Omalizumab: clinical use for the management of asthma

Research progress of anti-IGE treatment for allergic rhinitis

BACKGROUND

Allergic rhinitis (AR) is an inflammatory reaction of the nasal mainly mediated by Immunoglobulin E(IgE). It is one of the most common chronic diseases in the world. Patients with nasal discomfort, persistent nasal itching, sneezing, runny nose and so on as the main symptoms, it is a refractory allergic disease, will seriously reduce the quality of life of patients.

OBJECTIVE

At present, the treatment of patients with allergic rhinitis is mainly to avoid contact with allergens, drug treatment and desensitization treatment. The serum IgE level of most patients is significantly increased. By introducing monoclonal antibodies into the gene-expression environment of IgE, the levels of free IgE can be effectively suppressed, resulting in a significant reduction in the incidence of AR. Therefore, this article will explore the mechanism and clinical application of this new anti-IgE drug, omalizumab.

CONCLUSION

Omalizumab can significantly relieve the condition of AR patients and reduce the dosage of corticosteroids and antihistamines, but its long-term efficacy and safety need further observation and analysis. Before use, the patient's status should be confirmed and the potential risks should be discussed with the patient in advance.

LuLIPLEX: A Fast, Highly Sensitive, and Multiplexed Method for the Detection of IgE Against Major Allergens

BACKGROUND

Diagnosis of allergies is mostly based on the patient's clinical history and allergen provocation tests. Determination of specific IgE (sIgE) profiles can be performed to support allergy diagnosis. This is commonly done in vivo by the skin prick test or in vitro with automated systems. Several platforms exist to quantify sIgE levels, but all these methods require access to specific instruments, often delaying the test's results. The IgE luciferase-linked immunosorbent assay (LuLISA) allows bioluminescent quantification of IgE against peanut in microliter samples, but this method awaits extension to other allergens. This study aimed to validate a new method, named LuLIPLEX, for multiplexed bioluminescent detection of sIgE against 20 major molecular allergens.

METHODS

Quantification of sIgE against 12 recombinant or purified food allergens and eight aeroallergens was performed by LuLIPLEX versus standard IgE detection methods (ImmunoCAP, ISAC, ALEX, or NOVEOS). Multiplexed detection of IgE against these 20 allergens was performed within 45 min using 50 μL of serum, plasma, or whole blood samples.

RESULTS

A head-to-head comparison between LuLIPLEX and standard IgE detection methods showed a high correlation among all allergens tested. sIgE profiles in polysensitized subjects could be determined within 45 min in serum and plasma samples, as well as using a single drop of capillary blood.

CONCLUSIONS

LuLIPLEX is a rapid and sensitive method to quantify sIgE levels against multiple allergens. Given that the test is very fast and can be performed on small and inexpensive luminometers, the IgE LuLIPLEX could allow point-of-care testing of sIgE profiles in allergic subjects.

Natural killer T cells in allergic asthma: implications for the development of novel immunotherapeutical strategies

Allergic asthma has emerged as a prevalent allergic disease worldwide, affecting most prominently both young individuals and lower-income populations in developing and developed countries. To devise effective and curative immunotherapy, it is crucial to comprehend the intricate nature of this condition, characterized by an immune response imbalance that favors a proinflammatory profile orchestrated by diverse subsets of immune cells. Although the involvement of Natural Killer T (NKT) cells in asthma pathology is frequently implied, their specific contributions to disease onset and progression remain incompletely understood. Given their remarkable ability to modulate the immune response through the rapid secretion of various cytokines, NKT cells represent a promising target for the development of effective immunotherapy against allergic asthma. This review provides a comprehensive summary of the current understanding of NKT cells in the context of allergic asthma, along with novel therapeutic approaches that leverage the functional response of these cells.

Severe asthma ILC2s demonstrate enhanced proliferation that is modified by biologics

BACKGROUND AND OBJECTIVE

Type 2 (T2) innate lymphoid cells (ILC2s) contribute to airway inflammation and disease in asthma. We hypothesize that ILC2s isolated from people with severe allergic and eosinophilic asthma would exhibit an enhanced T2 inflammatory activity that would be altered following treatment with mepolizumab and omalizumab. We compare peripheral blood (PB) isolated ILC2's proliferative capacity, IL-5 and IL-13 secretion and phenotype between healthy without asthma (HC), non-asthma allergic (NAA), mild asthma (MA) and severe allergic and eosinophilic asthma (SA) subjects. We then determined the impact of 6 months treatment with either mepolizumab or omalizumab on ILC2s physiology of SA subjects.

METHODS

ILC2s were sorted and cultured in the presence of IL-2, IL-25, IL-33 and thymic stromal lymphopoietin (TSLP) for 14 days. ILC2s proliferation, phenotypes and functions were assessed using flowcytometry. The ILC2s response was then reassessed following clinically successful treatment of SA subjects with mepolizumab and omalizumab.

RESULTS

SA ILC2s demonstrated increased proliferative capacity, TSLP receptor (TSLPR), GATA3 and NFATc1 protein expressions and increased IL-5 and IL-13 release. ILC2s were also capable of releasing IL-6 in response to stimulation. Mepolizumab treatment reduced ILC2s proliferative capacity and expression of TSLPR, GATA3 and NFATc1. Both mepolizumab and omalizumab were associated with reduced ILC2s release of IL-5 and IL-13, only mepolizumab reduced IL-6.

CONCLUSION

ILC2s from severe allergic and eosinophilic asthma demonstrated an active phenotype typified by increased proliferation, TSLPR, GATA3 and NFATc1 expression and increased IL-5, IL-13 and IL-6 release. Mepolizumab reduced markers of ILC2s activation.

The evolving landscape of immunotherapy for the treatment of allergic conditions

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

Inhaled drug delivery for the targeted treatment of asthma

Asthma is a chronic lung disease affecting millions worldwide. While classically acknowledged to result from allergen-driven type 2 inflammatory responses leading to IgE and cytokine production and the influx of immune cells such as mast cells and eosinophils, the wide range in asthmatic pathobiological subtypes lead to highly variable responses to anti-inflammatory therapies. Thus, there is a need to develop patient-specific therapies capable of addressing the full spectrum of asthmatic lung disease. Moreover, delivery of targeted treatments for asthma directly to the lung may help to maximize therapeutic benefit, but challenges remain in design of effective formulations for the inhaled route. In this review, we discuss the current understanding of asthmatic disease progression as well as genetic and epigenetic disease modifiers associated with asthma severity and exacerbation of disease. We also overview the limitations of clinically available treatments for asthma and discuss pre-clinical models of asthma used to evaluate new therapies. Based on the shortcomings of existing treatments, we highlight recent advances and new approaches to treat asthma via inhalation for monoclonal antibody delivery, mucolytic therapy to target airway mucus hypersecretion and gene therapies to address underlying drivers of disease. Finally, we conclude with discussion on the prospects for an inhaled vaccine to prevent asthma.

Epidemiology, Treatment and Health Care Resource Use of Patients with severe Asthma in Germany – a retrospective Claims Data Analysis

BACKGROUND

Asthma causes various clinical symptoms, including unpredictable severe exacerbations, and even though most patients can achieve a reasonable disease control due to adequate treatment, some patients do not. This study seeks to describe healthcare resource utilization (HCRU) and treatment of asthma and severe asthma patients in Germany.

METHOD

A retrospective claims data analysis has been conducted on adult asthma patients and a subset of patients with severe asthma, identified during July 2017 - June 2018. A proxy was used to identify severe asthma patients based on therapy options recommended within the German treatment guideline for treating these patients. These include (i) biologics, (ii) medium/high-dose inhaled corticosteroids (ICS) in conjunction with LABA/montelukast and antibiotics/oral corticosteroids (OCS), and (iii) long-term OCS therapy. HCRU and treatment of patients were observed during a 1-year follow-up period (July 2018 - June 2019).

RESULTS

The study included 388 932 adult asthma patients (prevalence: 7.90%), with 2.51%-12.88% affected by severe asthma (depending on the definition). 22.60% of all asthma patients experienced hospitalizations (severe asthma: 36.11%). Furthermore, 13.59% received OCS (severe asthma: 39.91%), but only 0.18% (severe asthma: 1.25%) received biologics. Only 23.95% (severe asthma: 41.17%) visited a pulmonologist.

CONCLUSIONS

A considerable proportion of severe asthma patients receive long-term OCS therapy. However, less than 50% have seen a pulmonologist who would typically seek a change in treatment to avoid the long-term consequences of OCS. To optimize the treatment of severe asthma in Germany, better referral of these patients to specialists is needed and considering potential treatment alternatives.

Recent advances in the treatment of childhood asthma: a clinical pharmacology perspective

INTRODUCTION

Childhood asthma is a complex heterogenous inflammatory disease that can pose a large burden on patients and their caregivers. There is a strong need to adapt asthma treatment to the individual patient taking into account underlying inflammatory profiles, moving from a 'one size fits all' approach toward a much-needed personalized approach.

AREAS COVERED

This review article aims to provide an overview of recent advances in the management and treatment of pediatric asthma, including novel insights on the molecular heterogeneity of childhood asthma, the emergence of biologicals to treat severe asthma, and innovative e-health and home monitoring techniques to make asthma management more convenient and accessible.

EXPERT OPINION

Molecular technologies have provided new treatment leads. E-health and home monitoring technologies have helped to gain more insights into disease dynamics and improve adherence to treatment while bringing health care to the patient. However, uncontrolled childhood asthma is still a major unmet clinical need and precision-medicine approaches are still scarce in clinical practice. Advanced omics methods may help researchers or clinicians to more accurately phenotype and treat subtypes of childhood asthma and gain more insight into the complexity of the disease.

Biologic drugs in treating allergic bronchopulmonary aspergillosis in patients with cystic fibrosis: a systematic review

BACKGROUND

Aspergillus fumigatus is a common saprophytic fungus causing allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis (CF). The recommended first-line treatment for ABPA is oral steroids, followed by antifungal therapy. However, both treatments are not free from adverse effects; thus, efforts are being made to identify new drugs showing the same effectiveness but with fewer or no side-effects. Therein, biologic drugs have been significantly implemented in clinical practice in treating ABPA in patients with CF.

OBJECTIVE

To systematically review the available literature, providing evidence for the administration of biologic drugs as a new potential treatment of ABPA in both the paediatric and adult populations with CF.

METHODS

A systematic review of the literature published between January 2007 and July 2021 was performed, using a protocol registered with the International Prospective Register of Systematic Reviews (PROSPERO CRD42021270932).

RESULTS

A total of 21 studies focusing on the use of biologics in treating ABPA in CF patients was included. We highlighted a paucity of data providing evidence for biologic drug use in ABPA.

CONCLUSION

Scientific evidence is insufficient to support firm conclusions and randomised clinical trials are urgently required to investigate the efficacy and safety of biologics for ABPA in CF patients.

A fully human anti-c-Kit monoclonal antibody 2G4 inhibits proliferation and degranulation of human mast cells

Given that mast cells are pivotal contributors to allergic diseases, various allergy treatments have been developed to inhibit them. Omalizumab, an anti-immunoglobulin E antibody, is a representative therapy that can alleviate allergy symptoms by inhibiting mast cell degranulation. However, omalizumab cannot reduce the proliferation and accumulation of mast cells, which is a fundamental cause of allergic diseases. c-Kit is essential for the proliferation, survival, and differentiation of mast cells. Excessive c-Kit activation triggers various mast cell diseases, such as asthma, chronic spontaneous urticaria, and mastocytosis. Herein, we generated 2G4, an anti-c-Kit antibody, to develop a therapeutic agent for mast cell diseases. The therapeutic efficacy of 2G4 antibody was evaluated in LAD2, a human mast cell line. 2G4 antibody completely inhibited c-Kit signaling by blocking the binding of stem cell factor, known as the c-Kit ligand. Inhibition of c-Kit signaling led to the suppression of proliferation, migration, and degranulation in LAD2 cells. Moreover, 2G4 antibody suppressed the secretion of pro-inflammatory cytokines, including granulocyte–macrophage colony-stimulating factor, vascular endothelial growth factor, C–C motif chemokine ligand 2, brain-derived neurotrophic factor, and complement component C5/C5a, which can exacerbate allergy symptoms. Taken together, these results suggest that 2G4 antibody has potential as a novel therapeutic agent for mast cell diseases.

Severe asthma in children: An official statement from Saudi Pediatric Pulmonology Association

In Saudi Arabia, the prevalence of pediatric asthma ranges between 8% and 25%. However, there are no sufficient data regarding severe asthma in childhood in Saudi Arabia. Therefore, a task force has been formed by the Saudi Pediatric Pulmonology Association which is a subsidiary group of the Saudi Thoracic Society and consists of Saudi experts with well-respected academic and clinical backgrounds in the fields of pediatric asthma as well as other respiratory diseases to write a consensus on definitions, phenotypes, and pathophysiology, evaluation, and management. To achieve this, the subject was divided into various sections, each of which was assigned to at least 2 experts. Without a central literature review, the authors searched the literature using their own strategies. To reach an agreement, the entire panel reviewed and voted on proposed findings and recommendations.

Holy Grail: the journey towards disease modification in asthma

At present, there is no cure for asthma, and treatment typically involves therapies that prevent or reduce asthma symptoms, without modifying the underlying disease. A “disease-modifying” treatment can be classed as able to address the pathogenesis of a disease, preventing progression or leading to a long-term reduction in symptoms. Such therapies have been investigated and approved in other indications, e.g. rheumatoid arthritis and immunoglobulin E-mediated allergic disease. Asthma's heterogeneous nature has made the discovery of similar therapies in asthma more difficult, although novel therapies (e.g. biologics) may have the potential to exhibit disease-modifying properties. To investigate the disease-modifying potential of a treatment, study design considerations can be made, including: appropriate end-point selection, length of trial, age of study population (key differences between adults/children in physiology, pathology and drug metabolism) and comorbidities in the patient population. Potential future focus areas for disease-modifying treatments in asthma include early assessments (e.g. to detect patterns of remodelling) and interventions for patients genetically susceptible to asthma, interventions to prevent virally induced asthma and therapies to promote a healthy microbiome. This review explores the pathophysiology of asthma, the disease-modifying potential of current asthma therapies and the direction future research may take to achieve full disease remission or prevention.

Asthma is a complex, heterogeneous disease, which currently has no cure; this review explores the disease-modifying potential of asthma therapies and the direction future research may take to achieve disease remission or prevention.https://bit.ly/31AxYou

Feasibility of plant-expression system for production of recombinant anti-human IgE: An alternative production platform for therapeutic monoclonal antibodies

Omalizumab, the anti-immunoglobulin IgE antibody is the only approved and available monoclonal antibody as an auxiliary medicament for the severe respiratory allergic reactions. It forms small size immune complexes by binding to free IgE, thereby inhibiting the interaction of IgE with its receptors. Additionally, the anti-IgE can also differently shape the airflow by impeding the stimulation of IgE receptors present on structural cells in the respiratory tract. The present study aimed to use plants as an expression system for anti-human IgE antibody production, using Nicotiana benthamiana as hosts. Recombinant Agrobacterium tumefaciens containing heavy chain (HC) and light chain (LC) domains of anti-human IgE were co-transformed in N. benthamiana. The assembling of the antibody and its expression was detected by SDS-PAGE and Western blot analysis. The functional ability of the anti-IgE antibody was determined via its binding capacity with target IgE by ELISA and the inhibition of basophil activation. The anti-human IgE mAb generated in plants was shown to be effective in binding to its target IgE and inhibit the IgE-crosslink in RS-ATL8 reporter cells. Although, antibody yield and purification process have to be further optimized, this study demonstrates the use of plant expression system as a promising platform for the production of Omalizumab which showed a comparable in vitro function to that of commercial Omalizumab (Xolair) in the inhibition of basophil activation.

Type I Interferon Induction and Exhaustion during Viral Infection: Plasmacytoid Dendritic Cells and Emerging COVID-19 Findings

Type I Interferons (IFN-I) are a family of potent antiviral cytokines that act through the direct restriction of viral replication and by enhancing antiviral immunity. However, these powerful cytokines are a caged lion, as excessive and sustained IFN-I production can drive immunopathology during infection, and aberrant IFN-I production is a feature of several types of autoimmunity. As specialized producers of IFN-I plasmacytoid (p), dendritic cells (DCs) can secrete superb quantities and a wide breadth of IFN-I isoforms immediately after infection or stimulation, and are the focus of this review. Notably, a few days after viral infection pDCs tune down their capacity for IFN-I production, producing less cytokines in response to both the ongoing infection and unrelated secondary stimulations. This process, hereby referred to as "pDC exhaustion", favors viral persistence and associates with reduced innate responses and increased susceptibility to secondary opportunistic infections. On the other hand, pDC exhaustion may be a compromise to avoid IFN-I driven immunopathology. In this review we reflect on the mechanisms that initially induce IFN-I and subsequently silence their production by pDCs during a viral infection. While these processes have been long studied across numerous viral infection models, the 2019 coronavirus disease (COVID-19) pandemic has brought their discussion back to the fore, and so we also discuss emerging results related to pDC-IFN-I production in the context of COVID-19.

Targeted therapy in eosinophilic chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a common and preventable airway disease causing significant worldwide mortality and morbidity. Lifetime exposure to tobacco smoking and environmental particles are the two major risk factors. Over recent decades, COPD has become a growing public health problem with an increase in incidence. COPD is defined by airflow limitation due to airway inflammation and small airway remodelling coupled to parenchymal lung destruction. Most patients exhibit neutrophil-predominant airway inflammation combined with an increase in macrophages and CD8⁺ T-cells. Asthma is a heterogeneous chronic inflammatory airway disease. The most studied subtype is type 2 (T2) high eosinophilic asthma, for which there are an increasing number of biologic agents developed. However, both asthma and COPD are complex and share common pathophysiological mechanisms. They are known as overlapping syndromes as approximately 40% of patients with COPD present an eosinophilic airway inflammation. Several studies suggest a putative role of eosinophilia in lung function decline and COPD exacerbation. Recently, pharmacological agents targeting eosinophilic traits in uncontrolled eosinophilic asthma, especially monoclonal antibodies directed against interleukins (IL-5, IL-4, IL-13) or their receptors, have shown promising results. This review examines data on the rationale for such biological agents and assesses efficacy in T2-endotype COPD patients.

Patients with severe COPD and eosinophilic inflammation experience uncontrolled symptoms despite optimal pharmaceutical treatment. The development of new biomarkers is needed for better phenotyping of patients to propose innovative targeted therapy.https://bit.ly/2KzWuNO

Asthma in Cystic Fibrosis: Definitions and Implications of This Overlap Syndrome

PURPOSE OF REVIEW

Cystic fibrosis (CF) is a multisystem, autosomal recessive disease that leads to progressive loss of lung function. Respiratory symptoms for both CF and asthma include cough, wheezing, and dyspnea. There is debate within the CF community on how to best define and distinguish CF-asthma overlap syndrome (CFAOS) from asthma-like features, though CFAOS is well-recognized. We aim to review the epidemiology, diagnosis, and treatment of asthma in CF and explore areas where further research is needed.

RECENT FINDINGS

There has been considerable improvement in the understanding and treatment of asthma over the past two decades leading to novel therapies such as biologic agents that target the airway inflammation in asthmatics based on their asthma phenotype. These therapies are being studied in CFAOS and are promising treatments. This review provides a comprehensive overview of the definition, epidemiology, diagnosis, and current treatment of CFAOS.

Efficacy and safety of omalizumab in children with moderate-to-severe asthma: a meta-analysis

OBJECTIVE

To assess the efficacy and safety of omalizumab in children with moderate-to-severe asthma.Data sources: We systematically searched MEDLINE, EMBASE, and Cochrane for randomized controlled trials (RCTs ) (inception to January 2020).Study selections: All RCTs which were conducted in childhood and adolescence with asthma and compared the efficacy or safety of omalizumab were adopted.

RESULTS

Three studies with four publications including 1380 pediatric patients met our criteria. For children with moderate-to-severe asthma, omalizumab decreased asthma exacerbations rate (OR 0.51, 95% CI: 0.44-0.58, p < 0.001) compared with placebo with no evidence of heterogeneity. Omalizumab reduced the rate of asthma exacerbations 0.58) with treatment period ≥30 weeks (p for heterogeneity = 0.03). Omalizumab treated patients had an excellent or good response rate of treatment effectiveness assessed by physicians (2.75, 2.45-3.09) and a bigger reduction in the dosage of inhaled corticosteroid (ICS) at the end of follow-up. For children with severe asthma, omalizumab also reduced the likelihood of asthma exacerbations and increased the odd of treatment effectiveness rated as excellent or good. Patients receiving omalizumab had a lower incidence of severe adverse events (0.36, 0.22-0.57).

CONCLUSIONS

These findings suggested that omalizumab had beneficial effects on moderate-to-severe asthma in children. Patients may benefit more from long-term use of omalizumab. In addition, omalizumab reduces the rate of serious adverse events requiring hospitalizations.

Infectious Complications of Biological and Small Molecule Targeted Immunomodulatory Therapies

The past 2 decades have seen a revolution in our approach to therapeutic immunosuppression. We have moved from relying on broadly active traditional medications, such as prednisolone or methotrexate, toward more specific agents that often target a single receptor, cytokine, or cell type, using monoclonal antibodies, fusion proteins, or targeted small molecules. This change has transformed the treatment of many conditions, including rheumatoid arthritis, cancers, asthma, and inflammatory bowel disease, but along with the benefits have come risks. Contrary to the hope that these more specific agents would have minimal and predictable infectious sequelae, infectious complications have emerged as a major stumbling block for many of these agents. Furthermore, the growing number and complexity of available biologic agents makes it difficult for clinicians to maintain current knowledge, and most review articles focus on a particular target disease or class of agent. In this article, we review the current state of knowledge about infectious complications of biologic and small molecule immunomodulatory agents, aiming to create a single resource relevant to a broad range of clinicians and researchers. For each of 19 classes of agent, we discuss the mechanism of action, the risk and types of infectious complications, and recommendations for prevention of infection.

Adrenal insufficiency is a contraindication for omalizumab therapy in mast cell activation disease: risk for serum sickness

Omalizumab is an effective therapeutic humanized murine IgE antibody in many cases of primary systemic mast cell activation disease (MCAD). The present study should enable the clinician to recognize when treatment of MCAD with omalizumab is contraindicated because of the potential risk of severe serum sickness and to report our successful therapeutic strategy for such adverse event (AE). Our clinical observations, a review of the literature including the event reports in the FDA AE Reporting System, the European Medicines Agency Eudra-Vigilance databases (preferred search terms: omalizumab, Xolair®, and serum sickness) and information from the manufacturer’s Novartis database were used. Omalizumab therapy may be more likely to cause serum sickness than previously thought. In patients with regular adrenal function, serum sickness can occur after 3 to 10 days which resolves after the antigen and circulating immune complexes are cleared. If the symptoms do not resolve within a week, injection of 20 to 40 mg of prednisolone on two consecutive days could be given. However, in MCAD patients whose adrenal cortical function is completely suppressed by exogenous glucocorticoid therapy, there is a high risk that serum sickness will be masked by the MCAD and evolve in a severe form with pronounced damage of organs and tissues, potentially leading to death. Therefore, before the application of the first omalizumab dose, it is important to ensure that the function of the adrenal cortex is not significantly limited so that any occurring type III allergy can be self-limiting.

Real-World Observational Study on the Characteristics and Treatment Patterns of Allergic Asthma Patients Receiving Omalizumab in Canada

BACKGROUND

Omalizumab is a treatment option for pediatric and adult patients with moderate to severe allergic asthma poorly controlled with standard inhaled therapies. Clinical trials and observational studies have demonstrated the efficacy of omalizumab. There is limited real-world evidence on the characteristics and treatment patterns of Canadian asthma patients receiving omalizumab.

OBJECTIVE

We profiled Canadian omalizumab users to estimate time to omalizumab discontinuation and to assess changes in concurrent medication usage before, during, and after therapy.

METHODS

This was a retrospective, observational, cohort study that analyzed data from Canadian prescription claims databases. An algorithm was used to select naïve users of omalizumab with an inferred diagnosis of GINA 5-asthma who made a claim for omalizumab from February 1, 2007, to June 2, 2015. Demographic and baseline characteristics were assessed at index. Outcomes examined over the analysis period included (i) daily omalizumab dose per patient and per claim; (ii) omalizumab discontinuation (defined as ≥100-day gap in making omalizumab claims) and its potential predictors (ie, age, sex, province of residence, drug insurer; assessed by Cox Proportional Hazards Model); and (iii) for patients who discontinued omalizumab, changes in concurrent medication usage before, during, and 6 months after omalizumab usage.

RESULTS

The final study cohort consisted of 1160 patients (mean age: 45.8 ± 15.2 years; 64.7% female). During the first year of omalizumab therapy, 29.5% of patients discontinued treatment. The singular characteristic that predicted omalizumab discontinuation with statistical significance was age group (20‒34 years vs 12‒19 years; hazard ratio 1.75, 95% confidence interval 1.11-2.76; P<0.05). There were significant reductions in the use of some concurrent inhaled and oral asthma medications during and/or after omalizumab use (P<0.05).

CONCLUSION

Nearly one-third of patients who initiated omalizumab in Canada for refractory, moderate to severe allergic asthma discontinued treatment during the first year.

Intersection of biology and therapeutics: type 2 targeted therapeutics for adult asthma

Asthma is a disease of reversible airflow obstruction characterised clinically by wheezing, shortness of breath, and coughing. Increases in airway type 2 cytokine activity, including interleukin-4 (IL-4), IL-5, and IL-13, are now established biological mechanisms in asthma. Inhaled corticosteroids have been the foundation for asthma treatment, in a large part because they decrease airway type 2 inflammation. However, inhaled or systemic corticosteroids are ineffective treatments in many patients with asthma and few treatment options exist for patients with steroid resistant asthma. Although mechanisms for corticosteroid refractory asthma are likely to be numerous, the development of a new class of biologic agents that target airway type 2 inflammation has provided a new model for treating some patients with corticosteroid refractory asthma. The objective of this Therapeutic paper is to summarise the new type 2 therapeutics, with an emphasis on the biological rationale and clinical efficacy of this new class of asthma therapeutics.

Toward clinically applicable biomarkers for asthma: An EAACI position paper

Inflammation, structural, and functional abnormalities within the airways are key features of asthma. Although these processes are well documented, their expression varies across the heterogeneous spectrum of asthma. Type 2 inflammatory responses are characterized by increased levels of eosinophils, FeNO, and type 2 cytokines in blood and/or airways. Presently, type 2 asthma is the best-defined endotype, typically found in patients with allergic asthma, but surprisingly also in nonallergic patients with (severe) asthma. The etiology of asthma with non-type 2 inflammation is less clear. During the past decade, targeted therapies, including biologicals and small molecules, have been increasingly integrated into treatment strategies of severe asthma. These treatments block specific inflammatory pathways or single mediators. Single or composite biomarkers help to identify patients who will benefit from these treatments. So far, only a few inflammatory biomarkers have been validated for clinical application. The European Academy of Allergy & Clinical Immunology Task Force on Biomarkers in Asthma was initiated to review different biomarker sampling methods and to investigate clinical applicability of new and existing inflammatory biomarkers (point-of-care) to support diagnosis, targeted treatment, and monitoring of severe asthma. Subsequently, we discuss existing and novel targeted therapies for asthma as well as applicable biomarkers.

Combination of immunotherapies for severe allergic asthma

INTRODUCTION

Difficult-to-treat or severe persistent asthma accounts for 5-10% of the asthma population worldwide. However, this group of patients creates a higher burden on health systems due to their morbidity and need for long-term and additional treatment. Biological drugs constitute an alternative therapy in the treatment of patients with refractory asthma. In cases where inhalant allergy is part of the pathomechanism, allergen-specific immunotherapy (SIT) is a causative treatment option for allergic asthma. However, SIT is contraindicated for uncontrolled asthma and cannot be administered according to the guidelines. This is due to the risk of further worsening of uncontrolled asthma during treatment.

CASE STUDY

We herein report a case of a 67-year-old male with severe allergic asthma who was successfully treated with SIT after asthma control was achieved by using target treatments.

RESULTS

Complete control of asthma was achieved, and SIT with allergens from early flowering trees (birch-alder-hazel) was administered. Further, no asthmatic exacerbations or decrease in respiratory function occurred during the 15 months of treatment with mepoluzimab. He did not need any oral glucocorticosteroids.

CONCLUSION

The case report presented here suggests the effectiveness of an individualized approach and phenotype-specific treatment of patients who cannot receive allergen-specific immunotherapy due to the contraindication uncontrolled asthma and who receive SIT after asthma control is achieved by using target treatments.

Monoclonal antibodies for severe asthma: Pharmacokinetic profiles

Several monoclonal antibodies (mAbs) (omalizumab, mepolizumab, reslizumab, benralizumab, and dupilumab) are currently approved for the treatment of severe asthma. They have complex pharmacokinetic profiles. These profiles are unique in that they are dependent on their structure as well as can be markedly influenced by the biology of their target antigen, but their general behaviour can still be considered a class property, similar to their endogenous IgG counterpart. They cannot be administered by oral route, have a slow distribution into tissue, are metabolized to peptides and amino acids in several tissues but are protected from degradation by binding to protective receptors (the FcRn), which explains their long elimination half-lives. Their clearance is nonlinear because of the saturation of the target-mediated elimination. Also anti-drug antibody (ADA) response and off-target binding, as well as their glycosylation pattern, can influence the pharmacokinetics of mAbs.

Asthma in the Primary Care Setting

Asthma is one of the commonest respiratory diseases in the United States, affecting approximately 8% of adults. This article reviews the epidemiology, diagnosis, and treatment of asthma, with integration of recommendations from professional societies, with special attention to differential diagnosis. A framework for outpatient management of patients with asthma is presented, including indications for subspecialist referral. With integration of objective diagnostic information, systematic approach through modification of disease triggers and adjustment of controller medications, and patient empowerment to respond to varying symptoms using an asthma action plan, most individuals with asthma are successfully managed in the primary care setting.

The New Paradigms in Clinical Research: From Early Access Programs to the Novel Therapeutic Approaches for Unmet Medical Needs

Despite several innovative medicines gaining worldwide approval in recent years, there are still therapeutic areas for which unsatisfied therapeutic needs persist. For example, high unmet clinical need was observed in patients diagnosed with type 2 diabetes mellitus and hemophilia, as well as in specific age groups, such as the pediatric population. Given the urgent need to improve the therapy of clinical conditions for which unmet clinical need is established, clinical testing, and approval of new medicines are increasingly being carried out through accelerated authorization procedures. Starting from 1992, the Food and Drug Administration and the European Medicines Agency have supported the so-called Early Access Programs (EAPs). Such procedures, which can be based on incomplete clinical data, allow an accelerated marketing authorization for innovative medicines. The growth in pharmaceutical research has also resulted in the development of novel therapeutic approaches, such as biotech drugs and advanced therapy medicinal products, including new monoclonal antibodies for the treatment of asthma, antisense oligonucleotides for the treatment of Duchenne muscular dystrophy and spinal muscular atrophy, and new anticancer drugs that act on genetic biomarkers rather than any specific type of cancer. Even though EAPs and novel therapeutic approaches have brought huge benefits for public health, their implementation is limited by several challenges, including the high risk of safety-related label changes for medicines authorized through the accelerated procedure, the high costs, and the reimbursement and access concerns. In this context, regulatory agencies should provide the best conditions for the implementation of the described new tools.

Small, Prospective, Observational, Pilot Study in Patients with Severe Asthma after Discontinuation of Omalizumab Treatment

PURPOSE

Omalizumab has demonstrated clinical efficacy in severe allergic asthma by reducing exacerbation rates and increasing quality of life. However, data concerning its sustained effect after treatment discontinuation are still needed.

METHODS

This analysis was an observational pilot study (simple within-subjects design) of 12 patients experiencing severe asthma, treated with omalizumab, for 1 year after treatment discontinuation. We prospectively analyzed clinical measurements (pulmonary functions, inhaled corticosteroid [ICS] doses, Asthma Control Test [ACT] scores, skin prick test [SPT] positivity, fraction of exhaled nitric oxide, and exacerbation rates) and laboratory test results (eosinophils and total immunoglobulin E levels) at the time of discontinuation and 6 and 12 months thereafter. Baseline data (before the treatment period; range, 11-61 months) were collected retrospectively. The treatment effect until discontinuation was calculated. To determine its persistence, repeated measures were compared with baseline levels and analyzed by using a general linear model for repeated measures or the Friedman ANOVA, and χ² tests in case of normality assumption violation or frequencies. Post hoc analysis was applied by using a simple or repeated contrasts analysis or Wilcoxon signed rank test with Bonferroni correction.

FINDINGS

We proved a significant reduction in ICS doses and SPT reactivity and an increase in ACT score during the retrospective treatment phase. Moreover, persistence of these statistically significant effects was recorded 6 months after treatment discontinuation. ACT score and ICS doses (but not SPT reactivity) remained improved for 12 months after discontinuation of omalizumab treatment.

IMPLICATIONS

Omalizumab treatment exhibited sustained treatment benefit after its discontinuation for patients experiencing severe allergic asthma.

Anti-IgE therapy for asthma: an audit at atertiary care centre in Saudi Arabia

BACKGROUND

Although anti-IgE therapy has been shown to offer numerous benefits, we suspect it is underutilized locally. To date, there are no studies on any aspect of its use in the Arab region. There is also no information on whether physicians follow current guidelines nor on patient response to this form of therapy.

OBJECTIVE

Assess the use of omalizumab for patients with difficult asthma at a tertiary care center.

DESIGN

Retrospective, descriptive.

SETTING

Tertiary care hospital.

PATIENTS AND METHODS

Information was collected from medical records and interviews of all patients who received a minimum of 6 months of omalizumab, including data on practices of the prescribing physician (pulmonary versus allergy), indications, dose, subjective response, number of emergency room visits and hospitalizations, changes in asthma medications, adverse effects, and the setting for delivery of therapy.

MAIN OUTCOME MEASURES

Extent to which current guidelines for prescribing omalizumab were followed. Patient subjective and objective responses to treatment as reflected by changes in the use of medications and lung function before and after therapy.

SAMPLE SIZE

50 patients.

RESULTS

Of the 50 consecutive patients, 35 were female and the mean (SD) age was 46.3 (9.2) years. Only 28 patients (56 %) met all the criteria for the prescription of omalizumab as per current guidelines; 18 (64%) by pulmonary and 10 (36%) by allergy physicians (P less than .05). Pulmonary physicians performed more tests for conditions complicating or simulating asthma (P less than .05). The mean (SD) duration of treatment by omalizumab of 35 (22) months was longer in patients managed by allergists (42 [24] months) than pulmonary physicians (30 [21] months) (P greater than .05). Both physician groups prescribed a lower initial dose than recommended (P less than .05 recommended vs. prescribed). Patients reported a significant improvement in symptoms, reduction in the use of broncho-dilators and oral steroids and in the use of healthcare services (from 16.28 [7.9] to 2.08 [1.78], P less than .0001) mean values from sum of hospitalizations/year, ER visits/year, exacerbations/year, but not in other medications or pulmonary function tests (P greater than .05).

CONCLUSION

Despite several benefits, notably a reduction in utilization of health services and asthma medication, anti-IgE therapy is probably underutilized locally. Pulmonary physicians are more likely to follow the guidelines than allergy physicians. This study suggests that there is room for improvement in the prescription practices, particularly in dosing and the setting for delivery. Further multicenter prospective studies are required to identify gaps in the current practices and improve asthma management.

LIMITATIONS

Too few patients met inclusion criteria, lack of control group, and use of a subjective assessment for patient symptoms as opposed to validated questionnaires.

CONFLICT OF INTEREST

None.

Role of biologics targeting type 2 airway inflammation in asthma: what have we learned so far?

PURPOSE OF REVIEW

Severe asthma is a heterogeneous syndrome that can be classified into distinct phenotypes and endotypes. In the type 2 (T2)-high endotype, multiple cytokines are produced that lead to eosinophilic inflammation. These cytokines and their receptors are targets for biologic therapies in patients with severe asthma who do not respond well to standard therapy with inhaled corticosteroids.

RECENT FINDINGS

In the last decade, an increasing number of biologic therapies have been developed targeting T2 inflammation. Clinical trials of therapies targeting immunoglobulin E as well as the T2 cytokines interleukin (IL)-4, IL-5, and IL-13 have demonstrated that these treatments improve asthma-related clinical outcomes and/or have steroid-sparing properties. The use of biomarkers of T2 inflammation can help to identify the subset of patients in whom these therapies may be most efficacious. Multiple biologic agents that are directed at other targets are currently in development, including thymic stromal lymphopoietin (TSLP), prostaglandin (PG)D2 receptor, IL-25, and IL-33.

SUMMARY

Biologics are emerging as a key component of severe asthma management. In patients with T2-high severe asthma, the addition of treatments targeting immunoglobulin E and IL-5 to standard therapy may lead to improvement in clinical outcomes. Other biologic therapies have shown promising preliminary results and need to be studied in further clinical trials. These biologic therapies in conjunction with biomarkers will lead to tailored therapy for asthma.

"Real-life" Efficacy and Safety Aspects of 4-Year Omalizumab Treatment for Asthma

OBJECTIVE

To evaluate the long-term efficacy and safety of omalizumab in asthma in a real-life setting.

SUBJECTS AND METHODS

This 4-year observational study included 65 patients treated with omalizumab during clinic visits; treatment response was rated as excellent, good, and partial based on a modified physician's Global Evaluation of Treatment Effectiveness (mGETE) scale of emergency room visits (ERV), hospitalization, use of oral corticosteroids, inhaled corticosteroid (ICS)/long-acting β-agonist (LABA) dose, and short-acting β-agonist rescue. The following tests were done: forced expiratory volume in 1 s (FEV1) and the asthma control test (ACT). Measurements were performed 1 month before therapy and at 16 weeks, 1 year, and 4 years of treatment. Statistical analyses were done using the Wilcoxon signed-rank test, Spearman rank correlation, and McNemar χ2 test.

RESULTS

The dropout rate was 15 (18.5%): 8 nonresponders (10.0%); 2 patients died (2.5%), and 5 were lost to follow-up (6.25%). Treatment response was excellent in 35 (53.8%); good in 23 (35.4%), and partial in 7 patients (10.8%). The number of excellent responders increased from 35 (53.8%) at 16 weeks to 48 (73.8%) at the 4-year follow-up. The number of patients who did not require ERV improved from 0 to 59 (90.8%), and the lowest rate of hospitalization was 1 in year 4 (p < 0.001); patients who did not require courses of oral corticosteroids improved from 0 to 54 (83%). ICS/LABA dose significantly reduced from 65 (100%) to 25 (38.5%) after 4 years of treatment (p < 0.001); ACT scores significantly increased from 15 ± 3 at baseline to 23 ± 3 (p < 0.001) and FEV1 level from 55.6 ± 10.6 to 76.63 ± 10.34 at year 4.

CONCLUSION

In this study, omalizumab therapy resulted in better asthma control, and was effective and well tolerated as an add-on therapy for patients with moderate-to-severe asthma.

Risk and safety requirements for diagnostic and therapeutic procedures in allergology: World Allergy Organization Statement

One of the major concerns in the practice of allergy is related to the safety of procedures for the diagnosis and treatment of allergic disease. Management (diagnosis and treatment) of hypersensitivity disorders involves often intentional exposure to potentially allergenic substances (during skin testing), deliberate induction in the office of allergic symptoms to offending compounds (provocation tests) or intentional application of potentially dangerous substances (allergy vaccine) to sensitized patients. These situations may be associated with a significant risk of unwanted, excessive or even dangerous reactions, which in many instances cannot be completely avoided. However, adverse reactions can be minimized or even avoided if a physician is fully aware of potential risk and is prepared to appropriately handle the situation. Information on the risk of diagnostic and therapeutic procedures in allergic diseases has been accumulated in the medical literature for decades; however, except for allergen specific immunotherapy, it has never been presented in a systematic fashion. Up to now no single document addressed the risk of the most commonly used medical procedures in the allergy office nor attempted to present general requirements necessary to assure the safety of these procedures. Following review of available literature a group of allergy experts within the World Allergy Organization (WAO), representing various continents and areas of allergy expertise, presents this report on risk associated with diagnostic and therapeutic procedures in allergology and proposes a consensus on safety requirements for performing procedures in allergy offices. Optimal safety measures including appropriate location, type and required time of supervision, availability of safety equipment, access to specialized emergency services, etc. for various procedures have been recommended. This document should be useful for allergists with already established practices and experience as well as to other specialists taking care of patients with allergies.

Impact of omalizumab on treatment of severe allergic asthma in UK clinical practice: a UK multicentre observational study (the APEX II study)

OBJECTIVE

To describe the impact of omalizumab on asthma management in patients treated as part of normal clinical practice in the UK National Health Service (NHS).

DESIGN

A non-interventional, mixed methodology study, combining retrospective and prospective data collection for 12 months pre-omalizumab and post-omalizumab initiation, respectively.

SETTING

Data were collected in 22 UK NHS centres, including specialist centres and district general hospitals in the UK.

PARTICIPANTS

258 adult patients (aged ≥16 years; 65% women) with severe persistent allergic asthma treated with omalizumab were recruited, of whom 218 (84.5%) completed the study.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was change in mean daily dose of oral corticosteroids (OCS) between the 12-month pre-omalizumab and post-omalizumab initiation periods. A priori secondary outcome measures included response to treatment, changes in OCS dosing, asthma exacerbations, lung function, employment/education, patient-reported outcomes and hospital resource utilisation.

RESULTS

The response rate to omalizumab at 16 weeks was 82.4%. Comparing pre-omalizumab and post-omalizumab periods, the mean (95% CIs) daily dose of OCS decreased by 1.61 (-2.41 to -0.80) mg/patient/day (p<0.001) and hospital exacerbations decreased by 0.97 (-1.19 to -0.75) exacerbations/patient (p<0.001). Compared with baseline, lung function, assessed by percentage of forced expiratory volume in 1 s, improved by 4.5 (2.7 to 6.3)% at 16 weeks (p<0.001; maintained at 12 months) and patient quality of life (Asthma Quality of Life Questionnaire) improved by 1.38 (1.18 to 1.58) points at 16 weeks (p<0.001, maintained at 12 months). 21/162 patients with complete employment data gained employment and 6 patients lost employment in the 12-month post-omalizumab period. The mean number of A&E visits, inpatient hospitalisations, outpatient visits (excluding for omalizumab) and number of bed days/patient decreased significantly (p<0.001) in the 12-month post-omalizumab period.

CONCLUSIONS

These data support the beneficial effects of omalizumab on asthma-related outcomes, quality of life and resource utilisation in unselected patients treated in 'real-world' clinical practice.

Systematic review on the use of omalizumab for the treatment of asthmatic children and adolescents

BACKGROUND

There are less data on omalizumab treatment in pediatric asthma than in adult population. Thus, to establish the efficacy and safety of subcutaneous omalizumab as an add-on therapy, a systematic review of placebo-controlled studies was performed.

METHODS

Primary outcome was the frequency of asthma exacerbations. Secondary outcomes included spirometric measures, rescue medication use, asthma symptoms, health-related quality of life, and adverse events.

RESULTS

Three randomized controlled trials (1381 participants) fulfilled the selection criteria. During the stable phase, omalizumab decreased the number of patients with at least one significant asthma exacerbation (26.7% vs. 40.6%, NNTB = 7, 95% CI, 5, 11). The predefined post hoc subgroup analysis showed that duration of treatment did not influence this result. During the steroid reduction phase, omalizumab reduced the number of patients with at least one exacerbation (RR = 0.48, 95% CI, 0.38, 0.61; NNTB = 6, 95% CI, 4, 8) and also the mean number of asthma exacerbations per patient (MD = -0.44, 95% CI, -0.72, -0.17) when compared to placebo. The frequency of serious adverse events was similar between omalizumab (5.2%) and placebo (5.6%), and there were no evidence of increased risk of hypersensitivity reactions, nor malignant neoplasms.

CONCLUSIONS

Data indicate that the efficacy of an add-on omalizumab in patients with moderate-to-severe allergic asthma uncontrolled with recommended inhaled steroid treatment is accompanied by an acceptable safety profile.

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.

Monoclonal antibodies for the treatment of refractory asthma

PURPOSE OF REVIEW

A small proportion of patients with asthma have severe disease characterized by persistent airflow obstruction, airway hyperresponsiveness and eosinophilic airway inflammation. This review focuses on the clinical efficacy of inhibiting T helper 2-cytokine-mediated inflammatory responses using monoclonal antibodies directed against immunoglobulin E (IgE), interleukin (IL)-5, and IL-4/IL-13 in patients with severe refractory asthma.

RECENT FINDINGS

The heterogeneity of airway inflammation in severe asthma has led to the recognition of multiple pathophysiologically distinct severe asthma endotypes. Biomarkers are being developed and evaluated to identify these endotypes and to guide the use of specific biologics in the appropriate patients who remain uncontrolled on high doses of inhaled corticosteroids and long-acting bronchodilators or oral corticosteroids. Examples include the efficacy of omalizumab in patients with severe refractory atopic asthma characterized by raised serum total IgE, mepolizumab, reslizumab, and benralizumab in patients with recurrent eosinophilic exacerbations characterized by blood and sputum eosinophilia despite high doses of corticosteroids, and lebrikizumab, pitrakinra, dupilumab, and tralokinumab that target the IL-4/IL-13 signalling pathways in patients with eosinophilic asthma or raised serum periostin.

SUMMARY

In severe refractory asthma, both an understanding of the underlying pathophysiologic mechanisms driving airway inflammation and the identification of appropriate biomarkers in individual patients are critical in guiding the use of biologics and monoclonal antibodies that target the specific pathological processes.

The bee sting that was not: an unusual case of hymenoptera anaphylaxis averted in a patient treated with omalizumab for asthma

This paper presents a case of hymenoptera venom anaphylaxis averted by omalizumab, a monoclonal antibody to IgE antibody. This case suggests a novel and unintentional effect of this therapy. Currently omalizumab is only FDA approved for the treatment of moderate-persistent allergic asthma. However case reports, such as ours have illustrated omalizumab's efficacy in the treatment of a myriad immunologic and allergic diseases. These outcomes have broadened the understanding of omalizumab's complex mechanism of action.

Omalizumab in asthma: an update on recent developments

IgE is central to the pathophysiology of allergic asthma. Omalizumab, a humanized anti-IgE mAb, specifically binds free IgE and interrupts the allergic cascade by preventing binding of IgE with its high-affinity FcεRI receptors on mast cells, antigen-presenting cells, and other inflammatory cells. The clinical efficacy of omalizumab has been well documented in a number of clinical trials that involve adults, adolescents, and children with moderate-to-severe and severe allergic asthma. In these studies, omalizumab reduced exacerbations, asthma symptoms, inhaled corticosteroid and rescue medication use, and improved quality of life relative to placebo or best standard of care. Similar benefits have been reported in observational studies in "real-world" populations of patients. Results from recent pooled data from randomized clinical trials and from a large prospective cohort study provide reassurance about the long-term safety of omalizumab. Omalizumab dosing is individualized according to body weight and serum-IgE level, and recent adjustments to the dosing algorithm in Europe have enabled more patients to be eligible for treatment. Ongoing and future research is investigating the optimal duration of therapy, accurate predictors of response to treatment, and efficacy in nonatopic asthma as well as other IgE-mediated conditions.

Omalizumab in an allergology clinic: real life experience and future developments

Omalizumab is a recombinant humanized monoclonal antibody that reduces levels of circulating IgE and expression of IgE high affinity receptor (FCɛRI) on mast cells and basophils. Its role in the therapy of allergic asthma and urticaria is well established. According to GINA guidelines, omalizumab should be considered as an important alternative to systemic corticosteroids in uncontrolled asthma. Several ongoing trials will evaluate omalizumab efficacy in the treatment of other allergic diseases and conditions. Further studies are needed to answer several practical questions on the optimal duration of treatment and possible biomarkers to predefine a cohort of responders to this therapy.

Omalizumab as a new therapeutic approach for children with severe asthma

Omalizumab has been shown to improve asthma control when added to a regimen of guideline-based therapy for inner-city children and adolescents, nearly eliminating seasonal peaks in exacerbation and reducing the need for other medications to control asthma. Below, we describe a case of a 17-year-old non-smoker with a history of severe asthma admitted to our clinic after unsuccessful 10-year immunotherapy. The patient fulfilled the criteria for anti-IgE therapy, he was prescribed omalizumab 600 mg every 2 weeks. During therapy he was able to reduce his use of ICS and did not require any oral corticosteroids. He experienced an increase in his ability to exercise and noted no exacerbation of asthma symptoms. It is possible that in our patient, specific immunotherapy could be successfully continued after the initiation of omalizumab therapy.

Omalizumab for asthma in adults and children

BACKGROUND

Asthma is a respiratory (airway) condition that affects an estimated 300 million people worldwide and is associated with significant morbidity and mortality. Omalizumab is a monoclonal antibody that binds and inhibits free serum immunoglobulin E (IgE). It is called an 'anti-IgE' drug. IgE is an immune mediator involved in clinical manifestations of asthma. A recent update of National Institute for Health and Care Excellence (NICE) guidance in 2013 recommends omalizumab for use as add-on therapy in adults and children over six years of age with inadequately controlled severe persistent allergic IgE-mediated asthma who require continuous or frequent treatment with oral corticosteroids.

OBJECTIVES

To assess the effects of omalizumab versus placebo or conventional therapy for asthma in adults and children.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register of trials for potentially relevant studies. The most recent search was performed in June 2013. We also checked the reference lists of included trials and searched online trial registries and drug company websites.

SELECTION CRITERIA

Randomised controlled trials examining anti-IgE administered in any manner for any duration. Trials with co-interventions were included, as long as they were the same in each arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted and entered data. Three modes of administration were identified from the published literature: inhaled, intravenous and subcutaneous injection. The main focus of the updated review is subcutaneous administration, as this route is currently used in clinical practice. Subgroup analysis was performed by asthma severity. Data were extracted from published and unpublished sources.

MAIN RESULTS

In all, 25 trials were included in the review, including 11 new studies since the last update, for a total of 19 that considered the efficacy of subcutaneous anti-IgE treatment as an adjunct to treatment with corticosteroids.For participants with moderate or severe asthma who were receiving background inhaled corticosteroid steroid (ICS) therapy, a significant advantage favoured subcutaneous omalizumab with regard to experiencing an asthma exacerbation (odds ratio (OR) 0.55, 95% confidence interval (CI) 0.42 to 0.60; ten studies, 3261 participants). This represents an absolute reduction from 26% for participants suffering an exacerbation on placebo to 16% on omalizumab, over 16 to 60 weeks. A significant benefit was noted for subcutaneous omalizumab versus placebo with regard to reducing hospitalisations (OR 0.16, 95% CI 0.06 to 0.42; four studies, 1824 participants), representing an absolute reduction in risk from 3% with placebo to 0.5% with omalizumab over 28 to 60 weeks. No separate data on hospitalisations were available for the severe asthma subgroup, and all of these data were reported for participants with the diagnosis of moderate to severe asthma. Participants treated with subcutaneous omalizumab were also significantly more likely to be able to withdraw their ICS completely than those treated with placebo (OR 2.50, 95% CI 2.00 to 3.13), and a small but statistically significant reduction in daily inhaled steroid dose was reported for omalizumab-treated participants compared with those given placebo (weighted mean difference (WMD) -118 mcg beclomethasone dipropionate (BDP) equivalent per day, 95% CI -154 to -84). However, no significant difference between omalizumab and placebo treatment groups was seen in the number of participants who were able to withdraw from oral corticosteroid (OCS) therapy (OR 1.18, 95% CI 0.53 to 2.63).Participants treated with subcutaneous omalizumab as an adjunct to treatment with corticosteroids required a small but significant reduction in rescue beta2-agonist medication compared with placebo (mean difference (MD) -0.39 puffs per day, 95% CI -0.55 to -0.24; nine studies, 3524 participants). This benefit was observed in both the moderate to severe (MD -0.58, 95% CI -0.84 to -0.31) and severe (MD -0.30, 95% CI -0.49 to -0.10) asthma subgroups on a background therapy of inhaled corticosteroids; however, no significant difference between subcutaneous omalizumab and placebo was noted for this outcome in participants with severe asthma who were receiving a background therapy of inhaled plus oral corticosteroids. Significantly fewer serious adverse events were reported in participants assigned to subcutaneous omalizumab than in those receiving placebo (OR 0.72, 95% CI 0.57 to 0.91; 15 studies, 5713 participants), but more injection site reactions were observed (from 5.6% with placebo to 9.1% with omalizumab).To reflect current clinical practice, discussion of the results is limited to subcutaneous use, and trials involving intravenous and inhaled routes have been archived.

AUTHORS' CONCLUSIONS

Omalizumab was effective in reducing asthma exacerbations and hospitalisations as an adjunctive therapy to inhaled steroids and during steroid tapering phases of clinical trials. Omalizumab was significantly more effective than placebo in increasing the numbers of participants who were able to reduce or withdraw their inhaled steroids. Omalizumab was generally well tolerated, although more injection site reactions were seen with omalizumab. Further assessment in paediatric populations is necessary, as is direct double-dummy comparison with ICS. Although subgroup analyses suggest that participants receiving prednisolone had better asthma control when they received omalizumab, it remains to be tested prospectively whether the addition of omalizumab has a prednisolone-sparing effect. It is also not clear whether there is a threshold level of baseline serum IgE for optimum efficacy of omalizumab. Given the high cost of the drug, identification of biomarkers predictive of response is of major importance for future research.

Th2 cytokine antagonists: potential treatments for severe asthma

INTRODUCTION

Asthma is a major disease burden worldwide. Treatment with steroids and long acting β-agonists effectively manage symptoms in many patients but do not treat the underlying cause of disease and have serious side effects when used long term and in children. Therapies targeting the underlying causes of asthma are urgently needed. T helper type 2 (Th2) cells and the cytokines they release are clinically linked to the presentation of all forms of asthma. They are the primary drivers of mild to moderate and allergic asthma. They also play a pathogenetic role in exacerbations and more severe asthma though other factors are also involved. Much effort using animal models and human studies has been dedicated to the identification of the pathogenetic roles of these cells and cytokines and whether inhibition of their activity has therapeutic benefit in asthma.

AREAS COVERED

We discuss the current status of Th2 cytokine antagonists for the treatment of asthma. We also discuss the potential for targeting Th2-inducing cytokines, Th2 cell receptors and signaling as well as the use of Th2 cell antagonists, small interfering oligonucleotides, microRNAs, and combination therapies.

EXPERT OPINION

Th2 antagonists may be most effective in particular asthma subtypes/endotypes where specific cytokines are known to be active through the analysis of biomarkers. Targeting common receptors and pathways used by these cytokines may have additional benefit. Animal models have been valuable in identifying therapeutic targets in asthma, however the results from such studies need to be carefully interpreted and applied to appropriately stratified patient cohorts in well-designed clinical studies and trials.

Lebrikizumab in the personalized management of asthma

There is a need for improved therapies for severe asthma. Lebrikizumab, a humanized monoclonal antibody that binds to interleukin (IL)-13, is under development for the treatment of poorly controlled asthma. This article reviews the potential role of IL-13 in the pathogenesis of asthma, the efficacy and safety of lebrikizumab in humans, and progress in patient selection for lebrikizumab therapy. IL-13 is a T-helper (Th2) cell-derived cytokine implicated in inflammatory responses in asthma, including serum immunoglobulin-E synthesis, mucus hypersecretion, and subepithelial fibrosis. Blocking the pro-inflammatory effects of IL-13 with lebrikizumab has the potential to improve asthma control. Published data on the efficacy and safety of lebrikizumab in the treatment of asthma are relatively limited. The late asthmatic response after inhaled allergen challenge is reduced by almost 50%, following treatment with lebrikizumab. In a Phase II study performed in 219 adults with poorly controlled asthma despite inhaled corticosteroids (MILLY trial), lebrikizumab produced an improvement in prebronchodilator forced expiratory volume in 1 second of 5.5% compared with placebo at 12 weeks, but had no effects on other efficacy end points. Adverse effects were similar to placebo, except that musculoskeletal side effects occurred slightly more often with lebrikizumab. Stratifying patients into a high Th2 phenotype using serum periostin, which is upregulated in lung epithelial cells by IL-13, may identify individuals responsive to blockade of IL-13. In the MILLY trial, lebrikizumab treatment was associated with greater improvement in lung function in patients with elevated serum periostin levels compared with those with low periostin levels. Two large Phase III randomized controlled trials in patients with uncontrolled asthma are underway to establish the safety and efficacy of lebrikizumab when administered over a 52-week period. These studies will also help to determine whether identifying patients with a Th2 high inflammatory phenotype using serum periostin allows a personalized approach to the treatment of asthma.