Omalizumab Effectiveness in Severe Allergic Asthma with Multiple Allergic Comorbidities: A Post-Hoc Analysis of the STELLAIR Study

Does Comorbid Food Allergy Affect Response to Omalizumab in Patients with Asthma?

Background

The intrinsic link between food allergy and asthma is well-established, and comorbidity can exacerbate both conditions. Omalizumab, an anti-immunoglobulin E (IgE) antibody, has the biological plausibility to manage both conditions, but only a few small studies have assessed omalizumab in patients with comorbid asthma and food allergy.

Patients and Methods

We conducted a post hoc analysis of placebo-controlled, randomized clinical trials (IA05 in children and 008/009 in adolescents/adults) and real-world observational studies (EXCELS and PROSPERO). For each study, patients with asthma were stratified by whether they had physician-reported food allergy, as per baseline characteristics data.

Results

For patients with comorbid food allergy, there was evidence for increased atopy at baseline (numerically higher total IgE levels and atopic comorbidities). The collective body of evidence found that omalizumab consistently improved general and asthma-specific patient-centered outcomes (food allergy-specific outcomes were not available). For patients with asthma, omalizumab improved healthcare resource use (emergency room visits, hospitalizations, unscheduled doctor visits), quality of life (asthma-specific Asthma Quality of Life Questionnaire), productivity (missed work/school days and the Work Productivity and Activity Impairment: Asthma), and asthma outcomes (asthma exacerbations and Asthma Control Test score) regardless of comorbid food allergy.

Conclusion

There was no loss of omalizumab efficacy even though patients with both asthma and food allergy appeared to be generally more atopic. Omalizumab may be a viable management option for patients with these comorbidities.

Clinical trial registration

NCT00079937; NCT01922037; NCT00252135.

[Unmet Needs in Severe Allergic Asthma]

Severe asthma affects 3%-10% of the world's population, according to estimates by the Global Initiative for ASTHMA (GINA). Allergic asthma is one of the most common phenotypes of severe asthma and it is characterized by allergen-induced type 2 inflammation in which immunoglobulin E (IgE) is a key mediator, making it an important therapeutic target. The introduction of targeted biological therapies or treatments has entered the management for severe asthma in the era of precision medicine, and the goal of treatment is clinical remission of the disease. There is a significant percentage of patients with severe allergic asthma who do not respond to treatments and whose symptoms are not controlled. In this paper, a group of experts in the management of severe allergic asthma reviewed and evaluated the most relevant evidence regarding the pathophysiology and phenotypes of severe allergic asthma, the role of IgE in allergic inflammation, allergen identification, techniques, biomarkers and diagnostic challenges, available treatments and strategies for disease management, with a special focus on biological treatments. From this review, recommendations were developed and validated through a Delphi consensus process with the aim of offering improvements in the management of severe allergic asthma to the professionals involved and identifying the unmet needs in the management of this pathology.

Omalizumab is effective for a patient with pollen-food allergy syndrome who experienced intractable lip edema

Pollen-food allergy syndrome (PFAS) is an immunoglobulin E (IgE)-mediated allergic reaction caused when patients with pollen allergy ingest food having cross-reactivity with pollen. To date, no effective treatment method for this has been established. Here we report the case of a patient with PFAS who experienced lip edema, causing difficulties in treatment. This report describes the case of a 12-year-old boy with perennial allergic rhinitis since the age of 8 years. After ingesting fresh fruits and raw vegetables at the age of 11 years, he started to experience lip edema repeatedly. Thus, the patient was referred to our department. Based on the results of serum antigen-specific IgE, prick-to-prick, and allergen component tests, he was diagnosed with PFAS. He has been instructed to avoid causative food. Furthermore, the treatment using an antihistamine and antileukotriene receptor antagonist was initiated for pollen allergy. Sublingual immunotherapy (SLIT) for Japanese cedar pollen was initiated because the patient experienced severe nasal allergy symptoms during the dispersal season of this pollen. These treatments alleviated the nasal symptoms; however, the lip edema persisted. Omalizumab administration improved the lip edema. The combination of SLIT and omalizumab may be an effective treatment option for patients with PFAS.

Regulation of Trafficking and Signaling of the High Affinity IgE Receptor by FcεRIβ and the Potential Impact of FcεRIβ Splicing in Allergic Inflammation

Mast cells are tissue-resident immune cells that function in both innate and adaptive immunity through the release of both preformed granule-stored mediators, and newly generated proinflammatory mediators that contribute to the generation of both the early and late phases of the allergic inflammatory response. Although mast cells can be activated by a vast array of mediators to contribute to homeostasis and pathophysiology in diverse settings and contexts, in this review, we will focus on the canonical setting of IgE-mediated activation and allergic inflammation. IgE-dependent activation of mast cells occurs through the high affinity IgE receptor, FcεRI, which is a multimeric receptor complex that, once crosslinked by antigen, triggers a cascade of signaling to generate a robust response in mast cells. Here, we discuss FcεRI structure and function, and describe established and emerging roles of the β subunit of FcεRI (FcεRIβ) in regulating mast cell function and FcεRI trafficking and signaling. We discuss current approaches to target IgE and FcεRI signaling and emerging approaches that could target FcεRIβ specifically. We examine how alternative splicing of FcεRIβ alters protein function and how manipulation of splicing could be employed as a therapeutic approach. Targeting FcεRI directly and/or IgE binding to FcεRI are promising approaches to therapeutics for allergic inflammation. The characteristic role of FcεRIβ in both trafficking and signaling of the FcεRI receptor complex, the specificity to IgE-mediated activation pathways, and the preferential expression in mast cells and basophils, makes FcεRIβ an excellent, but challenging, candidate for therapeutic strategies in allergy and asthma, if targeting can be realized.

Efficacy and Safety of Omalizumab for the Treatment of Severe or Poorly Controlled Allergic Diseases in Children: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate the efficacy and safety of omalizumab in the treatment of severe or uncontrolled allergic diseases in children.

METHODS

We conducted a systematic search of the PubMed, Embase, CENTRAL, and clinicaltrials.gov databases up to 23rd July 2021, with no language limitations. Randomised controlled trials (RCTs) comparing omalizumab with other treatments or placebo in children with severe or inadequately controlled allergic diseases were considered. The primary outcomes of interest were asthma exacerbation rate, allergic symptom score, desensitisation achievement for food allergy (FA), and incidence of serious adverse events (SAEs). The study selection and data extraction were conducted independently by two researchers. Quality assessments were conducted using the Cochrane risk-of-bias tool, and data were pooled using a random-effects model if I ² was 50% or greater in the Cochrane Review Manager.

RESULTS

Overall, 10 RCTs [six on severe asthma, one on atopic dermatitis (AD), one on seasonal allergic rhinitis [SAR], and one on FA] consisting of 2,376 participants met the inclusion criteria. For severe asthma, omalizumab may reduce exacerbations at 12 weeks [risk ratio (RR), 0.52; 95% confidence interval (CI), 0.31-0.89], 24 weeks (RR, 0.69; 95% CI, 0.55-0.85; GRADE: moderate-quality evidence), and 52 weeks (RR, 0.62; 95% CI, 0.40-0.94; GRADE: moderate-quality evidence) and reduce the dose of inhalation corticosteroid compared with placebo. For severe AD, the association between omalizumab and allergic symptom improvement [i.e., SCORing Atopic Dermatitis or Paediatric Allergic Disease Quality of Life Questionnaire (PADQLQ)] was not confirmed. For severe SAR, omalizumab showed greater improvement in symptom load scores and saved rescue medication days. For FA, omalizumab demonstrated superiority in desensitisation compared with placebo. To date, no clinically significant drug-related SAEs have been reported.

CONCLUSION

For severe or uncontrolled asthma, AD, SAR, and FA, omalizumab may be associated with improved allergic symptoms and safety in children. Future studies should focus on the benefits and pharmacoeconomic evaluation of omalizumab in multiple allergic diseases compared with other treatments.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/PROSPERO], identifier [CRD42021271863].