Omalizumab for treatment of allergic rhinitis

Unraveling genetic threads: Identifying novel therapeutic targets for allergic rhinitis through Mendelian randomization

Background

Allergic rhinitis (AR) is a pervasive global health issue, and currently, there is a scarcity of targeted drug therapies available. This study aims to identify potential druggable target genes for AR using Mendelian randomization (MR) analysis.

Methods

MR analysis was conducted to assess the causal effect of expression quantitative trait loci (eQTL) in the blood on AR. Data on AR were collected from 2 datasets: FinnGen(R9) (11,009 cases and 359,149 controls) and UK Biobank (25,486 cases and 87,097 controls). Colocalization analysis was utilized to assess the common causal genetic variations between the identified drug target genes and AR. We also employed available genome-wide association studies (GWAS) data to gauge the impact of druggable genes on AR biomarkers and other allergic diseases.

Results

This study employs MR to analyze the relationship between 3410 druggable genes and AR. After Bonferroni correction, 10 genes were found to be significantly associated with AR risk (P < 0.05/3410). Colocalization analysis revealed a significant causal relationship between the expression variation of CFL1 and EFEMP2 genes and AR, sharing direct causal variants (colocalization probability PP.H3 + PP.H4 > 0.8), highlighting their importance as potential therapeutic targets for AR. The CFL1 gene showed a causal link with levels of thymic stromal lymphopoietin (TSLP), eosinophil count, and interleukin-13 (IL-13) (P = 0.016, 7.45E-16, 0.00091, respectively). EFEMP2 was also causally related to eosinophil count, IL-13, and interleukin-17 (IL-17) (P = 0.00012, 0.00091, 0.032, respectively). PheWAS analysis revealed significant associations of CFL1 with asthma, whereas EFEMP2 showed associations with both asthma and eczema. Protein-Protein Interaction (PPI) network analysis further unveiled the direct interactions of EFEMP2 and CFL1 with proteins related to immune regulation and inflammatory responses, with 77.64% of the network consisting of direct bindings, indicating their key roles in modulating AR-related immune and inflammatory responses. Notably, there was an 8.01% significant correlation between immune-related pathways and genes involved in inflammatory responses.

Conclusion

These genes present notable associations with AR biomarkers and other autoimmune diseases, offering valuable targets for developing new AR therapies.

Efficacy and safety of stapokibart (CM310) in uncontrolled seasonal allergic rhinitis (MERAK): an investigator-initiated, placebo-controlled, randomised, double-blind, phase 2 trial

Background

There is no trial to assess the benefits of periodically using biologics during the pollen season in patients with uncontrolled seasonal allergic rhinitis (SAR), who have moderate-to-severe symptoms even after standard-of-care. This trial aimed to evaluate the efficacy and safety of the add-on administration of stapokibart, a humanised monoclonal antibody that targets interleukin-4 receptor alpha, in patients with uncontrolled SAR.

Methods

In this investigator-initiated, randomised, double-blind, placebo-controlled trial, eligible patients received either stapokibart 600-300 mg weekly (QW), every 2 weeks (Q2W), or placebo QW for 4 weeks. All patients were given mometasone furoate nasal spray and loratadine throughout the trial. The primary endpoint was the mean change from baseline in daily reflective total nasal symptom score (rTNSS) during 2-week treatment. Secondary efficacy outcomes included: the mean change from baseline in daily rTNSS during 4-week treatment; the mean changes and the mean percentage changes from baseline during 2-week and 4-week treatment in 1) daily rTNSS and reflective total ocular symptom score (rTOSS), 2) morning (AM)/evening (PM) rTNSS and rTOSS, 3) AM instantaneous total nasal symptom score (iTNSS) and instantaneous total ocular symptom score (iTOSS), 4) individual nasal and ocular symptoms; the change from baseline in Rhinoconjunctivitis Quality of-Life Questionnaire score during 4-week treatment. Exploratory endpoints included the change of prespecified markers related to type 2 inflammation pre- and post-treatment. Safety, immunogenicity, and pharmacokinetics were also evaluated. This study is registered with www.clinicaltrials.gov (NCT05470647).

Findings

Between August 17, 2022, and December 28, 2022, 92 patients with uncontrolled SAR were enrolled from 4 centres in China and randomly assigned to receive stapokibart 600-300 mg QW (n = 31), stapokibart 600-300 mg Q2W (n = 30), or placebo QW (n = 31), of whom 86 (93%) completed the study. Both stapokibart Q2W and QW did not significantly improve mean change from baseline in daily rTNSS compared with placebo in 2 weeks. The least-squares (LS) mean differences (97.5% confidence interval [CI]) compared with placebo were -1.0 (-2.3, 0.2) in stapokibart Q2W group (p = 0.065) and -0.2 (-1.5, 1.0) in stapokibart QW group (p = 0.67). For the secondary outcomes, compared with placebo, stapokibart Q2W presented significant improvements in the mean percentage change from baseline in daily rTNSS in 2 weeks (LS mean difference -12.9%, 95% CI -25.3%, -0.4%, p = 0.043), as well as AM iTNSS over 2 weeks (LS mean difference -17.4%, 95% CI -31.0%, -3.8%, p = 0.013) and 4 weeks (LS mean difference -15.4%, 95% CI -29.0%, -1.9%, p = 0.026). Additionally, the nasal congestion score was significantly lower in stapokibart Q2W than placebo during 2-week (LS mean difference -0.4, 95% CI -0.7, -0.1, p = 0.014) and 4-week (LS mean difference -0.4, 95% CI -0.7, -0.04, p = 0.028) treatment. Treatment-emergent adverse events (TEAEs) occurred in 48% (15/31), 33% (10/30), and 61% (19/31) of patients receiving stapokibart QW, Q2W, and placebo, respectively. Most reported TEAEs were sinus bradycardia, hyperlipidaemia, and blood uric acid increased.

Interpretation

In this phase 2 trial, both stapokibart regimens had an acceptable safety and tolerability profile but did not significantly improve daily rTNSS in patients with uncontrolled SAR. The efficacy of stapokibart in patients with uncontrolled SAR is being further investigated in ongoing phase 3 trials (clinicaltrials.gov, NCT05908032).

Funding

Ministry of Science and Technology of the People's Republic of China; Ministry of Education of the People's Republic of China; National Natural Science Foundation of China; Chinese Academy of Medical Sciences.

Intestinal proline is a potential anti-allergy factor for allergy diagnosis and therapy

Allergy has become a public health problem worldwide, but effective diagnostic and therapeutic approaches are limited currently. Amino acids are essential macronutrients that potentially participated in the allergy process. This work aimed to investigate whether amino acids can be applied as a mediator for allergy diagnosis and therapy. Two cohort studies were performed to investigate the correlation between fecal amino acids and allergy responses, and a spleen cell model was used to validate the role of amino acids in regulating allergy. In a cohort study with 193 volunteers, fecal proline was found to be negatively correlated with serum IgE, and detailed data analysis revealed that people with high-IgE-mediated allergy had decreased odds of high intestinal proline. In another cohort study with distinct allergic and non-allergic individuals, proline concentration was significantly lower in the allergic group. Daily diet and metagenomics analysis showed that the proline intake and microbiota amino acid metabolism were not significantly different, implying that the body’s proline metabolism might be different between allergic and non-allergic individuals. Furthermore, the spleen cell model demonstrated that proline specifically targeted Th2 and Treg activity. Overall, this work revealed a tight correlation between gut proline and serum IgE, indicating proline as a promising biomarker and a potential therapeutic method for allergic diseases.

Cost-Effectiveness Analysis of Omalizumab for Severe Allergic Asthma in Japan Using Real-World Evidence

OBJECTIVES

Omalizumab is a recommended add-on therapy for patients with severe allergic asthma who remain uncontrolled despite treatment with standard of care (SoC). This study evaluated the cost-effectiveness of omalizumab compared with SoC applying real-world clinical outcomes in adult patients with severe allergic asthma in Japan.

METHODS

A validated Markov model was adapted for Japan and compared the cost-effectiveness of omalizumab as an add-on therapy to SoC versus SoC alone using the most recently updated price of omalizumab. A Japanese real-world postmarketing surveillance and a pivotal randomized clinical trial were used as inputs for clinical effectiveness. Japanese life tables and literature were accessed for mortality data and unit costs were extracted from a Japanese insurance claims database. Quality of life data were retrieved from the clinical trial.

RESULTS

In the base case, the incremental cost-effectiveness ratio for omalizumab add-on therapy was ¥2.85 million per quality-adjusted life-year gained (approximately €21 000; 1€ = ¥133.26) compared with SoC alone. The model appeared to be most sensitive to changes in clinically significant severe exacerbation fatality, day-to-day asthma symptom utilities for SoC, discount rates for benefits, day-to-day asthma symptom utilities for omalizumab responders, time horizon, and the annual cost of omalizumab. The results of the probabilistic sensitivity analysis showed that the probability of omalizumab being cost-effective was 93% to 98% at a threshold of ¥5 to ¥6 million (willingness-to-pay for 1 quality-adjusted life-year).

CONCLUSIONS

Omalizumab add-on therapy is cost-effective compared with SoC alone in Japan in severe allergic asthma population who are uncontrolled with high-dose inhaled corticosteroid and other controllers.

Idiopathic anaphylaxis: Diagnosis and management

Introduction: Idiopathic anaphylaxis (IA) is a diagnosis of exclusion and is based on the inability to identify a causal relationship between a trigger and an anaphylactic event, despite a detailed patient history and careful diagnostic assessment. The prevalence of IA among the subset of people who experienced anaphylaxis is challenging to estimate and varies widely, from 10 to 60%; most commonly noted is ∼20% in the adult anaphylactic population. Comorbid atopic conditions, such as food allergy, allergic rhinitis, and asthma, are present in up to 48% of patients with IA. Improved diagnostic technologies and an increased understanding of conditions that manifest with symptoms associated with anaphylaxis have improved the ability to determine a more accurate diagnosis for patients who may have been initially diagnosed with IA. Methods: Literature search was conducted on PubMed, Google Scholar and Embase. Results: Galactose-α-1,3-galactose (α-gal) allergy, mast cell disorders, and hereditary a-tryptasemia are a few differential diagnoses that should be considered in patients with IA. Unlike food allergy, when anaphylaxis occurs within minutes to 2 hours after allergen consumption, α-gal allergy is a 3-6-hour delayed immunoglobulin E-mediated anaphylactic reaction to a carbohydrate epitope found in red meat (e.g., beef, lamb, pork). The more recently described hereditary α-tryptasemia is an inherited autosomal dominant genetic trait caused by increased germline copies of tryptase human gene alpha-beta 1 (TPSAB1), which encodes α tryptase and is associated with elevated baseline serum tryptase. Acute management of IA consists of carrying an epinephrine autoinjector to be administered immediately at the first signs of anaphylaxis. Long-term management for IA with antihistamines and other agents aims to potentially reduce the frequency and severity of the anaphylactic reactions, although the evidence is limited. Biologics are potentially steroid-sparing for patients with IA; however, more research on IA therapies is needed. Conclusion: The lack of diagnostic criteria, finite treatment options, and intricacies of making a differential diagnosis make IA challenging for patients and clinicians to manage.

Mechanisms and Practical Use of Biologic Therapies for Allergy and Asthma Indications

This article presents a concise overview of the important aspects of the immunologic mechanisms targeted by T-helper 2-directed monoclonal antibodies, as well as their practical applications in the treatment of allergic disorders (specifically allergic rhinitis) and asthma. Several of these novel agents treat multiple diseases, so understanding their targets and the underlying disease process can aid patient selection. In addition, the particular targets of the therapeutics seem to be shifting to include not only agents that intervene against inflammatory cytokines or their receptors but also specific molecular epitopes and cellular surface proteins.

Case Report: Off-Label Use of Omalizumab in a 6-Year-Old Boy With ASD Ameliorated Severe Allergic Rhinitis and Subsequently Improved Behavioral Symptoms

Children with ASD have elevated risk for developing allergic symptoms. The severity of allergic symptoms can exacerbate behavioral problems in children with ASD. Omalizumab, an anti-IgE antibody, has previously shown efficacy in treating allergic rhinitis and behavioral problems in a 12-year-old child with ASD. The present case report provides robust characterization of behavioral improvement in a 6-year-old child with ASD, allergic rhinitis, and autoimmune disorder. A 6-year-old boy with ASD and Hashimoto's disease presented to the clinic with severe allergic rhinitis, irritability, and language delay. After other treatments failed to improve symptoms, our patient was treated with omalizumab at 300 mg/month via subcutaneous injection for a total of 6 months. Marked improvement in allergic symptoms were observed at 2 months into treatment and were maintained through the treatment period. At the conclusion of the treatment period, results from multiple behavioral questionnaires, including the SRS-2, ABC, RBS-R, and PSQI, demonstrated substantial improvement in ASD-related behavioral symptoms. In this case, omalizumab markedly improved ASD-related and sleep behavior in a 6-year-old with ASD, allergic rhinitis, and autoimmune disorder. Future studies with larger patient populations are warranted to investigate the efficacy of omalizumab in patients with ASD and allergy symptoms.

Biologics and Allergy Immunotherapy in the Treatment of Allergic Diseases

Allergic diseases represent some of the most chronic and costly chronic conditions. Medical management may require long-term pharmacotherapy, which is often associated with poor adherence. Although medications provide symptomatic control, they do not modify the allergic disease. Patients may prefer disease-modifying treatments that provide lasting benefits after discontinuation. To date, allergy immunotherapy is the only proved disease modification therapy associated with lasting benefits after discontinuation. However, allergy immunotherapy safety and efficacy has only been established in allergic rhinitis, mild to moderate asthma, and some patients with atopic dermatitis.

Novel Biological Therapies in Severe Asthma: Targeting the Right Trait

Asthma is a heterogeneous disease characterized by chronic airway inflammation that results in a wide spectrum of clinical manifestations. Patients with severe asthma represent a substantial share of consumption of healthcare resources and hospitalization. Moreover, these patients are at risk of increased morbidity and mortality. Recently, several phenotypes and endotypes of asthma have been identified. The identification of specific subtypes of asthma is fundamental for optimizing the clinical benefit of novel treatments. Although in most patients the disease can be controlled by some combination of pharmacologic agents, in some 5-10% of patients the disease remains uncontrolled. Several monoclonal antibodies (mAbs) targeting pathogenetic molecules (e.g., IgE, IL-5, IL- 5Rα, IL-4, IL-13, TSLP) are currently available or under development for the treatment of different forms of severe type 2 asthma. The identification of diagnostic and predictive biomarkers (e.g., IgE, blood eosinophil count, FeNO, periostin, etc.) has revolutioned the field of targeted therapy in severe asthma. Monoclonal antibodies targeting Th2-driven inflammation are generally safe in adult patients with moderate-to-severe asthma. The long-term safety of these biologics is a relevant issue that should be addressed. Unfortunately, little is known about non-type 2 asthma. Further studies are needed to identify biomarkers to guide targeted therapies of different forms of non-type 2 asthma.

Dendritic Cell-Mediated Th2 Immunity and Immune Disorders

Dendritic cells (DCs) are the professional antigen-presenting cells that recognize and present antigens to naïve T cells to induce antigen-specific adaptive immunity. Among the T-cell subsets, T helper type 2 (Th2) cells produce the humoral immune responses required for protection against helminthic disease by activating B cells. DCs induce a Th2 immune response at a certain immune environment. Basophil, eosinophil, mast cells, and type 2 innate lymphoid cells also induce Th2 immunity. However, in the case of DCs, controversy remains regarding which subsets of DCs induce Th2 immunity, which genes in DCs are directly or indirectly involved in inducing Th2 immunity, and the detailed mechanisms underlying induction, regulation, or maintenance of the DC-mediated Th2 immunity against allergic environments and parasite infection. A recent study has shown that a genetic defect in DCs causes an enhanced Th2 immunity leading to severe atopic dermatitis. We summarize the Th2 immune-inducing DC subsets, the genetic and environmental factors involved in DC-mediated Th2 immunity, and current therapeutic approaches for Th2-mediated immune disorders. This review is to provide an improved understanding of DC-mediated Th2 immunity and Th1/Th2 immune balancing, leading to control over their adverse consequences.

Omalizumab and unmet needs in severe asthma and allergic comorbidities in Japanese children

Childhood asthma is one condition within a family of allergic diseases, which includes allergic rhinitis, atopic dermatitis, and food allergy, among others. Omalizumab is an anti-IgE antibody therapy that was approved in Japan for children with asthma and added to the Japanese pediatric asthma guidelines in 2017. This review highlights the Japanese clinical perspectives in pediatric allergic asthma, and consideration for allergic comorbidities, and reflects on omalizumab clinical trials in progress to present comprehensive future opportunities.

Biological therapies for atopic dermatitis: An update

Severe atopic dermatitis, which affects both adults and children, is a debilitating disorder with a significant decline of patients' quality of life. Although aetiopathogenic factors are currently a topic of study and interpretation, the main features of atopic eczema are skin barrier disturbance and immune dysregulation. Severe refractory disease that fails to improve with conventional therapy may benefit from biologic therapy. Progress in understanding immunopathology of atopic dermatitis have allowed identification of therapeutic molecular targets in the field of biological therapy. We reviewed the different biological treatments with a focus on novel targeted agents: Systemic immunotherapy (Omalizumab, Dupilumab, Lebrikizumab, Tralokinumab, Nemolizumab, Ustekinumab, Fezakinumab, Tezepelumab, Apremilast, allergen specific immunotherapy), and topical agents (Tofacitinib, Crisaborole).

Investigational drugs for atopic dermatitis

INTRODUCTION

Many novel medications and herbal medicines have claimed efficacy on atopic dermatitis (AD).

AREAS COVERED

This review covers evidence on efficacy of topical and oral forms of novel and investigational drugs. Topical agents include emollients, phosphodiesterase E4 (PDE4) inhibitors, and topical herbs. There is little evidence that ceramides or natural moisturizing factors provide relief in AD. PDE4 inhibitors have shown promise as an effective topical treatment for mild-to-moderate AD with minimal adverse events, and dupilumab as an effective subcutaneous agent for the treatment of moderate-to-severe AD in adult patients with little adverse effects. However, only preliminary data are available for dupilumab in children with AD. The long-term effects of dupilumab are also not known. Potential new systemic treatments include a number of herbal concoctions.

EXPERT OPINION

Randomized, double-blind placebo-controlled trials (RCTs) have demonstrated topical PDE4 inhibitors are effective and safe in the treatment of both children and adults with AD but further evaluations are needed. RCTs have also shown that subcutaneous dupilumab is an effective and safe agent for the treatment of AD in adults. Long-term effects of these topical and systemic investigational drugs are currently unavailable. Regarding herbal medications, scientific methods are often flawed and objective evidence is lacking.

An Update on Anti-IgE Therapy in Pediatric Respiratory Diseases

Anti-IgE treatment represents a major breakthrough in the therapeutic management of severe allergic asthma. Omalizumab is the unique biologic treatment registered for asthma therapy in children. The clinical efficacy and safety of omalizumab treatment in the pediatric population has been extensively documented in specific trials and consistently expanded from real-life studies. In addition, new experimental evidence suggests that omalizumab may also interfere with the cellular and molecular mechanisms underlying airway remodeling. Novel investigational anti-IgE monoclonal antibodies with improved pharmacodynamic properties are in the pipeline, potentially offering alternative mechanisms of modulating IgE pathway.

The aim of this review is to update current knowledge on anti-IgE therapy in pediatric respiratory diseases.

Anaphylaxis secondary to Parietaria judaica (wall pellitory)

Aeroallergens are an unusual cause of anaphylaxis with sparse reports in the literature. We describe a case of suspected anaphylaxis to Parietaria judaica pollen and the difficulties encountered in confirming this diagnosis.

Idiopathic Anaphylaxis

Idiopathic anaphylaxis is a rare life-threatening disorder with symptoms similar to other forms of anaphylaxis. There is lack of a robust evidence base underpinning the treatment of anaphylaxis and even less so for idiopathic anaphylaxis. Much of the evidence therefore comes from relatively small case series and expert opinion. Idiopathic anaphylaxis is a diagnosis of exclusion, requiring a thorough history and careful diagnostic work-up investigating possible triggers and underlying predisposing factors. Key diagnostic tests include skin-prick testing, tests for specific-IgE, component-resolved diagnostics, and in some cases for allergen challenge tests. Other recognized causes of anaphylaxis, such as foods, medications, insect stings, latex, and exercise, should all be considered, as should differential diagnoses such as asthma. While the cause of idiopathic anaphylaxis remains unknown, prompt treatment with intramuscular epinephrine (adrenaline) administered into the anterolateral aspect of the thigh is associated with good prognosis. There may also be a role for H1-antihistamines and corticosteroids as second-line agents. Patients need to be carefully monitored for signs of deterioration and/or a possible protracted or biphasic reaction. Patients with frequent episodes of anaphylaxis (e.g., six or more episodes/year) should be considered for preventive therapy, which may include corticosteroids, H1- and H2-antihistamines, and, in some cases, mast cell stabilizers such as ketotifen. Alternative immune-suppressants (e.g., methotrexate) and anti-IgE may rarely also need to be considered. In many cases, the frequency of anaphylaxis declines such that regular use of corticosteroids can be discontinued after 9–12 months. Pediatric patients should be treated with similar regimens as adults, but with appropriate dose adjustments. Patients should carry their self-injectable epinephrine and other emergency medications at all times in order to deal with emergency situations.

Novel monoclonal treatments in severe asthma

AIM

To provide a general overview of the current biological treatments and discuss their potential anti-asthmatic effects.

DATA SOURCES

We reviewed articles in PubMed found using the search words "Asthma/therapy AND antibodies, monoclonal/therapeutic use AND cytokines."

STUDY SELECTIONS

Only articles published in English since 2000 were considered. The search identified 29 studies; 8 additional studies were found by hand search, generating 37 studies.

RESULTS

Of the 37 studies investigating biological treatments of asthma, 5 were on the effects of anti-IgE (omalizumab); 12 on anti-IL-5; 8 on anti-IL-13; 5 on anti-IL-4R-α; 3 on anti-IL-9; one on TNF-α; one on anti-IL-2R-α; one on TSLP (Thymic Stromal Lymphopoietin); and one on OX40L. Sample sizes ranged from 3 to 943 participants. Studies of therapies targeting IgE, IL-2, IL4R-α, IL-5, and IL-13 showed some efficacy, whereas those targeting TSLP, IL-9, and TNF-α lacked convincing effectiveness.

CONCLUSION

Research on the biological treatment of asthma shows promising results. While anti-IgE (omalizumab) has been used in the treatment of asthma for some years, anti-IL-5 has recently been approved for use. The efficacy of results of other large studies with a longer duration is needed to draw a firm conclusion. Such studies should not only focus on clinical outcomes, but also consider asthma-related quality of life. Knowledge on the asthma phenotypes and identification of biomarkers associated with these will be useful for physicians considering the right treatment for the asthma patient.

Biological Modulators in Eosinophilic Diseases

Eosinophils can regulate local and systemic inflammation, and their presence in higher numbers appears to play an important role in the pathology of various atopic and inflammatory diseases. Eosinophil maturation, recruitment, and survival depend on several cytokine regulators, including interleukin (IL)-5, IL-4, and IL-13 as well as growth factors such as GM-CSF. Over the last decade, the approach to treating eosinophilic diseases has changed greatly. A number of biologic modulators have been developed to target eosinophilic inflammatory pathways, and their usage has resulted in variable clinical improvement in the treatment of eosinophilic-associated conditions. Novel targeted therapies that are safe and effective for treating these disorders are being investigated. This review summarizes the clinical use of biologic agents that have been studied in clinical trials or approved for treating eosinophilic diseases.

Off-Label Uses of Omalizumab

The off-label use of medicines is a common and extensive clinical practice. Omalizumab has been licensed for use in severe allergic asthma and chronic urticaria. Omalizumab dosing was based on body weight and baseline serum IgE concentration. All patients are required to have a baseline IgE between 30 and 700 IU/ml and body weight not more than 150 kg. The use of off-label drugs may lead to several problems including adverse effects and an increased risk/benefit balance. In this article, there are summarized off-label uses of omalizumab in the last recent years in diseases in which IgE maybe or certainly has a corner role such as allergic rhinitis, allergic bronchopulmonary aspergillosis, anaphylaxis, keratoconjunctivitis, food allergy, drug allergy, urticaria, angioedema, non-atopic asthma, atopic dermatitis, nasal polyps, Churg-Strauss syndrome, eosinophilic otitis media, chronic rhinosinusitis, bullous pemphigoid, contact dermatitis, and others. Use in pregnancy asthmatic women and pre-co-administration with specific immunotherapy will also be revised.

Immunogenicity of a peptide-based anti-IgE conjugate vaccine in non-human primates

The anti-human immunoglobulin E (IgE) monoclonal antibody, omalizumab (Xolair®, Genentech, South San Fransisco, CA), is effective in the treatment of poorly controlled moderate to severe allergic asthma and chronic idiopathic urticaria. It acts by specifically binding to the constant domain (Cϵ3) of free human IgE in the blood and interstitial fluid. Although efficacious, use of omalizumab is limited due to restrictions on patient weight and pre-existing IgE levels, and frequent dosing (q2-4 weeks). A vaccine inducing anti-IgE antibodies has the potential for similar clinical benefits with less frequent dosing and relatively lower cost of goods. We developed a vaccine containing two IgE peptide-conjugates targeting the Cϵ3 domain of human IgE. As part of preclinical evaluation of the vaccine to optimize formulation and dose prior to initiating clinical studies, we evaluated the vaccine in non-human primates, and demonstrate the induction of anti-peptide antibodies that can bind to conformationally intact human IgE and are capable, at least in some animals, of substantial lowering circulating IgE levels.

Monoclonal antibodies: the new magic bullets for allergy: IUPHAR Review 17

Allergic diseases and conditions are widespread and their incidence is on the increase. They are characterized by the activation of mast cells resident in tissues and the consequent infiltration and stimulation of several inflammatory cells, predominantly eosinophils. Cell-cell cross-talk and the release of mediators are responsible for the symptoms and for the modulation of the response. The gold standard of therapeutic intervention is still glucocorticosteroids, although they are not effective in all patients and may cause numerous side effects. Symptomatic medications are also widespread. As research has led to deeper insights into the mechanisms governing the diseases, new avenues have been opened resulting in recent years in the development of monoclonal antibodies (mAbs) such as anti-IgE mAbs (omalizumab) and others still undergoing clinical trials aimed to specifically target molecules involved in the migration and stimulation of inflammatory cells. In this review, we summarize new developments in the field of anti-allergic mAbs with special emphasis on the treatment of asthma, particularly severe forms of this condition, and atopic dermatitis, which are two unmet clinical needs.

From IgE to clinical trials of allergic rhinitis

The current scientific research is continuously aiming at identifying new therapeutic targets with the purpose of modifying the immune response to allergens. The evolution in immunological methods has led to the identification of immunoglobulin E (IgE) as both a diagnostic biomarker and potential therapeutic target in allergic diseases, such as allergic rhinitis. Allergen immunotherapy has been used for more than 100 years to treat allergic diseases and it is today considered the only disease-modifying treatment capable of inducing a long-lasting immunological and clinical tolerance toward the causal allergen. During the past 20 years, major advances have been made in understanding the molecular and cellular mechanisms of allergen tolerance in humans. Moreover, there has been considerable progress in allergen extract modifications and additions to standard extracts. The recognition that IgE plays a pivotal role in basic regulatory mechanisms of allergic inflammation has recently stimulated research into the therapeutic potential of directly targeting this antibody. Omalizumab, the most advanced humanized anti-IgE monoclonal antibody, is currently approved for the treatment of uncontrolled allergic asthma and chronic spontaneous urticaria. Interesting results also arise from studies in which omalizumab was administered in patients with allergic rhinitis. The aim of this review is to provide an update on current findings on immunological and clinical effects of allergen immunotherapy and anti-IgE therapy, which have been shown to have synergistic modes of action for the treatment of allergic rhinitis.

Omalizumab for severe allergic asthma in clinical trials and real-life studies: what we know and what we should address

Randomized clinical trials (RCTs) are the gold standard for the assessment of any therapeutic intervention. Real-life (R-L) studies are needed to verify the provided results beyond the experimental setting. This review aims at comparing RCTs and R-L studies on omalizumab in adult severe allergic asthma, in order to highlight the concurring results and the discordant/missing data. The results of a selective literature research, including "omalizumab, controlled studies, randomized trial, real-life studies" as key words are discussed. Though some similarities between RCTs and R-L studies strengthen omalizumab efficacy and safety outcomes, significant differences concerning study population features, follow-up duration, local adverse events and drop-out rate for treatment inefficacy emerge between the two study categories. Furthermore the comparative analysis between RCTs and R-L studies highlights the need for further research, concerning in particular long-term effects of omalizumab and its impact on asthma comorbidities.

Omalizumab in children

Omalizumab is a recombinant humanized monoclonal antibody that reduces levels of circulating immunoglobulin E (IgE) and expression of IgE high-affinity receptors on mast cells and basophils, interrupting the subsequent allergic inflammatory cascade. Current indications for treatment with omalizumab in pediatric patients are clearly defined and are confined to moderate-to-severe uncontrolled allergic asthma and chronic spontaneous urticaria (CSU). Any other prescription can only be off label. Data available from clinical trials conducted in children suggest that omalizumab is clinically effective and generally well tolerated. Given its mechanism of action, recent reports have suggested its possible clinical use in other IgE-mediated disorders, such as allergic rhinitis, food allergy, and anaphylaxis. In recent years, several studies have also investigated the possible applications of omalizumab in a number of non IgE-mediated diseases. The aim of the present review is to assess all applications of omalizumab as therapy in the pediatric population. The approved indications--allergic asthma and CSU--are reviewed. Moreover, further potential applications of omalizumab are discussed in both IgE-mediated and non-IgE-mediated diseases.

Potential benefit of omalizumab in respiratory diseases

OBJECTIVE

To provide an overview of primary and secondary mechanisms associated with anti-IgE therapy and their relation to other potential indications in diseases affecting the respiratory tract.

DATA SOURCES

Literature from PubMed searches for publications providing insight into secondary mechanisms resulting from anti-IgE therapy and publications reporting on the use of omalizumab to treat conditions that affect the respiratory tract, other than severe atopic asthma.

STUDY SELECTIONS

Clinical trials or case reports were identified for asthma in patients without atopy, allergic rhinitis, nasal polyposis, and allergic bronchopulmonary aspergillosis.

RESULTS

There is substantial evidence from controlled trials supporting a benefit for allergic rhinitis. Case reports and series on more than 50 patients with allergic bronchopulmonary aspergillosis have been published, including patients with or without cystic fibrosis; most have reported benefits in terms of decreased steroid use, exacerbation rates, and, in patients with cystic fibrosis, improvement in lung function. Several small controlled studies on nasal polyposis have shown equivocal results. One small controlled trial in patients with nonatopic asthma showed a significant improvement for lung function but not in exacerbation rate or asthma scores.

CONCLUSION

Recent insight into the immunopathology of respiratory diseases should be used to identify patient populations likely to respond to anti-IgE therapy. Controlled clinical trials are needed to confirm efficacy and determine the clinical significance of the effects of omalizumab in these populations.

mRNA transcript therapy

mRNA is the central molecule of all forms of life. It is generally accepted that current life on Earth descended from an RNA world. mRNA, after its first therapeutic description in 1992, has recently come into increased focus as a method to deliver genetic information. The recent solution to the two main difficulties in using mRNA as a therapeutic, immune stimulation and potency, has provided the basis for a wide range of applications. While mRNA-based cancer immunotherapies have been in clinical trials for a few years, novel approaches; including, in vivo delivery of mRNA to replace or supplement proteins, mRNA-based generation of pluripotent stem cells, or genome engineering using mRNA-encoded meganucleases are beginning to be realized. This review presents the current state of mRNA drug technologies and potential applications, as well as discussing the challenges and prospects in mRNA development and drug discovery.

Current status of therapy with omalizumab in children

PURPOSE OF REVIEW

There are a considerable number of patients with moderate-to-severe uncontrolled asthma needing additional therapy. Omalizumab, an anti-IgE monoclonal antibody, improves control while reducing IgE-mediated airway inflammation and potentially interfering in the progressive remodeling process. The clinical implications are reductions in the required doses of inhaled steroids, a decrease in exacerbation number, and a reduction in emergency room visits and hospitalizations. In addition to its use in asthma, there is an increasing interest on the use of omalizumab for other uncontrolled IgE-mediated diseases, supported by the favorable risk-benefit background. The present review explores the most recent publications on the use of omalizumab for allergic asthma and other atopic conditions in children.

RECENT FINDINGS

Omalizumab has also shown efficacy in allergic rhinitis, and it is being investigated in the treatment of anaphylaxis, food allergy, atopic dermatitis, and chronic spontaneous urticaria, as well as cystic fibrosis and allergic bronchopulmonary aspergillosis. Despite the benefits shown so far, more data are needed for optimal use in these conditions, particularly looking at the safety issues that have to be confirmed.

SUMMARY

Confirmatory evidence on the efficacy and safety of omalizumab in children is reviewed, as well as newest fields of applicability in which IgE is involved in disease mechanism.

Management of allergic rhinitis

In this paper, we review the current management of allergic rhinitis and new directions for future treatment. Currently, management includes pharmacotherapy, allergen avoidance and possibly immunotherapy. The simple washing of nasal cavities using isotonic saline provides a significant improvement and is useful, particularly in children. The most effective medication in persistent rhinitis used singly is topical corticosteroid, which decreases all symptoms, including ocular ones. Antihistamines reduce nasal itch, sneeze and rhinorrhea and can be used orally or topically. When intranasal antihistamine is used together with topical corticosteroid, the combination is more effective and acts more rapidly than either drug used alone. Alternative therapies, such as homeopathy, acupuncture and intranasal carbon dioxide, or devices such nasal air filters or intranasal cellulose, have produced some positive results in small trials but are not recommended by Allergic Rhinitis and its Impact on Asthma (ARIA). In the field of allergic immunotherapy, subcutaneous and sublingual routes are currently used, the former being perhaps more efficient and the latter safer. Sublingual tablets are now available. Their efficacy compared to standard routes needs to be evaluated. Efforts have been made to develop more effective and simpler immunotherapy by modifying allergens and developing alternative routes. Standard allergen avoidance procedures used alone do not provide positive results. A comprehensive, multi-trigger, multi-component approach is needed, including avoidance of pollutants such as cigarette smoke.

Current recommendations and emerging options for the treatment of allergic rhinitis

Allergic rhinitis (AR) is one of the most common diseases and represents a global health problem, currently affecting up to 30% of the general population, with a continuously increasing prevalence and significant comorbidities and complications. The aim of this review is to provide an update on AR treatment, with a focus on current therapies defined by AR and its impact on asthma guidelines and with a particular emphasis on new and future therapeutic perspectives.

Immunotherapy in allergy and cellular tests: state of art

The basophil activation test (BAT) is an in vitro assay where the activation of basophils upon exposure to various IgE-challenging molecules is measured by flow cytometry. It is a cellular test able to investigate basophil behavior during allergy and allergy immunotherapy. A panoply of critical issues and suggestive advances have rendered this assay a promising yet puzzling tool to endeavor a full comprehension of innate immunity of allergy desensitization and manage allergen or monoclonal anti-IgE therapy. In this review a brief state of art of BAT in immunotherapy is described focusing onto the analytical issue pertaining BAT performance in allergy specific therapy.

Treating severe allergic asthma with anti-IgE monoclonal antibody (omalizumab): a review

Increased asthma severity is not only associated with enhanced recurrent hospitalization and mortality but also with higher social costs. Several cases of asthma are atopic in nature, with the trigger for acute asthma attacks and chronic worsening of inflammation being allergens inducing an immune, IgE mediated response. Anti-inflammatory treatments are effective for most of asthma patients, but there are subjects whose disease is incompletely controlled by inhaled or systemic corticosteroids and these patients account for about 50% of the healthcare costs of asthma. Omalizumab is a biological engineered, humanized recombinant monoclonal anti-IgE antibody developed for the treatment of allergic diseases and with clear efficacy in adolescent and adult patients with severe allergic asthma. The anti-IgE antibody inhibits IgE functions blocking free serum IgE and inhibiting their binding to cellular receptors. By reducing serum IgE levels and IgE receptor expression on inflammatory cells in the context of allergic cascade, omalizumab has demonstrated to be a very useful treatment of atopic asthma, improving quality of life of patients with severe persistent allergic asthma that is inadequately controlled by currently available asthma medications. Several trials have demonstrated that this therapy is well tolerated and significantly improves symptoms and disease control, reducing asthma exacerbations and the need to use high dosage of inhaled corticosteroids.

Omalizumab management beyond clinical trials: the added value of a network model

BACKGROUND

Omalizumab is effective and safe in severe allergic asthma. Few data are available about its impact on lung function and on asthma comorbidities, long-term follow-up of treated patients, adherence, non-responders profile, and optimal treatment duration.

OBJECTIVE

We aimed at evaluating omalizumab-related clinical outcomes and unmet needs in a real-life setting.

METHODS

We created a collaborative network (NEONet - North East Omalizumab Network) involving 9 Allergy and Respiratory referral centres for severe asthma placed in the North-East of Italy. Patients' data were entered into a common study database shared by all the participating physicians. A preliminary retrospective analysis was performed.

RESULTS

Patients come from a common well-defined geographical and environmental district providing a homogeneous population sample. A moderate but statistically significant improvement of the FEV1, and an increasing proportion of exacerbations-free patients were observed since the treatment start. These findings were independent of the baseline severity of bronchial obstruction. A positive impact of omalizumab on rhinitis in patients with both asthma and rhinitis was detected. Moreover the efficacy of omalizumab on asthma seemed not to be affected by the baseline severity of rhinitis.

CONCLUSION

Our retrospective analysis represents a preliminary report from the NEONet activity. It confirmed omalizumab efficacy and provided some new insights about its impact on lung function and on comorbid rhinitis. The network approach, under a prospective view, allows creating a large uniform database, by means of a standardized shared tool for data collecting, and joining a multidisciplinary expertise.

IgE Generation and Mast Cell Activation

IgE is an important marker for allergy and plays a central role in the induction of allergic diseases through its binding of the high affinity receptor on mast cells. Mast cells can influence B cell survival, proliferation and differentiation into CD138+cells. Among TH2 cytokines, interleukin (IL)-4 and IL-13 are responsible for class-switching in B cells which resolves in production of allergen-specific IgE antibodies that bind to specific receptor on mast cells. IgE synthesis by B cells is regulated by CD40 ligand, IL-4 and interferon-gamma, therefore inhibition of B cell antigen-specific IgE may prevent the cleavage of CD23 from B cells, having a therapeutic impact which also includes the removal of circulating free IgE, omalizumab, corticosteroids, mast cell stabilizers, leukotriene receptor antagonist, and others. B cell differentiation into IgE-producing cells requires two signals provided by TH2 cells and IL-4, however IL-4, IL-1 and IL-10 as well as several hormones are critical for the development of TH2 cells, while cytokines, such as interferon (IFN)-alpha, IFN-gamma, IL-12 and transforming growth factor (TGF)-beta play a negative role. However, the exact mechanism of this process has not yet been defined.

Basophils and allergic inflammation

Basophils were discovered by Paul Ehrlich in 1879 and represent the least abundant granulocyte population in mammals. The relative rarity of basophils and their phenotypic similarities with mast cells resulted in this cell lineage being historically overlooked, both clinically and experimentally. However, recent studies in human subjects and murine systems have shown that basophils perform nonredundant effector functions and significantly contribute to the development and progression of TH2 cytokine-mediated inflammation. Although the potential functions of murine and human basophils have provoked some controversy, recent genetic approaches indicate that basophils can migrate into lymphoid tissues and, in some circumstances, cooperate with other immune cells to promote optimal TH2 cytokine responses in vivo. This article provides a brief historical perspective on basophil-related research and discusses recent studies that have identified previously unappreciated molecules and pathways that regulate basophil development, activation, and function in the context of allergic inflammation. Furthermore, we highlight the unique effector functions of basophils and discuss their contributions to the development and pathogenesis of allergic inflammation in human disease. Finally, we discuss the therapeutic potential of targeting basophils in preventing or alleviating the development and progression of allergic inflammation.

Inhibition of IL-32 and TSLP production through the attenuation of caspase-1 activation in an animal model of allergic rhinitis by Naju Jjok (Polygonum tinctorium)

In this study, we investigated the effects of Naju Jjok (Polygonum tinctorium Lour., NJJ) on interleukin (IL)-32 and thymic stromal lymphopoietin (TSLP) levels associated with allergic rhinitis (AR). Using female BALB/c mice, we created an animal model of ovalbumin (OVA)-induced AR. Prior to the callenge with OVA, the mice were administered, either nasally or orally with NJJ. In addition, we also used the eosinophilic cells line, Eol-1, stimulated with granulocyte‑macrophage colony-stimulation factor (GM-CSF). The mRNA and protein levels of inflammatory cytokines and markers [interleukin (IL)-32, IL-4, macrophage-inflammatory protein-2 (MIP-2), intercellular adhesion molecule-1 (ICAM-1), and cyclooxygenase-2 (COX-2)] were measured by RT-PCR and western blot analysis, respectively and serum levels were measured by ELISA. The increased levels of IL-32 in the mice with AR and in the stimulated eosinophilic cell line, Eol-1, were significantly reduced by NJJ. TSLP levels were also decreased following the oral administration of NJJ. Mice orally administered NJJ showed markedly alleviated clinical symptoms, such as a reduced number of nasal rubs, decreased spleen weight, decreased serum immunoglobulin E (IgE) levels and decreased serum histamine levels. The oral administration of NJJ significantly decreased the IL-4 levels, while increasing the interferon-γ levels in the spleen. The increased number of eosinophils and mast cells infiltrating the nasal mucosal tissue of the mice with AR were decreased following the oral administration of NJJ. NJJ effectively attenuated caspase-1 activity in the mice with AR and in the stimulated Eol-1 cells. The oral administration of NJJ significantly reduced the levels of inflammatory markers, such as MIP-2, ICAM-1 and COX-2. Furthermore, the intranasal administration of NJJ significantly reduced the early phase response to allergen exposure, such as nasal rubs, IgE production and histamine release, as well as the late phase responses, such as the expression of inflammatory markers. In conclusion, these data demonstrate that NJJ may play a regulatory role in nasal inflammation.