Omalizumab in patients with chronic spontaneous urticaria nonresponsive to H1‐antihistamine treatment: results of the phase IV open‐label SUNRISE study

Spectrum and Impact of Reported Side Effects of Omalizumab in Patients With Chronic Urticaria: A Long-Term Multicentre Real-World Study

BACKGROUND

Chronic urticaria (CU) treatment with omalizumab is considered safe in short-term studies. Large real-world studies focusing on the long-term safety of omalizumab and associated factors are lacking. We aimed to investigate the spectrum of reported side effects in omalizumab-treated CU patients in a large long-term daily practice cohort.

METHODS

A multinational multicentre retrospective study was conducted at 14 specialised urticaria centres (UCAREs), including all CU patients ever treated with omalizumab until centre-specific data lock. The prevalence of patient-reported side effects was assessed.

RESULTS

A total of 1859 patients were included, of which 32.9% (n = 612) reported side effects during omalizumab treatment with a wide range across centres (0%-75.5%). Fatigue (15.8%, n = 293), headache (11.6%, n = 215) and flu-like symptoms (9.3%, n = 172) were most common. No events suggestive of anaphylaxis and no new notably prevalent side effects were reported. Hair loss was reported by 2.9% (n = 53/1859) of patients, leading to treatment adjustment in 21.1% (n = 8/38 with sufficient data). Patients who reported side effects were more often female (78.3% vs. 68.6%, p < 0.001), had worse disease control prior to omalizumab (Urticaria Control Test, UCT, 4.0 vs. 6.0, p < 0.001), and lower fast response (Weekly Urticaria Activity Score, UAS7, < 7 or UCT > 11 within 4 weeks, 42.6% vs. 59.5%, p < 0.001) and complete/good response rates (UAS7 < 7 or UCT > 11 at end of treatment, 72.3% vs. 84.4%, p < 0.001) compared to patients without side effects. While only 2.4% (n = 44/1859) of patients discontinued treatment due to side effects, 5.5% (n = 100/1859) and 12.8% (n = 238/1859) of patients reporting side effects with insufficient (UAS7 ≥ 7 or UCT 3-11 at end of treatment) and complete/good response, respectively, remained on omalizumab.

CONCLUSIONS

The safety and tolerability of omalizumab was confirmed. Notably, the wide variation in reported side effects across centres suggests that differences in awareness influence reporting. Hair loss was more prevalent than described before, warranting extra attention. Side effects were more often reported in patients whose characteristics suggest reduced effectiveness of omalizumab, possibly related to a negative association with omalizumab and suggesting increased disease burden. Availability of new therapies might increase the impact of side effects on treatment decisions, not only in omalizumab-refractory patients but potentially even among good responders.

The Role of Coagulation/Fibrinolysis Biomarkers in Pathophysiology, Disease Severity, and Treatment Response in Patients with Urticaria: A Scoping Review

The pathology of urticaria is complex. Recently, researchers have widely focused on the role that the coagulation/fibrinolysis system plays in the pathology of urticaria. The potential of coagulation/fibrinolysis biomarkers as disease severity or treatment response biomarkers remains uncertain, lacking comprehensive analysis in previous studies. Hence, we performed a scoping review to thoroughly analyze coagulation/fibrinolysis biomarkers that may predict disease progression and treatment response of urticaria. Data from 71 studies showed that chronic spontaneous urticaria (CSU) was the most-studied subtype (39 articles), with D-dimers being the most researched marker (56 articles). Twenty-one biomarkers were investigated, and ten biomarkers were significantly correlated with disease severity. Specifically, D-dimers (26 articles) and prothrombin fragment 1 + 2 (F1+2) (12 articles) plasma levels increased with exacerbation and decreased with remission. Biomarkers such as D-dimer also correlated significantly with inflammatory cytokines and complement, suggesting interactions among coagulation, immunity, and inflammation in the pathology of urticaria. While these biomarkers may predict treatment response, more evidence is needed. Additionally, anticoagulants such as warfarin, heparin sodium and tranexamic acid have been proved effective for urticaria. This review emphasizes that some coagulation/fibrinolysis biomarkers (such as D-dimer and F1+2) may be not only indicators of disease status but also potential predictors of treatment response. It aims to assist researchers and practitioners in gaining a better understanding of the close relationships among coagulation/fibrinolysis biomarkers, the condition of urticaria (especially chronic urticaria, CU), and its prognosis. It also provides new directions for future research on exploring treatment methods via the coagulation/fibrinolysis pathways.

Factors associated with the efficacy of omalizumab treatment in chronic spontaneous urticaria

BACKGROUND

Omalizumab is a preferred treatment in antihistamine-refractory chronic spontaneous urticaria (CSU) patients. However, factors that may impact treatment response remain to be explored.

OBJECTIVE

This study aimed to examine the factors affecting treatment response in CSU patients receiving omalizumab.

METHODS

This was a retrospective study that included 123 patients who received omalizumab treatment for CSU between January 2015 and April 2024. After administering omalizumab, we evaluated therapeutic efficacy with the urticaria control test (UCT). According to UCT, patients were classified as complete responders, partial responders, and nonresponders.

RESULTS

The median age of the patients was 42 (31-50) years, and there were 77 (62.9%) female patients. Sixty-four (52%) patients exhibited complete response, and 43 (35%) patients exhibited partial response to omalizumab treatment, whereas 16 (13%) patients were nonresponders. Autoimmune disease (AID) was present in 31 (25.2%) patients. The most common AID was thyroid autoimmunity, seen in 24 (77.4%) patients. AID was significantly higher in omalizumab treatment nonresponders than in partial and complete responders. The presence of an autoimmune thyroid disease was an independent risk factor for failure to respond to omalizumab treatment. Baseline IgE levels were significantly higher in omalizumab treatment responders with a complete response compared to those with a partial response and nonresponders.

CONCLUSION

Response to omalizumab treatment was influenced by the presence of an AID and baseline serum total IgE level. A concurrent autoimmune thyroid disease was found to be an independent risk factor affecting failed treatment response. Factors that can predict response to omalizumab treatment can help guide patients to more effective treatment.

Dermatologists' knowledge, attitudes, and practices regarding omalizumab therapy for chronic urticaria

The purpose of this study was to evaluate dermatologists' knowledge, attitudes, and practices (KAP) concerning omalizumab therapy for chronic urticaria. We conducted a cross-sectional study in several hospitals in China, mainly in hospitals in Zhejiang Province, during August 1, 2024 - August 15, 2024 using a self-administered KAP questionnaire. Wilcoxon-Mann-Whitney tests and Kruskal-Wallis analysis of variance were performed to compare differences across groups Factors influencing practice were determined through multivariable logistic regression. The study analyzed 354 valid questionnaires. Among the respondents, 248 (70.06%) were aged between 31 and 35 years, and 269 (75.99%) had 5-10 years of experience. The mean scores for knowledge, attitudes, and practices were 5.71 ± 1.39 (possible range: 0-9), 21.39 ± 2.25 (possible range: 5-25), and 19.84 ± 2.53 (possible range: 5-25), respectively. Multivariate logistic regression indicated that a higher attitude score (OR = 1.929, 95% CI: [1.511-2.462], P < 0.001), being male (OR = 3.262, 95% CI: [1.507-7.059], P = 0.003), and awareness of omalizumab (OR = 4.966, 95% CI: [1.466-16.830], P = 0.010) were significantly associated with proactive practice. Dermatologists demonstrated insufficient knowledge, positive attitudes, and proactive practices towards omalizumab therapy for chronic urticaria. Given the identified knowledge gap, there is a pressing need for targeted educational interventions to enhance dermatologists' understanding of omalizumab therapy for chronic urticaria, aiming to improve patient care and outcomes in clinical practice.

Expression of STAT3, IL27p28 and IL12p35 is deregulated and linked to autoimmune markers in chronic spontaneous urticaria

BACKGROUND

Chronic spontaneous urticaria (CSU) is a common inflammatory disorder characterized by weals, angio-oedema, or both, for more than 6 weeks. Autoimmunity is held to be one of the most frequent causes, but little is known about the expression and relevance of autoimmunity-driving genes in CSU, such as STAT3, STAT1, IL27p28 (IL30) and IL12p35 (IL12A).

OBJECTIVES

To investigate patients with CSU and the expression of STAT3, STAT1, IL27p28 and IL12p35, and possible links to clinical features.

METHODS

We enrolled 26 patients with CSU and 19 healthy controls (HCs) and determined their expression levels of STAT3, STAT1, IL27p28 and IL12p35 by quantitative real-time polymerase chain reaction. Patients were assessed for total IgE and IgG-anti-thyroid peroxidase (TPO), markers of autoimmune CSU.

RESULTS

Patients with CSU showed significantly higher expression of STAT3 but not STAT1: 17 (65%) and 10 (38%) of the 26 had elevated STAT3 expression and STAT3/STAT1 ratios, respectively, as compared with only 1 (5%) of the 19 HCs. High STAT3 expression and STAT3/STAT1 ratios were linked to low IgE and elevated IgG-anti-TPO. As compared with HCs, patients with CSU had markedly lower and correlated IL27p28 and IL12p35 mRNA expression levels. Low IL27p28 and IL12p35 expression levels were linked to higher STAT3/STAT1 ratios and low IgE.

CONCLUSIONS

STAT3 upregulation and higher STAT3/STAT1 ratios, along with IL27p28 and IL12p35 downregulation, clusters with features of autoimmune CSU. The role of STAT3 as a potential pathogenic driver of autoimmune CSU and target of treatment should be explored further.

Quality of life measurement in assessing treatment effectiveness in urticaria: European experts position statement

In this study, the European Academy of Dermatology and Venereology (EADV) Task Forces on Quality of Life and Patient-Oriented Outcomes and Urticaria and Angioedema has examined the Health-Related Quality of Life (HRQoL) measurement in the treatment of urticaria. The Dermatology Life Quality Index was the most frequently used HRQoL instrument in clinical trials on urticaria. Many reports of clinical trials of urticaria gave no exact numeric results related to HRQoL changes, making clear conclusions and comparisons with other studies impossible. The interpretation of HRQoL impairment data is more difficult when assessed by instruments without severity stratification systems. The minimal clinically significant difference (MCID) is a more clinically oriented and relevant parameter than depending on statistically significant changes in HRQoL scores. Therefore, using HRQoL instruments with established MCID data in clinical trials and clinical practice is preferred.

Therapies for Chronic Spontaneous Urticaria: Present and Future Developments

Chronic spontaneous urticaria (CSU) is a complex dermatological condition characterized by recurrent wheals and/or angioedema lasting for more than six weeks, significantly impairing patients' quality of life. According to European guidelines, the first step in treatment involves second-generation H1-antihistamines (sgAHs), which block peripheral H1 receptors to alleviate symptoms. In cases with inadequate responses, the dose of antihistamines can be increased by up to fourfold. If symptoms persist despite this adjustment, the next step involves the use of omalizumab, a monoclonal anti-IgE antibody, which has shown efficacy in the majority of cases. However, a subset of patients remains refractory, necessitating alternative treatments such as immunosuppressive agents like cyclosporine or azathioprine. To address these unmet needs, several new therapeutic targets are being explored. Among them, significant attention is being given to drugs that block Bruton's tyrosine kinase (BTK), such as remibrutinib, which reduces mast cell activation. Therapies like dupilumab, which target the interleukin-4 (IL-4) and IL-13 pathways, are also under investigation. Additionally, molecules targeting the Mas-related G protein-coupled receptor X2 (MRGPRX2), and those inhibiting the tyrosine kinase receptor Kit, such as barzolvolimab, show promise in clinical studies. These emerging treatments offer new options for patients with difficult-to-treat CSU and have the potential to modify the natural course of the disease by targeting key immune pathways, helping to achieve longer-term remission. Further research is essential to better elucidate the pathophysiology of CSU and optimize treatment protocols to achieve long-term benefits in managing this condition. Altogether, the future of CSU treatments that target pathogenetic mechanisms seems promising.

Quality of life measurement in urticaria: Position statement of the European Academy of Dermatology and Venereology Task Forces on Quality of Life and Patient-Oriented Outcomes and Urticaria and Angioedema

The European Academy of Dermatology and Venereology (EADV) Task Forces on quality of life (QoL) and patient-oriented outcomes and on urticaria and angioedema recommendations for the assessment of Health-related (HR) QoL in all patients with urticaria in research and practice are as follows: to use the DLQI for adults and the CDLQI for children as dermatology-specific and the CU-Q2oL as a disease-specific HRQoL instruments in urticaria; to use generic instruments to provide comparison of data on urticaria with non-dermatologic diseases, or to compare with healthy volunteers or the general population; to select validated HRQoL instruments with appropriate age limits; to present exact numeric data for HRQoL results; correct title of any HRQoL instrument should be used, along with its correct abbreviation and the reference to its original publication, where possible. The EADV TFs discourage the use of non-validated HRQoL instruments and modified HRQoL instruments that have not undergone standard validation.

Elevated baseline soluble FcεRI may be linked to early response to omalizumab treatment in chronic spontaneous urticaria

BACKGROUND

Omalizumab, an anti-IgE monoclonal antibody, is an effective treatment in chronic spontaneous urticaria (CSU). Predictors of fast and good response for omalizumab treatment have not yet been identified and characterized.

OBJECTIVE

To evaluate whether soluble FcεRI (sFcεRI), a marker of IgE-mediated mast cell activation, predicts the time of response to omalizumab in CSU.

METHODS

Sera of 67 CSU patients were obtained before omalizumab treatment and analysed for sFcεRI levels by ELISA (2 ng/mL was used as cut-off for elevated sFcɛRI). Treatment response during the first 4 weeks was assessed with the urticaria activity score (UAS7), urticaria control test (UCT) and the rolling UAS7 (rUAS7).

RESULTS

Elevated pre-treatment sFcɛRI levels were detected in more than 70% of patients with completely controlled disease (UCT = 16) and well-controlled disease (UCT = 12-15) and were significantly associated with disease control (χ2  = 4.94, p < 0.05). More than half of the patients (14/25) with low levels had poor disease control (UCT < 12). Of the patients who achieved complete and marked UAS7 response, respectively, 75% and 63% had elevated baseline sFcɛRI levels. Post-treatment UAS7 scores were lower in patients with elevated sFcɛRI levels reaching statistical significance at Week 3 (p < 0.05). Patients with elevated baseline sFcɛRI levels achieved rUAS7 ≤ 6 and = 0 earlier than those with lower levels (Days 9 vs. 13 and Days 12 vs. 14, respectively).

CONCLUSION

Elevated sFcεRI serum levels predict early and good response to treatment with omalizumab, which may help to better design treatment options for CSU patients.

Omalizumab Drug Survival in Chronic Urticaria: A Retrospective Multicentric French Study

BACKGROUND

Omalizumab (OMA) dramatically improves disease control and quality of life in patients with chronic urticaria (CU).

OBJECTIVE

We aimed to evaluate the discontinuation patterns of OMA and their determinants in a cohort of French patients with CU.

METHODS

We conducted a retrospective multicenter study in 9 French tertiary referral hospitals. All patients diagnosed with either spontaneous (CSU) and/or inducible (CIndU) CU who received at least 1 injection of OMA between 2009 and 2021 were included. We analyzed OMA drug survival and investigated possible determinants using Kaplan-Meier curves and log-rank tests.

RESULTS

A total of 878 patients were included in this study; 48.8% had CSU, 10.1% CIndU, and 41.1% a combination of both. OMA was discontinued in 408 patients, but the drug was later reintroduced in 50% of them. The main reason for discontinuing treatment was the achievement of a well-controlled disease in 50% of patients. Half of the patients were still being treated with OMA 2.4 years after the initiation of treatment. Drug survival was shorter in patients with CIndU and in those with an autoimmune background. In atopic patients, OMA was discontinued earlier in patients achieving a well-controlled disease. A longer OMA drug survival was observed in patients with a longer disease duration at initiation.

CONCLUSION

In French patients with CU, the drug survival of OMA appears to be longer than that observed in previous studies conducted elsewhere, highlighting discrepancies in prescription and reimbursement possibilities. Further studies are warranted to develop customized OMA treatment schemes based on individual patterns.

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.

Activation of ryanodine-sensitive calcium store drives pseudo-allergic dermatitis via Mas-related G protein-coupled receptor X2 in mast cells

Mast cell (MC) activation is implicated in the pathogenesis of multiple immunodysregulatory skin disorders. Activation of an IgE-independent pseudo-allergic route has been recently found to be mainly mediated via Mas-Related G protein-coupled receptor X2 (MRGPRX2). Ryanodine receptor (RYR) regulates intracellular calcium liberation. Calcium mobilization is critical in the regulation of MC functional programs. However, the role of RYR in MRGPRX2-mediated pseudo-allergic skin reaction has not been fully addressed. To study the role of RYR in vivo, we established a murine skin pseudo-allergic reaction model. RYR inhibitor attenuated MRGPRX2 ligand substance P (SP)-induced vascular permeability and neutrophil recruitment. Then, we confirmed the role of RYR in an MC line (LAD2 cells) and primary human skin-derived MCs. In LAD2 cells, RYR inhibitor pretreatment dampened MC degranulation (detected by β-hexosaminidase retlease), calcium mobilization, IL-13, TNF-α, CCL-1, CCL-2 mRNA, and protein expression activated by MRGPRX2 ligands, namely, compound 48/80 (c48/80) and SP. Moreover, the inhibition effect of c48/80 by RYR inhibitor was verified in skin MCs. After the confirmation of RYR2 and RYR3 expression, the isoforms were silenced by siRNA-mediated knockdown. MRGPRX2-induced LAD2 cell exocytosis and cytokine generation were substantially inhibited by RYR3 knockdown, while RYR2 had less contribution. Collectively, our finding suggests that RYR activation contributes to MRGPRX2-triggered pseudo-allergic dermatitis, and provides a potential approach for MRGPRX2-mediated disorders.

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.

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.

Dupilumab: An emerging therapy in allergic fungal rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) is a highly resistant disease and is challenging to treat. Patients with recurrent attacks of the disease despite surgical management can benefit from biologics as adjunct therapies. Dupilumab has shown promising endpoints in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP). This case series reports 4 patients with resistant AFRS concomitant with asthma, for which dupilumab therapy was administered. Long-term follow-ups showed that dupilumab improved the symptoms and improved the results of objective tools such as imaging and pulmonary function test.

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.

CCR3-shRNA promotes apoptosis and inhibits chemotaxis and degranulation of mouse mast cells

Mast cells (MCs) are the major effector cells of allergic rhinitis (AR). The present study aimed to investigate the effects of C-C chemokine receptor type 3 (CCR3) on the proliferation, apoptosis, chemotaxis and activated degranulation of mouse MCs. Mouse bone marrow-derived MCs were cultured in vitro, purified and identified using toluidine blue staining and flow cytometry. Three different CCR3-short hairpin (shRNA) lentiviral vectors were constructed and transfected into MCs, and the mRNA and protein expression levels of CCR3 were assessed by reverse transcription-quantitative PCR and western blotting. Proliferation and apoptosis of the MCs were measured using Cell Counting kit-8 (CCK-8) assays and flow cytometry, respectively. MC chemotaxis was assessed by Transwell assay and quantified using flow cytometry. The activation of MC degranulation was examined using ELISAs. The results demonstrated that MCs were appropriately isolated, and identified that CCR3-shRNA2 presented the higher knockdown effect among the three shRNAs tested. Following 96 h of transfection, the results of CCK-8 and flow cytometry assays demonstrated that CCR3-shRNA2 inhibited MC proliferation and promoted MC apoptosis. The results from the Transwell assay indicated that CCR3-shRNA2 restrained MC chemotaxis, whereas ELISA results demonstrated that CCR3-shRNA2 suppressed MC degranulation. In conclusion, CCR3-shRNA2 effectively downregulated CCR3 mRNA and protein expression levels in mouse MCs. In addition, CCR3-shRNA2 promoted MC apoptosis and suppressed the proliferation, chemotaxis and degranulation of mouse MCs, suggesting that CCR3-shRNA2 may serve as a therapeutic tool for the treatment of allergic rhinitis.

Biologicals targeting type 2 immunity: Lessons learned from asthma, chronic urticaria and atopic dermatitis

During the last decades, progression of research has led to great achievements for treatment and therapy of several disabling disorders, particularly in the field of chronic inflammatory diseases. The increased knowledge of the molecular mechanisms operating in such diseases has represented the first step in this process, and the discovery of molecules able to interfere with the natural history of the diseases, has been the second. This review is focused on the effects of biologics on type 2 diseases such as asthma, chronic urticaria and atopic dermatitis, both biologics just approved for clinical application and also those that are currently undergoing clinical trials. We will also discuss aspects and emphasize clinical trials and recently published studies, as well as research that is currently in the progress, which will be highly relevant for basic immunologists. Likewise, we will cover aspects that are pertinent for clinical immunologists and highlight translational studies that are evaluating novel biologicals in animal models.

Predictors of response to omalizumab and relapse in chronic spontaneous urticaria: a study of 470 patients

BACKGROUND

Chronic spontaneous urticaria (CSU) is defined as spontaneous occurrence of wheals and/or angioedema for ≥6 weeks. Omalizumab is a monoclonal anti-IgE antibody effective in refractory CSU, but its mechanism of action and markers predictive of response remain not completely defined.

OBJECTIVES

To correlate baseline levels of two proposed biomarkers, total IgE (bIgE) and d-dimer (bd-dimer), and clinical parameters to omalizumab response and to relapses after drug withdrawal.

METHODS

In this retrospective Italian multicentre study, clinical data were collected in 470 CSU patients, and bIgE and bd-dimer were measured in 340 and 342 patients, respectively. Disease activity was determined by Urticaria Activity Score 7 (UAS7) at week 1 and 12 after omalizumab starting. Relapses were evaluated during a 2- and 3-month interval after a first and a second course of treatment, respectively.

RESULTS

bIgE correlated to a good response to omalizumab since levels were significantly higher in responders than non-responders (P = 0.0002). Conversely, bd-dimer did not correlate to response. There was no correlation between both bIgE and d-dimer and either first or second relapse. Disease duration was significantly longer in patients who experienced either first or second relapse (P < 0.0001 and P = 0.0105, respectively), while baseline UAS7 correlated only to first relapse (P = 0.0023).

CONCLUSIONS

Our study confirms bIgE as a reliable biomarker predicting response to omalizumab in CSU, while it does not support the usefulness of bd-dimer unlike previous findings. CSU duration before omalizumab and baseline UAS7 may be clinical markers of relapse risk.

Two decades with omalizumab: what we still have to learn

From its availability for clinical use nearly two decades ago for severe asthma, omalizumab has gained strong evidence of efficacy and safety in the treatment of severe asthma not controlled by standard-of-care therapy. It has been acknowledged by Global Initiative on Asthma guidelines as add-on therapy against severe uncontrolled asthma. Thanks to controlled trials supporting its efficacy, omalizumab has also been licensed for the treatment of chronic spontaneous urticaria. The optimal duration of treatment in either disease has not been established. Despite its high price, omalizumab appears to be cost-effective in severe uncontrolled asthma as well as in chronic urticaria. The literature suggests a wide range of applications for omalizumab in various disorders regardless of allergic or non-allergic pathophysiology.