 33 original articles were identified and underwent secondary evaluation. Studies that present mean ± standard deviation total IgE levels and/or 95% confidence intervals (CI) were included, whereas studies with < 25 subjects were excluded. Three studies ultimately met these criteria. Results: We found a mean difference in total IgE levels between those who responded to omalizumab versus those without a response of 49.76 (95% CI, 7.13-92.38; p = 0.02), which demonstrated higher mean IgE values in responders compared with nonresponders. Conclusion: This study presents additional evidence that supports evaluation of total IgE levels as it pertains to response to omalizumab therapy in CSU. When considering the current evidence, it seems reasonable to consider the baseline total IgE level as a biomarker to predict the treatment response to omalizumab. Based on the existing literature, we cannot conclude at what threshold nonresponse is more likely to occur.

Type I and type IIb autoimmune chronic spontaneous urticaria: Using common clinical tools for endotyping patients with CSU

Background

Mechanisms triggering the pathogenesis of chronic spontaneous urticaria (CSU) have been identified as type I autoallergic (which is associated with IgE antibodies against autoantigens) and type IIb autoimmune (which is driven by autoantibodies to FceR1 and/or IgE).

Objective

Our aim was to define presumptive endotypes in patients with CSU by using tests amenable to use in routine clinical practice.

Methods

A retrospective analysis of the medical records of 394 patients with CSU with or without chronic inducible urticaria or angioedema was performed. Patients were assigned to 1 of 4 groups as follows: (1) type I endotype of CSU, if they presented at least 1 of the following: allergic disease, total IgE level of at least 40UI/mL, and positive result of skin tests to inhalant allergen(s), (2) type IIb endotype of CSU, if they presented at least 1 of following: autoimmune disease, low total IgE level less than 40 IU/mL, positive autologous serum skin test result, positive for antinuclear antibodies in a titer of at least 1:160, and elevated level of anti-thyroid peroxidase, (3) overlap of type I/type IIb endotypes of CSU, if they presented with at least 1 marker of both type I and type IIb, and (4) non-type I/type IIb endotype of CSU, if they presented with none of the markers of type I or type IIb.

Results

The mean age at onset of symptoms was 34 years; 82.2% of those with CSU were female, and angioedema and chronic inducible urticaria were found in 74.8% and 31.9% of patients, respectively. Of the patients with CSU, 38% presented with the type I endotype and 51% presented with type I/type IIb overlap, whereas 9% presented with the type IIb endotype and 2% presented with the non-type I/type IIb endotype. Eosinopenia was associated with type IIb and type I/type IIb overlap as opposed to the type I and non-type I/type IIb endotypes (P = .02).

Conclusions

Most patients with CSU presented with features of the type 1 (autoallergic) endotype, whether associated with type IIb (autoimmune) endotype or not.

Omalizumab for Patients with Chronic Spontaneous Urticaria: A Narrative Review of Current Status

Chronic spontaneous urticaria (CSU) is a debilitating inflammatory disorder of the skin, characterized by a fluctuating natural history, a complex mechanism of action, and a significant burden on patients, including effect on quality of life, development of psychosocial disorders, and a range of comorbidities. Recent international guidelines recommend a therapeutic approach of first-line treatment with second generation H1-antihistamines and second-line treatment with the biologic omalizumab. Here, the salient aspects of CSU and current status of data for omalizumab for patients with CSU are reviewed, with a focus on mechanism of action, efficacy and real-world effectiveness (including patient outcomes, response, relapse, and remission), and safety (including consideration of the risk of anaphylaxis). The review also considers recent data on COVID-19, CSU, and omalizumab and presents our perspective on future needs. Overall, the data suggest that omalizumab is an effective and well-tolerated treatment for patients with CSU that provides benefits for a wide range of patients.

Chronic Spontaneous Urticaria: The Role and Relevance of Autoreactivity, Autoimmunity, and Autoallergy

Chronic spontaneous urticaria (CSU) is a frequent and often severely disabling disease. A large number of studies were performed during the last 2 decades to clarify its pathogenesis. These studies shed light on the underlying autoimmune mechanisms of CSU pathogenesis and have led us to understand that different mechanisms may exist and, sometimes, coexist behind the same clinical presentation. The present article reviews the meaning of the terms autoreactivity, autoimmunity, and autoallergy, which have been variably used over the years to define different endotypes of the disease. Furthermore, we discuss the methods potentially able to lead us to the correct classification of CSU patients.

Biomarkers for Monitoring Treatment Response of Omalizumab in Patients with Chronic Urticaria

Chronic urticaria (CU) is a debilitating skin disease affecting around 1% of the population. CU can be subdivided into chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIndU). Different pathophysiological mechanisms have been proposed to play a role in the development of CU, and these are also being investigated as potential biomarkers in the diagnosis and management of the disease. As of now the only assessment tools available for treatment response are patient reported outcomes (PROs). Although these tools are both validated and widely used, they leave a desire for more objective measurements. A biomarker is a broad subcategory of observations that can be used as an accurate, reproducible, and objective indicator of clinically relevant outcomes. This could be normal biological or pathogenic processes, or a response to an intervention or exposure, e.g., treatment response. Herein we provide an overview of biomarkers for CU, with a focus on prognostic biomarkers for treatment response to omalizumab, thereby potentially aiding physicians in personalizing treatments.

Omalizumab prevents respiratory illnesses in non-atopic chronic spontaneous urticaria patients: A prospective, parallel-group, pilot pragmatic trial

BACKGROUND

Omalizumab is the recommended treatment for antihistamine-refractory chronic spontaneous urticaria (CSU) and severe allergic asthma. In addition, it has been shown to reduce the frequency of viral respiratory infections in allergic asthma. Respiratory illness is a known trigger for asthma and CSU.

OBJECTIVES

To explore whether the antiviral effect of omalizumab may be extended to CSU patients independent of their atopic status.

METHODS

We conducted a prospective parallel-group pilot pragmatic trial including 30 non-allergic and non-atopic CSU patients (cases) under omalizumab 300 mg Q4-weeks (due to refractory to H1-antihistamines) and 30 age-matched healthy controls. All CSU patients had to have a weekly urticaria activity score UAS7 <15 at least 4 weeks before recruitment. Using the self-filled validated Jackson scale, we evaluated all study participants for common cold symptoms. All cases and controls rated weekly their respiratory symptoms. An increase in the symptom score of at least 4 points compared to baseline (defined as the minimum weekly report of symptoms) was considered an episode suggestive of a viral infection of the upper respiratory tract (URT). The patients were follow-up every 4 weeks throughout the study period (10 months).

RESULTS

CSU patients under omalizumab reported fewer episodes suggestive of an URT viral infection than the healthy controls (median of reported episodes: 0 vs. 1, inter-quartile range 0-1 vs. 1-1, min-max: 0-3 vs. 0-4, respectively; p = 0.0095). The duration of each episode was the same in both cases and controls.

CONCLUSIONS

Omalizumab can reduce the number of common cold episodes in CSU patients and consequently may minimize viral-related CSU exacerbations. This beneficial effect is exerted independently of the atopic status, even in non-asthmatic individuals or non-allergic patients without any evidence of respiratory susceptibility. Further large-scale studies are needed to validate the current findings and elucidate the underlying relevant pathophysiology.

Urticaria and basophils

Chronic spontaneous urticaria (CSU) is a common skin disease without an etiology in the vast majority of cases. The similarity of symptoms and pathology to allergen-induced skin reactions supports that skin mast cell IgE receptor activation is also involved in CSU. Accumulating evidence also supports a role for blood basophils in disease expression. Blood basopenia is noted in active CSU disease with the recruitment of blood basophils to skin lesion sites. Blood basophils further display altered IgE receptor mediated degranulation patterns in two phenotypes that improve in remission. In active CSU subjects, changes in IgE receptor signaling molecule expression levels accompany the altered degranulation function in blood basophils. The success of therapies targeting IgE in CSU patients have also shown that altered blood basophil phenotypes and enumeration have potential use as a disease biomarker.

Thyroid Autoimmunity in CSU: A Potential Marker of Omalizumab Response?

The response of severe chronic spontaneous urticaria (CSU) to omalizumab largely depends on the autoimmune or autoallergic endotype of the disease. Whether thyroid autoimmunity may predict omalizumab response along with total IgE in CSU is still unclear. Three hundred and eighty-five patients (M/F 123/262; mean age 49.5 years; range 12-87 years) with severe CSU were studied. Total IgE levels and thyroid autoimmunity (levels of anti-thyroid peroxidase [TPO] IgG) were measured before omalizumab treatment. Based on the clinical response, patients were divided into early (ER), late (LR), partial (PR) and non (NR) responders to omalizumab. Thyroid autoimmunity was detected in 92/385 (24%) patients. Altogether, 52%, 22%, 16% and 10% of patients were ER, LR, PR and NR to omalizumab, respectively. Response to omalizumab was not associated with thyroid autoimmunity (p = 0.77). Conversely, we found a strongly positive association between IgE levels and omalizumab response (p < 0.0001); this association was largely driven by early response (OR = 5.46; 95% CI: 2.23-13.3). Moreover, the predicted probabilities of early response strongly increased with increasing IgE levels. Thyroid autoimmunity alone cannot be used as a clinical predictor of omalizumab response. Total IgE levels remain the only and most reliable prognostic marker for omalizumab response in patients with severe CSU.

Management of Allergic Skin Disorders in Pregnancy

The safe management of allergic skin disorders during pregnancy is essential to maternal and fetal health. Poorly controlled allergic skin disease affects the health of mother and child. This article reviews the disease course and treatment of atopic dermatitis, chronic urticaria, and allergic contact dermatitis in pregnancy. It focuses on topical and systemic therapies in the context of pregnancy and breastfeeding. Because disease activity may vary in pregnancy, prescription stewardship is imperative; a balance among disease control, minimum effective dosing, and medication safety profiles should be maintained. Secondary complications and risks to maternal or infant health should also be avoided.

Prospective, monocentric, observational study of the long-term effectiveness of omalizumab in chronic urticaria

Omalizumab, a monoclonal antibody targeting IgE, has been approved in 2014 for the treatment of H1 antihistamine-refractory chronic urticaria. Data on long-term effectiveness and predictive factors for treatment response are currently limited. In this monocentric, prospective, observational study, 112 patients with chronic spontaneous urticaria (CSU) and 32 patients with chronic inducible urticaria (CIndU) were included. In addition to a rapid response, omalizumab also showed good effectiveness on both forms of chronic urticaria over 2 years. Low total IgE and elevated Yersinia IgA were identified as potential predictive markers for slower treatment responses in CSU. In conclusion, the present study highlights the efficacy of omalizumab for the treatment of chronic urticaria. With emerging new therapeutic options for chronic urticaria, further genetic as well as molecular markers are needed to establish patient-specific therapy selection.

Current and future management of chronic spontaneous urticaria and chronic inducible urticaria

Background: Chronic urticaria (CU), characterized by ≥6 weeks of intense pruritus, remains a debilitating condition for patients. New and safe treatments are needed to manage CU recalcitrant to standard therapy. Objective: A review of the current literature of standard and novel therapeutics in the management of CU was conducted. Methods: A literature search via a medical literature data base and clinical trial data base was conducted to identify treatment options for CU and current clinical trials. Results: Second-generation antihistamines, omalizumab, and cyclosporine remain the most proven therapeutic options for CU. Dupilumab, mepolizumab, benralizumab, tezepelumab, and CDX-0159 are all undergoing clinical trials for CU. Although ligelizumab demonstrated initial promising results, a phase III study was discontinued due to a nonsuperior clinical impact compared with omalizumab. Conclusion: Novel therapies are needed for the treatment of recalcitrant CU. With a deeper understanding of the pathophysiology of CU, promising therapeutics are in clinical trials for CU.

Biologicals in Treatment of Chronic Urticaria: A Narrative Review

Chronic urticaria is a common inflammatory skin disease affecting around 0.5-1% of the world's population. The disease has a chronic indolent course which significantly affects the patient's quality of life. Urticaria pathogenesis involves cross-linking of immunoglobulin E (IgE) on mast cells causing degranulation which occurs by various pathways which leads to development of wheals and angioedema. The first-line treatment for chronic urticaria is non-sedating second-generation H1 antihistamines (AHs). After the advent of anti-IgE monoclonal antibody omalizumab, the response rate in resistant urticaria has improved significantly without any major adverse events. Other biologicals such as anti-IgE, anti-IL-5, anti-IL-1, anti-IL-17, and anti-CD20 monoclonal antibodies are under trial. These biologicals have better efficacy and safety profile as compared to conventional immunosuppressants. Even with the advances in the last decade, recurrence after stopping the therapy is common, and there is a need for better understanding of the pathogenesis and the drugs acting on the key pathways involved in urticaria. In this review, we provide the role of several biologicals in the treatment of chronic urticaria.

Biologics for chronic spontaneous urticaria: toward a personalized treatment

INTRODUCTION

Chronic spontaneous urticaria (CSU) is characterized by the recurrent occurrence of short-lived wheals with or without angioedema for more than 6 weeks. Although its pathogenesis is not completely defined, several mechanisms seem involved, including autoimmunity and autoallergy with complement and coagulation activation. Various biologics are currently available or under investigation to counteract different CSU pathomechanisms.

AREAS COVERED

The recent literature dealing with biologics in the treatment of CSU was screened and analyzed; the different treatments were divided into anti-IgE and other than anti-IgE biologics. The latter were subdivided according to their target mechanisms.

EXPERT OPINION

Biologic drugs exert their effects in a very precise and specific manner. A majority of patients (arguably those with type I disease) respond to anti-IgE treatment. Others, possibly with type IIa disease, show a slow response to anti-IgE drugs. Things are much more complicated in anti-IgE-refractory patients. Some respond well to nonspecific immune suppressors, such as corticosteroids and cyclosporin suggesting that an immune-mediated pathogenic mechanism, not involving the high-affinity IgE receptor, is probably active. Several ongoing studies are evaluating biologics and small molecules counteracting other pathomechanisms, including anti-receptor biologics, Bruton tyrosine kinase (BTK) inhibitors, mast cell targets, and specific cytokines.

Real-world safety and effectiveness of omalizumab in Japanese patients with chronic spontaneous urticaria: A post-marketing surveillance study

BACKGROUND

The safety and efficacy of omalizumab in chronic spontaneous urticaria (CSU) patients has been established, but real-world long-term data remain scarce, especially in Japan.

METHODS

52-week, open-label, single-arm, observational study evaluated the safety and effectiveness of first-time omalizumab in Japanese CSU patients responding inadequately to conventional therapies.

RESULTS

Overall, 235 of 280 patients completed the study. Most patients were aged ≥ 18 and < 65 years; adolescents (≥ 12 and ≤ 18 years) accounted for 9.6% of the total population. The mean ± standard deviation (SD) duration of CSU at baseline was 1.6 ± 3.1 years; 46.1% of patients had had CSU for < 6 months. At baseline, the mean ± SD of Urticaria Control Test (UCT) score, Weekly Urticaria Activity Score (UAS7), and Dermatology Life Quality Index (DLQI) were 5.1 ± 3.2, 25.2 ± 11.9, and 8.4 ± 5.9, respectively. The mean ± SD duration of the observation period was 330.3 ± 86.2 days. Relapse was reported in 65 patients, 51, 9, and 5 of whom required retreatment with omalizumab 1, 2, and ≥ 3 times, respectively. The incidence of adverse events (AEs), serious AEs, and adverse drug reactions (ADRs) was reported in 11.8%, 1.4%, and 3.9% of patients, respectively. The most common AEs were urticaria (1.8%) and eczema (1.1%). No adolescents experienced ADRs. A cumulative of 92.8% of patients responded in the Physician's Global Impression of Change, with 81.3%, 75.0%, and 95.1% of patients achieving UCT ≥ 12, UAS7 ≤ 6, and DLQI ≤ 5 up to Week 52, respectively.

CONCLUSIONS

This study supports the safety and effectiveness of omalizumab in CSU patients who responded inadequately to conventional therapies in real-world clinical practice in Japan.

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.

Urticaria in Pregnancy and Lactation

Chronic urticaria (CU) is a mast cell-driven chronic inflammatory disease with a female predominance. Since CU affects mostly females in reproductive age, pregnancy is an important aspect to consider in the context of this disease. Sex hormones affect mast cell (MC) biology, and the hormonal changes that come with pregnancy can modulate the course of chronic inflammatory conditions, and they often do. Also, pregnancy-associated changes in the immune system, including local adaptation of innate and adaptive immune responses and skewing of adaptive immunity toward a Th2/Treg profile have been linked to changes in the course of inflammatory diseases. As of now, little is known about the effects of pregnancy on CU and the outcomes of pregnancy in CU patients. Also, there are no real-life studies to show the safety of urticaria medications during pregnancy. The recent PREG-CU study provided the first insights on this and showed that CU improves during pregnancy in half of the patients, whereas it worsens in one-third; and two of five CU patients experience flare-ups of their CU during pregnancy. The international EAACI/GA2LEN/EuroGuiDerm/APAAACI guideline for urticaria recommends adopting the same management strategy in pregnant and lactating CU patients; starting treatment with standard doses of second-generation (non-sedative) H1 antihistamines, to increase the dose up to 4-folds in case of no response, and to add omalizumab in antihistamine-refractory patients; but also emphasizes the lack of evidence-based information on the safety and efficacy of urticaria treatments during pregnancy. The PREG-CU study assessed treatments and their outcomes during pregnancy. Here, we review the reported effects of sex hormones and pregnancy-specific immunological changes on urticaria, we discuss the impact of pregnancy on urticaria, and we provide information and guidance on the management of urticaria during pregnancy and lactation.

Omalizumab for the Treatment of Bullous Pemphigoid: A Systematic Review of Efficacy and Safety

Bullous pemphigoid (BP) is an autoimmune blistering skin disease. Current treatment strategies are limited by their efficacy and/or side effect profile and the need for safer and effective alternatives is undeniable. We aimed to conduct a systematic review focusing on the efficacy and safety of omalizumab in BP patients. Embase, PubMed, Cochrane, and clinicaltrials.gov were searched for English and French articles published from inception to July 1, 2021, using search terms "omalizumab" OR "Xolair" OR "IGE025" OR "olizumab" AND "bullous pemphigoid." Screening and data extraction was performed by two raters independently. The primary outcome was complete response (CR), and secondary outcomes were partial response (PR), flare-ups, adverse events/vital status. In total, 22 articles were included, with a total of 56 patients. All patients had a refractory BP with mean disease duration of 13.5 ± 20.2 months (Standard Deviation (SD)) and failed 3.1 ± 1.6 therapies and many remained corticosteroids dependent. Overall, 87.5% of patients responded to treatment (55.4% CR and 32.1% PR), 7.1% discontinued the protocol and only 5.4% were non responders. A third of patients were able to discontinue all other therapies and most others were able to discontinue or taper systemic corticosteroids to <10 mg daily. Flare-ups occurred in 57.7% of patients upon discontinuation of omalizumab and/or steroid tapering, most patients recaptured response thereafter. Omalizumab was well tolerated by most patients. Omalizumab appears to be a promising treatment for BP with a good response rate and safety profile. However, several limitations were identified in current literature, and highlight the need for randomized controlled trials of omalizumab in BP.

Effects of pregnancy on chronic urticaria: Results of the PREG-CU UCARE study

BACKGROUND

Chronic urticaria (CU) predominantly affects women, and sex hormones can modulate disease activity in female CU patients. As of now, the impact of pregnancy on CU is largely unknown.

AIM

To analyze the course and features of CU during and after pregnancy.

PATIENTS AND METHODS

PREG-CU is an international, multicenter study of the Urticaria Centers of Reference and Excellence (UCARE) network. Data were collected via a 47-item questionnaire completed by CU patients, who became pregnant within the last 3 years.

RESULTS

A total of 288 pregnancies of 288 CU patients from 13 countries were analyzed (mean age at pregnancy: 32.1 ± 6.1 years, duration of CU: 84.9 ± 74.5 months; CSU 66.9%, CSU + CIndU 20.3%, CIndU 12.8%).During pregnancy, 51.1% of patients rated their CU as improved, 28.9% as worse, and 20.0% as unchanged.CU exacerbations most commonly occurred exclusively during the third trimester (in 34 of 124 patients; 27.6%) or the first (28 of 124; 22.8%). The risk factors for worsening of CU during pregnancy were having mild disease and no angioedema before pregnancy, not taking treatment before pregnancy, CIndU, CU worsening during a previous pregnancy, treatment during pregnancy, and stress as a driver of exacerbations. After giving birth, urticaria disease activity remained unchanged in 43.8% of CU patients, whereas 37.4% and 18.1% experienced worsening and improvement, respectively.

CONCLUSIONS

These results demonstrate the complex impact of pregnancy on the course of CU and help to better counsel patients who want to become pregnant and to manage CU during pregnancy.

Predictors of treatment response in chronic spontaneous urticaria

The current therapeutic algorithm for chronic spontaneous urticaria (CSU), endorsed by the international guideline, entails treatment escalation from second-generation H₁ -antihistamines (sgAHs) to omalizumab and cyclosporine until complete response is achieved. Recently, several predictors of response to these treatment options have been described. Here, we discuss the most promising predictors of response and nonresponse to these treatments in CSU. A systematic search was performed by two independent researchers using the MEDLINE/PubMed database with specific keywords and 73 studies included in the review. Levels of evidence were categorized as strong (robust predictors), weak (emerging predictors) or no association, based on the outcome and number of studies available. High disease activity, high levels of C-reactive protein and D-dimer are robust predictors for a poor or no response to sgAHs. Poor or no response to omalizumab is robustly predicted by low serum levels of total IgE. A good response to cyclosporine is robustly predicted by a positive basophil histamine release assay, whereas low total IgE is an emerging predictor. The response to treatment with sgAHs, omalizumab and cyclosporine can be predicted by the use of markers that are readily available in routine clinical practice. Further studies are needed to confirm these predictors.

Long term treatment with omalizumab in adolescent with refractory solar urticaria

BACKGROUND

Solar urticaria represents an uncomfortable form of chronic inducible urticaria. First and second-line treatments are ineffective in some patients, leading to an impairment in their quality of life. Omalizumab represents a safe therapeutic option in case of refractory solar urticaria.

CASE PRESENTATION

We update a case of a 21-year-old Caucasian girl affected by solar urticaria from the age of 14. Poor disease control was achieved with standard or high-dose of H₁-antihistamines. Several omalizumab courses, including a 1-year-long course, were practiced resulting in clinical remission and significant improvement in patient's quality of life.

CONCLUSION

Our experience confirms the effectiveness and safety of omalizumab for the management of refractory solar urticaria. Future studies are awaited in order to monitor long term effects and chronic doses of this treatment, particularly in patients who need concomitant therapy with antihistamines.

Roles of IgE and Histamine in Mast Cell Maturation

Mast cells are activated upon immunoglobulin E (IgE)-mediated antigen stimulation, and release a wide variety of mediators, including histamine to trigger inflammatory responses. The surface expression levels of Fcε receptor I (FcεRI), a high affinity receptor of IgE, were found to be positively regulated by IgE. IgE could protect murine cultured mast cells from apoptotic cell death induced by the deprivation of interleukin-3 and a certain kind of IgE could activate immature mast cells in the absence of antigens, leading to the release of pro-inflammatory cytokines and a transient increase in histamine synthesis. Histamine synthesis in mast cells was found to be required for the maturation of murine connective tissue-type mast cells, raising the possibility that IgE indirectly modulates local mast cell maturation. Although it remains controversial to what extent this concept of "monomeric IgE effects" could have relevance in the modulation of human mast cell functions, the therapeutic effects of anti-IgE antibodies might be accounted for in terms of the decreased serum IgE concentrations. Because drastic increases in serum IgE concentrations are often observed in patients with atopic dermatitis and chronic urticaria, a close investigation of the roles of IgE in mast cell maturation should contribute to development of novel therapeutic approaches for these inflammatory diseases.

The efficacy of omalizumab treatment in chronic spontaneous urticaria is associated with basophil phenotypes

BACKGROUND

The mechanisms underlying disease pathogenesis in chronic spontaneous urticaria (CSU) and improvement with omalizumab are incompletely understood.

OBJECTIVES

This study sought to examine whether the rate of clinical remission is concordant with baseline basophil features or the rate of change of IgE-dependent functions of basophils and/or plasmacytoid dendritic cells during omalizumab therapy.

METHODS

Adults (n = 18) with refractory CSU were treated with omalizumab 300 mg monthly for 90 days. Subjects recorded daily urticaria activity scores, and clinical assessments with blood sampling occurred at baseline and on days 1, 3, 6, 10, 20, 30, 60, and 90 following omalizumab. At baseline, subjects were categorized by basophil functional phenotypes, determined by in vitro histamine release (HR) responses to anti-IgE antibody, as CSU-responder (CSU-R) or CSU-non-responder (CSU-NR), as well as basopenic (B) or nonbasopenic (NB).

RESULTS

CSU-R/NB subjects demonstrated the most rapid and complete symptom improvement. By day 6, CSU-R/NB and CSU-NR/NB had increased anti-IgE-mediated basophil HR relative to baseline, and these shifts did not correlate with symptom improvement. In contrast, CSU-NR/B basophil HR did not change during therapy. The kinetics of the decrease in surface IgE/FcεRI was similar in all 3 phenotypic groups and independent of the timing of the clinical response. Likewise, plasmacytoid dendritic cells' surface IgE/FcεRI decline and TLR9-induced IFN-α responses did not reflect clinical change.

CONCLUSIONS

Changes in basophil IgE-based HR, surface IgE, or FcεRI bear no relationship to the kinetics in the change in clinical symptoms. Baseline basophil count and basophil functional phenotype, as determined by HR, may be predictive of responsiveness to omalizumab.

The Diagnostic Workup in Chronic Spontaneous Urticaria-What to Test and Why

BACKGROUND

In chronic spontaneous urticaria (CSU), the guidelines recommend very limited diagnostic procedures during the routine workup, although additional investigations might be indicated in some patients with CSU. For physicians treating patients with CSU, it is often difficult to decide which diagnostic tests are useful.

OBJECTIVE

To provide recommendations on what diagnostic tests should be performed on which patients with CSU.

METHODS

We performed an extensive literature search on the respective topics and identified relevant questions that should prompt diagnostic procedures based on the published evidence and expert consensus among all authors.

RESULTS

We provide questions, diagnostic testing, where appropriate, and recommendation that should be included when assessing the history of a patient with CSU, to explore and rule out differential diagnoses, to assess patients for underlying causes and modifying conditions, to explore patients for comorbid diseases and consequences of having CSU, and to assess patients for CSU components that can help to predict their disease course and response to treatment.

CONCLUSIONS

Here, we provide physicians treating patients with CSU with information about which clues should lead to which tests and why.

Non-IgE-mediated anaphylaxis

Anaphylaxis is a rapidly evolving, acute, life-threatening reaction that occurs rapidly on contact with a trigger. Anaphylaxis is classically defined as an allergen-driven process that induces specific IgE and the activation of mast cells and basophils through the cross-linking of IgE receptors. However, it is clear that non-IgE-mediated pathways can induce symptoms indistinguishable from those of classic anaphylaxis, and their activation could explain the severity of IgE-mediated anaphylaxis. Indeed, mast cells and basophils can be activated by antibodies against IgE or their receptors, by molecules such as anaphylatoxins, or through G-coupled receptors. Some other allergens can induce antibodies of class IgG that can activate neutrophils to produce a molecule similar to histamine to induce anaphylaxis. Finally, some inflammatory mediators such as bradykinin or prostaglandin can also modulate mast cell and basophil activation as well as directly cause vasodilation and bronchoconstriction, resulting in anaphylaxis-like reactions.

Anti-IgE for the Treatment of Chronic Urticaria

Urticaria and angioedema are very common. Management of chronic urticaria subtypes, which usually persist for many years, is challenging. Recent years have demonstrated that targeting IgE with antibodies provides a safe and efficient treatment approach. Whilst several anti-IgE antibodies have been developed, omalizumab is currently the only one approved for use. International and national guidelines recommend its use after failure of antihistamines at standard and increased dose. Whilst not yet approved, many new anti-IgE approaches are currently being investigated in pre-clinical studies or clinical trials. This non-systematic focused review summarizes current knowledge of omalizumab and other anti-IgE biologics in chronic urticaria using data extracted from PubMed, Google Scholar and clinical trial databases, clinicaltrials.gov and clinicaltrials.eu. For adults, there is good evidence from randomized clinical trials and real-world data that symptomatic treatment with omalizumab is efficacious and safe in chronic spontaneous urticaria (CSU), whereas evidence in chronic inducible urticaria (CINDU) and special populations is limited. Easy-to-use tools to identify non-responders and predict the required duration of treatment have not been established yet. Phase 2 b results of ligelizumab have not only demonstrated efficacy and safety but also superiority to omalizumab. Indeed, there is preliminary evidence that omalizumab non- or partial responders benefit from ligelizumab. Whereas further development of quilizumab was discontinued, other approaches, eg UB-221 or DARPins are under investigation. Anti-IgE treatment with omalizumab represents a landmark in the treatment of chronic urticaria, with and without angioedema, and there is light on the horizon suggesting success may come with various next-generation anti-IgE approaches.

Biomarkers of chronic spontaneous urticaria and their clinical implications

Introduction: Chronic spontaneous urticaria (CSU) is a frequent disorder in which activation of effector cells and histamine release can be induced via several distinct pathogenetic mechanisms. Much work has been carried out to identify biomarkers useful for classifying CSU patients, and to predict their response to currently available treatments.Areas covered: The recent literature dealing with CSU biomarkers was screened in PubMed and Google Scholar using 'chronic spontaneous urticaria', 'biomarker', 'diagnosis', 'therapy' and 'treatment response' as key words. The characteristics found in relevant papers were divided into clinical and serological biomarkers of (a) clinical severity/disease activity, and (b) response to treatments.Expert opinion: A diagnostic biomarker for CSU is still missing. Most biomarkers described so far do not seem to possess sufficient specificity for this disease. Basopenia and the activation of the coagulation cascade might be biomarkers of disease activity and severity, but information available so far is insufficient to consider their routine use. Markers suggesting IgG-mediated autoimmunity (autologous serum skin test, basophil activation/histamine release assays, low total IgE) seem to identify patients less prone to respond to omalizumab but responsive to cyclosporine. In contrast, 'autoallergy' (i.e. the presence of IgE to autoallergens), which is often associated with elevated IgE levels seems to identify patients who will respond to omalizumab.

Total IgE as a Marker for Chronic Spontaneous Urticaria

OBJECTIVE

Immunoglobulin E (IgE) and its receptor, FcɛRI, importantly contribute to the pathophysiology of chronic spontaneous urticaria (CSU). Recent findings point to a possible role of total IgE as a marker of CSU disease activity, endotypes, and responses to treatment. The evidence in support of total IgE included in the diagnostic workup of patients with CSU has not yet been reviewed.

METHODS

Publications were searched via PubMed. The search terms used were "chronic urticaria" and "total IgE." Studies were screened by titles and abstracts, and 141 were used in the review.

RESULTS

CSU patients frequently had elevated total IgE serum levels (up to 50%), but normal or very low total IgE levels also occurred. High total IgE may represent high disease activity, longer disease duration, high chance of responding to omalizumab treatment, quick relapse after stopping omalizumab, and lower chance of responding to cyclosporine. Low IgE, in contrast, may suggest Type IIb autoimmune CSU, poor response to treatment with omalizumab and a better chance to benefits from cyclosporine treatment. Furthermore, IgE in different CSU cohorts may have different physicochemical properties that could explain differences in treatment responses to IgE-directed therapies.

CONCLUSION

The results of our review suggest that total IgE is a valuable marker for CSU, and we recommend its assessment in the routine diagnostic workup of CSU patients.

Anxiety, depression, and stress in Korean patients with chronic urticaria

BACKGROUND/AIMS

Emotional distress is thought to cause or maintain chronic urticaria (CU). We aimed to investigate the presence of anxiety, depression, and stress in Korean adult CU patients and to explore their potential impact on treatment.

METHODS

We enrolled 79 CU patients and a disease control group comprising 39 persistent asthma patients. The Hospital Anxiety and Depression Scale (HADS) was used to evaluate depression and anxiety. Stress and quality of life (QoL) were assessed by Stress Response Inventory and CU-QoL questionnaires. The sociodemographic and clinical data such as urticaria activity score (UAS-15, UAS-6) were obtained.

RESULTS

The prevalence of depression and anxiety based on the HADS were 48.1% and 38.0%. Although the prevalence of anxiety didn't differ between the CU and asthma patients, depression was significantly more prevalent in the CU patients (48.1% vs. 28.2%). Stress tended to be lower in CU patients. Anxiety, depression, and stress exhibited negative correlations with QoL. Anxiety showed significant correlation with UAS-6 and pruritus-visual analog scale (VAS; r = 0.256, r = 0.272, p < 0.05, respectively); depression correlated with sleep difficulty-VAS (r = 0.261, p < 0.05). Stress was associated with UAS-15, UAS-6, pruritus-VAS, and sleep difficulty-VAS (r = 0.251, r = 0.317, r = 0.302, r = 0.258, p < 0.05, respectively).

CONCLUSION

The current study first presented that Korean CU patients frequently have anxiety and depression, which affect their QoL and demonstrated that anxiety, depression, and stress had different effects on sleep difficulty, pruritus, and urticaria severity in Korean CU patients.

Current and Potential Biologic Drugs for the Treatment of Chronic Urticaria

This article reviews biologic treatments that are currently applied for the treatment of severe chronic urticaria. Monoclonal anti-immunoglobulin E (omalizumab) is effective and safe in many patients, but accessibility and cost constitute barriers to its wider use. Questions on the optimal duration of the treatment and possible symptom recurrences after discontinuing the drug are still raised. A discussion is presented about several other biologics currently under investigation with potential to be incorporated in the near future in patients with severe chronic urticaria.

Improved FcεRI-Mediated CD203c Basophil Responsiveness Reflects Rapid Responses to Omalizumab in Chronic Spontaneous Urticaria

BACKGROUND

Omalizumab is effective in patients with chronic spontaneous urticaria (CSU) although its mechanism of action is poorly understood. Several studies reported that decreased high-affinity IgE receptor (FcεRI)-mediated histamine release and/or responsiveness was characteristic of basophils in patients with CSU. However, few studies have focused on the relationship between changes in basophil responsiveness via FcεRI after omalizumab treatment and the therapeutic effect in patients with CSU.

OBJECTIVE

To assess basophil responsiveness via FcεRI stimulation, as well as FcεRI expression and IgE binding on blood basophils from patients with CSU before and after omalizumab treatment and its possible association with the clinical response.

METHODS

We analyzed 34 patients with CSU treated with omalizumab who were categorized as fast responders (FRs) (n = 20) and non or slow responders (N/SRs) (n = 14). CD203c expression induced by FcεRI stimulation, and IgE and FcεRI expressions on blood basophils from patients with CSU before and after omalizumab treatment were analyzed. Basophil responsiveness via FcεRI stimulation was observed in vitro using basophils pretreated with omalizumab.

RESULTS

FRs had increased CD203c responsiveness after treatment with omalizumab compared with N/SRs. This improvement of basophil responsiveness via FcεRI stimulation in FRs was not observed in peripheral blood basophils preincubated with omalizumab in vitro, suggesting that omalizumab does not directly affect circulating pre-existing abnormal basophils.

CONCLUSION

Increased basophil responsiveness via FcεRI after omalizumab treatment is associated with the therapeutic effect and mechanism of action of omalizumab.

Combination therapy with omalizumab and an immune-suppressive agent for resistant chronic spontaneous rrticaria - A real-life experience

Background

Chronic Spontaneous Urticaria (CSU) is a relatively common immune mediated disease that can be effectively treated nowadays. Nevertheless, for some patients remission cannot be achieved following current treatment recommendations, defined as resistant CSU (r-CSU). Treating r-CSU is challenging, and, currently, there are no recommended interventions. In this real-life study we describe successful therapy of 18 r-CSU patients using an "intensified protocol" of anti-IgE-antibody (omalizumab) concomitantly with an immunosuppressant. We defined the r-CSU phenotype and compared it to omalizumab-responsive CSU (Or-CSU) phenotype.

Methods

Clinical and serological data of 72 CSU patients (ie, 18 r-CSU and 54 age and sex matched Or-CSU) were retrospectively collected and analyzed. All patients were diagnosed with CSU for ≥6 months and treated at the Sheba Medical Center during 2013–2018.

Results

Of 289 CSU patients, 18 (6%) were diagnosed with r-CSU and treated with the "intensified protocol" including omalizumab and cyclosporine-A (16p), methotrexate (1p), and azathioprine (1p). Of which, 14/18 (78%) achieved complete remission, 2/18 (11%) partial remission, and 2/18 (11%) no remission. During follow-up no serious adverse events were documented. r-CSU patients received higher doses of antihistamine (p < 0.0001) and omalizumab (425 ± 58 mg/month vs. 283 ± 86 mg/month; p < 0.0001) compared to Or-CSU. The r-CSU phenotype was linked with concomitant autoimmunity (p = 0.0005) and a lower level of IgE prior to initiation of therapy (p = 0.027).

Conclusion

r-CSU may be a distinct CSU phenotype characterized by severe disease, concomitant autoimmunity, and lower baseline-IgE levels (low "autoallergy"). An "intensified protocol" with omalizumab and an immunosuppressive agent was found to be efficacious and safe for r-CSU. Further larger studies are required to verify these results.

An update on biological therapies for pediatric allergic diseases

Allergic diseases represent a global health burden. Patients with allergic diseases may experience disability, reduced quality of life and productivity, emotional distress, and social restrictions, especially in the most severe cases. Current advances in unveiling the pathogenesis of allergic disorders have paved the way for the development of novel therapeutic strategies. Biological drugs have been widely studied in pediatric allergic asthma, with strong evidence of efficacy and safety. Moreover, promising results derive from studies on other conditions such as atopic dermatitis, chronic spontaneous urticaria, and food allergy. This review analyzes recent evidence on the role of biologic therapies for allergic diseases, focusing on the pediatric age.

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.

The Relation of Autologous Serum Skin Test and Autologous Plasma Skin Test Result with Various Clinical and Laboratory Findings in Patients with Chronic Spontaneous Urticaria

Background

Despite the autologous serum skin test (ASST) and autologous plasma skin test (APST) is widely used test accessing whether a patient with chronic spontaneous urticaria (CSU) has autoreactivity or not, the clinician often encounter difficulty making correlation between the test result and clinical implications.

Objective

This study was aimed to find any clinical and laboratory findings related to the ASST and APST response. Agreement and correlation between the two tests was also analyzed.

Methods

A retrospective study was conducted on 300 CSU patients who underwent ASST, APST. The subjects were divided into four groups according to the skin test result. Also, the degree of serum and plasma response was recorded.

Results

Both ASST and APST positive group had shorter duration of the disease, higher incidence of at least one episode of angioedema than negative group. There were no significant differences in the positivity for autoantibodies including antinuclear, ds-DNA, and thyroid-related between the two groups. The predicted positive rate of ASST and APST according to age showed bimodal peak and decreasing pattern according to disease duration. Predicted positivity of both tests declined with increase in total immunoglobuline E (IgE) level. In the correlation study, the two tests showed high correlation coefficients.

Conclusion

ASST and APST positivity may be related to disease duration and severity of CSU. The two tests showed a generally consistent result. Autoreactivity may be gradually lost as disease continues. We suggest the autoreactivity in CSU could arise independently from IgE mediated immune process.

Omalizumab in children and adolescents with chronic spontaneous urticaria: Case series and review of the literature

The recent EAACI/GA² LEN/EDF/WAO guidelines recommend omalizumab (anti-IgE) for the management of patients aged ≥12 years with chronic urticaria unresponsive to high-doses second-generation H₁ -antihistamines (antiH₁ ). However, there is little published information on the success of omalizumab for such a treatment in children. We reported our experience of six patients with chronic spontaneous urticaria (CSU) treated with omalizumab. Mean age of our case series was 14.7 years (range 11-16 years) with a prevalence of male gender (66.7%). All six patients were treated with at least one 6-months course of omalizumab. The average follow-up period was 13 ± 6 months. Only one patient was no responder to omalizumab therapy. Thus far, two patients have experienced a complete CSU regression over 12 months after the final omalizumab administration. The remaining three patients needed a second course of treatment. Our experience demonstrates that omalizumab is effective and safe as treatment option for CSU unresponsive to antiH₁ , even in adolescent age.

H. Grattan C, Jakob T, Konstantinou GN, Raap U, Skov PS, Staubach P, Kromminga A, Zhang K, Bindslev‐Jensen C, Daschner A, Kinaciyan T, Knol EF, Makris M, Marrouche N, Schmid‐Grendelmeier P, Sussman G, Toubi E, Church MK, Maurer M. Biomarkers and clinical characteristics of autoimmune chronic spontaneous urticaria: Results of the PURIST Study

BACKGROUND

Autoimmune chronic spontaneous urticaria (aiCSU) is an important subtype of chronic spontaneous urticaria (CSU) in which functional IgG autoantibodies to IgE or its high-affinity receptor (FcεRI) induces mast cell degranulation and subsequent symptom development. However, it has not been tightly characterized. This study aimed to better define the clinical and immunological features and to explore potential biomarkers of aiCSU.

METHODS

This was a multinational, multicenter study of 182 CSU patients. The clinical features studied included: urticaria activity and impact (UAS7 and quality of life); autologous serum skin test (ASST); IgG anti-FcεRI and IgG anti-IgE; IgG-anti-thyroperoxidase (IgG anti-TPO); total serum IgE; and basophil reactivity (BASO) using the basophil activation test (BAT) and basophil histamine release assay (BHRA).

RESULTS

Of the 182 patients, 107 (59%) were ASST+, 46 (25%) were BASO+, and 105 (58%) were IgG anti-FcεRI+/IgE+. Fifteen patients (8%) fulfilled all three criteria of aiCSU. aiCSU patients appeared more severe (UAS7 21 vs 9 P < 0.016) but showed no other clinical or demographic differences from non-aiCSU patients. aiCSU patients also had markedly lower total IgE levels (P < 0.0001) and higher IgG anti-TPO levels (P < 0.001). Of biomarkers, positive BAT and BHRA tests were 69% and 88% predictive of aiCSU, respectively.

CONCLUSIONS

aiCSU is a relatively small but immunologically distinct subtype of CSU that cannot be identified by routine clinical parameters. Inclusion of BHRA or BAT in the diagnostic workup of CSU patients may aid identification of aiCSU patients, who may have a different prognosis and benefit from specific management.

Biomarkers In Chronic Spontaneous Urticaria: Current Targets And Clinical Implications

Chronic urticaria (CU) is a mast cell-driven disease characterized by the development of wheals, angioedema, or both for more than 6 weeks. The two major sub-types are chronic spontaneous urticaria (CSU) and inducible urticaria. In the last decade different pathophysiological mechanisms, potentially responsible for the development of the disease, have been described. It is likely that the activation of mast cells and basophils in CSU can be the results of immune system dysregulation, activation of the inflammatory cascade, and of the extrinsic coagulation pathway. Some of the mediators involved in the pathophysiological mechanisms of CSU have recently been identified as potential biomarkers useful for the diagnosis, follow-up, and management of the disease, even if they are not yet available in clinical practice. Thus, in this review we discuss new insights in the mediators involved in the pathogenesis of CSU, highlighting their potential role as biomarkers in the activity and progression of the disease and response to therapies.

The Real-Life Effectiveness and Safety of Omalizumab Updosing in Patients With Chronic Spontaneous Urticaria

Background:

Omalizumab is a third-line treatment for chronic spontaneous urticaria (CSU). Studies investigating the use of higher doses of omalizumab in patients unresponsive to regular doses are limited.

Objectives:

This study aims to investigate the effectiveness and safety of omalizumab 450 mg in CSU.

Methods:

A retrospective cohort study was conducted. The response to therapy was evaluated using the Urticaria Activity Score over 7 days (UAS7) and the Urticaria Control Test (UCT). Patients showing complete response (CR) (UAS7: 0-1) to omalizumab 300 mg (Group 1) and patients receiving at least 3 doses of omalizumab 450 mg (Group 2) between 2016 and 2018 were included.

Results:

A total of 72 patients (Group 1: 59; Group 2: 13) were included. In Group 2, the mean UAS7 score decreased from 18.6 to 5.1 and the mean UCT score increased from 8.6 to 12 after a mean 4.3 courses of 450 mg omalizumab treatment. Of the 13 patients in Group 2, 6 had CR and 3 had good disease control (UAS7: 2-6). The rate of patients with low baseline IgE levels (< 43 IU/mL) was significantly higher in Group 2.

Conclusions:

Higher doses of omalizumab are effective and safe in patients with CSU that is unresponsive to omalizumab 300 mg. Lower baseline total IgE levels might be used as a predictor of nonresponse to omalizumab and the need for higher doses.

Treatment of chronic spontaneous urticaria with an inadequate response to H1-antihistamine

The second-generation H1-antihistamines (sgAH) are the first-line symptomatic treatment of patients with chronic spontaneous urticaria (CSU). Up to 50% of the patients will not respond to licensed doses of sgAH. According to the guidelines, the dose of sgAH may be increased up to 4 times the conventional dose. However, even at higher doses, there is a subgroup of patients refractory to the antihistamine treatment. The purpose of this article was to review the different treatment options of antihistamine-refractory CSU patients. This revision examines the available literature for therapies used in chronic urticaria, including omalizumab, ciclosporin A, oral glucocorticoids, leukotriene receptor antagonists, H2 antihistamines, doxepin, dapsone, hydroxychloroquine, phototherapy, methotrexate, mycophenolate mofetil, azathioprine, autohemotherapy, intravenous immunoglobulins and rituximab, between others. After the exhaustive review of the medical literature only few high-quality studies have been identified, mostly for omalizumab. Omalizumab is an anti-immunoglobulin E monoclonal antibody, approved for the treatment of CSU, that has radically changed the management of the patients without good response to sgAH, allowing to reach complete responses in a high percentage of patients. Although actually the therapeutic management of CSU is more effective and safer than before 2014, there is place even for new and more effective treatments. A good number of partial responders and slow responders to omalizumab and a little percentage still of non-responders to available therapies stimulate the development of new drugs that will also be discussed.

Emerging Therapies in Chronic Spontaneous Urticaria

Chronic spontaneous urticaria (CSU) is characterized by typically short-lived and fleeting wheals, angioedema or both, which occur spontaneously and persist for longer than 6 weeks. This term is applied to the most common subtype of chronic urticaria. The underlying pathophysiology for CSU involves mast cell and basophil degranulation with release of histamine, leukotrienes, prostaglandins and other inflammatory mediators. Although a variety of treatments exist, many patients do not tolerate or benefit from the existing therapies and even require more effective treatments. Omalizumab is currently the only licensed biologic for antihistamine-refractory CSU, and novel drugs are under development. This article reviews its current status regarding pathogenesis and approach to treatment as well as therapeutic agents that are under development for the treatment of CSU.