Co-occurrence of IgE and IgG autoantibodies in patients with chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) pathogenesis shows a complex and still unclear interplay between immunoglobulin (Ig)G- and IgE-mediated autoimmunity, leading to mast cell and basophil degranulation and wheal formation. The objective of this study was to evaluate at the same time IgE- and IgG-reactivity to well recognized and recently reported autoantigens in CSU patients, and to assess the effects of such reactivity on response to the anti-IgE monoclonal antibody omalizumab. Twenty CSU patients underwent omalizumab treatment. Urticaria activity score 7 (UAS7) was recorded at baseline and at different drug administration time-points for categorizing early-, late- or non-responders. At baseline, sera from the 20 patients and from 20 controls were tested for IgE and IgG autoantibodies to high- and low-affinity IgE receptors (FcεRI and FcεRII), tissue factor (TF) and thyroglobulin (TG) by immunoenzymatic methods. Antibody levels were compared with those of controls and analysed according to response. Eighteen patients were omalizumab responders (11 early and seven late), while two were non-responders. More than 50% of patients had contemporary IgE and IgG to at least to one of the four different autoantigens. Late responders showed higher levels of both anti-TF IgE and IgG than early responders (P = 0·011 and P = 0·035, respectively). Twenty-five per cent of patients had levels of anti-FcεRI IgE, exceeding the upper normal limit, suggesting that it could be a novel auto-allergen in CSU. In CSU, there is an autoimmune milieu characterized by the co-existence of IgE and IgG autoantibodies to the same antigen/allergen, particularly in late responders to omalizumab, possibly explaining the slower response.     

Predicting development of sustained unresponsiveness to milk oral immunotherapy using epitope-specific antibody binding profiles

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Safety of anti-immunoglobulin E therapy with omalizumab in allergic patients at risk of geohelminth infection

BACKGROUND: Although the role of immunoglobulin E (IgE) in immunity against helminth parasites is unclear, there is concern that therapeutic antibodies that neutralize IgE (anti-IgE) may be unsafe in subjects at risk of helminth infection. OBJECTIVE: We conducted an exploratory study to investigate the safety of omalizumab (anti-IgE) in subjects with allergic asthma and/or perennial allergic rhinitis at high risk of intestinal helminth infection. The primary safety outcome was risk of infections with intestinal helminths during anti-IgE therapy. METHODS: A randomized, double-blind, placebo-controlled trial was conducted in 137 subjects (12-30 years) at high risk of geohelminth infection. All subjects received pre-study anthelmintic treatment, followed by 52 weeks' treatment with omalizumab or placebo. RESULTS: Of the omalizumab subjects 50% (34/68) experienced at least one intestinal geohelminth infection compared with 41% (28/69) of placebo subjects [odds ratio (OR) 1.47, 95% confidence interval (CI) 0.74-2.95, one-sided P=0.14; OR (adjusted for study visit, baseline infection status, gender and age) 2.2 (0.94-5.15); one-sided P=0.035], providing some evidence for a potential increased incidence of geohelminth infection in subjects receiving omalizumab. Omalizumab therapy was well tolerated, and did not appear to be associated with increased morbidity attributable to intestinal helminths as assessed by clinical and laboratory adverse events, maximal helminth infection intensities and additional anthelmintic requirements. Time to first infection (OR 1.30, 95% CI 0.79-2.15, one-sided P=0.15) was similar between treatment groups. Infection severity and response to anthelmintics appeared to be unaffected by omalizumab therapy. CONCLUSIONS: In this exploratory study of allergic subjects at high risk of helminth infections, omalizumab therapy appeared to be safe and well tolerated, but may be associated with a modest increase in the incidence of geohelminth infection.     

奥马珠单抗治疗变应性鼻炎疗效与安全性的Meta分析

目的系统分析奥马珠单抗治疗难治型变应性鼻炎的疗效及安全性。方法通过搜索PubMed,Cochrane Library,CNKI及万方数据库,收集奥马珠单抗治疗难治型变应性鼻炎的随机对照试验(RCT),使用Revman 5.3软件对数据进行Meta分析,评价奥马珠单抗的疗效及安全性。结果 Meta分析结果显示,奥马珠单抗在降低鼻部症状方面差异有统计学意义,药物引起的不良反应差异无统计学意义。结论奥马珠单抗在缓解鼻部症状等方面具有显著的效果,是一种相对安全的药物。     

Case study: A Combination of Mepolizumab and Omaluzimab injections for severe asthma

A Combination of Mepolizumab and Omaluzimab injections for severe asthma. Introduction. Patients with severe persistent asthma account for a large proportion of asthma morbidity and health care expenditures. In this case report we describe the use of a combination of omalizumab and mepolizumab in severe asthma with elevated IgE levels and eosinophilic phenotype. Case Study: We are treating a 55 year old woman with severe persistent eosinophilic asthma and elevated IgE levels. Her regimen included salmeterol/fluticasone propionate inhaler 500/50 one puff twice a day, budesonide nebulizer twice a day, tiotropium respimat inhaler two puffs daily, montelukast 10 mg daily, Albuterol as needed, Azithromycin 250 mg three times a week, and also omalizumab injections. She was having recurrent asthma exacerbations requiring the use of oral corticosteroids. Due to frequent exacerbations, we referred her for Bronchial Thermoplasty. This procedure was denied by insurance and therefore the patient was started on 20 mg PO prednisone daily. Mepolizumab was added approximately 4 months after starting chronic PO prednisone. We were able to taper down the steroids and she is currently on 4 mg daily. Results: Since we added the mepolizumab injections along with the omalizumab injections, we have been able to decrease the prednisone steadily and currently the patient is on 4 mg daily. The plan is to taper off the corticosteroids slowly as the clinical status allows. Conclusion: Combination of omalizumab and mepolizumab could become the gold standard for severe asthma patients that have elevated IgE levels and an eosinophilic phenotype. Case Report: A Combination of Mepolizumab and Omaluzimab injections for severe asthma.     

Targeted therapy for allergic asthma: predicting and evaluating response to omalizumab

Evaluation of: Bousquet J, Rabe K, Humbert M et al. Predicting and evaluating response to omalizumab in patients with severe allergic asthma. Respir. Med. 101(7), 1483–1492 (2007).

Among new asthma therapies, omalizumab is the only monoclonal antibody that has been proven to be effective and safe in treating severe, inadequately controlled asthma. Nevertheless, it has been pointed out that not all patients respond to it. This paper analyzes the results of a recent study that was aimed at achieving a more accurate evaluation of the response to omalizumab in patients with severe allergic asthma, by identifying possible pretreatment characteristics that can be predictive of a better and superior response to omalizumab. The results established that it is difficult to predict which patients will gain most benefit from treatment, according to pretreatment baseline characteristics.     

Biological therapies for eosinophilic asthma

Introduction: Severe uncontrolled asthma is by definition refractory to traditional therapies or can be controlled only with therapies that have intolerable side effects. Monoclonal antibodies that target interleukin (IL)-5/IL-5Rα, IgE, and IL-4Rα have shown favorable results in clinical trials, including reductions in asthma exacerbations and other important clinical outcomes. These biological agents offer treatment alternatives to patients with uncontrolled severe eosinophilic asthma.

Areas covered: This article reviews how the shifting emphasis toward identifying distinct asthma phenotypes has led to the approval of biological therapies that preferentially benefit patients with severe eosinophilic asthma. The clinical trials that led to the approval of these biologic treatments are discussed in detail.

Expert opinion: Biologic therapies targeting the IL-5, IgE, IL-4/IL-13 signaling pathways have been successful in clinical trials in subjects with severe eosinophilic asthma. Some of these agents have also been successful regardless of peripheral blood eosinophil counts. These treatments have shown a relatively favorable safety profile in clinical trials, although long-term safety data for some of these agents are limited. Due to the high costs associated with these medications, they should be reserved for select patients where they yield a therapeutic and pharmacoeconomic advantage.