Treatment with anti-cytokine monoclonal antibodies can potentiate the target cytokine rather than neutralize its activity

Baicalin regulates Treg/Th17 cell imbalance by inhibiting autophagy in allergic rhinitis

BACKGROUND

Baicalin has many biological properties such as anti-oxidation and anti-allergy. The current study aimed to explore the effect of Baicalin on allergic rhinitis (AR) and its potential mechanism of action.

METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated by density gradient centrifugation. Expression levels of Th17 and Treg cells-related proteins in nasal mucosa and peripheral blood cells were detected by real-time quantitative PCR, flow cytometry and Western blot. The mice were randomly divided into Control, ovalbumin (OVA), l-Baicalin, H-Baicalin, DSGC, 3-MA, and H-Baicalin + Rapa groups. Changes of allergic rhinitis conditions and eosinophil infiltration of the mice were detected and scored by Diff-Quik staining, and histological changes were observed by Hematoxylin & Eosin (H&E) staining and Periodate Schiff (PAS) staining. Serological changes, expression levels of interleukin-17A (IL-17A), interleukin-10 (IL-10), eosinophilic cationic protein (ECP) and anti-OVA-specific antibodies were detected by Enzyme-linked immunosorbent assay (ELISA).

RESULTS

Clinical case analysis found that AR patients had a Th17/Treg imbalance and activated autophagy, however, Baicalin restored Th17/Treg cell balance and inhibited autophagy in vitro. in vivo experiments demonstrated that Baicalin inhibited OVA-induced allergic nasal symptoms and the activation of autophagy pathway, which was the same as the regulation of 3-MA, while Rapa could weaken the effects of H-baicalin. Moreover, Baicalin reduced the infiltration of different inflammatory cells of the nasal lavage fluid, prevented the damages to epithelial cells, and improved nasal mucosal thickness and mucus secretion. In addition, Baicalin regulated the balance of mouse anti-OVA-specific antibody levels and expressions of Th17/Treg-associated cytokines.

CONCLUSION

Our study revealed that Baicalin can be used to treat AR, and the effect is realized through inhibiting autophagy to regulate Th17/Treg cell differentiation.

An Injectable Cytokine Trap for Local Treatment of Autoimmune Disease

Systemic cytokine therapy is limited by toxicity due to activation of unwanted immune cells in off-target tissues. Injectable nanomaterials that interact with the immune system have potential to offer improved pharmacokinetics and cell specificity compared to systemic cytokine therapy by instead capturing and potentiating endogenous cytokine. Here we demonstrate the use of high aspect ratio polycaprolactone nanowires conjugated to cytokine-binding antibodies that assemble into porous matrices when injected into the subcutaneous space. Nanowires are well tolerated in vivo over several weeks, incite minimal foreign body response and resist clearance. Nanowires conjugated with JES6-1, an anti-interleukin-2 (IL-2) antibody, were designed to capture endogenous IL-2 and selectively activate tissue resident regulatory T cells (Tregs). Together these nanowire-antibody matrices were capable of sequestering endogenous IL-2 in the skin and were successful in rebalancing local immune compartments to a more suppressive, Treg-mediated phenotype in both wild type and transgenic murine autoimmune disease models.

Overlapping Effects of New Monoclonal Antibodies for Severe Asthma

Among the monoclonal antibodies (mAbs) developed for severe asthma treatment, three have already been marketed. Omalizumab was the first, more than 10 years ago; today, mepolizumab and reslizumab are also available in the European Union and the US. Omalizumab blocks free immunoglobulin E (IgE), mepolizumab and reslizumab block an interleukin (IL-5). In the near future, dupilumab and benralizumab are expected to emerge as two new alternatives. Benralizumab blocks the receptor for IL-5 (IL5-Rα) and has a direct cytotoxic effect on eosinophils, and dupilumab blocks the α-unit of the heterodimeric receptor for IL-4 and IL-13 (IL-4Rα); as a result, dupilumab can block both IL-4 and IL-13. The purpose of this manuscript is to present the pathophysiology of some immunological aspects of severe asthma, describe the adaptive and innate immunity arms as well as their interrelations (stressing the subordination of the adaptive arm to the innate arm), outline the pharmacologic effects of these mAbs, clarify the overlapping effects of the different mAbs, and discuss the differences between mAbs based on their target molecules. Based on the data presented, I propose omalizumab for patients with an allergic phenotype regardless of their peripheral eosinophilic count, and anti-IL-5 as an alternative in allergic patients with blood eosinophilia in which omalizumab has failed; anti-IL5 for patients with an eosinophilic phenotype and omalizumab as an alternative in patients in whom anti-IL5 fails and IgE ≥30 IU/mL (compassionate use). Omalizumab is also proposed for patients with severe chronic asthma allergic to seasonal allergens.

Blood Eosinophils as Biomarkers to Drive Treatment Choices in Asthma and COPD

BACKGROUND

Asthma and COPD are complex, heterogeneous conditions comprising a wide range of phenotypes, some of which are refractory to currently available treatments. Elucidation of these phenotypes and identification of biomarkers with which to recognize them and guide appropriate treatment remain a priority.

OBJECTIVE

This review describes the utility of blood eosinophils as a surrogate biomarker of eosinophilic airway inflammation, a common feature of specific asthma and COPD phenotypes. The role of blood eosinophils in airway disease is described, as is their relevance in reflecting airway eosinophilia. Each disease is discussed separately as the manner in which blood eosinophils might be used as biomarkers differs. Focusing on patients with severe disease (persistent eosinophilic asthma and exacerbating COPD), we evaluate evidence examining eosinophils as biomarkers.

RESULTS

In asthma, the rationale for using blood eosinophils to guide treatment is clearly defined, backed by prospective, well-controlled studies. Higher eosinophil counts identify patients with more severe disease and poorer outcomes, patients for whom biologic therapies targeting allergic and/or eosinophilic pathways are recommended. In COPD, the evidence is less robust. High blood eosinophil counts are a modest predictor of future exacerbations, and may predict a favourable response to ICS on top of LABA/LAMA, especially in patients with a history of frequent exacerbations.

CONCLUSION

Before extensive application in clinical practice, further evaluation of these findings in prospective clinical studies, and standardization of the appropriate thresholds of clinically relevant eosinophilia are needed, together with establishing whether single or multiple measurements are required in different clinical settings.

Efficacy and safety of benralizumab in patients with eosinophilic asthma: a meta-analysis of randomized placebo-controlled trials

Benralizumab is a monoclonal antibody that targets interleukin-5 receptor α to deplete blood eosinophils and improve the clinical outcomes of allergic asthma. We conducted a meta-analysis to evaluate the safety and efficacy of different doses of benralizumab in patients with eosinophilic asthma. All randomized controlled trials involving benralizumab treatment for patients with eosinophilic asthma, which were searched in PubMed, Embase, and the Cochrane Library published until January 2017, as well as the rate of asthmatic exacerbation, pulmonary functionality, asthma control, quality of life scores, and adverse events were included. Randomized-effect models were used in the meta-analysis to calculate the pooled mean difference, relative risks, and 95% confidence intervals. Five studies involving 1951 patients were identified. Compared with the placebo, benralizumab treatment demonstrated significant improvements in the forced expiratory volume in 1 s (FEV1), Asthma Quality of Life Questionnaire scores, decreased asthmatic exacerbation and Asthma Control Questionnaire-6 (ACQ-6) scores. Benralizumab treatment was also not associated with increased adverse events. These findings indicated that benralizumab can be safely used to improve FEV1, enhance patient symptom control and quality of life, and reduce the risk of exacerbations and ACQ-6 scores in patients with eosinophilic asthma. Furthermore, our meta-analysis showed that benralizumab with 30 mg (every eight weeks) dosage can improve the health-related quality of life and appear to be more effective than 30 mg (every four weeks) dosage. Overall, data indicated that the optimal dosing regimen for benralizumab was possibly 30 mg (every eight weeks).

dIvergEnt: How IgE Axis Contributes to the Continuum of Allergic Asthma and Anti-IgE Therapies

Asthma is an airway disease characterised by chronic inflammation with intermittent or permanent symptoms including wheezing, shortness of breath, chest tightness, and cough, which vary in terms of their occurrence, frequency, and intensity. The most common associated feature in the airways of patients with asthma is airway inflammation. In recent decades, efforts have been made to characterise the heterogeneous clinical nature of asthma. The interest in improving the definitions of asthma phenotypes and endotypes is growing, although these classifications do not always correlate with prognosis nor are always appropriate therapeutic approaches. Attempts have been made to identify the most relevant molecular and cellular biomarkers underlying the immunopathophysiological mechanisms of the disease. For almost 50 years, immunoglobulin E (IgE) has been identified as a central factor in allergic asthma, due to its allergen-specific nature. Many of the mechanisms of the inflammatory cascade underlying allergic asthma have already been elucidated, and IgE has been shown to play a fundamental role in the triggering, development, and chronicity of the inflammatory responses within the disease. Blocking IgE with monoclonal antibodies such as omalizumab have demonstrated their efficacy, effectiveness, and safety in treating allergic asthma. A better understanding of the multiple contributions of IgE to the inflammatory continuum of asthma could contribute to the development of novel therapeutic strategies for the disease.

An Update on Lymphocyte Subtypes in Asthma and Airway Disease

Inflammation is a hallmark of many airway diseases. Improved understanding of the cellular and molecular mechanisms of airway disease will facilitate the transition in our understanding from phenotypes to endotypes, thereby improving our ability to target treatments based on pathophysiologic characteristics. For example, allergic asthma has long been considered to be driven by an allergen-specific T helper 2 response. However, clinical and mechanistic studies have begun to shed light on the role of other cell subsets in the pathogenesis and regulation of lung inflammation. In this review, we discuss the importance of different lymphocyte subsets to asthma and other airway diseases, while highlighting the growing evidence that asthma is a syndrome that incorporates many immune phenotypes.

Benralizumab, an anti-interleukin-5 receptor α monoclonal antibody, as add-on treatment for patients with severe, uncontrolled, eosinophilic asthma (CALIMA): a randomised, double-blind, placebo-controlled phase 3 trial

BACKGROUND

Benralizumab is a humanised, afucosylated, anti-interleukin-5 receptor α monoclonal antibody that induces direct, rapid, and nearly complete depletion of eosinophils. We aimed to assess the efficacy and safety of benralizumab as add-on therapy for patients with severe, uncontrolled asthma and elevated blood eosinophil counts.

METHODS

In this randomised, double-blind, parallel-group, placebo-controlled, phase 3 study (CALIMA) undertaken at 303 sites in 11 countries, we enrolled patients aged 12-75 years with severe asthma uncontrolled by medium-dosage to high-dosage inhaled corticosteroids plus long-acting β₂-agonists (ICS plus LABA) and a history of two or more exacerbations in the previous year. Patients were randomly assigned (1:1:1) to receive 56 weeks of benralizumab 30 mg every 4 weeks (Q4W), benralizumab 30 mg every 8 weeks (Q8W; first three doses 4 weeks apart), or placebo (all subcutaneous injection). Patients were stratified (2:1) by baseline blood eosinophil counts 300 cells per μL or greater and less than 300 cells per μL, respectively. Patients and study centre staff were masked to treatment allocation. The primary endpoint was annual exacerbation rate ratio versus placebo for patients receiving high-dosage ICS plus LABA with baseline blood eosinophils 300 cells per μL or greater (intention-to-treat analysis). Key secondary endpoints were pre-bronchodilator forced expiratory volume in 1 s (FEV₁) and total asthma symptom score. This study is registered with ClinicalTrials.gov, number NCT01914757.

FINDINGS

Between Aug 21, 2013, and March 16, 2015, 2505 patients were enrolled, of whom 1306 patients were randomised; 425 patients were randomly assigned to and received benralizumab 30 mg Q4W, 441 to benralizumab 30 mg Q8W, and 440 to placebo. 728 patients were included in the primary analysis population. Benralizumab resulted in significantly lower annual exacerbation rates with the Q4W regimen (rate 0·60 [95% CI 0·48-0·74], rate ratio 0·64 [95% CI 0·49-0·85], p=0·0018, n=241) and Q8W regimen (rate 0·66 [95% CI 0·54-0·82], rate ratio 0·72 [95% CI 0·54-0·95], p=0·0188, n=239) compared with placebo (rate 0·93 [95% CI 0·77-1·12], n=248). Benralizumab also significantly improved pre-bronchodilator FEV₁ (Q4W and Q8W) and total asthma symptom score (Q8W only) in these patients. The most common adverse events were nasopharyngitis (90 [21%] in the Q4W group, 79 [18%] in the Q8W group, and 92 [21%] in the placebo group) and worsening asthma (61 [14%] in the Q4W group, 47 [11%] in the Q8W group, and 68 [15%] in the group).

INTERPRETATION

Benralizumab significantly reduced annual exacerbation rates and was generally well tolerated for patients with severe, uncontrolled asthma with blood eosinophils 300 cells per μL or greater. Our data further refine the patient population likely to receive the greatest benefit from benralizumab treatment.

FUNDING

AstraZeneca and Kyowa Hakko Kirin.

Efficacy and safety of benralizumab for patients with severe asthma uncontrolled with high-dosage inhaled corticosteroids and long-acting β2-agonists (SIROCCO): a randomised, multicentre, placebo-controlled phase 3 trial

BACKGROUND

Eosinophilia is associated with worsening asthma severity and decreased lung function, with increased exacerbation frequency. We assessed the safety and efficacy of benralizumab, a monoclonal antibody against interleukin-5 receptor α that depletes eosinophils by antibody-dependent cell-mediated cytotoxicity, for patients with severe, uncontrolled asthma with eosinophilia.

METHODS

We did a randomised, double-blind, parallel-group, placebo-controlled phase 3 study at 374 sites in 17 countries. We recruited patients (aged 12-75 years) with a physician-based diagnosis of asthma for at least 1 year and at least two exacerbations while on high-dosage inhaled corticosteroids and long-acting β₂-agonists (ICS plus LABA) in the previous year. Patients were randomly assigned (1:1:1) by an interactive web-based voice response system to benralizumab 30 mg either every 4 weeks (Q4W) or every 8 weeks (Q8W; first three doses every 4 weeks) or placebo Q4W for 48 weeks as add on to their standard treatment. Patients were stratified 2:1 according to blood eosinophil counts of at least 300 cells per μL and less than 300 cells per μL. All patients and investigators involved in patient treatment or clinical assessment were masked to treatment allocation. The primary endpoint was annual exacerbation rate ratio versus placebo, and key secondary endpoints were prebronchodilator forced expiratory volume in 1 s (FEV₁) and total asthma symptom score at week 48, for patients with blood eosinophil counts of at least 300 cells per μL. Efficacy analyses were by intention to treat (based on the full analysis set); safety analyses included patients according to study drug received. This study is registered with ClinicalTrials.gov, number NCT01928771.

FINDINGS

Between Sept 19, 2013, and March 16, 2015, 2681 patients were enrolled, 1205 of whom met the study criteria and were randomly assigned: 407 to placebo, 400 to benralizumab 30 mg Q4W, and 398 to benralizumab 30 mg Q8W. 267 patients in the placebo group, 275 in the benralizumab 30 mg Q4W group, and 267 in the benralizumab 30 mg Q8W group had blood eosinophil counts at least 300 cells per μL and were included in the primary analysis population. Compared with placebo, benralizumab reduced the annual asthma exacerbation rate over 48 weeks when given Q4W (rate ratio 0·55, 95% CI 0·42-0·71; p<0·0001) or Q8W (0·49, 0·37-0·64; p<0·0001). Both benralizumab dosing regimens significantly improved prebronchodilator FEV₁ in patients at week 48 compared with placebo (least-squares mean change from baseline: Q4W group 0·106 L, 95% CI 0·016-0·196; Q8W group 0·159 L, 0·068-0·249). Compared with placebo, asthma symptoms were improved by the Q8W regimen (least-squares mean difference -0·25, 95% CI -0·45 to -0·06), but not the Q4W regimen (-0·08, -0·27 to 0·12). The most common adverse events were worsening asthma (105 [13%] of 797 benralizumab-treated patients vs 78 [19%] of 407 placebo-treated patients) and nasopharyngitis (93 [12%] vs 47 [12%]).

INTERPRETATION

These results confirm the efficacy and safety of benralizumab for patients with severe asthma and elevated eosinophils, which are uncontrolled by high-dosage ICS plus LABA, and provide support for benralizumab to be an additional option to treat this disease in this patient population.

FUNDING

AstraZeneca and Kyowa Hakko Kirin.