Omalizumab response in patients with asthma by number and type of allergen

[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.

FoxO4 mediates macrophage M2 polarization by promoting LXA4R expression in an ovalbumin-induced allergic asthma model in mice

BACKGROUND

Asthma imposes a heavy burden due to its high prevalence. Forkhead box O4 (FoxO4) proteins participate in the modulation of cell progression. However, the role and mechanism of FoxO4 in asthma remains uncharted.

METHODS

An allergic asthma model was constructed by the induction of ovalbumin and interleukin (IL)-4 in mice and monocyte/macrophage-like Raw264.7 cells, respectively. The role and mechanism of FoxO4 in asthma was determined by pathological staining, immunofluorescence assay, measurement of inflammatory cells in the blood, reverse transcription quantitative polymerase chain reaction (RT-qPCR), Western blot analysis, and flow cytometry.

RESULTS

Ovalbumin treatment triggered an obvious inflammatory cell infiltration with a prominent increase in F4/80⁺ cell numbers. The relative messenger RNA (mRNA) and protein expressions of FoxO4 were increased in both ovalbumin-induced mice and interleukin-4 (IL-4)-induced Raw264.7 cells. Inhibition of FoxO4 via AS1842856 reduced inflammatory cell infiltration, the number of Periodic Acid Schiff+ (PAS+) goblet cells, the numbers of inflammatory cells in the blood, and the airway resistance in ovalbumin-induced mice. Besides, interference of FoxO4 decreased the number of F4/80⁺CD206⁺ cells, and the relative protein expressions of CD163 and Arg1 in vivo and in vitro. Mechanically, suppression of FoxO4 diminished the relative mRNA and protein expressions of LXA4R in both ovalbumin-induced mice and IL-4-induced Raw264.7 cells. Overexpression of LXA4R reversed the outcomes caused by repression of FoxO4, including airway resistance, the number of F4/80+ cells, the proportion of CD206+ cells in ovalbumin-induced mice, and the proportion of F4/80⁺CD206⁺ cells in IL-4-induced Raw264.7 cells.

CONCLUSION

FoxO4/LXA4R axis mediated macrophage M2 polarization in allergic asthma.

The effect of applied force and device design on skin prick test performance

BACKGROUND

Skin prick tests (SPTs) are difficult to standardize, and SPT performance mainly relies on the clinician's expertise. So far, the effect of various factors such as device types, shape, variety of material type, and applied force on the performance of SPT has not been extensively investigated.

OBJECTIVE

To investigate the effect of various factors, including type or shape of devices, material type, and applied force, on the performance of SPT.

METHODS

Four SPT devices with different shapes and materials were applied on 12 subjects under 3 different applied forces (30, 45, and 60 g). The results were compared with standard method using an ALK lancet pricked by an experienced clinician.

RESULTS

A total of 480 pricks were conducted on 12 subjects. The wheal sizes and sensitivities of all devices increased with higher applied forces. The thinner lancets with a long sharp tip had relatively higher analytical sensitivities and provided 100% sensitivity at applied forces of 45 g and above. The pain scores of all devices at applied forces of 30 to 60 g ranged from 1.00 to 1.81 with minimal incidences of bleeding (0%-4.17%), whereas the pain score of the standard method by the ALK lancet was 2.08 with much higher incidences of bleeding at 27.08%.

CONCLUSION

The type/shape of the SPT device and applied force are the essential factors affecting the performance of SPT. The study result could pave the way toward higher performance and standardized SPT.

TRIAL REGISTRATION

The Thai Clinical Trials Registry identification number: TCTR20220627004 (https://www.thaiclinicaltrials.org/show/TCTR20220627004).

Specific IgE Response and Omalizumab Responsiveness in Severe Allergic Asthma

Objective

Omalizumab has demonstrated clinical efficacy in patients with severe allergic asthma sensitized to perennial allergens and/or severe pollinosis through inhibition of IgE-dependent allergic response. When considering the "one airway, one disease" concept, sensitization to pollen could predict responsiveness to omalizumab. This study aimed to assess whether the pretreatment specific IgE response could be a predictor of responsiveness to omalizumab in severe allergic asthma sensitized to perennial allergens.

Methods

In this retrospective study, 41 adult patients with severe allergic asthma sensitized to perennial allergens (27 females; mean age 59 years) who had completed 52-week omalizumab treatment were enrolled. The Global Evaluation of Treatment Effectiveness was performed, and demographic characteristics and the positive ratios of specific IgE responses classified into five subgroups (pollen, dust mite, house dust, mold, and animal dander) were compared between responders and non-responders. Multivariate logistic regression analyses were performed to identify predictors of responsiveness to omalizumab.

Results

Thirty-one patients (76%) were identified as responders. The number of sensitized aeroallergen subgroups and sensitization to pollens were significantly higher in responders than in non-responders (both p<0.05). Multivariate logistic regression analysis showed that sensitization to pollen (OR = 8.41, p = 0.02) was independently associated with the effectiveness of omalizumab.

Conclusion

Pretreatment serum pollen-specific IgE could be a predictor of responsiveness to omalizumab.

Dupilumab Efficacy in Patients with Uncontrolled Moderate-to-Severe Type 2 Asthma Regardless of Perennial Aeroallergen Sensitization

Purpose

Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukins-4/-13, key and central drivers of type 2 (T2) inflammation in multiple diseases. In phase 3 QUEST (NCT02414854), dupilumab vs placebo significantly reduced asthma exacerbation rates (AER) and improved pre-bronchodilator forced expiratory volume in 1 second (FEV₁) in patients with uncontrolled, moderate-to-severe asthma, with greater effects in patients with elevated T2 biomarkers (≥150 eosinophils/µL or fractional exhaled nitric oxide [FeNO] ≥25 parts per billion). Overall safety was consistent with the known dupilumab safety profile. This post hoc analysis assessed dupilumab efficacy in QUEST patients with T2 asthma with evidence of an allergic phenotype (baseline serum IgE ≥30 IU/mL and aeroallergen-specific IgE ≥0.35 IU/mL) by number of aeroallergen sensitizations: 1, 2, 3, or ≥4. Non-sensitized patients (serum total IgE <30 IU/mL without evidence of allergic phenotype) were also assessed.

Patients and Methods

Endpoints were annualized AER, change from baseline in pre-bronchodilator FEV₁ and asthma control (5-item Asthma Control Questionnaire [ACQ-5]), and FeNO and serum total IgE levels over the 52-week treatment period.

Results

In all subgroups by number of allergens sensitized, dupilumab vs placebo reduced AER by 35-67% and improved both pre-bronchodilator FEV₁ at Week 12 (least squares mean differences: 0.10-0.26 L across subgroups) and ACQ-5 score at Week 52 (-0.26 to -0.43). Dupilumab significantly reduced FeNO and total IgE levels at Week 52 compared with placebo. Similar results were observed in non-sensitized patients.

Conclusion

Dupilumab improved clinical outcomes and reduced biomarker levels in patients with uncontrolled, moderate-to-severe T2 asthma irrespective of allergen sensitization status or number.

Clinical Trial Registration

ClinicalTrials.gov Identifier: NCT02414854.

Prevention of omalizumab for seasonal allergic rhinoconjunctivitis: a retrospective cohort study

Background

Allergic rhinoconjunctivitis (ARC) is an allergic disease that is characterized by conjunctival and nasal symptoms such as edema and congestion of conjunctiva, rhinorrhea, sneezing, and blocked nose. Seasonal ARC (SARC) is usually induced by seasonal allergens and often occurs at specific times during the year. Traditional treatments of SARC include nasal corticosteroids, antihistamines, and mast cell membrane stabilizers. Biological agents such as omalizumab have also been proved effective in the treatment of SARC.

Objectives

We aim to certify the preventative efficacy of omalizumab for SARC and explore its influence factors.

Methods

Medical records of 64 SARC patients were retrospectively analyzed, and generalized linear models were used to analyze influence factors of efficacy of omalizumab.

Results

Compared with forepassed pollen season without omalizumab treatment, the combined symptom and medication score (CSMS) of ARC with pre-seasonal omalizumab was significantly lower (with omalizumab: 0.67[0.00,1.83], without omalizumab: 4.00[2.83,4.96], p<0.001, max score=6). Subgroup analysis was conducted to explore the influence factor of preventative efficacy of omalizumab. The CSMS with omalizumab treatment were not significantly different among different age, gender, dosage, number of injections, and injection date subgroups (p>0.05).

Conclusion

Pre-seasonal omalizumab treatment could significantly relieve SARC related symptoms and reduce medication use. This preventative efficacy would not be influenced by the dosage and number of injections of omalizumab. A single dose of 150mg omalizumab could achieve a satisfactory outcome.

Viral Infection and Respiratory Exacerbation in Children: Results from a Local German Pediatric Exacerbation Cohort

Respiratory viruses play an important role in asthma exacerbation, and early exposure can be involved in recurrent bronchitis and the development of asthma. The exact mechanism is not fully clarified, and pathogen-to-host interaction studies are warranted to identify biomarkers of exacerbation in the early phase. Only a limited number of international exacerbation cohorts were studied. Here, we have established a local pediatric exacerbation study in Germany consisting of children with asthma or chronic, recurrent bronchitis and analyzed the viriome within the nasopharyngeal swab specimens derived from the entire cohort (n = 141). Interestingly, 41% of exacerbated children had a positive test result for human rhinovirus (HRV)/human enterovirus (HEV), and 14% were positive for respiratory syncytial virus (RSV). HRV was particularly prevalent in asthmatics (56%), wheezers (50%), and atopic (66%) patients. Lymphocytes were decreased in asthmatics and in HRV-infected subjects, and patients allergic to house dust mites were more susceptible to HRV infection. Our study thus confirms HRV infection as a strong 'biomarker' of exacerbated asthma. Further longitudinal studies will show the clinical progress of those children with a history of an RSV or HRV infection. Vaccination strategies and novel treatment guidelines against HRV are urgently needed to protect those high-risk children from a serious course of disease.

Use of biologics for the treatment of moderate-to-severe asthma: the age of personalized medicine

PURPOSE OF REVIEW

There are multiple FDA-approved biologics to treat poorly controlled moderate-to-severe asthma. Given the heterogeneity of asthma and the lack of head-to-head data between biologics, selecting the best biologic for a patient can be difficult. This review summarizes the key literature to date, in hopes of facilitating an evidence-based approach to selecting the most appropriate biologic for patients with asthma.

RECENT FINDINGS

In addition to unique mechanisms of action, there is increasing literature on predictors of response to each biologic, such as sensitizations to aeroallergens, peripheral eosinophil count, total serum IgE, and exhaled nitric oxide. Biologics available for asthma are also being increasingly studied in comorbid conditions with asthma, and this may facilitate selecting the most appropriate biologic for a patient. In the absence of head-to-head studies, there is literature of switching between biologics whenever necessary.

SUMMARY

The authors outline an approach to selecting a biologic based on various considerations, and hope this suggested approach facilitates selecting the biologic most suitable for each individual with poorly controlled moderate-to-severe asthma.

Evolving Concept of Severe Asthma: Transition From Diagnosis to Treatable Traits

In recent decades, the concept of severe asthma has evolved from an umbrella term encompassing patients with high-intensity treatment needs to a clinical syndrome with heterogeneous, albeit distinct, pathophysiological processes. Biased and unbiased cluster approaches have been used to identify several clinical phenotypes. In parallel, cellular and molecular approaches allow for the development of biological therapies, especially targeting type 2 (T2) cytokine pathways. Although T2-biologics have significantly improved clinical outcomes for patients with severe asthma in real-world practice, questions on the proper use of biologics remain open. Furthermore, a subset of severe asthma patients remains poorly controlled. The unmet needs require a new approach. The “treatable traits” concept has been suggested to address a diversity of pathophysiological factors in severe asthma and overcome the limitations of existing treatment strategies. With a tailored therapy that targets the treatable traits in individual patients, better personalized medical care and outcomes should be achieved.

Interleukin-22 attenuates allergic airway inflammation in ovalbumin-induced asthma mouse model

BACKGROUND

Allergic asthma is a chronic airway inflammatory disease with a number of cytokines participating in its pathogenesis and progress. Interleukin (IL)-22, which is derived from lymphocytes, acts on epithelial cells and play a role in the chronic airway inflammation. However, the actual role of IL-22 in allergic asthma is still unclear. Therefore, we explored the effect of IL-22 on allergic airway inflammation and airway hyperresponsiveness (AHR) in an ovalbumin (OVA)-induced asthma mouse model.

METHODS

To evaluate the effect of IL-22 in an allergic asthma model, BALB/c mice were sensitized and challenged with OVA; then the recombinant mouse IL-22 was administered intranasally 24 h prior to each challenge. The IL-22 levels in lung homogenates and bronchoalveolar lavage fluid (BALF) were measured by enzyme linked immunosorbent assay, respectively. AHR was evaluated through indicators including airways resistance (Rrs), elastance (Ers) and compliance (Crs); the inflammatory cell infiltration was assessed by quantification of differential cells counts in BALF and lung tissues stained by hematoxylin and eosin (H&E); IL-22 specific receptors were determined by immunohistochemistry staining.

RESULTS

The concentration of IL-22 was significantly elevated in the OVA-induced mice compared with the control mice in lung homogenates and BALF. In the OVA-induced mouse model, IL-22 administration could significantly attenuate AHR, including Rrs, Ers and Crs, decrease the proportion of eosinophils in BALF and reduce inflammatory cell infiltration around bronchi and their concomitant vessels, compared with the OVA-induced group. In addition, the expression of IL-22RA1 and IL-10RB in the lung tissues of OVA-induced mice was significantly increased compared with the control mice, while it was dramatically decreased after the treatment with IL-22, but not completely attenuated in the IL-22-treated mice when compared with the control mice.

CONCLUSION

Interleukin-22 could play a protective role in an OVA-induced asthma model, by suppressing the inflammatory cell infiltration around bronchi and their concomitant vessels and airway hyperresponsiveness, which might associate with the expression of its heterodimer receptors. Thus, IL-22 administration might be an effective strategy to attenuate allergic airway inflammation.

Effective Management of Severe Asthma with Biologic Medications in Adult Patients: A Literature Review and International Expert Opinion

Severe asthma often remains uncontrolled despite effective treatments and evidence-based guidelines. A group of global experts in asthma and biologic medications from 9 countries considered the most relevant clinical variables to manage severe asthma in adult patients and guide treatment choice. The resulting recommendations address the investigation of biomarker levels (blood eosinophil count along with fractional concentration of exhaled nitric oxide [FeNO]), clinical features (oral corticosteroid [OCS] dependence, specific comorbid disease entities associated with severe type 2 asthma), and safety considerations. Current evidence suggests that biomarkers, including both blood or sputum eosinophil counts as well as FeNO, add prognostic and predictive value and should be measured in all patients with severe asthma. OCS use is an important factor in biologic selection, especially given the documented ability of some biologics to reduce OCS dependence. Comorbid diseases and relevant safety considerations to each biologic should also be considered. More data are needed to determine whether biomarker profiles identify patients suited to one biologic versus another as limited data support differential predictors of response. Further prospective head-to-head trials and post hoc analyses of clinical trial data are warranted. The authors believe that these recommendations have value as they offer expert opinion to assist health care providers in making difficult decisions regarding the quality of care in severe, type 2 asthma with biologic medications. They remain conditional and are based on limited data owing to a lack of head-to-head comparisons.