Prediction of clinical response to omalizumab in moderate-to-severe asthma patients using the change in total serum IgE level

Retrospective analysis of laboratory results in 18 cases of severe asthma treated with omalizumab

OBJECTIVE

The aim of this study was to explore the laboratory results in severe as asthma patients with omalizumab therapy and provide evidence for estimating omalizumab efficacy.

METHODS

Retrospective study of 18 patients with severe asthma received omalizumab therapy in Shanghai General Hospital from 2020 to 2022 was performed. The basic data of patients were collected. The absolute number and the percentage of basophil and eosinophil in peripheral blood, total IgE level in serum, and as pulmonary function were detected at the beginning of treatment and 4 months after treatment. Differences between two groups were analyzed using Paired T test.

RESULTS

The most common allergens collected from patients with moderate to severe asthma were dust mite (positive ratio 55.56%), mixed mold (16.67%), cat and dog dander, and Aspergillus fumigatus (11.11%). There was no significant difference in eosinophil and basophil counts in peripheral blood between the two groups. However, serum total IgE levels increased from (437.55±279.35) KU/L to (1071.42±721.28) KU/L (P=0.004), and FEV1/FVC ratio increased from (65.53±14.15)% to (73.91±13.63)% (P=0.005) after 4 months of treatment.

CONCLUSIONS

The existing laboratory indicators for evaluation of omalizumab efficacy are still very limited, and new biomarkers need to be further developed. Elevated serum IgE levels at four weeks of treatment and FEV1/FVC may be potential indicators for omalizumab monitoring.

The ratio of total IgE level at week 16 to baseline significantly correlated with the clinical response to omalizumab in moderate to severe allergic rhinitis patients

OBJECTIVE

To analyze whether the ratio of total IgE level at week 16 to baseline could be used as an indicator to evaluate clinical efficacy of patients treated with omalizumab.

METHODS

We retrospectively analyzed the clinical characteristics of 62 patients with moderate-to-severe allergic rhinitis treated with omalizumab, and compared the pre-and post-treatment nasal visual analog scale (n-VAS) scores, the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), Rhinitis Control Assessment Test (RCAT), improvement in nasal congestion, number of acute episodes of rhinitis, and total IgE levels in serum. The relationship between the efficacy of treatment with omalizumab and the change in total IgE levels before and after treatment was further analyzed.

RESULTS

This study included 62 patients with moderate-to-severe allergic rhinitis, of which 48 demonstrated significant improvement after 16 weeks of omalizumab therapy; the results of 16 weeks' omalizumab treatment in 14 patients did not show significant improvements in allergic rhinitis symptoms based on RACT scores. After 16 weeks of omalizumab treatment, the RQLQ score decreased from (36.6 ± 13.7) at baseline level to (9.1 ± 12.6) after 16 weeks treatment.The ratio of total IgE at week 16 to total IgE levels at baseline was (2.9 ± 1.4) KU/L in 62 patients. And the ratio of total IgE levels at week 16 to total IgE levels at baseline was (3.3 ± 1.4) KU/L for responders and (1.6 ± 0.5) KU/L for non-responders.

CONCLUSION

The ratio of total IgE level at week 16 to baseline significantly correlated with the clinical response to omalizumab in moderate to severe allergic rhinitis patients, when the ratio of total IgE level at week 16 to baseline was ≥2.0. Omalizumab effectively treated patients with moderate-to-severe allergic rhinitis, and improved their quality of life.

Role of clinical biomarkers in predicting the effectiveness of omalizumab

OBJECTIVE

To explore whether baseline clinical biomarkers and characteristics can be used to predict the responsiveness of omalizumab.

METHODS

We retrospectively analyzed a cohort of patients with severe asthma who received omalizumab treatment and collected their baseline data and relevant laboratory examination results along with case records of omalizumab treatment responsiveness after 16 weeks. We compared the differences in variables between the group of patients that responded to omalizumab therapy and the non-responder group, and then performed univariate and multivariate logistic regression. Finally, we analyzed the difference in response rate for subgroups by selecting cut-off values for the variables using Fisher's exact probability method.

RESULTS

This retrospective, single-center observational study enrolled 32 patients with severe asthma who were prescribed daily high-dose inhaled corticosteroids and long-acting β2 receptor agonists on long-acting muscarinic receptor antagonists with or without OCS. Data on age, sex, BMI, bronchial thermoplasty, FeNO, serum total IgE, FEV1, blood eosinophils, induced sputum eosinophils, blood basophils, and complications were not significantly different between the responder and non-responder groups. In the univariate and multivariate logistic regression, all the variants were not significant, and we were unable to build a regression model. We used normal high values and the mean or median of variables as cut-off values to create patient subgroups for the variables and found no significant difference in the omalizumab response rate between the subgroups.

CONCLUSION

The responsiveness of omalizumab is not associated with pretreatment clinical biomarkers, and these biomarkers should not be used to predict the responsiveness of omalizumab.

Response to Omalizumab as an Add-On Therapy in the Treatment of Allergic Asthma in Adult Chinese Patients-A Retrospective Study

(a) Background: Omalizumab is an anti-IgE humanized monoclonal antibody marketed in China for the conventional treatment of poorly controlled moderate-to-severe allergic asthma. Numerous clinical trials have demonstrated the effectiveness of omalizumab, but the data from studies in actual clinical treatment are still relatively limited. (b) Methods: Thirty-two patients with moderate-to-severe allergic asthma treated with omalizumab on the basis of ICS-LABA (inhaled corticosteroids/long-acting beta2-agonist) were selected. Clinical characteristics before and after treatment were collected to analyze the relationship between changes in serum total IgE levels and peripheral blood EOS (eosinophil) levels, FEV1 (forced expiratory volume in 1 second), PEF (peak expiratory flow), OCS (oral glucocorticoid) dosage, ATC (asthma control test) score, and the number of acute exacerbations and the treatment response, in order to observe the efficacy of omalizumab in addition to primary therapy, and to investigate whether baseline clinical characteristics such as serum total IgE and EOS levels could predict a treatment response. (c) Results: Using the ACT score as an evaluation, 68.75% of patients benefited from omalizumab treatment at the end of 16 weeks. The response group has a reduction in OCS dosage (p-values of 0.026 and 0.039), a significant reduction in ACT scores (both p < 0.001), and a reduction in the number of acute exacerbations (p = 0.034 and 0.025, respectively) after omalizumab treatment. The binary logistics analysis of factors affecting the effectiveness of omalizumab in the treatment of allergic asthma were total serum IgE and the presence of comorbidities (p-values of 0.039 and 0.046, respectively). (d) Conclusions: Combining omalizumab with ICS-LABA for 16 weeks significantly improves asthma symptoms in Chinese adults and can be used as an add-on treatment. In addition, high serum IgE levels and the presence of comorbidities were predictors of its therapeutic efficacy.

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

BACKGROUND

Predicting omalizumab treatment response has been a challenge and significant aspect for selecting suitable severe allergic asthma patients for omalizumab use.

OBJECTIVE

To determine which domains of pretreatment baseline characteristics predict omalizumab treatment response among asthmatic patients.

METHODS

Electronic bases were searched for eligible studies that reported potential biomarkers that could predict omalizumab responsiveness and efficacy. Patients who accepted omalizumab treatment were stratified into responders and non-responders. WMD, OR, and their 95%CI were used to access the differences between those omalizumab receivers. Sensitivity analysis and subgroup analysis were conducted for potential heterogeneity.

RESULTS

A total of 41 studies evaluating efficacy predictors of omalizumab were included in this meta-analysis. The pooled results showed that omalizumab responders had significantly younger age in the adult subgroup, higher pretreatment total serum IgE level, percent predicted FEV₁ and FeNO than that non-responder. We further confirmed that higher blood eosinophil counts and total serum IgE levels are useful markers for selecting asthma patients who may benefit more from omalizumab.

CONCLUSIONS

Pre-treatment blood eosinophil counts and total serum IgE level can be a useful efficacy predictor in selecting allergic asthma patients for omalizumab treatment.

Advances and Challenges of Antibody Therapeutics for Severe Bronchial Asthma

Asthma is a disease that consists of three main components: airway inflammation, airway hyperresponsiveness, and airway remodeling. Persistent airway inflammation leads to the destruction and degeneration of normal airway tissues, resulting in thickening of the airway wall, decreased reversibility, and increased airway hyperresponsiveness. The progression of irreversible airway narrowing and the associated increase in airway hyperresponsiveness are major factors in severe asthma. This has led to the identification of effective pharmacological targets and the recognition of several biomarkers that enable a more personalized approach to asthma. However, the efficacies of current antibody therapeutics and biomarkers are still unsatisfactory in clinical practice. The establishment of an ideal phenotype classification that will predict the response of antibody treatment is urgently needed. Here, we review recent advancements in antibody therapeutics and novel findings related to the disease process for severe asthma.

Omalizumab-induced aspirin tolerance in N-ERD patients is independent of atopic sensitization

BACKGROUND

NSAID-exacerbated respiratory disease (N-ERD) comprises the triad of chronic rhinosinusitis with nasal polyps (CRSwNP), asthma and intolerance to inhibitors of the cyclooxygenase-1-enzyme. The impact of omalizumab on prevention of aspirin-induced hypersensitivity in N-ERD patients with and without atopic sensitization has not been thoroughly addressed.

OBJECTIVE

To investigate the effect of omalizumab treatment on aspirin tolerance in atopic and non-atopic N-ERD patients.

METHODS

This single-center, prospective trial evaluated overall omalizumab-induced aspirin tolerability in N-ERD patients by performing aspirin challenge testing before and after 6 months of anti-IgE therapy. The impact of omalizumab on CRSwNP, asthma as well as serum and tissue biomarkers in patients with and without comorbid atopic sensitizations was further analyzed.

RESULTS

Out of 33 patients included in the study, 56% developed complete aspirin tolerance and 18% tolerated higher dosages after 24 weeks. Polyp size and disease-specific symptoms (NPS:-1.9±0.3,p<0.001;SNOT-20:-16.7±3.7,p<0.001;ACT:+3.2±0.7,p<0.001) improved in all patients irrespective of atopic sensitization. Effectiveness of omalizumab was accompanied by an increase in mean total serum IgE (307.8±42kU/L,p<0.001) and a decrease in ECP (-10.6±6.7 μg/L ) and in relative eosinophilia (-2.5±0.7%, p<0.01). While there was a significant reduction of tissue IgE (p<0.05) in all patients after 4 weeks, the number of local eosinophils decreased only in atopic individuals (p<0.05).

CONCLUSION

Omalizumab induced complete aspirin tolerance in the majority (56%) of patients independent of atopic sensitization and demonstrated clinical efficacy in the treatment of CRSwNP and asthma. Inhibition of IgE can therefore be a promising treatment option in preventing NSAID hypersensitivity reactions in N-ERD patients.