Multivariate Cluster Analyses to Characterize Asthma Heterogeneity and Benralizumab Responsiveness.

BACKGROUND: An improved understanding of how severe asthma heterogeneity affects response could inform treatment decisions. OBJECTIVES: Characterize heterogeneity and benralizumab responsiveness in patients grouped by predefined Severe Asthma Research Program clusters using a multivariate approach. METHODS: In post-hoc analyses of the randomized, double-blind, placebo-controlled phase III SIROCCO (NCT01928771) and CALIMA (NCT01914757) studies, patients with severe asthma who received benralizumab or placebo were assigned to clusters using an established discriminant function to simultaneously analyze 11 clinical characteristics. Annualized asthma exacerbation rate, exacerbation incidence, and lung function were analyzed across clusters. RESULTS: Patients (N = 2,281) met criteria for 4 of 5 clusters: Cluster 2 (early-onset moderate asthma, n = 393), Cluster 4 (early-onset severe, n = 386), Cluster 3 (late-onset severe, n = 641), and Cluster 5 (late-onset severe, obstructed, n = 861); no patients met Cluster 1 criteria. Exacerbation rate reductions were significant in late-onset severe (-48% [95% CI: -61%, -31%], P<.0001) and late-onset severe, obstructed asthma (-50% [95% CI: -59%, -38%], P<.0001), with non-significant reductions in early-onset clusters. These differences could not be fully explained by blood eosinophil count differences. Forced expiratory volume in 1 second improvements were significant in late-onset severe (+133 mL [95% CI: 66 mL, 200 mL], P=.0001) and late-onset severe, obstructed asthma (+160 mL [95% CI: 85 mL, 235 mL], P<.0001) while maintaining acute bronchodilator responsiveness. CONCLUSIONS: Benralizumab reduced exacerbations and improved lung function, primarily in late-onset asthma clusters. This multivariate approach to identify subphenotypes, potentially reflecting pathobiological mechanisms, can guide therapy beyond univariate approaches.

BAL Fluid Eosinophilia Associates With Chronic Lung Allograft Dysfunction Risk: A Multicenter Study.

BACKGROUND: Chronic lung allograft dysfunction (CLAD) is the leading cause of death among lung transplant recipients. Eosinophils, effector cells of type 2 immunity, are implicated in the pathobiology of many lung diseases, and prior studies suggest their presence associates with acute rejection or CLAD after lung transplantation. RESEARCH QUESTION: Does histologic allograft injury or respiratory microbiology correlate with the presence of eosinophils in BAL fluid (BALF)? Does early posttransplant BALF eosinophilia associate with future CLAD development, including after adjustment for other known risk factors? STUDY DESIGN AND METHODS: We analyzed BALF cell count, microbiology, and biopsy data from a multicenter cohort of 531 lung recipients with 2,592 bronchoscopies over the first posttransplant year. Generalized estimating equation models were used to examine the correlation of allograft histology or BALF microbiology with the presence of BALF eosinophils. Multivariable Cox regression was used to determine the association between ≥ 1% BALF eosinophils in the first posttransplant year and definite CLAD. Expression of eosinophil-relevant genes was quantified in CLAD and transplant control tissues. RESULTS: The odds of BALF eosinophils being present was significantly higher at the time of acute rejection and nonrejection lung injury histologies and during pulmonary fungal detection. Early posttransplant ≥ 1% BALF eosinophils significantly and independently increased the risk for definite CLAD development (adjusted hazard ratio, 2.04; P = .009). Tissue expression of eotaxins, IL-13-related genes, and the epithelial-derived cytokines IL-33 and thymic stromal lymphoprotein were significantly increased in CLAD. INTERPRETATION: BALF eosinophilia was an independent predictor of future CLAD risk across a multicenter lung recipient cohort. Additionally, type 2 inflammatory signals were induced in established CLAD. These data underscore the need for mechanistic and clinical studies to clarify the role of type 2 pathway-specific interventions in CLAD prevention or treatment.

Clinical Implications of Longitudinal Blood Eosinophil Counts in Patients With Severe Asthma.

BACKGROUND: The stability and variability of blood eosinophil counts (BECs) to phenotype patients with severe asthma is not fully understood. OBJECTIVE: This post hoc, longitudinal, pooled analysis of placebo-arm patients from 2 phase 3 studies evaluated the clinical implications of BEC stability and variability in moderate-to-severe asthma. METHODS: This analysis included patients from SIROCCO and CALIMA who received maintenance medium- to high-dosage inhaled corticosteroids plus long-acting ß2-agonists; 2:1 patients with BECs of 300 cells/µL or higher and less than 300 cells/µL were enrolled. The BECs were measured 6 times over 1 year in a centralized laboratory. Exacerbations, lung function, and Asthma Control Questionnaire 6 scores were documented across patients grouped by BEC (<300 cells/µL or ≥300 cells/µL) and variability (<80% or ≥80% BECs less than or greater than 300 cells/µL). RESULTS: Among 718 patients, 42.2% (n = 303) had predominantly high, 30.9% (n = 222) had predominantly low, and 26.9% (n = 193) had variable BECs. Prospective exacerbation rates (mean ± SD) were significantly greater in patients with predominantly high (1.39 ± 2.20) and variable (1.41 ± 2.09) BECs versus predominantly low (1.05 ± 1.66) BECs. Similar results were observed for the number of exacerbations while on placebo. CONCLUSIONS: Although patients with variable BECs had intermittently high and low BECs, they experienced similar exacerbation rates to the predominantly high group, which were greater than those in the predominantly low group. A high BEC supports an eosinophilic phenotype in clinical settings without additional measurements, whereas a low BEC requires repeated measurements because it could reflect intermittently high or predominantly low BECs.

The commutability of enzyme linked immunosorbent assays for the quantification of serum eosinophil-derived neurotoxin (EDN).

Eosinophil-derived neurotoxin (EDN) is a surrogate biomarker of eosinophil activation and has considerable potential as a precision medicine biomarker in diseases where eosinophils may play a causative role. Clinical data for EDN have been generated using different quantitative immunoassays, but comparisons between these individual data sets are challenging as no internationally recognised EDN standards or orthogonal methods exist. In this study we aimed to compare commercial EDN assays from ALPCO, MBL, LSBio and CUSABIO for sample commutability. Firstly, we analytically validated the ALPCO enzyme linked immunosorbent assay (ELISA) and demonstrated appropriate analytical characteristics, including an intra/inter-assay precision coefficient-of-variation of between 1.9 and 6.8%. EDN purified from blood proved to be a good quality control material, whereas recombinant EDN, expressed in E.coli, did not react in the ALPCO immunoassay. Using healthy and asthma patient serum samples we confirmed that the ALPCO assay correlated well with the MBL assay, with a coefficient of determination (R2) of 0.92. However, the results from LSBio and CUSABIO assays were not commutable to the other assays.

Novel mechanisms of action contributing to benralizumab's potent anti-eosinophilic activity.

BACKGROUND: Benralizumab is a humanised, anti-interleukin-5 receptor α monoclonal antibody with anti-eosinophilic activity. Lack of fucose (afucosylation) increases its affinity to CD16a and significantly enhances antibody-dependent cell-mediated cytotoxicity by natural killer (NK) cells. Although benralizumab proved clinically efficacious in clinical trials for patients with severe asthma and hypereosinophilic syndrome, in-depth characterisation of its anti-eosinophilic mechanisms of action remains elusive. METHODS: Here, we further investigated the mechanisms involved in benralizumab's anti-eosinophilic activities by employing relevant primary human autologous cell co-cultures and real-time-lapse imaging combined with flow cytometry. RESULTS: In the presence of NK cells, benralizumab induced potent eosinophil apoptosis as demonstrated by the upstream induction of Caspase-3/7 and upregulation of cytochrome c. In addition, we uncovered a previously unrecognised mechanism whereby benralizumab can induce eosinophil phagocytosis/efferocytosis by macrophages, a process called antibody-dependent cellular phagocytosis. Using live cell imaging, we unravelled the stepwise processes leading to eosinophil apoptosis and uptake by activated macrophages. Through careful observations of cellular co-culture assays, we identified a novel role for macrophage-derived tumour necrosis factor (TNF) to further enhance benralizumab-mediated eosinophil apoptosis through activation of TNF receptor 1 on eosinophils. TNF-induced eosinophil apoptosis was associated with cytochrome c upregulation, mitochondrial membrane depolarisation and increased Caspase-3/7 activity. Moreover, activated NK cells were found to amplify this axis through the secretion of interferon-γ, subsequently driving TNF expression by macrophages. CONCLUSIONS: Our data provide deeper insights into the timely appearance of events leading to benralizumab-induced eosinophil apoptosis and suggest that additional mechanisms may contribute to the potent anti-eosinophilic activity of benralizumab in vivo. Importantly, afucosylation of benralizumab strongly enhanced its potency for all mechanisms investigated.

Eosinophil-derived neurotoxin: A biologically and analytically attractive asthma biomarker.

There is a growing body of evidence for the utility of eosinophil-derived neurotoxin (EDN) as a biomarker in asthma, including association with eosinophilic airway inflammation, assessment of disease severity and potential for predicting pathogenic risks, including exacerbations. However, to interpret any biomarker data with confidence, it is first important to understand the preanalytical factors and biological variation that may affect its reliable measurement and results interpretation. In this study we defined the healthy serum EDN reference range for men and women as 1.98 to 26.10 ng/mL, with no significant gender differences. Smoking did not impact the mean EDN levels and no circadian rhythm was identified for EDN, unlike blood eosinophils (EOS) where levels peaked at 00:00h. EDN expression in different cell types was investigated and shown to occur primarily in eosinophils, indicating they are likely to be the main cellular repository for EDN. We also confirm that the quantification of serum EDN is not influenced by the type of storage tube used, and it is stable at ambient temperature or when refrigerated for at least 7 days and for up to one year when frozen at -20°C or -80°C. In summary, EDN is a stable biomarker that may prove useful in precision medicine approaches by enabling the identification of a subpopulation of asthma patients with activated eosinophils and a more severe form of the disease.

The relationship between airway immunoglobulin activity and eosinophils in COPD.

In chronic obstructive pulmonary disease (COPD), the effects of inhaled corticosteroids are predicted by blood eosinophil counts. We previously briefly reported increased immunoglobulin (Ig)A and IgM levels in bronchoalveolar lavage (BAL) of COPD patients with higher (eosinophilhigh ) compared to lower (eosinophillow ) blood eosinophils (>250/µL versus < 150/µL), suggesting differences in adaptive immune function. An inverse relationship exists between eosinophil counts and airway pathogenic bacteria levels. The mechanistic reasons for these associations between eosinophils, corticosteroids and pathogenic bacteria are unclear. IgA, IgM and IgG levels were assessed in BAL, bronchial biopsies and epithelium collected from eosinophilhigh (n = 20) and eosinophillow (n = 21) patients. Bronchial B-cell numbers were measured by immunohistochemistry. B-cell activity was assessed in bronchial samples and following exposure to BAL from eosinophilhigh and eosinophillow patients. BAL levels of non-typeable Haemophilus influenza (NTHi)-specific immunoglobulins were quantified. Results showed airway expression of IgA, IgG1 and IgM were lower in eosinophillow compared to eosinophilhigh patients, with lower levels of NTHi-specific IgA and IgM. Bronchial B-cell numbers were similar in both groups, but B-cell activity was lower in eosinophillow patients. In conclusion, COPD eosinophillow patients show differences in adaptive immune function compared to COPD eosinophilhigh patients. These differences may cause different microbiomes in these COPD phenotypes.

Eosinophils, basophils and type 2 immune microenvironments in COPD-affected lung tissue.

Although elevated blood or sputum eosinophils are present in many patients with COPD, uncertainties remain regarding the anatomical distribution pattern of lung-infiltrating eosinophils. Basophils have remained virtually unexplored in COPD. This study mapped tissue-infiltrating eosinophils, basophils and eosinophil-promoting immune mechanisms in COPD-affected lungs.Surgical lung tissue and biopsies from major anatomical compartments were obtained from COPD patients with severity grades Global Initiative for Chronic Obstructive Lung Disease stages I-IV; never-smokers/smokers served as controls. Automated immunohistochemistry and in situ hybridisation identified immune cells, the type 2 immunity marker GATA3 and eotaxins (CCL11, CCL24).Eosinophils and basophils were present in all anatomical compartments of COPD-affected lungs and increased significantly in very severe COPD. The eosinophilia was strikingly patchy, and focal eosinophil-rich microenvironments were spatially linked with GATA3+ cells, including type 2 helper T-cell lymphocytes and type 2 innate lymphoid cells. A similarly localised and interleukin-33/ST2-dependent eosinophilia was demonstrated in influenza-infected mice. Both mice and patients displayed spatially confined eotaxin signatures with CCL11+ fibroblasts and CCL24+ macrophages.In addition to identifying tissue basophilia as a novel feature of advanced COPD, the identification of spatially confined eosinophil-rich type 2 microenvironments represents a novel type of heterogeneity in the immunopathology of COPD that is likely to have implications for personalised treatment.

Sputum microbiomic clustering in asthma and chronic obstructive pulmonary disease reveals a Haemophilus-predominant subgroup.

BACKGROUND: Airway ecology is altered in asthma and chronic obstructive pulmonary disease (COPD). Anti-microbial interventions might have benefit in subgroups of airway disease. Differences in sputum microbial profiles at acute exacerbation of airways disease are reflected by the γProteobacteria:Firmicutes (γP:F) ratio. We hypothesized that sputum microbiomic clusters exist in stable airways disease, which can be differentiated by the sputum γP:F ratio. METHODS: Sputum samples were collected from 63 subjects with severe asthma and 78 subjects with moderate-to-severe COPD in a prospective single centre trial. Microbial profiles were obtained through 16S rRNA gene sequencing. Topological data analysis was used to visualize the data set and cluster analysis performed at genus level. Clinical characteristics and sputum inflammatory mediators were compared across the clusters. RESULTS: Two ecological clusters were identified across the combined airways disease population. The smaller cluster was predominantly COPD and was characterized by dominance of Haemophilus at genus level (n = 20), high γP:F ratio, increased H influenzae, low diversity measures and increased pro-inflammatory mediators when compared to the larger Haemophilus-low cluster (n = 121), in which Streptococcus demonstrated the highest relative abundance at the genus level. Similar clusters were identified within disease groups individually and the γP:F ratio consistently differentiated between clusters. CONCLUSION: Cluster analysis by airway ecology of asthma and COPD in stable state identified two subgroups differentiated according to dominance of Haemophilus. The γP:F ratio was able to distinguish the Haemophilus-high versus Haemophilus-low subgroups, whether the Haemophilus-high group might benefit from treatment strategies to modulate the airway ecology warrants further investigation.

Ability of Serum IgE Concentration to Predict Exacerbation Risk and Benralizumab Efficacy for Patients with Severe Eosinophilic Asthma.

INTRODUCTION: For patients with eosinophilic asthma with allergic characteristics, understanding the key drivers of exacerbations is important to identify optimal treatment strategies. Benralizumab is an interleukin-5 receptor alpha-directed cytolytic monoclonal antibody that significantly reduces exacerbation frequency for patients with severe, uncontrolled eosinophilic asthma. We evaluated the predictive value of baseline blood eosinophil counts vs. serum immunoglobulin E (IgE) concentrations on exacerbation risk and the association of these variables with benralizumab treatment effect. METHODS: Analyses were performed with data pooled from the phase III SIROCCO and CALIMA benralizumab trials. Crude annual asthma exacerbation rates (AERs) were determined for placebo as a function of baseline blood eosinophil counts and serum IgE concentrations with prespecified blood eosinophil count categories (< 150, ≥ 150 to < 300, ≥ 300 to < 450, ≥ 450 cells/µL) and IgE concentration quartiles (< 62.0, ≥ 62.0 to < 176.2, ≥ 176.2 to < 453.4, and ≥ 453.4 kU/L). We compared AERs for patients receiving benralizumab 30 mg every 8 weeks (first three doses every 4 weeks) vs. placebo for overlapping baseline blood eosinophil count categories and serum IgE concentration quartiles via a regression approach and by continuously using locally weighted regression smoothing analysis. RESULTS: Exacerbation risk for patients with severe asthma receiving placebo increased with increasing baseline blood eosinophil counts but not with increasing serum IgE concentrations. Addition of baseline atopy status did not influence the relationship between IgE concentrations and exacerbation risk for patients receiving placebo. Patients with blood eosinophil counts ≥ 300 cells/µL had consistent decreases in exacerbation risk with benralizumab relative to placebo across all serum IgE concentration quartiles. CONCLUSION: Baseline blood eosinophil counts, but not serum IgE concentrations, are an important predictor of exacerbation risk. Patients with severe eosinophilic asthma treated with benralizumab had consistent reductions in exacerbation risk, regardless of IgE concentrations. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: SIROCCO, NCT01928771; CALIMA, NCT01914757.

Many patients with severe asthma have elevated numbers of eosinophils (a subset of white blood cells) and raised serum concentrations of immunoglobulin E (IgE; antibodies). Elevated eosinophil counts together with IgE concentrations are associated with more frequent asthma attacks. Benralizumab is a drug that almost completely depletes eosinophils and significantly reduces asthma attacks for patients with severe, uncontrolled asthma and elevated blood eosinophil counts. The individual influence of eosinophils and IgE on benralizumab efficacy has been published. In this study, we further extend the analyses to evaluate the interrelationship of eosinophil counts and IgE concentrations with asthma attack frequency and benralizumab efficacy for patients with severe, uncontrolled asthma. We evaluated the association of blood eosinophil counts and IgE concentrations with asthma attack frequency for patients with severe asthma who received high-dosage inhaled corticosteroids plus additional controller medications but did not receive benralizumab in the benralizumab clinical trials. We observed that increased blood eosinophil counts were associated with greater asthma attack frequency, while serum IgE concentrations had no influence on asthma attack frequency. We also evaluated patients who received benralizumab and determined that benralizumab can reduce the occurrence of these attacks for patients with elevated blood eosinophil counts regardless of their serum IgE concentrations. Frequency of asthma attacks also decreased with benralizumab for patients with elevated serum IgE concentrations, but serum IgE concentrations did not influence benralizumab efficacy. Benralizumab is an efficacious treatment for patients with uncontrolled eosinophilic asthma, regardless of their IgE concentrations.

Predicting response to benralizumab in chronic obstructive pulmonary disease: analyses of GALATHEA and TERRANOVA studies.

BACKGROUND: Benralizumab did not significantly reduce exacerbations compared with placebo in the phase 3 GALATHEA and TERRANOVA trials of benralizumab for patients with chronic obstructive pulmonary disease (COPD). We aimed to identify clinical and physiological characteristics of patients with COPD that could help to identify people who are likely to have the greatest treatment effect with benralizumab. METHODS: We analysed individual study and pooled results from GALATHEA and TERRANOVA. At study enrolment, patients from GALATHEA and TERRANOVA were aged 40-85 years, had moderate to very severe airflow limitation, had elevated blood eosinophil counts, and at least two exacerbations or one severe exacerbation in the previous year despite dual inhaled therapy (inhaled corticosteroids plus long-acting ß2-agonists or long-acting ß2-agonists plus long-acting muscarinic antagonists) or triple inhaled therapy (inhaled corticosteroids plus long-acting ß2-agonists plus long-acting muscarinic antagonists). We analysed data for 3910 patients who received benralizumab (30 mg or 100 mg subcutaneously every 8 weeks; first three doses every 4 weeks) or placebo with dual or triple therapy to identify factors consistently associated with annual exacerbation rate reduction. We evaluated the annual exacerbation rate for benralizumab versus placebo as the primary endpoint. GALATHEA and TERRANOVA are registered with ClinicalTrials.gov, NCT02138916 and NCT02155660, respectively. FINDINGS: For 2665 patients with elevated blood eosinophil counts, treatment effect with benralizumab every 8 weeks at 100 mg, but not at 30 mg, occurred for patients with a history of more frequent exacerbations, poorer baseline lung function, or greater baseline lung function improvement with short-acting bronchodilators. Patients with baseline blood eosinophil counts of 220 cells per µL or greater with: three or more exacerbations in the previous year receiving benralizumab every 8 weeks versus placebo, had rate ratios (RRs) of 0·69 (95% CI 0·56-0·83) for 100 mg and 0·86 (0·71-1·04) for 30 mg; postbronchodilator FEV1 of less than 40% had RRs of 0·76 (0·64-0·91) for 100 mg and 0·90 (0·76-1·06) for 30 mg; and postbronchodilator response of at least 15% had RRs of 0·67 (0·54-0·83) for 100 mg and 0·87 (0·71-1·07) for 30 mg. When combined factors were examined, patients with elevated baseline blood eosinophil counts, with three or more exacerbations in the previous year, and who were receiving triple therapy were identified as likely to benefit from benralizumab 100 mg every 8 weeks versus placebo (RR 0·70 [95% CI 0·56-0·88]). Benralizumab 30 mg every 8 weeks did not benefit patients meeting these criteria compared with placebo (RR 0·99 [95% CI 0·79-1·23]). INTERPRETATION: Elevated blood eosinophil counts combined with clinical characteristics identified a subpopulation of patients with COPD who had reductions in exacerbations with benralizumab treatment. These hypothesis-generating analyses identified the potential efficacy of benralizumab 100 mg for this subpopulation. These findings require prospective evaluation in clinical trials. FUNDING: AstraZeneca.

Sputum Streptococcus pneumoniae is reduced in COPD following treatment with benralizumab.

We hypothesized whether the reduction in eosinophilic airway inflammation in patients with chronic obstructive pulmonary disease (COPD) following treatment with benralizumab, a humanized, afucosylated, monoclonal antibody that binds to interleukin-5 receptor α, increases the airway bacterial load. Analysis of sputum samples of COPD patients participating in a Phase II trial of benralizumab indicated that sputum 16S rDNA load and Streptococcus pneumoniae were reduced following treatment with benralizumab. However, in vitro, eosinophils did not affect the killing of the common airway pathogens S. pneumoniae or Haemophilus influenzae. Thus, benralizumab may have an indirect effect upon airway bacterial load.

Benralizumab for the Prevention of COPD Exacerbations.

BACKGROUND: The efficacy and safety of benralizumab, an interleukin-5 receptor alpha-directed cytolytic monoclonal antibody, for the prevention of exacerbations in patients with moderate to very severe chronic obstructive pulmonary disease (COPD) are not known. METHODS: In the GALATHEA and TERRANOVA trials, we enrolled patients with COPD (at a ratio of approximately 2:1 on the basis of eosinophil count [≥220 per cubic millimeter vs. <220 per cubic millimeter]) who had frequent exacerbations despite receiving guideline-based inhaled treatment. Patients were randomly assigned to receive benralizumab (30 or 100 mg in GALATHEA; 10, 30, or 100 mg in TERRANOVA) every 8 weeks (every 4 weeks for the first three doses) or placebo. The primary end point was the treatment effect of benralizumab, measured as the annualized COPD exacerbation rate ratio (benralizumab vs. placebo) at week 56 in patients with baseline blood eosinophil counts of 220 per cubic millimeter or greater. Safety was also assessed. RESULTS: In GALATHEA, the estimates of the annualized exacerbation rate were 1.19 per year (95% confidence interval [CI], 1.04 to 1.36) in the 30-mg benralizumab group, 1.03 per year (95% CI, 0.90 to 1.19) in the 100-mg benralizumab group, and 1.24 per year (95% CI, 1.08 to 1.42) in the placebo group; the rate ratio as compared with placebo was 0.96 for 30 mg of benralizumab (P = 0.65) and 0.83 for 100 mg of benralizumab (P = 0.05). In TERRANOVA, the estimates of the annualized exacerbation rate for 10 mg, 30 mg, and 100 mg of benralizumab and for placebo were 0.99 per year (95% CI, 0.87 to 1.13), 1.21 per year (95% CI, 1.08 to 1.37), 1.09 per year (95% CI, 0.96 to 1.23), and 1.17 per year (95% CI, 1.04 to 1.32), respectively; the corresponding rate ratios were 0.85 (P = 0.06), 1.04 (P = 0.66), and 0.93 (P = 0.40). At 56 weeks, none of the annualized COPD exacerbation rate ratios for any dose of benralizumab as compared with placebo reached significance in either trial. Types and frequencies of adverse events were similar with benralizumab and placebo. CONCLUSIONS: Add-on benralizumab was not associated with a lower annualized rate of COPD exacerbations than placebo among patients with moderate to very severe COPD, a history of frequent moderate or severe exacerbations, and blood eosinophil counts of 220 per cubic millimeter or greater (Funded by AstraZeneca [GALATHEA and TERRANOVA] and Kyowa Hakko Kirin [GALATHEA]; GALATHEA and TERRANOVA ClinicalTrials.gov numbers, NCT02138916 and NCT02155660.).

Benralizumab for PDGFRA-Negative Hypereosinophilic Syndrome.

BACKGROUND: Hypereosinophilic syndrome is a group of diseases defined by marked eosinophilia in blood or tissue and eosinophil-related clinical manifestations. Benralizumab is a monoclonal antibody against interleukin-5 receptor α, which is expressed on human eosinophils. METHODS: In this randomized, double-blind, placebo-controlled, phase 2 trial, we administered a series of three monthly subcutaneous injections of either benralizumab (at a dose of 30 mg) or placebo in 20 symptomatic patients who had PDGFRA-negative hypereosinophilic syndrome and an absolute eosinophil count of at least 1000 cells per cubic millimeter; all the patients were receiving stable therapy (drugs or dietary changes) for this disease. This regimen was followed by an open-label phase, during which the patient's background therapy could be tapered as tolerated, and an extension phase. The primary end point of the randomized phase was a reduction of at least 50% in the absolute eosinophil count at week 12. RESULTS: During the randomized phase, the primary end point occurred in more patients in the benralizumab group than in the placebo group (9 of 10 patients [90%] vs. 3 of 10 patients [30%], P = 0.02). During the open-label phase, clinical and hematologic responses were observed in 17 of 19 patients (89%) and were sustained for 48 weeks in 14 of 19 patients (74%); in the latter group, in 9 of 14 patients (64%), background therapies could be tapered. Bone marrow and tissue eosinophilia were also suppressed with benralizumab therapy. The most common drug-related adverse events, headache and an elevated lactate dehydrogenase level, occurred in 32% of the patients after the first dose of benralizumab and resolved within 48 hours in all patients. Other adverse events occurred with similar frequency in the two groups. Of the many potential predictors of response that were examined, only clinical disease subtype appeared to be associated with the initial response or relapse. CONCLUSIONS: In this small phase 2 trial, patients with PDGFRA-negative hypereosinophilic syndrome who received benralizumab for 12 weeks had lower absolute eosinophil counts than those who received placebo. During the open-label phase, clinical and hematologic responses were sustained for 48 weeks in 74% of the patients. Adverse events did not limit treatment. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov numbers, NCT00001406 and NCT02130882.).

Modulation of blood inflammatory markers by benralizumab in patients with eosinophilic airway diseases.

BACKGROUND: Benralizumab, a humanized, afucosylated, monoclonal antibody that targets interleukin-5 receptor α, depletes eosinophils and basophils by enhanced antibody-dependent cell-mediated cytotoxicity. It demonstrated efficacy for patients with moderate to severe asthma and, in a Phase IIa trial, for chronic obstructive pulmonary disease (COPD) with eosinophilic inflammation. We investigated effects of benralizumab 100 mg every 8 weeks (first three doses every 4 weeks) subcutaneous on blood inflammatory markers through proteomic and gene-expression analyses collected during two Phase II studies of patients with eosinophilic asthma and eosinophilic COPD. METHODS: Serum samples for proteomic analysis and whole blood for gene expression analysis were collected at baseline and 52 weeks (asthma study) or 32 weeks (COPD study) post-treatment. Proteomic analyses were conducted on a custom set of 90 and 147 Rules-Based Medicine analytes for asthma and COPD, respectively. Gene expression was profiled by Affymetrix Human Genome U133 plus 2 arrays (~ 54 K probes). Gene set variation analysis (GSVA) was used to determine transcriptomic activity of immune signatures. Treatment-related differences between analytes, genes, and gene signatures were analyzed for the overall population and for patient subgroups stratified by baseline blood eosinophil count (eosinophil-high [≥300 cells/µL] and eosinophil-low [< 300 cells/µL]) via t-test and repeated measures analysis of variance. RESULTS: Eosinophil chemokines eotaxin-1 and eotaxin-2 were significantly upregulated (false discovery rate [FDR] < 0.05) by approximately 2.1- and 1.4-fold in the asthma study and by 2.3- and 1.7-fold in the COPD study following benralizumab treatment. Magnitude of upregulation of these two chemokines was greater for eosinophil-high patients than eosinophil-low patients in both studies. Benralizumab was associated with significant reductions (FDR < 0.05) in expression of genes associated with eosinophils and basophils, such as CLC, IL-5Rα, and PRSS33; immune-signaling complex genes (FCER1A); G-protein-coupled receptor genes (HRH4, ADORA3, P2RY14); and further immune-related genes (ALOX15 and OLIG2). The magnitude of downregulation of gene expression was greater for eosinophil-high than eosinophil-low patients. GSVA on immune signatures indicated significant treatment reductions (FDR < 0.05) in eosinophil-associated signatures. CONCLUSIONS: Benralizumab is highly selective, modulating blood proteins or genes associated with eosinophils or basophils. Modulated protein and gene expression patterns are most prominently altered in eosinophil-high vs. eosinophil-low patients. TRIAL REGISTRATION: NCT01227278 and NCT01238861 .

Periostin and Dipeptidyl Peptidase-4: Potential Biomarkers of Interleukin 13 Pathway Activation in Asthma and Allergy.

Periostin and dipeptidyl peptidase-4 (DPP-4) are proteins induced by type 2 cytokines interleukin (IL)-4 and IL-13 and show increased expression in asthma and diseases with type 2 inflammation, including atopic dermatitis and chronic rhinosinusitis. Both proteins can also be induced by other stimuli, such as profibrotic factors, which may confound their specificity as biomarkers of IL-13 pathway activation and type 2-driven disease. DPP-4 is important in glucose metabolism; therefore, serum concentrations may be confounded by the presence of concomitant metabolic disease. This review evaluates the potential of these biomarkers for anti-IL-13-directed therapy in asthma and diseases with type 2 inflammation.

Seasonal variability of exacerbations of severe, uncontrolled eosinophilic asthma and clinical benefits of benralizumab.

BACKGROUND: Benralizumab is a humanized, afucosylated, monoclonal antibody that targets interleukin-5 receptor alpha and induces direct, rapid, and nearly complete depletion of eosinophils via enhanced antibody-dependent cell-mediated cytotoxicity. In the United States, benralizumab is indicated for add-on maintenance treatment of patients ≥12 years old with severe asthma and an eosinophilic phenotype. OBJECTIVE: This study evaluated the effect of benralizumab treatment on seasonal asthma exacerbation rates for patients with severe, uncontrolled asthma. METHODS: This was a post hoc analysis of pooled data from the phase III SIROCCO (ClinicalTrials.gov identifier: NCT01928771) and CALIMA (NCT01914757) trials. The primary analysis population was patients ages 12-75 years treated with high-dosage inhaled corticosteroids and long-acting beta-2 agonists who had baseline blood eosinophil counts of ≥300 cells/µL. Patients received benralizumab 30 mg subcutaneously every 4 weeks or every 8 weeks (the first three doses every 4 weeks) or placebo every 4 weeks. Crude exacerbation rates (asthma exacerbations per patient-year) were determined for each month and season. Marginal asthma exacerbation rates and exacerbation rate ratios were estimated by season or month by using a negative binomial model that included covariates for study code, treatment, region, use of maintenance oral corticosteroids, and number of exacerbations in the previous year. Hemispheric seasons were accounted for by normalizing the study site locations. RESULTS: Observed crude exacerbation rates were higher in the fall and winter than in the spring and summer for all the patients. For the patients who received placebo, benralizumab every 4 weeks, and benralizumab every 8 weeks, crude exacerbation rates were the following: fall, 1.52, 0.86, and 0.81, respectively; winter, 1.44, 0.91, and 0.82, respectively; spring, 1.11, 0.66, and 0.52, respectively; and summer, 1.02, 0.55, and 0.51, respectively. Rate reductions in seasonal marginal annual exacerbation rates were 37-50% versus placebo at each season (p < 0.001). CONCLUSION: Benralizumab significantly and consistently reduced asthma exacerbations across all seasons versus placebo for patients with severe, uncontrolled eosinophilic asthma.

Baseline patient factors impact on the clinical efficacy of benralizumab for severe asthma.

Benralizumab is an anti-eosinophilic monoclonal antibody that reduces exacerbations and improves lung function for patients with severe, uncontrolled asthma with eosinophilic inflammation. We evaluated the impact of baseline factors on benralizumab efficacy for patients with severe asthma.This analysis used pooled data from the SIROCCO (ClinicalTrials.gov identifier NCT01928771) and CALIMA (ClinicalTrials.gov identifier NCT01914757) Phase III studies. Patients aged 12-75 years with severe, uncontrolled asthma receiving high-dosage inhaled corticosteroids plus long-acting ß2-agonists received benralizumab 30 mg subcutaneously every 8 weeks (Q8W, first three doses every 4 weeks (Q4W)), Q4W or placebo. Baseline factors that influenced benralizumab efficacy were evaluated, including oral corticosteroid (OCS) use, nasal polyposis, pre-bronchodilator forced vital capacity (FVC), prior year exacerbations and age at diagnosis. Efficacy outcomes included annual exacerbation rate and change in pre-bronchodilator forced expiratory volume in 1 s at treatment end relative to placebo.Benralizumab Q8W treatment effect was enhanced with each baseline factor for all patients and those with ≥300 eosinophils·µL-1 relative to the overall population. OCS use, nasal polyposis and FVC <65% of predicted were associated with greater benralizumab Q8W responsiveness for reduced exacerbation rate for patients with <300 eosinophils·µL-1Baseline clinical factors and blood eosinophil counts can help identify patients potentially responsive to benralizumab.