The effect of intravenous administration of a chimeric anti-IgE antibody on serum IgE levels in atopic subjects: efficacy, safety, and pharmacokinetics

Long-term IgE immunological tolerance to peanut allergens: An alternative to Noon's daily desensitization paradigm

Herein, we show that profound afferent long-term peanut-allergen-specific IgE immunological tolerance for 3 to 9 months induced sustained unresponsiveness (SU) in naïve or peanut-sensitized rodents after peanut allergen immunization. Rodents were vaccinated sublingually with a peanut allergen extract or recombinant peanut allergen in chenodeoxycholate (CDCA), a fanesoid X receptor (FXR, NR1H4) agonist that downregulates SREBP-1c (sterol regulatory element binding protein-1c) and upregulates SHP in bone marrow-derived tolerogenic dendritic cells (DCs). Approximately 90 ∼ 95 % of the total circulating PE-potentiated IgE and Ara h1, Ara h 2, and Ara h 6 peanut allergen-specific IgE responses were suppressed by recombinant peanut allergen-conjugated solid magnetic beads (sensitivity of 0.2 IU/ml). In contrast, peanut allergen-specific IgG production was not affected. Similarly, oleoylethanolamine (OEA), a peroxisome proliferator-activator receptor alpha (PPARα) agonist, and GW9662, a PPARγ antagonist, induced long-term peanut-specific IgE tolerance when administered via the sublingual, oral or i.p. route. Prophylactic Ara h2 DNA immunization with caNRF2 and IL-35 coexpression induced Ara h2 IgE tolerance. In summary, peanut allergen vaccination with select natural molecular ligands of nuclear receptors induced long-term peanut allergen-specific IgE tolerance via the afferent limb, which indicates that vaccination is an immune tolerance-promoting strategy that is effective at the DC level and that differs from Noon's daily desensitization program, which is effective at the mast cell level.

Biologics in Asthma: A Molecular Perspective to Precision Medicine

Recent developments in therapeutic strategies have provided alternatives to corticosteroids as the cornerstone treatment for managing airway inflammation in asthma. The past two decades have witnessed a tremendous boost in the development of anti-cytokine monoclonal antibody (mAb) therapies for the management of severe asthma. Novel biologics that target eosinophilic inflammation (or type 2, T2 inflammation) have been the most successful at treating asthma symptoms, though there are a few in the drug development pipeline for treating non-eosinophilic or T2-low asthma. There has been significant improvement in clinical outcomes for asthmatics treated with currently available monoclonal antibodies (mAbs), including anti-immunoglobulin (Ig) E, anti-interleukin (IL)-4 receptor α subunit, anti-IL-5, anti-IL-5Rα, anti-IL-6, anti-IL-33, and anti-thymic stromal lymphopoietin (TSLP). Despite these initiatives in precision medicine for asthma therapy, a significant disease burden remains, as evident from modest reduction of exacerbation rates, i.e., approximately 40-60%. There are numerous studies that highlight predictors of good responses to these biologics, but few have focused on those who fail to respond adequately despite targeted treatment. Phenotyping asthmatics based on blood eosinophils is proving to be inadequate for choosing the right drug for the right patient. It is therefore pertinent to understand the underlying immunology, and perhaps, carry out immune endotyping of patients before prescribing appropriate drugs. This review summarizes the immunology of asthma, the cytokines or receptors currently targeted, the possible mechanisms of sub-optimal responses, and the importance of determining the immune make-up of individual patients prior to prescribing mAb therapy, in the age of precision medicine for asthma.

Anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis

BACKGROUND

Cystic fibrosis is an autosomal recessive multisystem disorder with an approximate prevalence of 1 in 3500 live births. Allergic bronchopulmonary aspergillosis is a lung disease caused by aspergillus-induced hypersensitivity with a prevalence of 2% to 15% in people with cystic fibrosis. The mainstay of treatment includes corticosteroids and itraconazole. The treatment with corticosteroids for prolonged periods of time, or repeatedly for exacerbations of allergic bronchopulmonary aspergillosis, may lead to many adverse effects. The monoclonal anti-IgE antibody, omalizumab, has improved asthma control in severely allergic asthmatics. The drug is given as a subcutaneous injection every two to four weeks. Since allergic bronchopulmonary aspergillosis is also a condition resulting from hypersensitivity to specific allergens, as in asthma, it may be a candidate for therapy using anti-IgE antibodies. Therefore, anti-IgE therapy, using agents like omalizumab, may be a potential therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis. This is an updated version of the review.

OBJECTIVES

To evaluate the efficacy and adverse effects of anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. Last search: 09 September 2021. We searched two ongoing trial registries (Clinicaltrials.gov and the WHO trials platform). Date of latest search: 16 August 2021.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing anti-IgE therapy to placebo or other therapies for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias in the included study. They planned to perform data analysis using Review Manager.

MAIN RESULTS

Only one study enrolling 14 participants was eligible for inclusion in the review. The double-blind study compared a daily dose of 600 mg omalizumab or placebo along with twice daily itraconazole and oral corticosteroids, with a maximum daily dose of 400 mg. Treatment lasted six months but the study was terminated prematurely and complete data were not available. We contacted the study investigator and were told that the study was terminated due to the inability to recruit participants into the study despite all reasonable attempts. One or more serious side effects were encountered in six out of nine (66.67%) and one out of five (20%) participants in omalizumab group and placebo group respectively.

AUTHORS' CONCLUSIONS

There is lack of evidence for the efficacy and safety of anti-IgE (omalizumab) therapy in people with cystic fibrosis and allergic bronchopulmonary aspergillosis. There is a need for large prospective randomized controlled studies of anti-IgE therapy in people with cystic fibrosis and allergic bronchopulmonary aspergillosis with both clinical and laboratory outcome measures such as steroid requirement, allergic bronchopulmonary aspergillosis exacerbations and lung function.

Evolution of our view on the IgE molecule role in bronchial asthma and the clinical effect of its modulation by omalizumab: Where do we stand today?

Bronchial asthma is a heterogeneous disease whose definition and treatment are based on evidence of variable airway obstruction and airway inflammation. Despite the enormous increase in the amount of information on the pathogenesis of this disease, diagnosis is still an unresolved problem, as we still lack sensitive and specific biomarkers. On the other hand, at the turn of the 20th and 21st century, there was a rapid development of therapeutic modalities based on the principle of biological therapy. The first authorized drug matching these characteristics was omalizumab – a monoclonal antibody directed against immunoglobulin E (IgE). It has been used for the treatment of severe forms of bronchial asthma for more than 15 years, which is a sufficient time to acquire ways of its effective use and to assess whether the treatment with omalizumab has met our expectations. However, we continue to discover new and surprising facts about the effects of omalizumab treatment which leads to widening of therapeutic indications. In this work, a basic overview of the very complex role of the IgE molecule in the organism (with a special emphasis on allergic asthma) is discussed, and the most important practical and clinical consequences resulting from its modulation by targeted therapy with omalizumab are summarized.

Past, present, and future of anti-IgE biologics

About 20 years after the identification of immunoglobulin E (IgE) and its key role in allergic hypersensitivity reactions against normally harmless substances, scientists have started inventing strategies to block its pathophysiological activity in 1986. The initial concept of specific IgE targeting through the use of anti-IgE antibodies has gained a lot of momentum and within a few years independent research groups have reported successful generation of first murine monoclonal anti-IgE antibodies. Subsequent generation of optimized chimeric and humanized versions of these antibodies has paved the way for the development of therapeutic anti-IgE biologicals as we know them today. With omalizumab, there is currently still only one therapeutic anti-IgE antibody approved for the treatment of allergic conditions. Since its application is limited to the treatment of moderate-to-severe persistent asthma and chronic spontaneous urticaria, major efforts have been undertaken to develop alternative anti-IgE biologicals that could potentially be used in a broader spectrum of allergic diseases. Several new drug candidates have been generated and are currently assessed in pre-clinical studies or clinical trials. In this review, we highlight the molecular properties of past and present anti-IgE biologicals and suggest concepts that might improve treatment efficacy of future drug candidates.

Targeted biologic therapy for asthma

BACKGROUND

Asthma is a common and potentially serious condition affecting 300 million people worldwide. For many years, we have relied on a one-size-fits-all approach to its management, using corticosteroids and bronchodilators for all symptomatic patients. However, with more recent advances, it has become clear that asthma is a heterogeneous condition with multiple different underlying pathways. Understanding the different subtypes will be a key to giving us the ability to intervene in a targeted way to personalize care for patients with asthma.

SOURCES OF DATA

Key published literature, guidelines and trials from clinicaltrials.gov.

AREAS OF AGREEMENT

The most widely studied of these subtypes is T2 high eosinophilic asthma, for which there are an increasing number of biologic therapies available. T2 high asthma is associated with the cytokines interleukin (IL)-4, IL-5 and IL-13, for each of which biologics have been developed.

AREAS OF CONTROVERSY

It is currently unclear which of the available biologics provides superior efficacy. It is also unclear how to select which biologic for which patient.

GROWING POINTS

Head-to-head trials of the available T2 biologics will be important to determine superiority, and a suggested order for trialling biologics. Going further than this, we would like to see further analyses of available biologics to allow us to predict responders from non-responders in advance of administering therapy.

AREAS TIMELY FOR DEVELOPING RESEARCH

Non-eosinophilic T2 low asthma is an area that is under-researched and for which there are few treatments available. It is likely that there are different subtypes in this category of asthma and unravelling what these are will be crucial to developing effective treatments.

Generation of IgE-specific cytotoxic T lymphocytes as a novel immunotherapeutic approach for the treatment of allergic asthma

INTRODUCTION

Overproduction of immunoglobulin E (IgE) by a subset of B cells plays a key role in the pathogenesis of allergic asthma. Anti-IgE monoclonal antibodies have been successfully used to treat the disease, but long-term application is required.

METHODS

For this study, cytotoxic T lymphocytes (CTLs) against IgE-producing B cells were generated ex vivo by stimulating naive CD8 T cells with IgE-derived peptides presented by Drosophila-derived artificial antigen-presenting cells. Based on the treatment of allergic asthma in mice, the inhibitive effect of this CTL on IgE responses and airway inflammation was determined with the enzyme-linked immunosorbent assay and histochemical method.

RESULTS

The IgE-specific CTLs effectively lysed target cells in vitro, while the adoptively transferred CTLs specifically inhibited IgE responses and airway inflammation in an asthmatic mouse model. The effect of IgE-specific CTLs is MHC (major histocompatibility complex) Class I-restricted and requires the expression of perforin.

CONCLUSION

IgE-specific CTLs generated ex vivo may provide a novel treatment for allergic asthma and lead to a new therapy for other immunological disorders.

Omalizumab for atopic dermatitis: evidence for and against its use

INTRODUCTION

Omalizumab, has been used for almost two decades, mainly in allergic asthma and chronic spontaneous urticaria for which it is highly beneficial. Smaller studies have evaluated the effects of omalizumab in atopic dermatitis (AD). Current treatments options, such as cyclosporine and azathioprine have limited effect on AD and numerous side effects. The recently introduced biologic dupilumab (anti-IL4) shows promising results, however with conjunctivitis as a prevalent side effect. We evaluate the current evidence for the use of omalizumab in AD.

EVIDENCE ACQUISITION

Systematic literature searches were performed in PubMed, Web of Science, Embase and Clinicaltrials.gov to identify any study (case reports, case series, and controlled trials) evaluating the effect of treatment with omalizumab in AD.

EVIDENCE SYNTHESIS

Thirty-four studies (12 single case studies, 15 case series, 5 prospective studies and 2 small pilot randomized placebo-controlled trials [RCTs]), including a total of 214 patients with median of 3, ranging from 1-35 patients were identified. A total of 169 patients (79.0%) experienced a beneficial effect from treatment, ranging from little to complete response, whereas 45 patients (21.0%) reported no or negative effect from omalizumab treatment.

CONCLUSIONS

Omalizumab is a safe and well-tolerated treatment with some clinical benefit in AD patients. However, the lack of larger RCTs and possible publication bias limit the recommendation of omalizumab for use in clinical practice for AD. Newer and more effective treatments exist and should be prioritized.

Anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis

BACKGROUND

Cystic fibrosis is an autosomal recessive multisystem disorder with an approximate prevalence of 1 in 3500 live births. Allergic bronchopulmonary aspergillosis is a lung disease caused by aspergillus-induced hypersensitivity with a prevalence of 2% to 15% in people with cystic fibrosis. The mainstay of treatment includes corticosteroids and itraconazole. The treatment with corticosteroids for prolonged periods of time, or repeatedly for exacerbations of allergic bronchopulmonary aspergillosis, may lead to many adverse effects. The monoclonal anti-IgE antibody, omalizumab, has improved asthma control in severely allergic asthmatics. The drug is given as a subcutaneous injection every two to four weeks. Since allergic bronchopulmonary aspergillosis is also a condition resulting from hypersensitivity to specific allergens, as in asthma, it may be a candidate for therapy using anti-IgE antibodies. Therefore, anti-IgE therapy, using agents like omalizumab, may be a potential therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis. This is an updated version of the review.

OBJECTIVES

To evaluate the efficacy and adverse effects of anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. Last search: 29 September 2017.We searched two ongoing trial registries (Clinicaltrials.gov and the WHO trials platform). Date of latest search: 24 January 2018.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing anti-IgE therapy to placebo or other therapies for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias in the included study. They planned to perform data analysis using Review Manager.

MAIN RESULTS

Only one study enrolling 14 participants was eligible for inclusion in the review. The double-blind study compared a daily dose of 600 mg omalizumab or placebo along with twice daily itraconazole and oral corticosteroids, with a maximum daily dose of 400 mg. Treatment lasted six months but the study was terminated prematurely and complete data were not available. We contacted the study investigator and were told that the study was terminated due to the inability to recruit participants into the study despite all reasonable attempts. One or more serious side effects were encountered in six out of nine (66.67%) and one out of five (20%) participants in omalizumab group and placebo group respectively.

AUTHORS' CONCLUSIONS

There is lack of evidence for the efficacy and safety of anti-IgE (omalizumab) therapy in people with cystic fibrosis and allergic bronchopulmonary aspergillosis. There is a need for large prospective randomized controlled studies of anti-IgE therapy in people with cystic fibrosis and allergic bronchopulmonary aspergillosis with both clinical and laboratory outcome measures such as steroid requirement, allergic bronchopulmonary aspergillosis exacerbations and lung function.

The clinical response to omalizumab in chronic spontaneous urticaria patients is linked to and predicted by IgE levels and their change

BACKGROUND

Omalizumab is an effective and well-tolerated treatment for chronic spontaneous urticaria (CSU). Markers and predictors of response are largely unknown, but needed to optimize omalizumab treatment. Omalizumab targets IgE, and IgE levels may be linked to the effects of treatment. We evaluated whether response rates to treatment with omalizumab in patients with CSU are linked to their baseline IgE levels, their IgE levels after omalizumab treatment, and the ratio of on treatment IgE and baseline IgE levels.

METHODS

Chronic spontaneous urticaria (CSU) patients (n = 113) were treated with omalizumab 300 mg/4 weeks for 12 weeks, when their treatment responses, that is, no, partial, or complete response, were assessed by use of the urticaria activity score, physician and patient visual analog scale, and treatment effectiveness score. Total IgE levels were measured before treatment (bIgE) with omalizumab and 4 weeks thereafter (w4IgE).

RESULTS

Nonresponders to omalizumab had significantly lower bIgE levels (17.9, 17.0-55.0 IU/mL) than partial responders (82.0, 46.2-126.5 IU/mL, P = .008) and complete responders (73.7, 19.45-153.8 IU/mL, P = .032). Nonresponders also had lower w4IgE levels and lower ratios of w4IgE/bIgE levels than partial and complete responders (P < .001). Nonresponse to omalizumab was best predicted by patients' w4IgE/bIgE ratios, significantly better than by bIgE levels (P = .016).

CONCLUSIONS

In CSU, total IgE levels and their change predict the response to treatment with omalizumab. The assessment of pre- and post-treatment IgE levels and their ratio may help to improve the management of CSU in patients who require omalizumab treatment.

Half-life of IgE in serum and skin: Consequences for anti-IgE therapy in patients with allergic disease

We present results from clinical studies on plasma infusion done in the late 1970s in patients with hypogammaglobulinemia in which we documented the short half-life of both total and allergen-specific IgE in serum. The development of specific allergic sensitization in the skin of those patients followed by the gradual decrease in sensitization over 50 days was also documented. The data are included here along with a discussion of the existing literature about the half-life of IgE in both the circulation and skin. This rostrum reinterprets the earlier clinical studies in light of new insights and mechanisms that could explain the rapid removal of IgE from the circulation. These mechanisms have clinical implications that relate to the increasing use of anti-IgE mAbs for the treatment of allergic disease.

From IgE to Omalizumab

IgE is the least abundant Ig isotype, yet it plays a critical role in allergic reactions and host protection from helminth infection. Although IgE was discovered 50 years ago, the ultimate evidence for its role in human allergic diseases was obtained by the efficacy of anti-IgE therapy in many clinical trials on asthma and other allergic diseases. Beginning from the discovery of IgE 50 y ago, followed by studies of IgE receptors and activation mechanisms, this review provides a historic perspective of allergy research that has led to the development of anti-IgE therapy and other strategies targeting IgE and its receptors. Current IgE studies toward future precision medicine are also reviewed.

Use of biologics to treat acute exacerbations and manage disease in asthma, COPD and IPF

A common feature of chronic respiratory disease is the progressive decline in lung function. The decline can be indolent, or it can be accelerated by acute exacerbations, whereby the patient experiences a pronounced worsening of disease symptoms. Moreover, acute exacerbations may also be a marker of insufficient disease management. The underlying cause of an acute exacerbation can be due to insults such as pathogens or environmental pollutants, or the cause can be unknown. For each acute exacerbation, the patient may require medical intervention such as rescue medication, or in more severe cases, hospitalization and ventilation and have an increased risk of death. Biologics, such as monoclonal antibodies, are being developed for chronic respiratory diseases including asthma, COPD and IPF. This therapeutic approach is particularly well suited for chronic use based on the route and frequency of delivery and importantly, the potential for disease modification. In recent clinical trials, the frequency of acute exacerbation has often been included as an endpoint, to help determine whether the investigational agent is impacting disease. Therefore the significance of acute exacerbations in driving disease, and their potential as a marker of disease activity and progression, has recently received much attention. There is also now a need to standardize the definition of an acute exacerbation in specific disease settings, particularly as this endpoint is increasingly used in clinical trials to also assess therapeutic efficacy. Moreover, specifically targeting exacerbations may offer a new therapeutic approach for several chronic respiratory diseases.

PK/PD analysis of a novel pH-dependent antigen-binding antibody using a dynamic antibody-antigen binding model

Previously, we have reported novel engineered antibody with pH-dependent antigen-binding (recycling antibody), and with both pH-dependent antigen-binding and increased FcRn-binding at neutral pH (sweeping antibody). The purpose of this study is to perform PK/PD predictions to better understand the potential applications of the antibodies as therapeutics. To demonstrate the applicability of recycling and sweeping antibodies over conventional antibodies, PK/PD analyses were performed. PK/PD parameters for antibody and antigen dynamics were estimated from the results of a pharmacokinetic study in human FcRn transgenic mice. A simulation study was performed using the estimated PK/PD parameters with various target antigen profiles. In comparison to conventional antibody, recycling antibody enhanced antibody-antigen complex clearance by 3 folds, while sweeping antibody accelerated antigen clearance by 10 folds in a pharmacokinetic study. Simulation results showed that recycling and sweeping antibodies can improve dosage frequency and reduce the required dose for target antigens with various clearances, plasma concentrations or binding kinetics. Moreover, importance of the association rate constant to enhance the beneficial effect of antibodies was shown. These results support the conclusion that recycling and sweeping antibodies can be applied to various target antigens with different profiles, and expand the number of antigens that antibodies can target.

Anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis

BACKGROUND

Cystic fibrosis is an autosomal recessive multisystem disorder with an approximate prevalence of 1 in 3500 live births. Allergic bronchopulmonary aspergillosis is a lung disease caused by aspergillus-induced hypersensitivity with a prevalence of 2% to 15% in people with cystic fibrosis. The mainstay of treatment includes corticosteroids and itraconazole. The treatment with corticosteroids for prolonged periods of time, or repeatedly for exacerbations of allergic bronchopulmonary aspergillosis, may lead to many adverse effects. The monoclonal anti-IgE antibody, omalizumab, has improved asthma control in severely allergic asthmatics. The drug is given as a subcutaneous injection every two to four weeks. Since allergic bronchopulmonary aspergillosis is also a condition resulting from hypersensitivity to specific allergens, as in asthma, it may be a candidate for therapy using anti-IgE antibodies. Therefore, anti-IgE therapy, using agents like omalizumab, may be a potential therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis. This is an updated version of the review.

OBJECTIVES

To evaluate the efficacy and adverse effects of anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. Last search: 27 July 2015.We searched the ongoing trial registry clinicaltrials.gov for any ongoing trials. Latest search for clinicaltrials.gov: 23 October 2015.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing anti-IgE therapy to placebo or other therapies for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias in the included study. They planned to perform data analysis using Review Manager.

MAIN RESULTS

Only one study enrolling 14 participants was eligible for inclusion in the review. The double-blind study compared a daily dose of 600 mg omalizumab or placebo along with twice daily itraconazole and oral corticosteroids, with a maximum daily dose of 400 mg. Treatment lasted six months but the study was terminated prematurely and complete data were not available. We contacted the study investigator and were told that the study was terminated due to the inability to recruit participants into the study despite all reasonable attempts. One or more serious side effects were encountered in six out of nine (66.67%) and one out of five (20%) participants in omalizumab group and placebo group respectively.

AUTHORS' CONCLUSIONS

There is lack of evidence for the efficacy and safety of anti-IgE (omalizumab) therapy in people with cystic fibrosis and allergic bronchopulmonary aspergillosis. There is a need for large prospective randomized controlled studies of anti-IgE therapy in people with cystic fibrosis and allergic bronchopulmonary aspergillosis with both clinical and laboratory outcome measures such as steroid requirement, allergic bronchopulmonary aspergillosis exacerbations and lung function.

The discovery and development of omalizumab for the treatment of asthma

INTRODUCTION

The evolution in immunological methods used to assess human allergic diseases has led to the identification of immunoglobulin E (IgE) as a diagnostic biomarker and a potential therapeutic target. Innovative technologies in molecular biology and immunogenetics contributed to the development of a selective blocking agent, disclosing new therapeutic perspectives in the treatment of allergic asthma. Omalizumab is the most advanced humanized anti-IgE monoclonal antibody that specifically binds serum-free IgE. Omalizumab also interrupts the allergic cascade by preventing binding of IgE with FcεRI receptors on mast cells, basophils, antigen-presenting cells and other inflammatory cells.

AREAS COVERED

This review discusses the discovery strategy and preclinical development of omalizumab. Furthermore, it also provides a clinical overview of the key trials leading to its launch and a detailed analysis of safety and post-marketing data.

EXPERT OPINION

The clinical efficacy of omalizumab in allergic asthma has been well documented in clinical trials, involving adults, adolescents and children with moderate-to-severe and severe allergic asthma. To date, omalizumab has also been approved in chronic idiopathic urticaria for patients 12 years and older who remain symptomatic despite high dosages of H1 antihistamines. Omalizumab has also been investigated in many other different patient populations beyond allergic asthma and may yet have an application to other indications. While omalizumab is the only mAb available for treating allergic asthma, the authors anticipate that new mAbs will emerge in the future that overcome omalizumab's current limitations.

Developing therapies for peanut allergy

Peanut allergy is an IgE-mediated, persisting immune disorder that is of major concern worldwide. Currently, no routine immunotherapy is available to treat this often severe and sometimes fatal food allergy. Traditional subcutaneous allergen immunotherapy with crude peanut extracts has proven not feasible due to the high risk of severe systemic side effects. The allergen-specific approaches under preclinical and clinical investigation comprise subcutaneous, oral, sublingual and epicutaneous immunotherapy with whole-peanut extracts as well as applications of hypoallergenic peanut allergens or T cell epitope peptides. Allergen-nonspecific approaches include monoclonal anti-IgE antibodies, TCM herbal formulations and Toll-like receptor 9-based immunotherapy. The potential of genetically engineered plants with reduced allergen levels is being explored as well as the beneficial influence of lactic acid bacteria and soybean isoflavones on peanut allergen-induced symptoms. Although the underlying mechanisms still need to be elucidated, several of these strategies hold great promise. It can be estimated that individual strategies or a combination thereof will result in a successful immunotherapy regime for peanut-allergic individuals within the next decade.

New strategies with anti-IgE in allergic diseases

IgE has long been known as a therapeutic target for allergic disease, but the difficulty has been in selecting agents that don't trigger cross linkage of IgE when bound to its high affinity receptor (FceR1) on mast cells and basophils. By "designing" a monoclonal antibody (mAb) which targets that part of IgE that binds to that binds to the a-chain of FceR1, the allergic cascade can be effectively interrupted and diseases such as asthma greatly improved, providing a substantial part of their phenotype engages IgE. Clinical trials and real life studies confirm this. Beyond asthma, a whole range of other diseases dependent upon IgE initiation and triggering are being identified. These diseases are now being explored as being amenable to anti-IgE therapy some of which are comorbidities of asthma and others not. The advent of an even more potent anti-IgE mAb - QGE031 - is creating further opportunities for anti-IgE therapy to improve the lives of so many people with IgE-related diseases.

What Taiwan contributes to the world of allergy and clinical immunology?

In commemorate the 9th Asia Pacific Congress of Allergy, Asthma, and Clinical Immunology (APCAACI) in Taipei, Taiwan in November this year, some of the seminar works and contributions by the researchers from Taiwan to the advance in the field of allergy and clinical immunology, such as DNA vaccine, traditional Chinese medicine, anti-IgE antibody, and personalized medicine for severe drug allergic reaction, are summarized in this special review.

Anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis

BACKGROUND

Cystic fibrosis is an autosomal recessive multisystem disorder with an approximate prevalence of 1 in 3500 live births. Allergic bronchopulmonary aspergillosis is a lung disease caused by aspergillus-induced hypersensitivity with a prevalence of 2% to 15% in people with cystic fibrosis. The mainstay of treatment includes corticosteroids and itraconazole. The treatment with corticosteroids for prolonged periods of time, or repeatedly for exacerbations of allergic bronchopulmonary aspergillosis, may lead to many adverse effects. The monoclonal anti-IgE antibody, omalizumab, has improved asthma control in severely allergic asthmatics. The drug is given as a subcutaneous injection every two to four weeks. Since allergic bronchopulmonary aspergillosis is also a condition resulting from hypersensitivity to specific allergens, as in asthma, it may be a candidate for therapy using anti-IgE antibodies. Therefore, anti-IgE therapy, using agents like omalizumab, may be a potential therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

OBJECTIVES

To evaluate the efficacy and adverse effects of anti-IgE therapy for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. Last search: 21 January 2013.We searched the ongoing trial registry clinicaltrials.gov for any ongoing trials. Latest search for clinicaltrials.gov: 22 February 2013.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing anti-IgE therapy to placebo or other therapies for allergic bronchopulmonary aspergillosis in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias in the included study. They planned to perform data analysis using Review Manager 5.1.

MAIN RESULTS

Only one trial enrolling 14 patients was eligible for inclusion in the review. The study was terminated prematurely and complete data were not available. We contacted the study investigator and were told that the study was terminated due to the inability to recruit patients into the study despite all reasonable attempts. One or more serious side effects were encountered in six out of nine (66.67%) and one out of five (20%) patients in omalizumab group and placebo group respectively.

AUTHORS' CONCLUSIONS

There is lack of evidence for the efficacy and safety of anti-IgE (omalizumab) therapy in patients with cystic fibrosis and allergic bronchopulmonary aspergillosis. There is a need for large prospective randomized controlled trials of anti-IgE therapy in people with cystic fibrosis and allergic bronchopulmonary aspergillosis with both clinical and laboratory outcome measures such as steroid requirement, allergic bronchopulmonary aspergillosis exacerbations and lung function.

Mechanisms of asthma and implications for its prevention and treatment: a personal journey

My research career has focused on the causes of asthma and its treatment. After establishing the key role that mast cells play in the inflammatory response in asthma, attention was turned towards understanding disease chronicity and variability across the lifecourse. Through a combination of studies on airway biopsies and primary cell cultures we have established that asthma is primarily an epithelial disease driven by increased environmental susceptibility to injury and an altered repair response as depicted by sustained activation of the epithelial mesenchymal trophic unit (EMTU) that is invoked in foetal branching morphogenesis. Varied activation of the EMTU connects the origins of asthma to its progression over time with involvement of epithelial susceptibility through impaired barrier and innate immune functions and altered mesenchymal susceptibility as exemplified by polymorphisms of the metalloprotease gene, ADAM33. Taken together these observations have led to a fundamental re-evaluation of asthma pathogenesis. Rather than placing allergic inflammation as the prime abnormality, it is proposed that the airway epithelium lies at the center of asthma pathogenesis, and that in conjunction with the underlying mesenchyme, it is the principle orchestrator of both the induction of asthma and its evolution over the lifecourse. This concept has provided 'the basis for a new preventative and therapeutic approach focused more on increasing the airways resistance to environmental insults rather than suppressing downstream inflammation once it is established.

Asthma: beyond corticosteroid treatment

Asthma is one of the most common chronic diseases in the world, affecting over 300 million people. It is an inflammatory disorder characterized by bronchoconstriction and airway hyperresponsiveness, followed by inflammatory manifestations in the respiratory system. The prevalence of asthma is rising and there is a clinical need to develop more effective treatments. While corticosteroids (glucocorticosteroids) remain the mainstay of asthma therapy, they have limitations because of their potentially severe side-effects and the presence of corticosteroid resistance in some patients. This review discusses current strategies in the treatment of asthma and considers new therapeutic regimens of asthma in the drug development pipeline.

Prospects for a vaccine in allergic diseases and asthma

Allergen-specific immunotherapy is widely used to treat allergic diseases, and current research is now focusing on the development of therapeutic vaccines acting on the IgE immune response following allergen challenge. The IgE immune response is dependent on genetic and environmental factors; production of IgE results from complex interactions among B cells, T cells, mast cells, basophils,surface and adhesion molecules and various cytokines. New vaccination methods under investigation involve allergen-specific or nonspecific methodology. Allergen-specific methods currently being developed include allergoids, passive saturation of effector cells, plasmid DNA immunisation and antigen-antibody complexes. The mechanisms of immunotherapy using allergen-specific methods differ with the allergens and the route of immunisation used (parenteral, intranasal, sublingual, oral or bronchial). Many vaccines being developed at present comprise synthetic, recombinant or highly purified subunit antigens, which although they have increased safety may also be less immunogenic.It is hoped that the addition of adjuvants will overcome this drawback. Methods of increasing the dose of allergen while reducing the possibility of an anaphylactic reaction include the use of non-anaphylactic isoforms of the allergens, alteration of the tertiary structure of the allergens and construction of minimal allergen-derived T cell peptides. Nonspecific approaches include humanised anti-IgE antibodies,moderation of the T(H)2 cytokine network and antisense oligodeoxynucleotide therapy.

Helminth therapy (worms) for allergic rhinitis

BACKGROUND

Allergic rhinitis is a disorder of the nasal membranes and surrounding tissues, and a worldwide cause of illness and disability. Helminths are complex tissue-dwelling or lumen-dwelling organisms that inhabit larger organisms and are frequently asymptomatic. Helminths modulate the natural immune responses of their human hosts, and may prevent or cure immune-mediated or allergic diseases (e.g. allergic rhinitis) in the host. Non-randomised studies support this hypothesis.

OBJECTIVES

To assess the safety and effectiveness of helminth therapy in people with allergic rhinitis.

SEARCH METHODS

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the search was 24 June 2011.

SELECTION CRITERIA

All randomised controlled trials where the intervention was any helminth species or combination of helminth species, administered to people with allergic rhinitis in any dose, by any route and for any duration of exposure. We accepted both intermittent and persistent allergic rhinitis patients.

DATA COLLECTION AND ANALYSIS

We independently extracted data and assessed eligibility and risk of bias using a standardised data collection form. We resolved any disagreement through discussion. We combined dichotomous data using risk ratio (RR) and continuous data using mean difference (MD), presenting both with 95% confidence intervals (CI).

MAIN RESULTS

We found five reports of two single-centre, placebo-controlled, double-blinded studies (130 participants). Participants in both studies were a mix of adults with either intermittent or persistent allergic rhinitis. Both studies had a low risk of bias. One study, with 12 weeks' follow-up, used a single percutaneous application of 10 Necator americanus (i.e. human hookworm) larvae. The other study, with 24 weeks' follow-up, used three-weekly oral dosing with 2500 Trichuris suis (i.e. pig whipworm) eggs in aqueous suspension. Of 17 outcomes evaluated in this review, eight were positive (i.e. favoured helminths). Participants taking helminths had no reduction in allergic rhinitis symptoms, percentage of well days (i.e. days with minimal symptoms and no use of medication for allergic rhinitis), lung function measures and quality of life scores. Total use of medication for allergic rhinitis (eye drops, nasal sprays, tablets) did not change; however, in the helminth group there was a statistically significant reduction in the percentage of days during the grass pollen season when participants needed to take tablets as rescue medication for their allergic rhinitis symptoms (MD -14.0%, 95% CI -26.6 to -1.40); in a typical 60-day pollen season this 14% reduction translates into 19 days when tablets would be needed in the helminth group versus 27 days when tablets would be needed in the placebo group. Participants taking helminths percutaneously (i.e. as hookworm larvae) had local skin itching and redness in the first few days after administration. Participants taking helminths were more likely to report any gastrointestinal adverse event (RR 1.79, 95% CI 1.31 to 2.45), moderate or severe abdominal pain (RR 7.67, 95% CI 1.87 to 31.57), moderate or severe flatulence (RR 2.01, 95% CI 1.06 to 3.81) and moderate or severe diarrhoea (RR 1.99, 95% CI 1.18 to 3.37). There was no difference between the helminth and placebo groups in the incidence of serious adverse events, and in study withdrawals.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence on the efficacy, tolerability and likely costs of helminth therapy to support its use in the routine management of allergic rhinitis. Administered to humans in carefully measured doses, helminths appear to be safe. More preclinical studies should be performed, before larger and extended duration trials of helminths for allergic rhinitis are carried out. Future studies should collect and report comparative data on the costs of helminth therapy versus conventional pharmacotherapy.

Monoclonal antibodies for chronic refractory asthma and pipeline developments

Patients with severe asthma suffer persistent symptoms and/or frequent exacerbations despite high-intensity treatment. Their severe unrelenting symptoms have a huge impact on healthcare resources owing to frequent hospital admissions and requirement for intensive treatments. Consequently, there is an undeniable need for more-effective and safer medications. Expanding knowledge of innate and adaptive immune responses is leading to the development of novel therapies for severe asthma. Herein, we review efficacy and safety data from human clinical trials of monoclonal antibodies that are approved or under investigation for use in asthma. Future drug candidates directed at key targets and the specific role of monoclonal antibodies in distinctively targeted sub-populations of severe asthmatics will be also discussed.

Monoclonal antibodies for the treatment of asthma

Asthma is a chronic inflammatory disease of the airways which can have a detrimental effect on quality of life and in extreme cases cause death. Although the majority of patients can control their asthma symptoms with a combination of steroids and beta agonists there is still a group of patients whose asthma remains symptomatic despite the best available treatment. These severe asthmatic patients represent the unmet medical need in asthma and are the focus of those developing novel monoclonal antibody based drugs. The complex networks of cytokines and cells involved in the pathology of asthma provide plenty of scope for intervention with monoclonal antibody based drugs which are able to block cytokine or chemokine receptor interactions, deplete cells expressing a specific receptor or block cell/cell interactions. At present anti-IgE (Xolair©) is the only monoclonal antibody based drug approved for the treatment of asthma. However, a number of other antibody based drugs have been clinically tested in asthma including anti-IL-5, anti-IL-4, anti-IL-13, anti-TNFα, anti-CCR3, anti-CCR4 and anti-OX40L. This review will examine the development of these monoclonal antibody based therapies. Since many of these therapies have targeted key pathways in asthma pathology these studies provide information on patient stratification and asthma pathology.

Monoclonal antibodies for the treatment of severe asthma

Patients with severe asthma have a significant unmet need with persistent symptoms and/or frequent exacerbations despite treatment with high-dose steroid and other currently available therapies. These patients are also at risk of developing steroid-related side effects, and their severe, unrelenting symptoms have a huge impact on health care resources due to frequent hospital admissions and requirement for intensive medication use. Consequently, a compelling need exists for more effective and safer pharmacotherapies to help them achieve adequate disease control. Recent novel therapies for severe asthma are now emerging, some of the most promising of which are monoclonal antibodies. Monoclonal antibodies represent a form of immunotherapy used in a wide variety of therapeutic roles. The spectrum of disease states in which monoclonal antibodies have been approved for therapeutic use now includes respiratory and allergic diseases. At present, only one drug is licensed for allergic asthmatics with severe disease, omalizumab. We review some of the currently available biologics that are approved or under investigation for use in severe asthma. Some have shown to be useful in specifically targeted subpopulations of patients with severe asthma, whereas other have proven to be unsafe and/or unsuccessful. Despite these developments, more effort should be devoted to identifying new molecular targets, testing innovative approaches, and establishing the best use of what is available. Regarding this latter point, identifying individual characteristics that predict successful responses to these treatments is highly desirable.

A peptide binding to dimerized translationally controlled tumor protein modulates allergic reactions

Translationally controlled tumor protein (TCTP) is believed to be involved in a variety of inflammatory processes: secretion of histamine and cytokines such as IL-4, IL-8, IL-13, and granulocyte/macrophage colony-stimulating factor; chemoattraction for eosinophils; augmentation of B cell proliferation; and immunoglobulin production, thereby potentially regulating allergic phenomena. In a previous study, we showed that the cytokine-releasing activity of extracellular TCTP is generated only when TCTP dimerizes via the intermolecular disulfide bond of NH(2)-terminal truncated TCTP implying that the dimerized TCTP (dTCTP) promotes the inflammatory phenomena. Modulation of dTCTP, thus, may offer a strategy for the treatment of chronic allergic diseases. In this study, we searched for dTCTP-binding peptides (dTBPs) by screening a phage-displayed 7-mer peptide library. We identified one peptide in the library, designated as dTBP2, which showed higher affinity to dTCTP than to full-length, monomeric TCTP. dTBP2 inhibited the induction of IL-8 by dTCTP from BEAS-2B cells. dTBP2 also reduced symptom score and eosinophil infiltration in a mouse rhinitis model. This study suggests that the dTBP2 binding to dTCTP modulates the release of inflammatory mediators of dTCTP. This result may provide a rational strategy for the treatment of allergic diseases.

Airway remodeling in asthma: new mechanisms and potential for pharmacological intervention

The chronic inflammatory response within the airways of asthmatics is associated with structural changes termed airway remodeling. This remodeling process is a key feature of severe asthma. The 5-10% of patients with a severe form of the disease account for the higher morbidity and health costs related to asthma. Among the histopathological characteristics of airway remodeling, recent reports indicate that the increased mass of airway smooth muscle (ASM) plays a critical role. ASM cell proliferation in severe asthma implicates a gallopamil-sensitive calcium influx and the activation of calcium-calmodulin kinase IV leading to enhanced mitochondrial biogenesis through the activation of various transcription factors (PGC-1α, NRF-1 and mt-TFA). The altered expression and function of sarco/endoplasmic reticulum Ca(2+) pump could play a role in ASM remodeling in moderate to severe asthma. Additionally, aberrant communication between an injured airway epithelium and ASM could also contribute to disease severity. Airway remodeling is insensitive to corticosteroids and anti-leukotrienes whereas the effect of monoclonal antibodies (the anti-IgE omalizumab, the anti-interleukin-5 mepolizumab or anti-tumor necrosis factor-alpha) remains to be investigated. This review focuses on potential new therapeutic strategies targeting ASM cells, especially Ca(2+) and mitochondria-dependent pathways.

Quantitation of serum IgE by using chimeras of human IgE receptor and avian immunoglobulin domains

Anti-IgE therapeutics represent an efficient approach in the management of IgE-mediated allergic asthma. However, monitoring the reduction of IgE levels into a therapeutically efficient range requires the determination of residual serum IgE. We established an analytical approach to distinguish free and anti-IgE complexed serum IgE based on soluble derivatives of the human high-affinity IgE receptor. Soluble receptor derivatives represent an ideal means to analyze receptor antagonism by any ligand or blocking antibody. Therefore, the FcεRI ectodomain was fused with avian IgY constant domains that circumvent susceptibility to interference phenomena and improve assay performance. After production in HEK293 cells, subsequent characterization by enzyme-linked immunosorbent assay and immunoblotting confirmed the suitability of avian IgY constant domains for immobilization and detection purposes. To provide further insights into the different IgE reactivities, free allergen-specific IgE was also determined. Monitoring of sera from omalizumab-treated patients during the course of therapy revealed the applicability for assessment of omalizumab-complexed versus noncomplexed serum IgE. These parameters may allow correlation to clinical responses during anti-IgE therapy with the perspective of biomonitoring.

DARPins against a functional IgE epitope

The monoclonal anti-IgE antibody omalizumab (Xolair is mostly used for the treatment of severe allergic asthma. However, the requirement of high doses and suboptimal cost-effectiveness limits the use of the treatment. Here we propose to use a new drug format based on non-immunoglobulin structures, potentially offering increased clinical efficacy while being more cost-effective. For this purpose, DARPins™ (designed ankyrin repeat proteins) against the constant heavy chain region of IgE have been isolated. DARPins were binding to IgE with high specificity and affinities in the low nanomolar range. Selected DARPins antagonized the interaction between IgE and its high-affinity receptor in inhibition assays. Furthermore, anti-IgE DARPins were shown to inhibit proinflammatory mediator release from rat basophilic leukemia cells expressing human high-affinity IgE receptors with higher efficacy than the monoclonal anti-IgE antibody omalizumab. DARPins may thus represent promising future drug candidates for the treatment of allergy.

Immunotherapy for allergies and asthma: present and future

Allergen immunotherapy (IT) is a proven approach for treating allergic rhinitis and allergic asthma that has been practiced since 1911 and has undergone significant development in the past two decades. As currently practiced, IT involves subcutaneous or sublingual administration of allergens, both methods of which have been extensively investigated. In addition to allergen IT, a number of additional nonspecific IT approaches are being used or are in phase II/phase III clinical trials, which may be available in clinics within the next one to three years. Such therapies include anti-IgE antibodies and the soluble IL-4 receptor. Other experimental IT approaches are at the preclinical research stage and may proceed to clinical trials and the clinic within the next five to ten years. This review discusses the pros and cons of recent developments in both currently practiced and experimental IT approaches.

Omalizumab for the treatment of severe allergic asthma

Omalizumab is the first of a new generation of targeted asthma therapies. This monoclonal antibody against IgE is now licensed for use in atopic asthma. The majority of asthmatics are well controlled with conventional therapies. However, there remains a cohort of patients with severe refractory asthma, despite currently available treatments ( approximately 5-10% of asthmatics), which account for approximately 50% of direct expenditure on asthma care. This article examines the evidence for both clinical and cost-effectiveness of omalizumab in patients with severe asthma and gives a 5-year view on the likely role of omalizumab in clinical practice.

Neutralization of IFNgamma defeats haemophagocytosis in LCMV-infected perforin- and Rab27a-deficient mice

Hereditary haemophagocytic lymphohistiocytosis (HLH) is a fatal inflammatory disease and treatments currently may lead to serious side effects. There is a pressing need for effective, less toxic treatments for this disease. Previous reports have suggested that interferon γ (IFNγ) has a role in the pathogenesis of HLH. Here, we report that blocking IFNγ had a therapeutic effect in two different murine models of human hereditary HLH (perforin-deficient and Rab27a-deficient mice, both infected with lymphocytic choriomeningitis virus). Therapeutic administration of an anti-IFNγ antibody induced recovery from haemophagocytosis in both genetic models, as evidenced by increased survival in perforin-deficient mice and correction of blood cytopenia, moderation of body temperature changes, decreased cytokinaemia, restoration of splenic architecture and reduced haemophagocytosis in the liver of both murine models. Involvement of the central nervous system in Rab27a-deficient mice was prevented by anti-IFNγ therapy. Hepatic T-cell infiltrates and virus persisted, with no detectable harm during the time course of these studies. These data strongly suggest that neutralization of IFNγ could be used in humans to safely alleviate the clinical manifestations of haemophagocytosis.

Antibodies specific for a segment of human membrane IgE deplete IgE-producing B cells in humanized mice

IgE-mediated hypersensitivity is central to the pathogenesis of asthma and other allergic diseases. Although neutralization of serum IgE with IgE-specific antibodies is in general an efficacious treatment for allergic asthma, one limitation of this approach is its lack of effect on IgE production. Here, we have developed a strategy to disrupt IgE production by generating monoclonal antibodies that target a segment of membrane IgE on human IgE-switched B cells that is not present in serum IgE. This segment is known as the M1' domain, and using genetically modified mice that contain the human M1' domain inserted into the mouse IgE locus, we demonstrated that M1'-specific antibodies reduced serum IgE and IgE-producing plasma cells in vivo, without affecting other immunoglobulin isotypes. M1'-specific antibodies were effective when delivered prophylactically and therapeutically in mouse models of immunization, allergic asthma, and Nippostrongylus brasiliensis infection, likely by inducing apoptosis of IgE-producing B cells. In addition, we generated a humanized M1'-specific antibody that was active on primary human cells in vivo, as determined by its reduction of serum IgE levels and IgE plasma cell numbers in a human PBMC-SCID mouse model. Thus, targeting of human IgE-producing B cells with apoptosis-inducing M1'-specific antibodies may be a novel treatment for asthma and allergy.

A brief history of asthma and its mechanisms to modern concepts of disease pathogenesis

The original concept of asthma being primarily a disease of airways smooth muscle drove the development of bronchodilator drugs. However when it was realised that airway inflammation underpinned the disordered airway function, this gave way to the development of controller therapies such as inhaled cromones and corticosteroids. More recently the discovery of complex interconnecting cytokine and chemokine networks has stimulated the development of biologics with varying success. With the recognition that airway wall "remodelling" is present early in asthma inception and is in part driven by aberrant epithelial-mesenchymal communication both genetic and environmental factors beyond allergen exposure such as virus infection and air pollution are being seen as being increasingly important not only in asthma exacerbations but in the origins of asthma and its evolution into different sub-phenotypes. This brings us round full circle to once again considering that the origins of asthma lie in defects in the formed elements of the airway; the epithelium, smooth muscle, and vasculature. Over the last 25 years Professor You Young Kim has engaged in the exciting discovery science of allergy and asthma and has made an enormous contribution in bringing Korea to the forefront of disease management and research, a position that both he and his colleagues can justly be proud of.

Critical comparison of MS and immunoassays for the bioanalysis of therapeutic antibodies

Therapeutic antibody assessment in biofluids requires fit-for-purpose bioanalytical methods. The reference is the immunoassay, the accuracy of which may be compromised by interference by endogenous components. Here, we report the inherent analytical problems posed by immunoassays and propose an alternative based on LC–MS that should be readily applicable to the analysis of therapeutic antibodies in biological fluids. We review problems linked to assay sensitivity, the choice of the assay format involving either immunodetection or MS, and strategies in the assessment of bound versus free forms.

Immunodrugs: therapeutic VLP-based vaccines for chronic diseases

Worldwide, the prevalence of noncommunicable chronic diseases is increasing. The use of vaccines to induce autoantibodies that neutralize disease-related proteins offers a means to effectively and affordably treat such diseases. Twenty vaccines designed to induce therapeutic autoantibodies were clinically tested in the past 12 years. Immunodrugs are therapeutic vaccines comprising virus-like particles (VLPs) covalently conjugated with self-antigens that induce neutralizing autoantibody responses. Four such VLP-based vaccines have been clinically tested and one has achieved proof of principle: a reduction of blood pressure in hypertensive patients. To facilitate preliminary clinical testing, novel nonclinical study programs have been developed. Safety study designs have considered the underlying B and T cell immunology and have examined potential toxicities of vaccine components and primary and secondary pharmacodynamic action of the vaccines.

A therapeutic antibody and its antigen form different complexes in serum than in phosphate-buffered saline: a study by analytical ultracentrifugation

During the development of protein therapeutics, characterization of the active pharmaceutical ingredient is performed extensively to ensure the stability, safety, and efficacy of the drug. Little is known, however, about the characteristics of protein drugs circulating in the blood. The recent availability of a fluorescence detection system (FDS) in analytical ultracentrifugation (AUC) instruments enables the characterization of fluorescently labeled proteins in biological fluids. AUC provides information about protein size, shape, self-association, and binding while avoiding many limitations associated with size exclusion chromatography. Furthermore, with the specificity and sensitivity of FDS, measurements can be performed at physiological concentrations directly in serum. In the current study, we used omalizumab, an anti-immunoglobulin E (IgE) monoclonal antibody, to demonstrate the potential of using AUC-FDS for the study of a monoclonal antibody and its complexes directly in human serum. Omalizumab properties were essentially unaltered after labeling with the fluorescent dye Alexa Fluor 488. In addition, omalizumab and IgE formed different complexes in serum than in phosphate-buffered saline in terms of both size and affinity.

Novel targets of therapy in asthma

PURPOSE OF REVIEW

The use of inhaled corticosteroids, short and long acting beta2-adrenoceptor agonists and inhibitors of leukotrienes provide most asthmatic patients with good disease control. However, none of these therapies are specifically directed to the underlying causal pathways of asthma. In this review the role of selective inhibitors of the inflammatory cascade are presented with a particular emphasis on biologics.

RECENT FINDINGS

Apart from antihuman immunoglobulin E, biologics have had little impact on this disease. However, with the definition of critical pathways in driving ongoing inflammation and airway remodelling, the situation is about to change with several exciting new approaches being on the horizon. Specific cytokines that are considered central to the Th2 inflammatory response as therapeutic targets are discussed along with some entirely new approaches such as restoration of mucosal innate immunity and epithelial barrier function and the application of radiofrequency ablation of airway smooth muscle or thermal bronchoplasty.

SUMMARY

What is becoming clear in filling the pipeline with new asthma therapies that treat the underlying disease causes is the need for closer working between clinical academics and industry to ensure that there is a rapid and sustained transfer of knowledge on novel targets through to their validation, proof of concept studies and clinical trials.

Omalizumab: the evidence for its place in the treatment of allergic asthma

INTRODUCTION

Asthma is a chronic inflammatory airways disease associated with reversible airflow obstruction and bronchial hyperresponsiveness. Asthma is prevalent worldwide and results in significant morbidity, mortality, and healthcare costs, the majority of which arise from those with severe disease. Omalizumab is a monoclonal antibody to immunoglobulin E (IgE) that has been developed for the treatment of severe persistent allergic (IgE mediated) asthma.

AIMS

The aim of this review is to evaluate the available clinical evidence on omalizumab to determine the role it has to play in the treatment of persistent allergic asthma.

EVIDENCE REVIEW

There is clear evidence to show that omalizumab is effective in reducing the rate of asthma exacerbations, inhaled corticosteroid dose, and the need for rescue medication in patients with allergic asthma. Clinical data indicate beneficial effects on patient-reported symptoms and perceived quality of life, as well as a reduction in unscheduled healthcare visits. There is little evidence to suggest omalizumab may enhance lung function or reduce the requirement for oral corticosteroids. Omalizumab has a favorable safety profile, although anaphylaxis has occurred. A study in children showed similar results to those achieved in adults and adolescents, with fewer asthma exacerbations and school days missed. Omalizumab may be cost effective in patients when used as add-on therapy to inhaled corticosteroids and long-acting beta(2) agonists (LABA).

PLACE IN THERAPY

Omalizumab is an effective add-on therapy to inhaled corticosteroids and LABAs in adults and adolescents with severe persistent allergic asthma. Currently there is insufficient evidence to support the use of omalizumab in children.