Management of asthma with anti-immunoglobulin E: a review of clinical trials of omalizumab

Immunoglobulin E (IgE) is a key mediator of the inflammatory reactions that are central to the pathogenesis of allergic diseases such as asthma and rhinitis. The recognition of the importance of IgE in allergic disease led to the development of omalizumab, a humanized monoclonal anti-IgE antibody that binds free circulating IgE and prevents the interaction between IgE and high-affinity (FcepsilonRI) and low-affinity (FcepsilonRII) IgE receptors on inflammatory cells. By removing free IgE, omalizumab also markedly downregulates the expression of high-affinity receptors on basophils, mast cells and dendritic cells. Several studies have shown that omalizumab effectively reduces the risk of exacerbations and hospitalization and improves symptom control, lung function and quality of life in patients with severe persistent allergic asthma. Importantly, omalizumab has been shown to be effective in patients with poorly controlled severe persistent allergic asthma, a group of patients with few effective additional treatment options. In addition, omalizumab has been shown to provide effective relief from the symptoms of allergic rhinitis (including patients with concomitant asthma). Patients with uncontrolled severe persistent allergic asthma are a challenging and difficult-to-treat population for whom omalizumab might represent an important new treatment option. In addition, omalizumab may provide a means to address comorbid allergic disease in patients with asthma. Further investigation is also warranted to explore potential applications of omalizumab in occupational asthma.     

Treating moderate-to-severe allergic asthma with anti-IgE monoclonal antibody (omalizumab). An update

Increased asthma severity is not only associated with enhanced recurrent hospitalisation and mortality but also with higher social costs. Most cases of asthma are atopic in nature, with the trigger for acute asthma attacks and chronic worsening of inflammation being allergens inducing an immune response through immunoglobulins of IgE class. Currently antiinflammatory treatments are effective for most of asthma patients, but there are subjects whose disease is incompletely controlled by inhaled or systemic corticosteroids and these patients account for about 50% of the healthcare costs of asthma. Omalizumab is a humanized recombinant monoclonal anti-IgE antibody developed for the treatment of allergic diseases and with clear efficacy in adolescent and adult patients with moderate-to-severe allergic asthma.. The anti-IgE antibody inhibits IgE functions blocking free serum IgE and inhibiting their binding to cellular receptors. By reducing serum IgE levels and IgE receptor expression on inflammatory cells in the context of allergic cascade, omalizumab represents a really new approach to the treatment of atopic asthma. Omalizumab improves quality of life of patients with severe persistent allergic asthma that is inadequately controlled by currently available asthma medications. This therapy is well tolerated and significantly improves symptoms, disease control, reducing asthma exacerbations and the need to use high dosage of inhaled corticosteroids. In other words, omalizumab may fulfil an important need in patients with moderate-to-severe asthma.     

Treating Moderate-to-Severe Allergic Asthma with a Recombinant Humanized Anti-IgE Monoclonal Antibody (Omalizumab)

Bronchial asthma is a chronic inflammatory disease of the airways which is recognized as a highly prevalent health problem in both the developed and the developing world, with significant human and economic consequences.Allergy is acknowledged as a major risk factor for asthma. The pathogenetic aspects of allergic asthma are characterized by airway inflammation with infiltration of mast cells, basophils, eosinophils, monocytes and T helper type 2 lymphocytes, along with the isotype switching of B cells to generate immunoglobulins of the immunoglobulin E (IgE) class. Increased asthma severity is not only associated with recurrent hospitalization and increased mortality but also with higher social costs.Inhaled corticosteroids are the standard anti-inflammatory medication and are effective for most asthma patients, but there is a substantial number of asthmatics who remain symptomatic even after receiving treatment with inhaled corticosteroids and long-acting beta(2)-adrenoceptor agonists (beta(2)-agonists), and sometimes are in need of systemic corticosteroids to control the disease. These patients account for about 50% of the healthcare costs of asthma.New treatment options more specifically targeting the pathophysiologic events causing development of asthma are therefore required in these patients.A novel therapeutic approach to asthma and other allergic respiratory diseases involves interference with the action of IgE and prevention of subsequent IgE-mediated responses.Omalizumab is a humanized recombinant monoclonal anti-IgE antibody developed for the treatment of allergic diseases, with clear efficacy in adolescent and adult patients with moderate-to-severe allergic asthma. This non-anaphylactogenic anti-IgE antibody inhibits IgE functions by blocking free serum IgE and inhibiting their binding to cellular receptors. Omalizumab therapy is well tolerated and significantly improves symptoms and disease control, and reduces asthma exacerbations and the need to use high dosages of inhaled corticosteroids. Moreover, omalizumab improves quality of life of patients with severe persistent allergic asthma that is inadequately controlled by currently available asthma medications. In conclusion, omalizumab may fulfill an important need in patients with moderate-to-severe asthma inadequately controlled with inhaled corticosteroids +beta(2)-agonists.     

What is new in antiimmunoglobulin E asthma therapy.

Omalizumab, a recombinant humanized monoclonal antibody, is the first therapeutic agent specifically targeting immunoglobulin E (IgE). It has been investigated extensively in the treatment of patients with allergic diseases and is approved in the United States for the treatment of patients with moderate-to-severe persistent asthma. In this setting, omalizumab reduced the frequency and incidence of asthma exacerbations and asthma control was well maintained, even though patients significantly reduced their dose of inhaled corticosteroid. Importantly, omalizumab has been shown to reduce asthma exacerbations in high-risk patients (e.g., with previous intubation and hospitalization) and to reduce the level of severe asthma exacerbations (those resulting in emergency treatment and hospitalization). Responder analysis shows that omalizumab provides the greatest benefit in patients with more severe asthma, and this has been confirmed by recent studies establishing the efficacy of omalizumab in patients whose asthma is poorly controlled despite receiving the best standard care in medication. Omalizumab also has proved to be effective in patients with seasonal and perennial allergic rhinitis and to improve quality of life for patients with asthma or rhinitis. As expected with a systemic anti-IgE agent, omalizumab was shown to be effective in the treatment of patients with concomitant asthma and allergic rhinitis. The efficacy of omalizumab in a range of allergic diseases reaffirms the importance of IgE in the pathogenesis of these conditions and establishes the potential benefit to be obtained by inhibiting IgE, especially in patients with more severe and comorbid allergic diseases.     

Targeting immunoglobulin E as a novel treatment for asthma

Omalizumab is a recently developed monoclonal anti-IgE antibody. Clinical trials have demonstrated its efficacy in patients with moderate-to-severe and severe or poorly controlled allergic asthma, in patients with seasonal and perennial allergic disease, and in subjects with concomitant asthma and allergic rhinitis. Patients with more severe asthma appear to obtain the greatest benefit from omalizumab therapy. Omalizumab is well tolerated and has a good safety profile. Anti-inflammatory activity has been shown in both allergic asthma and allergic rhinitis. These results confirm the importance of IgE in allergic disease and support the rationale behind the development of a therapeutic anti-IgE antibody. Omalizumab is a significant addition to current asthma treatments and shows great promise as a therapy for allergic rhinitis, in particular for those patients with concomitant allergic disease.     

Omalizumab. A review of the new treatment of allergic asthma and seasonal allergic rhinitis

The causal role of immunoglobulin E (IgE) in triggering the cascade of biochemical events leading to allergic disease is well established. Treatments that selectively inhibit IgE activity are a logical approach in managing the allergic response. Omalizumab is a recombinant humanised monoclonal antibody which specifically binds to the Cε3 domain of immunoglobulin (Ig) E, the site of high-affinity IgE receptor binding. The clinical benefit and steroid-sparing effect of treatment with the anti-immunoglobulin-E (IgE) antibody, Omalizumab, was assessed in patients with moderate-to-severe allergic asthma and seasonal allergic rhinitis. Intravenous and subcutaneous administration of anti-IgE mAb reduces circulating levels of IgE in atopic patients to low levels commonly seen in non-atopic individuals. Anti-IgE therapy offers protection against allergen-induced bronchoconstriction, reduces the need for short acting inhaled beta 2-agonist and corticosteroids among asthmatic patients and reduces severity of symptoms of allergic rhinitis. Adverse events were infrequent in clinical trials of omalizumab, and not significantly different from placebo. The most frequent drug-related event was mild to moderate urticaria. They do not induce anaphylaxis and the occurrence of antibodies against anti-IgE mAb is sporadic. The results of cited studies suggest that humanized anti-IgE monoclonal antibodies may have important immunotherapeutic benefit for treatment of allergic disorders.     

Anti-IgE in severe persistent allergic asthma

Abstract:   Omalizumab is an mAb targeted against IgE. It reduces asthma exacerbations and symptoms and has low anaphylactic potential. In the placebo-controlled double-blind study, INNOVATE, omalizumab was used in the patient population with the greatest unmet clinical need, who being those meeting the Global Initiative for Asthma 2002 step 4 criteria for severe persistent asthma. When added to existing therapy, patients treated with omalizumab had a 26.2% lower rate of clinically significant asthma exacerbations, after an adjustment to take into account an observed pre-study imbalance in the exacerbation rate ( P  = 0.042). The Global Initiative for Asthma has recognized the role of anti-IgE therapy in treating patients with severe persistent asthma. Initiation of anti-IgE therapy is now recommended for these patients at step 4. Severe asthma has a major impact on health-care resource utilization. To date, treatment options have been limited in this target population. Omalizumab reduces symptoms, exacerbations and emergency visits in patients who are not adequately controlled on inhaled corticosteroids and long-acting beta agonists. It is a valuable therapeutic option, addressing an unmet need in the area of severe asthma.     

Anti-immunoglobulin E, a monoclonal antibody to treat respiratory disorders

Omalizumab is a monoclonal antibody that interrupts allergic reaction--irrespective of the nature of the allergen--by blocking free immunoglobulin E (IgE). The IgE is thus prevented from attaching to cell receptors and setting in motion an allergic cascade of inflammatory mediators. Other interesting biological effects of omalizumab are that it downregulates IgE receptor expression on cell membranes and reduces bronchial eosinophilic infiltration. Clinical trials have demonstrated omalizumab's efficacy and safety in treating most allergic disorders. However, given its high cost, omalizumab is generally reserved for more severe cases of asthma and for asthma that responds poorly to conventional treatments.     

Omalizumab in patients with severe persistent allergic asthma in a real-life setting in Germany

Omalizumab is a humanized monoclonal anti-immunoglobulin E (IgE) antibody indicated in Europe for the treatment of uncontrolled severe persistent allergic (IgE-mediated) asthma despite optimal therapy with inhaled corticosteroids and long-acting β₂ agonists.Between 2005 and 2007 280 patients (58% female, mean age 44 ± 16 yrs., 46% on oral corticosteroids, median serum IgE level 235 IU/ml) who met the EU criteria for add-on therapy with anti-IgE were treated prospectively with omalizumab by 134 physicians as part of a post-marketing surveillance trial and were followed-up for 6 months.The median follow-up time was 195 days, the patients were treated with a median dose of 450 mg omalizumab every 4 weeks. After 6 months there was a marked effect of omalizumab treatment on daily (−76%) and nocturnal symptoms (−84%), exacerbations (−82%), unscheduled health care contacts (−81%), hospitalizations (−78%) and quality of life (Mini-AQLQ: score increase from 2.9 to 4.5). Overall, efficacy of omalizumab was rated as excellent or good by the majority of physicians (82%) and patients (86%). In 19 patients (7%) omalizumab-related adverse events were recorded.This post-marketing surveillance trial confirms the marked and clinically relevant effect of omalizumab on asthma symptoms and level of asthma control in the majority of patients with severe persistent allergic (IgE-mediated) asthma in a real-life situation.     

Effectiveness of Omalizumab in a Patient with Severe Asthma, Low Serum IgE Level, and Lack of Sensitized Allergens Induced by Oral Steroid Therapy: The Usefulness of Impulse Oscillation for Assessment of Omalizumab Therapy

Background. Omalizumab is a humanized monoclonal anti-IgE antibody that was recently approved for the treatment of severe allergic asthma. However, omalizumab is not licensed for allergic asthma in patients with a low serum IgE level (<30 IU/mL) or negative results for specific allergen tests. Case history. We present a patient with severe asthma and low serum IgE levels who had negative results for specific allergens induced by oral steroid therapy. Omalizumab administration improved asthma exacerbated forced expiratory volume in 1 s (FEV(1)) and respiratory resistance measurements based on the impulse oscillation technique (Mostgraph-01). The response to omalizumab therapy was evidenced by a decrease in airway resistance at 1 month. Conclusions. The findings of this case report indicate that omalizumab treatment had beneficial effects in a patient with severe asthma and low total serum IgE levels with negative results for specific IgE, which may have been induced by long-term corticosteroid administration.     

Roles of omalizumab in various allergic diseases

IgE and mast cells play a pivotal role in various allergic diseases, including asthma, allergic rhinitis, and urticaria. Treatment with omalizumab, a monoclonal anti-IgE antibody, has significantly improved control of these allergic diseases and introduced a new era for the management of severe allergic conditions. About 10 years of experience with omalizumab treatment for severe allergic asthma confirmed its effectiveness and safety, reducing symptoms, frequency of reliever use, and severe exacerbations in patients with intractable conditions. Omalizumab is particularly useful in childhood asthma, where atopic conditions often determine clinical courses of asthma.Recently, omalizumab is approved for the treatment of chronic spontaneous urticaria (CSU) with the fixed dose of 300 mg. Although the mechanisms underlying the actions of omalizumab in CSU are not fully clarified, nearly 90% of patients with CSU showed a complete or a partial response to omalizumab treatment. Furthermore, omalizumab is just approved for the treatment of severe Japanese cedar pollinosis (JC) based on the successful results of an add-on study of omalizumab for inadequately controlled severe pollinosis despite antihistamines and nasal corticosteroids. For proper use of omalizumab to treat severe JC, co-administration of antihistamines is necessary, while patients should meet the criteria including strong sensitization to Japanese cedar pollen (≥class 3) and poor control under standard treatment.In the management of severe allergic diseases using omalizumab, issues including cost and concerns about relapse after its discontinuation should be overcome. At the same time, possibilities for application to other intractable allergic diseases should be considered.     

Omalizumab

Omalizumab (Xolair) is a humanized monoclonal antibody used in the treatment of adolescent and adult patients with moderate to severe allergic asthma inadequately controlled with inhaled corticosteroids (ICS). It selectively binds to circulating immunoglobulin E (IgE) and, thereby, prevents binding of IgE to mast cells and other effector cells. Without surface-bound IgE, these cells are unable to recognize allergens, thus preventing cellular activation by antigens and the subsequent allergic/asthmatic symptoms. Omalizumab decreases free serum IgE levels in a dose-dependent manner, reduces IgE receptor density on effector cells, and significantly improves airway inflammation parameters. Omalizumab is slowly absorbed after subcutaneous administration, and mean elimination half-life is 26 days, thus allowing infrequent administration of the drug. Omalizumab dosage is determined by bodyweight and pretreatment serum total IgE levels. Patients treated with subcutaneous omalizumab in clinical trials received a dosage that was approximately equal to 0.016 mg/kg/IgE (IU/mL) per 4 weeks. Thus, patients received 150 or 300 mg every 4 weeks, or 225, 300, or 375 mg every 2 weeks. In adults and adolescents (> or =12 years of age) with moderate to severe allergic asthma, subcutaneous administration of omalizumab as add-on therapy with ICS improved the number of asthma exacerbations, rescue medication use, asthma symptom scores, and quality-of-life (QOL) scores compared with placebo during 28- and 32-week double-blind trials. In addition, concomitant ICS use was significantly decreased in patients receiving omalizumab, and in the two largest double-blind trials approximately 40% of omalizumab recipients completely withdrew from ICS therapy while maintaining effective asthma control. In general, results of extension studies showed that the beneficial effects of omalizumab were maintained over a total period of 52 weeks. Omalizumab was well tolerated as add-on therapy with ICS during treatment for up to 52 weeks. Common adverse events in clinical trials included injection site reaction, viral infection, upper respiratory tract infection, sinusitis, headache, and pharyngitis, although the incidence of adverse events with omalizumab was similar to that with placebo. CONCLUSION: Omalizumab, as add-on therapy with ICS, is an effective and well tolerated agent for the treatment of moderate to severe allergic asthma in adolescents and adults. In addition to its symptomatic and QOL benefits, omalizumab therapy allows ICS dosage reduction or discontinuation of ICS in many patients. Comparisons of omalizumab with other asthma therapies have yet to be conducted; however, clinical efficacy and tolerability data indicate that omalizumab is a valuable option in the treatment of allergic asthma.     

Omalizumab and the treatment of allergic rhinitis

Anti-IgE therapy affects mechanisms in the allergic response that are IgE-dependent or IgE-mediated and common to both allergic asthma and allergic rhinitis. Clinical trials of omalizumab in the treatment of patients with allergic rhinitis or comorbid allergic rhinitis and moderate to severe allergic asthma have recorded significant reductions in symptom severity scores of both conditions. This novel therapy has increased the knowledge base concerning IgE-mediated allergic responses, and, in keeping with its actions established in the treatment of asthma, appears to be useful in the treatment of moderate to severe allergic rhinitis, as well.     

Anti-immunoglobulin E therapy for asthma

The role of immunoglobulin E (IgE) in allergic asthmatic disease is well established. Allergen-specific IgE binds to its cognate receptors, thus triggering a series of cellular events. These events include presentation of antigen by dendritic cells and the degranulation of mast cells and basophils to release numerous factors that play an integral part in potentiating the disease symptoms. Studies in the mouse indicate that a reduction in IgE levels could lead to significant attenuation of the allergic inflammatory response associated with diseases such as asthma, making IgE a target for the development of new therapeutic agents. Omalizumab (Xolair, a recombinant humanized monoclonal anti-IgE antibody that blocks the interaction of IgE with its receptors, is the first anti-IgE agent to undergo clinical development. Several clinical studies have been performed in adults and children with moderate-to-severe allergic asthma to evaluate the efficacy and safety of this agent. Treatment with omalizumab was well tolerated and showed clinical benefit in terms of a reduction in the frequency and number of asthma exacerbation episodes and lower usage of corticosteroids and other medications to control disease, along with improved quality of life. Such findings indicate that omalizumab represents a promising new treatment option for allergic asthma.     

Reduction of the Total IgE Level by Omalizumab in Children and Adolescents

Background: Current data from clinical studies show that patients with severe allergic asthma experience a significant improvement from omalizumab. The early and late allergic reactions are inhibited by formation of complexes with free circulating immunoglobulin E (IgE), independent of which antigen activates the allergic cascade. The dosage of omalizumab depends on body weight and IgE level, yet no parameter has been established to guide dosage changes during therapy. The aim of this study was to investigate the value of the determination of total IgE by ADVIA Centaur assay to monitor the therapy progress. Patients and Methods: Nine patients, 8 to 17 years of age, received therapy with omalizumab due to severe allergic bronchial asthma. In addition, the patients had pronounced rhinoconjunctivitis, food allergy, insect sting allergy, and/or neurodermitis. The total IgE in the serum (Sandwich-Immunoassay ADVIA Centaur) was measured in the patients once monthly before each omalizumab injection as a potential progress parameter. Results: Six months after the beginning of therapy with omalizumab, a significant decrease of the total IgE concentration was found, in comparison to the baseline values (p < 0.01). In all patients, the tolerability of omalizumab was very good; there was a reduction in the frequency of the asthma exacerbations and rescue medications. The dosage of inhaled glucocorticoids could be lowered. All patients reported a clearly improved quality of life. Conclusions: The increase of the total IgE concentrations after administration of omalizumab described in the literature could not be confirmed. The value of total serum IgE as a progress parameter should be investigated in controlled studies with regard to sensitivity and specificity of the respective assays. The establishment of a test procedure for therapeutic monitoring appears urgently necessary, so that the appropriate dosage of omalizumab is applied in children and adolescents. Patients receiving omalizumab therapy should be closely monitored.     

Omalizumab: Anti-IgE Therapy in Allergy

Omalizumab is a humanized, monoclonal anti-IgE antibody that binds specifically to circulating IgE molecules, thus interrupting the allergic cascade. Omalizumab has been shown to be highly effective in treating children and adults with moderate to severe allergic asthma. Beyond this indication, the mode of action itself suggests that omalizumab is not only an antiasthmatic drug but also a promising therapeutic option for various allergic conditions, including allergic rhinitis, food allergy, urticaria, allergic bronchopulmonary aspergillosis, insect hypersensitivity, and atopic dermatitis. However, data from double-blind, placebo-controlled clinical trials are only available for allergic rhinitis and moderate to severe bronchial asthma. The aim of this review is to discuss the current clinical data as well as possible further indications of omalizumab treatment.     

Omalizumab beyond asthma

IntroductionOmalizumab has been demonstrated to be a successful therapy in the management of asthma through reduction of patient's symptoms and use of inhaled corticosteroids. The effect of omalizumab is achieved by immunoglobulin E (IgE) blockage and other secondary mechanisms resulting from this blockage. Because other diseases have an important IgE mediation in their physiopathology, the question arises as to if omalizumab would be useful in the treatment of other IgE-mediated diseases.ObjectiveWe present an overview of the experimental studies and clinical reports evaluating the use of omalizumab in diseases different to asthma including atopic dermatitis, urticaria, eosinophilic gastrointestinal disorders, idiopathic anaphylaxis, latex allergy, hymenoptera venom allergy, and other IgE diseases.MethodsWe reviewed the literature using PUBMED, EMBASE, and LILACS for publications which used omalizumab in the treatment of patients with allergic diseases or any other diseases. Complete articles published in English, Spanish or Portuguese were included.ConclusionThere is not enough evidence to support the regular use of omalizumab in IgE diseases other than asthma. However, some experimental and clinical investigations indicate that omalizumab could be a therapeutic option in several allergic diseases like atopic dermatitis, urticaria, and eosinophilic gastrointestinal disorders. More control studies are needed in each IgE disease to evaluate the efficacy and safety of omalizumab in IgE mediated diseases.     

Asthma exacerbations: pharmacological prevention

Asthma exacerbations are responsible for many emergency medical interventions and account for a significant proportion of the health costs of the disease. Increased airway inflammation is a key feature of exacerbations in asthma and therefore inhaled corticosteroids (ICS) are considered as first-line therapy for long-term asthma control. ICS have been demonstrated to reduce the risk of asthma exacerbations, as well as improving lung function. Oral leukotriene receptor antagonists also reduce the incidence of asthma exacerbations but are less effective than ICS. In patients with inadequately controlled persistent asthma despite low-dose ICS, the addition of a long-acting inhaled beta-agonist (LABA) should be considered. LABA should not be given alone and should always be associated with ICS in asthma. The anti-immunoglobulin E antibody, omalizumab, reduces severe exacerbations and emergency visits in patients with severe allergic asthma. In clinical trials measurement of the inflammatory response in induced sputum could provide information concerning appropriate drug therapy. Asthma-associated comorbidities should be investigated and treated, particularly in severe asthma. Despite a high prevalence of both gastro-oesophageal reflux and allergic rhinitis among patients with asthma, treatment with proton-pump inhibitors or nasal corticosteroids does not reduce the rate of asthma exacerbations.     

Mechanisms of IgE Inflammation

The prevalence of diseases such as allergic asthma and rhinitis continues to increase in the United States, affecting millions of people. It is well-established that allergy contributes to the pathogenesis of most asthma, especially in children and young adults. Despite current therapy (eg, inhaled corticosteroids, anti-leukotrienes, and bronchodilators), patients with moderate to severe asthma remain symptomatic and experience frequent exacerbations of disease requiring oral corticosteroids, emergency department treatments, and hospitalizations. Allergic diseases are traditionally referred to as immediate or type 1 hypersensitivity reactions, with IgE as a critical factor. IgE is involved in allergic inflammation, especially in early-phase response, but it may also be involved in the late-phase allergic response. A direct correlation between serum IgE levels and asthma exists. As logarithm IgE values increase, asthma prevalence increases linearly, even in patients who are categorized as having nonallergic asthma. In addition, there is a significant, although low association in allergic rhinitis with IgE levels and positive skin test reactivity to pollens. Recent advances in our understanding of the role of IgE in allergic inflammation have led to the development of a monoclonal antibody to IgE that reduces IgE levels, thereby reducing allergic inflammation. This review aims to provide an overview of the basic science of the IgE molecule and the clinical efficacy of anti-IgE therapy in allergic and asthmatic diseases.     

Omalizumab (Xolair) improves quality of life in adult patients with allergic asthma: a review

Physicians are increasingly aware that asthma causes significant impairment of the patients physical, psychological, and social well-being. Whilst standard clinical endpoints provide significant information on airway status during treatment, it is important to determine whether such improvements overcome the functional impairment that patients have to deal with on a daily basis. As such, assessment of health-related quality of life (QoL) is an important aspect of asthma management in clinical practice. Omalizumab (Xolair) is a recombinant humanized monoclonal anti-immunoglobulin E (IgE) antibody that represents a new therapeutic approach to IgE-mediated diseases such as allergic asthma. Clinical studies show that omalizumab improves the control of allergic asthma whilst reducing steroid consumption, and enhances long-term disease control in patients with recurrent symptoms. Using established and validated QoL methodology, two placebo-controlled clinical studies in adults with moderate-to-severe allergic asthma have shown that patients treated with omalizumab experience a clinically relevant improvement in all aspects of their asthma-related QoL, changes that were significantly superior to those observed for placebo. Such improvements were apparent when omalizumab was added to existing therapy with inhaled corticosteroids, and maintained during a subsequent steroid-reduction phase. Through effective disease control, omalizumab therefore leads to significant improvements in health-related QoL that are meaningful to patients with allergic asthma.