Omalizumab decreased IgE-release and induced changes in cellular immunity in patients with allergic asthma

A pilot study towards the immunological effects of omalizumab treatment used to facilitate oral immunotherapy in peanut-allergic adolescents

Anti-IgE treatments, such as omalizumab, have shown promising effects in allergy treatment. Our previous work has shown that individualized omalizumab treatment (OT) allows a safe initiation and rapid up-dosing of peanut oral immunotherapy (OIT) in peanut-allergic adolescents. However, the broader immunological effects of this OT are incompletely understood. In this pilot study, we longitudinally followed the total B- and T-cell immunity during OT, using flow cytometry, ELISpot and ELISA. Peripheral blood mononuclear cells (PBMCs) and plasma were collected from participants (n = 17) at several timepoints during treatment, before starting OT (baseline), prior to starting OIT during OT (start OIT) and at maintenance dose OIT prior to OT reduction (maintenance). OT did not affect the total B-cell compartment over treatment time, but our results suggest an association between the OT dosage scheme and the B-cell compartment. Further, in vitro polyclonal T-cell activation at the different timepoints suggests a cytokine skewing towards the Th1 phenotype at the expense of Th2- and Th9-related cytokines during treatment. No differences in the frequencies or phenotype of regulatory T cells (Tregs) over treatment time were observed. Finally, plasma chemokine levels were stable over treatment time, but suggest elevated gut homing immune responses in treatment successes during the treatment as compared to treatment failures. The novel and explorative results of this pilot study help to improve our understanding on the immunological effects of OT used to facilitate OIT and provide guidance for future immunological investigation in large clinical trials.

Mabs for treating asthma: omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab

The introduction of biologics for the treatment of patients with refractory asthma represented a marked therapeutic advance. For more than 10 y, the only biologic available has been the monoclonal anti-IgE antibody omalizumab, reserved for patients with asthma caused by perennial allergen. In recent years, other biologics have been licensed for the treatment of severe eosinophilic asthma. They include monoclonal antibodies that target the Th2-pathway cytokines, such as IL-5 (mepolizumab and reslizumab) or its receptor (benralizumab) and the IL-4 and IL-13 receptor (dupilumab). The effectiveness of these biologics was demonstrated in several placebo controlled trials, the main outcomes being the significant reduction of the rate of asthma exacerbation and the improvement of respiratory function in actively treated patients. Based on the further understanding of the pathogenesis of asthma, new cytokines network and new targets are emerging, such as thymic stromal lymphopoietin, which can activate Th2 cells, innate lymphoid cells, or both, or prostaglandin D2 (PGD2), to develop additional biologics.

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.

Omalizumab dampens type 2 inflammation in a group of long-term treated asthma patients and detaches IgE from FcεRI

Even if omalizumab is broadly used in the treatment of severe, allergic asthma, the immunological effects in long-term treated patients have not been fully elucidated. To this aim, a cohort of 15 allergic asthmatic patients treated with omalizumab for at least three years was compared with 12 allergic asthma patients treated with standard therapy. Omalizumab treated asthmatic patients showed lower frequencies of circulating plasmacytoid DCs, and lower CD154 expression on CD4 T-helper cells than the control group. Moreover, basophils and DCs from omalizumab-treated patients had lower surface expression of IgE compared to the control group. In a longitudinal evaluation of two patients that started omalizumab treatment, we show that FcεRI free of IgE were evident on basophils just after four weeks of drug administration. Finally, in vitro experiments with basophils obtained from healthy donors confirm that omalizumab is able to detach IgE from high affinity IgE receptors. Collectively these data indicate that long-term omalizumab treatment dampens type 2 inflammation acting on different cell types that play a pivotal role in the pathogenesis of allergic asthma. Moreover, we have identified a further mechanism of action of omalizumab, such as the ability to detach IgE from its receptor.

Monitoring of omalizumab therapy in children and adolescents

BACKGROUND

Omalizumab is a successfully implemented supplementary therapy for improving asthma control in children aged 6 years and older with severe persistent allergic asthma. The dosage of omalizumab depends on body weight and IgE level, yet no parameter has been established to guide dosage changes during therapy. Clinical studies in patients with allergic asthma or allergic rhinitis revealed a clinically relevant improvement by using omalizumab leading to concentrations of free serum IgE reported to be lower than 50 ng/ml. Therefore, only the question concerning the concentrations of free IgE used in a therapy with omalizumab is regarded of clinical importance, while total IgE (free and omalizumab-bound IgE) increases during treatment.

PATIENTS AND METHODS

Ten patients, 8 to 17 years of age, received therapy with omalizumab due to severe allergic asthma. In addition, the patients had pronounced rhinoconjunctivitis, food allergy, insect sting allergy, and/or neurodermitis. The total IgE in the serum was measured in the patients 3 - 6 months before each omalizumab injection as a potential progress parameter (Sandwich-Immunoassay ADVIA Centaur).

RESULTS

Six months after beginning of the therapy with omalizumab, a significant decrease of the total IgE concentration was found, in comparison to the baseline values (p < 0.003). In all patients the tolerability of omalizumab was very good: there was a reduction in the frequency of the asthma exacerbations and rescue medications. All patients reported a clearly improved quality of life.

CONCLUSIONS

A general increase in IgE was not observed in any of the children we treated with omalizumab. Apart from the development of routine assays to determine free serum IgE levels, the significance of the total serum IgE as a suitable control of an omalizumab therapy should be further investigated in controlled studies with regard to sensitivity and specificity. In order to only administer the lowest necessary dose of omalizumab especially in children and adolescents, the establishment of laboratory parameters (free IgE and/or total IgE) to adequately monitor the therapy is urgently needed. Patients undergoing an omalizumab therapy require medical supervision at close intervals.

Use of biomarkers to identify phenotypes and endotypes of severeasthma

OBJECTIVE

Severe asthma can be classified into phenotypes and endotypes, which may inform clinicians about inflammatory pathways leading to disease and ultimately guide optimal therapeutic strategy. Biomarkers, objectively measurable characteristics of the disease, are of increasing interest to clinicians and researchers as powerful tools to distinguish among the severe asthma phenotypes and endotypes. The objective of this review is to highlight current knowledge of biomarker applications to identify phenotypes and endotypes of severe asthma.

DATA SOURCES

Sources used include observational cohorts, clinical trials, translational studies, comprehensive reviews, and expert/taskforce statements.

STUDY SELECTIONS

Included studies were selected for their relevance to the topic and for strength of data or study design.

RESULTS

In severe asthma, biomarkers can be used for diagnosis of phenotype or endotype, can also be predictive of clinical outcomes or response to therapy, and may be dynamic with time or therapy. Fully determining phenotype or endotype of severe asthma will require interpretation of combinations of commercially available biomarkers.

CONCLUSION

Biomarkers have multiple potential clinical applications in severe asthma. Novel biomarkers may add accuracy to this field.

[Omalizumab: Beyond anti-IgE properties]

INTRODUCTION

Omalizumab is used as a treatment for severe allergic asthma. Its intended mechanism of action is based on its anti-IgE proprieties. However, recent studies have highlighted other mechanisms of action.

STATE OF THE ART

Omalizumab treatment is associated with a decrease in the number of dendritic cells, T and B lymphocytes and eosinophils. This anti-inflammatory activity is characterized by a decrease in the levels of several cytokines involved in the recruitment, activation and survival of eosinophils and mastocytes, and in a Th2 orientation of the immune response. A modulation of bronchial remodeling by omalizumab has recently been shown. A decrease in the production of extracellular matrix components and in the proliferation of smooth muscle cells could be involved in this modulation. These mechanisms of action could explain in part the clinical efficiency of omalizumab in non-allergic conditions such as non-allergic asthma, non-allergic urticaria or nasal polyposis.

CONCLUSION

A precise knowledge of the mechanisms of action of omalizumab could allow the identification of biomarkers predictive of efficacy of this treatment. These could be useful tools in the phenotyping of severe asthma.

Optimisation of omalizumab dosage in patients with severe persistent allergic asthma using recoveryELISA

BACKGROUND

The objective of this study was to investigate the suitability of recoveryELISA as a method to monitor treatment with therapeutic antibodies using the example of omalizumab.

METHODS

The recoveryELISA is a newly developed immunoassay technology that measures three parameters in one test: the free level of antigen, the level of therapeutic antibody and the specific dose-response interaction which represents the actual activity of the drug. A retrospective and observational analysis was performed on 197 serum samples from 17 patients (13 ± 4 years of age) with severe persistent allergic asthma who received add-on treatment with omalizumab.

RESULTS

The mean omalizumab serum level during antibody therapy was 59 ± 45 µg/mL; the kit's upper detection limit of 140 µg/mL was exceeded in 27 samples. Antibody concentrations between 50 and 140 µg/mL were found in 64 samples. Independent of the omalizumab dosage, nearly all measurements were in a range of absolute saturation as regards the IgE binding rate. Almost complete binding of IgE with a recovery of added labelled IgE of <1% was reached within a maximum of 11 days.

CONCLUSIONS

The biochemical activity of therapeutic antibodies can be examined by recoveryELISA and their residual activity can be determined. Thus, further individualisation of therapy with biologics is possible using this test which seems to be suitable to diminish side effects and reduce costs.

Changes in blood eosinophilia during omalizumab therapy as a predictor of asthma exacerbation

INTRODUCTION

Omalizumab is a monoclonal anti-immunoglobulin E antibody developed for the treatment of severe allergic asthma. The number of exacerbations used as a parameter of omalizumab therapy efficacy may be insufficient in many cases due to a relatively short time to first evaluation (16 weeks). Therefore, it is advisable to look for parameters of more prognostic value while continuing omalizumab therapy.

AIM

To evaluate usefulness of analysis of changes of blood eosinophilia after 16 weeks of omalizumab therapy as a predictor of asthma exacerbations.

MATERIAL AND METHODS

The study was conducted on a group of 13 patients with severe persistent allergic asthma treated with omalizumab. Blood eosinophil counts were measured before and after 16 weeks of anti-IgE therapy. On the basis of percentage of eosinophilia decrease (> 50% or < 50% of the initial value), patients were divided into two groups. Analysis of the asthma exacerbation rate during 12 months and time to first exacerbation was performed.

RESULTS

In the group with a high decrease in blood eosinophil counts (group 1) we showed a statistically significantly lower asthma exacerbation rate in 12 months compared with the group with a low decrease in blood eosinophil counts (group 2) (p = 0.02). We also observed the tendency to longer time to first asthma exacerbation in group 1 compared to group 2 (p = 0.06).

CONCLUSIONS

Our results showed that a decrease in blood eosinophilia during omalizumab therapy can be a predictor of asthma exacerbation. Evaluation of changes in blood eosinophil count should be taken into the consideration while estimating response to anti-IgE therapy in patients with severe allergic asthma.

Omalizumab treatment in brittle asthma

Asthma is a heterogeneous disease with variable characteristics such as lung function, symptoms and control, body weight, pattern of inflammation, and response to treatment. Brittle asthma is one of clinical phenotypes of asthma with unclear pathogenic mechanisms and appropriate treatment. Analysis of 2 described cases suggests that omalizumab could be useful in the treatment of brittle allergic asthma.

Omalizumab may decrease IgE synthesis by targeting membrane IgE+ human B cells

Background

Omalizumab, is a humanized anti-IgE monoclonal antibody used to treat allergic asthma. Decreased serum IgE levels, lower eosinophil and B cell counts have been noted as a result of treatment. In vitro studies and animal models support the hypothesis that omalizumab inhibits IgE synthesis by B cells and causes elimination of IgE-expressing cells either by induction of apoptosis or induction of anergy or tolerance.

Methods

We examined the influence of omalizumab on human tonsillar B cell survival and on the genes involved in IgE synthesis. Tonsillar B cells were stimulated with IL-4 plus anti-CD40 antibody to induce class switch recombination to IgE production in the presence or absence of omalizumab. Cell viability was assessed and RNA extracted to examine specific genes involved in IgE synthesis.

Conclusions

We found that omalizumab reduced viable cell numbers but this was not through induction of apoptosis. IL-4R and germline Cϵ mRNA levels were decreased as well as the number of membrane IgE+ cells in B cells treated with omalizumab. These data suggest that omalizumab may decrease IgE synthesis by human B cells by specifically targeting membrane IgE-bearing B cells and inducing a state of anergy.

Anti-immunoglobulin e therapy

The importance of immunoglobulin E (IgE) in atopic disorders such as asthma, allergic rhinitis, food allergies, and atopic dermatitis is well established. Elevation of total serum IgE is typically found in many atopic patients, and in predisposed individuals, allergen-specific IgE is produced. The availability of humanized monoclonal antibodies against IgE has provided a new therapeutic option and tool to explore the role IgE in allergic diseases and the effects of inhibiting IgE itself. Omalizumab is a humanized, monoclonal antibody that recognizes and binds to the Fc portion of the IgE molecule. Administration of omalizumab results in a rapid and substantial decrease in free IgE in serum. Consequently, the activity of cell populations involved in allergic inflammation, including mast cells, eosinophils, basophils, and antigen-presenting cells, is affected as well. Clinically, anti-IgE therapy has already been proven to be useful in the treatment of asthma and allergic rhinitis. The aim of this review is to provide an overview of the mechanisms of action of anti-IgE therapy as well as its efficacy in the treatment of allergic diseases, especially asthma. Considerations regarding dosing and safety of omalizumab will be addressed as well.

Omalizumab decreases IgE production in patients with allergic (IgE-mediated) asthma; PKPD analysis of a biomarker, total IgE

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Omalizumab is a humanized anti-IgE monoclonal antibody that binds and captures circulating IgE, preventing interaction with receptors on mast cells and basophils, thereby interrupting the allergic cascade. It has a well-characterized efficacy and safety profile in patients with asthma. While omalizumab is known to reduce serum free IgE concentrations, effects on total IgE and IgE production are less well characterized.

WHAT THIS STUDY ADDS

(i) Confirmation of prior hypotheses that IgE production can decrease with time when patients are given anti-IgE therapy; (ii) guidance on a biomarker, total IgE, which can be used to ascertain whether individual patients experience a change in their IgE production; and (iii) a way to assess whether patients' IgE production has been sufficiently down-regulated such that they may consider stopping anti-IgE therapy.

AIM

To determine whether excessive IgE production by patients with atopic allergic asthma decreases with omalizumab therapy.

METHODS

Omalizumab, free and total IgE data were obtained from an epidemiological study and six randomized, double-blind, placebo-controlled trials in patients with allergic asthma. The binding between omalizumab and IgE together with the production and elimination of IgE were modelled as previously, except that, in order to explain why total IgE was decreasing over a period of 5 years, the expression of IgE was allowed to change.

RESULTS

The prior constant IgE production model failed to converge on the data once long-term observations were included, whereas models allowing IgE production to decrease fitted. A feedback model indicated that, on average, IgE production decreased by 54% per year. This model was further developed with covariate searches indicating clinically small but statistically significant effects of age, gender, body mass index and race on some parameters. Model predictions were checked internally and externally against 3-5 year data from paediatric and adult atopic asthmatic patients and externally against extensive total IgE data from a long-duration (>1 year) phase 1 study which was not used in the model building.

CONCLUSIONS

A pharmacokinetic-pharmacodynamic model incorporating omalizumab-IgE binding and feedback for control of IgE production indicates that omalizumab reduces production of IgE. This raises the possibility that indefinite treatment may not be required, only for perhaps a few years. After the initial accumulation, total IgE should provide a means to monitor IgE production and guide individual treatment decisions.

IL-8, IL-10, TGF-β, and GCSF levels were increased in severe persistent allergic asthma patients with the anti-IgE treatment

BACKGROUND

Allergic asthma is showed an increase in Th2-cytokine and IgE levels and an accumulation activation of Th2 cells, eosinophils and mast cells. However, recent studies focused on cell-based mechanisms for the pathogenesis of allergic asthma. Objectives. In this study, we compare the anti-IgE treatment modality in the dynamics of immune system cytokine levels in severe persistent asthma (SPA) patients who had no other any allergic disease, newly diagnosed allergic asthma patients and healthy volunteers.

STUDY DESIGN

The study population consisted of 14 SPA patients, 14 newly diagnosed allergic asthma patients and 14 healthy volunteers included as controls. Cytokine levels were measured. Total and specific IgE levels of anti-IgE monoclonal antibody treated patients, serum high-sensitivity C-reactive protein (hsCRP) levels, FEV1/FVC rates and asthma control test (ACT) were measured for the clinical follow-up.

RESULTS

We observed that SPA patients presented increasing levels of IL-8, IL-10, TGF-β and GCSF during the anti-IgE treatment in period of sampling times at 4 months and 18 months. However this increase was not correlated neither with serum hsCRP levels nor FEV1/FVC rates.

CONCLUSIONS

Our study gives a different perspective for the SPA and anti-IgE immunotherapy efficacy at the cell cytokine-linked step.

[Guideline-adherent treatment for asthma]

Asthma is a complex syndrome with numerous clinical phenotypes. An increase in prevalence is detectable worldwide. Efforts to optimize diagnosis and care of patients with asthma have led to the development of international and national guidelines. Besides preventive and non-pharmacological measures such as patient education and physical training, the guidelines particularly recommend standardized drug therapy. In the present article we summarize the recommended pharmacotherapy for patients with bronchial asthma.

A high-affinity monoclonal anti-IgE antibody for depletion of IgE and IgE-bearing cells

BACKGROUND

We have identified a monoclonal anti-human immunoglobulin E (IgE) antibody, which recognizes FcepsilonRI-bound IgE and prevents binding of IgE to FcepsilonRI. In this study, we assessed the binding kinetics and affinity of monoclonal antibody 12 (mAb12) for IgE and investigated whether mAb12 can be used for depletion of IgE and isolation of IgE-bearing cells from peripheral blood.

METHODS

Binding kinetics and affinity for IgE were studied using Biacore surface plasmon resonance technique experiments. IgE antibodies were depleted from serum using sepharose-coupled mAb12 and IgE-bearing cells were enriched from heparinized blood samples with mAb12. The extent and biological relevance of IgE depletion were studied by quantitative IgE measurements and basophil histamine release experiments. Specific binding of mAb12 to IgE-bearing cells (basophils, mast cells, IgE-secreting plasma cells) was demonstrated by FACS.

RESULTS

Monoclonal antibody 12 shows rapid association (k(a) = 5.46e5/Ms) with IgE, almost no dissociation (k(d) = 8.8e-5/s) and an affinity for IgE (K(D) = 1.61e-10 M), which is as high as that of FcepsilonRI. Immobilized mAb12 could be used to deplete IgE antibodies and isolate IgE-bearing cells from peripheral blood in a single-step procedure.

CONCLUSIONS

Monoclonal antibody 12 is a high affinity anti-human IgE antibody, which efficiently removes IgE and IgE-bearing cells from peripheral blood and may thus be used for extracorporeal depletion of IgE and IgE-bearing cells.

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.

Basophil histamine release decreases during omalizumab therapy in allergic asthmatics

BACKGROUND

Omalizumab is an established add-on therapy efficacious in allergic diseases with additional anti-inflammatory activity in the treatment of asthma. The evaluation of responders to anti-IgE treatment is critical to maximize benefit/risk/cost ratio. The aim of the study was to monitor the efficacy of anti-IgE treatment by ex vivo basophil histamine release.

METHODS

Seventeen patients with allergic asthma were enrolled and received omalizumab at a dose of > or =0.016 mg/kg/IgE every 4 weeks. Histamine release from basophils was evaluated fluorometrically after dose-dependent allergen challenge at baseline and after 16 weeks of treatment. Maximal histamine release and cellular sensitivity to the allergen were calculated. Clinical measurements consisted of body plethysmography, skin prick test, beta2-agonist usage, serum free IgE levels, peripheral eosinophils and investigator ratings of global evaluation of treatment effectiveness.

RESULTS

Maximal histamine release and cellular sensitivity to the allergen were significantly decreased in the omalizumab group compared to placebo. These changes were accompanied by significant changes in the clinical markers airway resistance, beta-agonist usage, skin prick test wheal area and investigator ratings of global evaluation of treatment effectiveness.

CONCLUSIONS

Omalizumab therapy decreases basophil histamine release and cellular sensitivity with high effectivity of 95.8% (median). The decline of ex vivo basophil responses does not always parallel individual clinical improvement. Basophil-based stimulation tests should be further evaluated before being regarded as useful parameters monitoring omalizumab therapy.

Omalizumab is more effective than suplatast tosilate in the treatment of Japanese cedar pollen-induced seasonal allergic rhinitis

BACKGROUND

Seasonal allergic rhinitis (SAR) induced by Japanese cedar pollens is a major problem in Japan. Omalizumab, a humanized monoclonal anti-IgE antibody, improves symptoms associated with SAR, but a comparative study with an anti-allergy drug has not yet been conducted.

OBJECTIVE

To compare the efficacy and safety of omalizumab with suplatast tosilate, a selective T-helper type 2 (Th2) cytokine inhibitor, in patients with Japanese cedar pollen-induced SAR.

METHODS

A randomized, double-blind, double-dummy study was conducted in 308 Japanese patients with a history of moderate-to-severe SAR who showed a CAP-RAST value (> or =2+) specifically to Japanese cedar pollens. Patients were treated for 12 weeks with omalizumab plus placebo of suplatast tosilate or suplatast tosilate plus placebo of omalizumab.

RESULTS

The mean daily nasal symptom medication scores (sum of the daily nasal symptom severity score and daily nasal rescue medication score) were significantly lower in the omalizumab group than in the suplatast tosilate group during three evaluation periods (P<0.001). The omalizumab group also had significantly lower mean daily nasal severity scores, each of the mean daily nasal and ocular symptom severity scores (sneezing, runny nose, stuffy nose, itchy nose, itchy eyes, watery eyes, and red eyes). Omalizumab reduced rescue medication requirements, and the proportion of days with any rescue medication use in the omalizumab group was significantly lower. Serum-free IgE levels markedly decreased in the omalizumab group and it was associated with clinical efficacy. The adverse reaction profiles were similar between the two groups. The overall incidence of injection site reactions was higher in the omalizumab group than in the suplatast tosilate group, but all these events were of mild degree. No anti-omalizumab antibodies were detected.

CONCLUSION

Omalizumab showed significantly greater improvements than suplatast tosilate in the treatment of SAR induced by Japanese cedar pollens.