Mepolizumab was the first licensed anti-IL5 monoclonal antibody for severe eosinophilic asthma (SEA). To date there are few data to confirm its efficacy in the real-world setting or assessment of ...baseline characteristics associated with response.
How do patients with severe eosinophilic asthma respond to mepolizumab in the real world setting and which characteristics are associated with a super-response to this therapy?
We conducted a retrospective review of all patients who received at least 16 weeks of treatment with mepolizumab (100 mg subcutaneously) for SEA at our regional asthma center in the United Kingdom. Clinical data were collected at each 4-week visit. At 16, 24, and 52 weeks, patients were classified as “responders” or “nonresponders.” A response was defined as ≥50% reduction in exacerbations; for patients whose condition requires maintenance oral corticosteroids (mOCS), a response was defined as ≥50% reduction in prednisolone dose. Super responders were defined as exacerbation-free and off mOCS at one year.
Ninety-nine patients were included in the analysis. Asthma exacerbations decreased from a baseline of 4.04 ± 2.57 to 1.86 ± 2.17 per year at one year (54% reduction; P < .001). Sixty-eight patients were receiving mOCS at the time of commencing mepolizumab. By one year, the daily median dose fell from 10 mg (interquartile range, 10 to 15) to 0 mg (interquartile range, 0 to 10; P < .001). Fifty-seven percent of them were able to discontinue mOCS; 72.7% (95% CI, 63.0 to 80.7) of the patients were classified as responders, and 28.3% (95% CI, 20.2 to 38.0) of the patients were classified as super responders. Baseline characteristics associated with responder and super responder status included the presence of nasal polyposis (P = .012), lower baseline Asthma Control Questionnaire 6 (P = .006), a lower BMI (P = .014), and, in those patients receiving mOCS, a significantly lower prednisolone dose at baseline (P = .005). At 16 weeks, the one-year responder status was correctly identified in 80.8% patients; by 24 weeks, this status rose to 92.9%.
In a real-world SEA cohort, treatment with mepolizumab reduced exacerbation frequency and mOCS requirements. Nasal polyposis, a lower BMI, and a lower maintenance prednisolone requirement at baseline were associated with better outcomes. Twelve-month response was identifiable in >90% of patients by week 24.
Benralizumab is an IL5-receptor monoclonal antibody licensed for the treatment of severe eosinophilic asthma (SEA). It has demonstrated efficacy in clinical trials in reducing asthma exacerbation ...rates and maintenance oral corticosteroids (mOCSs).
What is the real-world effectiveness of benralizumab and what baseline characteristics are associated with response to therapy?
We assessed outcomes in all SEA patients who began benralizumab treatment at our specialist center. At each dosing visit, exacerbation history, mOCS dose, spirometry, and Asthma Control Questionnaire (ACQ6) and Mini-Asthma Quality of Life Questionnaire (mAQLQ) scores were recorded. Response to treatment was defined as a reduction of ≥ 50% in annualized exacerbation rate (AER) or in mOCS dose after 48 weeks of treatment. Super response was defined as zero exacerbations and no mOCSs for asthma.
One hundred thirty patients were included in the analysis. At 48 weeks, a 72.8% reduction in AER was noted, from 4.92 ± 3.35 per year in the year preceding biologic treatment to 1.34 ± 1.71 per year (P < .001), including 57 patients (43.8%) who were exacerbation-free with benralizumab. In those receiving mOCSs (n = 74 56.9%), the median daily prednisolone dose fell from 10 mg (interquartile range, 5-20 mg) to 0 mg (interquartile range, 0-5 mg; P < .001), and 38 of 74 patients (51.4%) were able to discontinue mOCS therapy. Clinically and statistically significant improvements were found in ACQ6 scores, mAQLQ scores, and FEV1. Overall, 51 patients (39%) met the super responder definition and 112 patients (86%) met the responder definition. The optimal regression model of super responders vs other responders included baseline characteristics associated with a strongly eosinophilic phenotype and less severe disease. Eighteen patients (13.8%) were nonresponders to benralizumab. Evidence of chronic airway infection was observed in 6 of 18 patients, and an increase in the blood eosinophil count consistent with the development of anti-drug antibodies was observed in 5 of 18 patients.
In a large real-world SEA cohort, benralizumab led to significant improvements in all clinical outcome measures. A lack of response was seen in a minority of patients and should be a focus for future investigation.
Rhinovirus infection is a major cause of asthma exacerbations.
We studied nasal and bronchial mucosal inflammatory responses during experimental rhinovirus-induced asthma exacerbations.
We used ...nasosorption on days 0, 2–5 and 7 and bronchosorption at baseline and day 4 to sample mucosal lining fluid to investigate airway mucosal responses to rhinovirus infection in patients with allergic asthma (n=28) and healthy non-atopic controls (n=11), by using a synthetic absorptive matrix and measuring levels of 34 cytokines and chemokines using a sensitive multiplex assay.
Following rhinovirus infection asthmatics developed more upper and lower respiratory symptoms and lower peak expiratory flows compared to controls (all P<0.05). Asthmatics also developed higher nasal lining fluid levels of an anti-viral pathway (including IFN-γ, IFN-λ/IL-29, CXCL11/ITAC, CXCL10/IP10 and IL-15) and a type 2 inflammatory pathway (IL-4, IL-5, IL-13, CCL17/TARC, CCL11/eotaxin, CCL26/eotaxin-3) (area under curve day 0–7, all P<0.05). Nasal IL-5 and IL-13 were higher in asthmatics at day 0 (P<0.01) and levels increased by days 3 and 4 (P<0.01). A hierarchical correlation matrix of 24 nasal lining fluid cytokine and chemokine levels over 7days demonstrated expression of distinct interferon-related and type 2 pathways in asthmatics. In asthmatics IFN-γ, CXCL10/IP10, CXCL11/ITAC, IL-15 and IL-5 increased in bronchial lining fluid following viral infection (all P<0.05).
Precision sampling of mucosal lining fluid identifies robust interferon and type 2 responses in the upper and lower airways of asthmatics during an asthma exacerbation. Nasosorption and bronchosorption have potential to define asthma endotypes in stable disease and at exacerbation.
•Following rhinovirus infection asthmatics have increased interferons and type 2 inflammation in airway mucosal lining fluid.•Nasosorption cytokines and chemokines showed distinct pathways of interferon and type 2 inflammation in asthma.•Precision mucosal sampling has potential for stratifying molecular endotypes of asthma.•Validation of nasosorption and bronchosorption will be required for selection of asthmatics for therapy with biologics.
Experimental human rhinovirus (HRV) infection causes more severe upper and lower respiratory tract symptoms in allergic asthmatics than in healthy controls. There is greater induction of cytokines and chemokines in nasal and bronchial mucosal lining fluid (MLF) of asthmatics: with distinct pathways of type 2 and anti-viral/regulatory inflammation.
Subject to further validation, analysis of MLF may prove useful in stratification of patients with asthma, and the definition of molecular endotypes.
Interpretation
Nasosorption and bronchosorption are precision sampling methods with potential for widespread application in respiratory and other mucosal diseases (e.g. gastrointestinal diseases).
Biomarkers identified in nasosorption and bronchosorption samples will need to be validated compared to established airway sampling methods, in a range of asthma phenotypes, and with current and novel therapies.
Asthma is a chronic airway disease driven by complex genetic-environmental interactions. The role of epigenetic modifications in bronchial epithelial cells (BECs) in asthma is poorly understood.
We ...piloted genome-wide profiling of the enhancer-associated histone modification H3K27ac in BECs from people with asthma (
= 4) and healthy controls (
= 3).
We identified
= 4,321 (FDR < 0.05) regions exhibiting differential H3K27ac enrichment between asthma and health, clustering at genes associated predominately with epithelial processes (EMT). We identified initial evidence of asthma-associated Super-Enhancers encompassing genes encoding transcription factors (
) and enzymes regulating lipid metabolism (
). We integrated published datasets to identify epithelium-specific transcription factors associated with H3K27ac in asthma (
) and identify initial relationships between asthma-associated changes in H3K27ac and transcriptional profiles. Finally, we investigated the potential of CRISPR-based approaches to functionally evaluate H3K27ac-asthma landscape
by identifying guide-RNAs capable of targeting acetylation to asthma DERs and inducing gene expression (
).
Our small pilot study validates genome-wide approaches for deciphering epigenetic mechanisms underlying asthma pathogenesis in the airways.
Practical methods of monitoring innate immune mucosal responsiveness are lacking. Lipopolysaccharide (LPS) is a component of the cell wall of Gram negative bacteria and a potent activator of ...Toll-like receptor (TLR)-4. To measure LPS responsiveness of the nasal mucosa, we administered LPS as a nasal spray and quantified chemokine and cytokine levels in mucosal lining fluid (MLF).
We performed a 5-way cross-over, single blind, placebo-controlled study in 15 healthy non-atopic subjects (n = 14 per protocol). Doses of ultrapure LPS (1, 10, 30 or 100μg/100μl) or placebo were administered by a single nasal spray to each nostril. Using the recently developed method of nasosorption with synthetic adsorptive matrices (SAM), a series of samples were taken. A panel of seven cytokines/chemokines were measured by multiplex immunoassay in MLF. mRNA for intercellular cell adhesion molecule-1 (ICAM-1) was quantified from nasal epithelial curettage samples taken before and after challenge.
Topical nasal LPS was well tolerated, causing no symptoms and no visible changes to the nasal mucosa. LPS induced dose-related increases in MLF levels of IL-1β, IL-6, CXCL8 (IL-8) and CCL3 (MIP-1α) (AUC at 0.5 to 10h, compared to placebo, p<0.05 at 30 and 100μg LPS). At 100μg LPS, IL-10, IFN-α and TNF-α were also increased (p<0.05). Dose-related changes in mucosal ICAM-1 mRNA were also seen after challenge, and neutrophils appeared to peak in MLF at 8h. However, 2 subjects with high baseline cytokine levels showed prominent cytokine and chemokine responses to relatively low LPS doses (10μg and 30μg LPS).
Topical nasal LPS causes dose-dependent increases in cytokines, chemokines, mRNA and cells. However, responsiveness can show unpredictable variations, possibly because baseline innate tone is affected by environmental factors. We believe that this new technique will have wide application in the study of the innate immune responses of the respiratory mucosa.
Ultrapure LPS was used as innate immune stimulus in a human nasal challenge model, with serial sampling of nasal mucosal lining fluid (MLF) by nasosorption using a synthetic absorptive matrix (SAM), and nasal curettage of mucosal cells. A dose response could be demonstrated in terms of levels of IL-1β, IL-6, CXCL8 and CCL3 in MLF, as well as ICAM-1 mRNA in nasal curettage specimens, and levels of neutrophils in nasal lavage. Depending on higher baseline levels of inflammation, there were occasional magnified innate inflammatory responses to LPS.
Clinical Trials.gov NCT02284074.
Results Following RV infection in asthmatic patients, type I myeloid (m)DCs, which promote Th2 inflammation upon ex vivo allergen exposure, showed significantly increased recruitment to the airways ...at day 8 post infection (p=0.008).
Nature Communications 6: Article number: 10224 (2015); Published: 21 December 2015; Updated: 9 March 2016 In Fig. 5 of this article, the three dot plots in the first row of panel a contain black ...numerical labels that are incorrect, and light blue labels that are correct. A revised version of Fig. 5,with correct labels in black throughout, appears below.
Inhaled corticosteroids (ICS) achieve disease control in the majority of asthmatic patients, although adherence to prescribed ICS is often poor. Patients with severe eosinophilic asthma may require ...treatment with oral corticosteroids (OCS) and/or biologic agents such as mepolizumab. It is unknown if ICS adherence changes on, or alters clinical response to, biologic therapy.
We examined ICS adherence and clinical outcomes in OCS-dependent severe eosinophilic asthma patients who completed 1 year of mepolizumab therapy. The ICS medicines possession ratio (MPR) was calculated (the number of doses of ICS issued on prescription/expected number) for the year before and the year after biologic initiation. Good adherence was defined as MPR >0.75, intermediate 0.74-0.51 and poor <0.5. We examined outcomes after 12 months of biologic therapy, including OCS reduction and annualised exacerbation rate (AER), stratified by adherence to ICS on mepolizumab.
Out of 109 patients commencing mepolizumab, 91 who had completed 12 months of treatment were included in the final analysis. While receiving mepolizumab, 68% had good ICS adherence, with 16 (18%) having poor ICS adherence. ICS use within the cohort remained similar before (MPR 0.81±0.32) and during mepolizumab treatment (0.82±0.32; p=0.78). Patients with good adherence had greater reductions in OCS dose (median (interquartile range) OCS reduction 100 (74-100)%
60 (27-100)%; p=0.031) and exacerbations (AER change -2.1±3.1
0.3±2.5; p=0.011) than those with poor adherence. Good ICS adherence predicted the likelihood of stopping maintenance OCS (adjusted OR 3.19, 95% CI 1.02-9.94; p=0.045).
ICS nonadherence is common in severe eosinophilic asthma patients receiving mepolizumab, and is associated with a lesser reduction in OCS requirements and AER.
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