Predictive biomarkers for response to omalizumab in patients with severe allergic asthma: a meta-analysis

Endotyping Chronic Respiratory Diseases: T2 Inflammation in the United Airways Model

Over the past 15 years, the paradigm of viewing the upper and lower airways as a unified system has progressively shifted the approach to chronic respiratory diseases (CRDs). As the global prevalence of CRDs continues to increase, it becomes evident that acknowledging the presence of airway pathology as an integrated entity could profoundly impact healthcare resource allocation and guide the implementation of pharmacological and rehabilitation strategies. In the era of precision medicine, endotyping has emerged as another novel approach to CRDs, whereby pathologies are categorized into distinct subtypes based on specific molecular mechanisms. This has contributed to the growing acknowledgment of a group of conditions that, in both the upper and lower airways, share a common type 2 (T2) inflammatory signature. These diverse pathologies, ranging from allergic rhinitis to severe asthma, frequently coexist and share diagnostic and prognostic biomarkers, as well as therapeutic strategies targeting common molecular pathways. Thus, T2 inflammation may serve as a unifying endotypic trait for the upper and lower airways, reinforcing the practical significance of the united airways model. This review aims to summarize the literature on the role of T2 inflammation in major CRDs, emphasizing the value of common biomarkers and integrated treatment strategies targeting shared molecular mechanisms.

Elevated baseline soluble FcεRI may be linked to early response to omalizumab treatment in chronic spontaneous urticaria

BACKGROUND

Omalizumab, an anti-IgE monoclonal antibody, is an effective treatment in chronic spontaneous urticaria (CSU). Predictors of fast and good response for omalizumab treatment have not yet been identified and characterized.

OBJECTIVE

To evaluate whether soluble FcεRI (sFcεRI), a marker of IgE-mediated mast cell activation, predicts the time of response to omalizumab in CSU.

METHODS

Sera of 67 CSU patients were obtained before omalizumab treatment and analysed for sFcεRI levels by ELISA (2 ng/mL was used as cut-off for elevated sFcɛRI). Treatment response during the first 4 weeks was assessed with the urticaria activity score (UAS7), urticaria control test (UCT) and the rolling UAS7 (rUAS7).

RESULTS

Elevated pre-treatment sFcɛRI levels were detected in more than 70% of patients with completely controlled disease (UCT = 16) and well-controlled disease (UCT = 12-15) and were significantly associated with disease control (χ2  = 4.94, p < 0.05). More than half of the patients (14/25) with low levels had poor disease control (UCT < 12). Of the patients who achieved complete and marked UAS7 response, respectively, 75% and 63% had elevated baseline sFcɛRI levels. Post-treatment UAS7 scores were lower in patients with elevated sFcɛRI levels reaching statistical significance at Week 3 (p < 0.05). Patients with elevated baseline sFcɛRI levels achieved rUAS7 ≤ 6 and = 0 earlier than those with lower levels (Days 9 vs. 13 and Days 12 vs. 14, respectively).

CONCLUSION

Elevated sFcεRI serum levels predict early and good response to treatment with omalizumab, which may help to better design treatment options for CSU patients.

The Significance of Eosinophil-to-Lymphocyte Ratio in Predicting Response to Omalizumab Treatment in Patients with Bullous Pemphigoid: A Case Series

Omalizumab, a monoclonal anti-IgE antibody, has been used off-label in a few case series of bullous pemphigoids (BPs) with rapid efficacy and high safety profile. However, there is a lack of data to select patients who would get the most therapeutic benefit from omalizumab therapy. To assess if eosinophil-to-lymphocyte ratio (ELR), total serum IgE level, and serum eosinophil percentage would be useful in predicting response to omalizumab therapy in patients with BP. Medical records of 10 patients with BP treated with omalizumab were retrospectively analysed for clinical and laboratory data. ELRs, total serum IgE levels, and serum eosinophil percentages were compared between groups of complete responders and partial responders/flare-ups, but the results were not statistically significant. Studies with larger sample sizes should be done to predict the role of type 2 immunity markers in omalizumab therapy of BP patients.

Real-world effectiveness and predictors of super-responders to dupilumab in a Chinese uncontrolled asthma cohort

Background: Dupilumab has been shown to be effective in clinical trials for moderate-to-severe uncontrolled asthma. However, the efficacy of dupilumab in the real world and the prediction of treatment response have not been well studied in patients with asthma. Objective: To investigate the efficacy of dupilumab and explore predictors of super-responders in a Chinese retrospective cohort. Methods: From January 2021 through December 2022, the patients with uncontrolled asthma who were treated with dupilumab for 4 months were included. Symptom control, type 2 inflammatory biomarkers, and lung function were collected at baseline and follow-up for efficacy assessment. Super-responders were defined as exacerbation-free, off maintenance of oral corticosteroids (mOCS), and with a score of the five-item Asthma Control Questionnaire (ACQ-5) of <0.5. The uni- and multivariable logistic regressions were used to construct predictive models for super-responders based on baseline features. Results: A total of 53 patients were included. After 4 months treatment, the median (interquartile range [IQR]) ACQ-5 score decreased from 1.8 (1.6-2.4) to 0.4 (0.2-0.8) (p < 0.001), the median (IQR) number of exacerbations, from 0.0 (0.0-1.0) to 0.0 (0.0-0.0) (p = 0.005). The median (IQR) dose of mOCS (prednisone equivalent) decreased from 15.0 mg/day (8.8-22.5 mg/day) to 2.5 mg/day (0.0-10.0 mg/day) (p = 0.008) in nine patients who were receiving mOCS. All efficacy assessment parameters, including sputum eosinophil were significantly improved, while blood eosinophil count did not decline (530 cells/mm³ [300-815 cells/mm³] versus 560 cells/mm³ [220-938 cells/mm³], p = 0.710). After taking dupilumab, 25 of 53 patients (47.2%) achieved a super-response. The age of onset < 42 years (odds ratio [OR] 7.471 [95% confidence interval {CI}, 1.286-43.394) and the baseline fractional exhaled nitric oxide (FeNO) of 25-50 ppb (OR 35.038 [95% CI, 3.104-395.553]) predicted super-responders, which showed a C-index of 0.822 (95% CI, 0.697-0.947). Conclusion: Dupilumab significantly improved symptom control, type 2 inflammatory markers, and lung function in Chinese patients with uncontrolled asthma. Airway eosinophils, rather than blood eosinophils, can be a reliable indicator of therapeutic efficacy. The early-onset asthma as well as the medium-high level of baseline FeNO contributed to the prediction of super-responders.

Developments in the Management of Severe Asthma in Children and Adolescents: Focus on Dupilumab and Tezepelumab

Severe asthma in children and adolescents exerts a substantial health, financial, and societal burden. Severe asthma is a heterogeneous condition with multiple clinical phenotypes and underlying inflammatory patterns that might be different in individual patients. Various add-on treatments have been developed to treat severe asthma, including monoclonal antibodies (biologics) targeting inflammatory mediators. Biologics that are currently approved to treat children (≥ 6 years of age) or adolescents (≥ 12 years of age) with severe asthma include: anti-immunoglobulin E (omalizumab), anti-interleukin (IL)-5 (mepolizumab), anti-IL5 receptor (benralizumab), anti-IL4/IL13 receptor (dupilumab), and antithymic stromal lymphopoietin (TSLP) (tezepelumab). However, access to these targeted treatments varies across countries and relies on few and crude indicators. There is a need for better treatment stratification to guide which children might benefit from these treatments. In this narrative review we will assess the most recent developments in the treatment of severe pediatric asthma, as well as potential biomarkers to assess treatment efficacy for this patient population.

Effects of omalizumab combined with budesonide formoterol on clinical efficacy, pulmonary function, immune function, and adverse reactions in children with moderate and severe allergic asthma

OBJECTIVE

To evaluate the clinical efficacy and safety of combining omalizumab with budesonide formoterol to treat children with moderate and severe allergic asthma, and investigate the effect of this combination therapy on pulmonary and immune functions.

METHODS

The data of 88 children with moderate and severe allergic asthma, who were admitted to our hospital between July 2021 and July 2022, were included in the study. The patients were randomly assigned either to control group (n = 44; received budesonide formoterol inhalation therapy) or experimental group (n = 44; received omalizumab subcutaneous injection + budesonide formoterol inhalation therapy) using computer-generated randomization. The clinical efficacy, asthma control (measured using childhood Asthma-Control Test [C-ACT] score), pulmonary function (forced expiratory volume in 1 s, forced vital capacity, and peak expiratory flow), immune function (cluster of differentiation 3 cells [CD3⁺ cells], cluster of differentiation 4 cells [CD4⁺ cells], immunoglobulin G, immunoglobulin A, and immunoglobulin E), and adverse reactions were observed and compared between both groups.

RESULTS

After treatment, the experimental group had improved levels of pulmonary function and immune function indexes, higher C-ACT scores, and a higher overall response rate than the control group (P < 0.05). In addition, the incidence of adverse reactions was not significantly different between both groups (P > 0.05).

CONCLUSION

The combination of omalizumab with budesonide formoterol for treating moderate and severe allergic asthma in children demonstrated promising clinical efficacy and improved their pulmonary and immune functions, leading to more rational asthma control. The combined regimen demonstrated satisfactory clinical safety and deserved clinical promotion.

Evaluation of the clinical features and laboratory data of patients with severe asthma classified as super-responder or non super-responder to omalizumab treatment: a single-centre real-life study

INTRODUCTION

Omalizumab is used for the treatment of severe allergic asthma.

OBJECTIVE

The aim of this study was to evaluate the clinical features and laboratory data of patients with severe allergic asthma classified as super-responder or non super-responder to omalizumab.

METHODS

Comparisons were made of the laboratory data and clinical features of patients with severe allergic asthma. Patients who had no asthma exacerbation, no oral corticosteroid (OCS) use, asthma control test (ACT) score >20 and forced expiratory volume in 1 s (FEV1) >80% were considered super-responder after omalizumab.

RESULTS

A total of 90 patients were included in the study, comprising 19 (21.1%) males. The age at onset of asthma, allergic rhinitis rate, number of endoscopic sinus surgeries (ESS), intranasal corticosteroid (INS) use, baseline FEV 1 (%) and ACT score were significantly higher in the omalizumab super-responder group (p = 0.013, p = 0.015, p = 0.002, p = 0.001, p = 0.001 and p < 0.001, respectively). The duration of asthma, rate of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP), regular use of OCS, baseline eosinophil count and eosinophil-to-lymphocyte ratio were significantly higher in the omalizumab non super-responder group (p = 0.015, p < 0.001, p = 0.004, p < 0.001 and p < 0.001, respectively). Blood eosinophil count (AUC: 0.187, p < 0.001), eosinophil-to-lymphocyte ratio (AUC: 0.150, p < 0.001) and FEV1 (%) (AUC:0.779, p = 0.001) were determined to have diagnostic value in predicting the treatment response to omalizumab of patients with severe allergic asthma.

CONCLUSION

High-blood eosinophil levels, CRSwNP and low pretreatment lung capacity may affect omalizumab treatment response in patients with severe allergic asthma. These results should be supported by further multicenter real-life studies.

Exploring the Interaction between Fractional Exhaled Nitric Oxide and Biologic Treatment in Severe Asthma: A Systematic Review

BACKGROUND

Fractional exhaled nitric oxide (FeNO) is a biomarker of airway inflammation associated with airway hyper-responsiveness and type-2 inflammation. Its role in the management of severe asthmatic patients undergoing biologic treatment, as well as FeNO dynamics during biologic treatment, is largely unexplored.

PURPOSE

The aim was to evaluate published data contributing to the following areas: (1) FeNO as a predictive biomarker of response to biologic treatment; (2) the influence of biologic treatment in FeNO values; (3) FeNO as a biomarker for the prediction of exacerbations in patients treated with biologics.

METHODS

The systematic search was conducted on the Medline database through the Pubmed search engine, including all studies from 2009 to the present.

RESULTS

Higher baseline values of FeNO are associated with better clinical control in patients treated with omalizumab, dupilumab, and tezepelumab. FeNO dynamics during biologic treatment highlights a clear reduction in FeNO values in patients treated with anti-IL4/13 and anti-IL13, as well as in patients treated with tezepelumab. During the treatment, FeNO may help to predict clinical worsening and to differentiate eosinophilic from non-eosinophilic exacerbations.

CONCLUSIONS

Higher baseline FeNO levels appear to be associated with a greater benefit in terms of clinical control and reduction of exacerbation rate, while FeNO dynamics during biologic treatment remains a largely unexplored issue since few studies have investigated it as a primary outcome. FeNO remains detectable during biologic treatment, but its potential utility as a biomarker of clinical control is still unclear and represents an interesting research area to be developed.