Christine Ward

Benralizumab, an anti-interleukin 5 receptor α monoclonal antibody, versus placebo for uncontrolled eosinophilic asthma: a phase 2b randomised dose-ranging study

BACKGROUND Persistent eosinophilic airway inflammation in asthma increases the risk of exacerbations. In a phase 2b dose-ranging study, we aimed to assess the efficacy and safety of benralizumab, an anti-interleukin 5 receptor α monoclonal antibody that depletes blood and airway eosinophils, in adults with uncontrolled eosinophilic asthma. METHODS We did a randomised, controlled, double-blind, dose-ranging phase 2b study. Eligible participants were adults aged 18-75 years with uncontrolled asthma using medium-dose or high-dose inhaled corticosteroids and longacting β agonists, with two to six exacerbations in the past year. Current or former smokers were excluded. We used the ELEN index (an algorithm to predict elevated sputum eosinophils) or baseline fraction of exhaled nitric oxide to stratify patients by eosinophilic status, and with an interactive web-voice response system randomly assigned eosinophilic individuals in a 1:1:1:1 ratio to receive placebo, 2 mg benralizumab, 20 mg benralizumab, or 100 mg benralizumab, and non-eosinophilic individuals in a 1:1 ratio to receive placebo or 100 mg benralizumab. Study drugs were given as two subcutaneous injections every 4 weeks for the first three doses, then every 8 weeks, for 1 year. Patients, treating physicians, and study investigators were masked to treatment allocation. The primary endpoint was annual exacerbation rate in eosinophilic individuals after 1 year of follow-up. Analysis was by modified intention to treat. This study was designed with a two-sided α of 0·2 and powered at 78% for the primary outcome in the eosinophilic population. This study is registered with ClinicalTrials.gov, number NCT01238861. FINDINGS Between Jan 3, 2011, and March 6, 2012, we randomly assigned 324 eosinophilic individuals to placebo (n=80) or benralizumab 2 mg dose (n=81), 20 mg dose, (n=81), or 100 mg dose (n=82), and 285 non-eosinophilic individuals to 100 mg benralizumab (n=142, 140 included in analysis) or placebo (n=143, 142 included in analysis). In eosinophilic individuals, benralizumab reduced exacerbation rates compared with placebo in the 100 mg group (0·34 vs 0·57, reduction 41%, 80% CI 11 to 60, p=0·096) but not in the 2 mg group (0·65 vs 0·57, difference -9%, 80% CI -59 to 26, p=0·781) or the 20 mg group (0·37 vs 0·57, reduction 36%, 80% CI 3 to 58, p=0·173). In patients with a baseline blood eosinophil cutoff of at least 300 cells per μL, exacerbation rates in the benralizumab 20 mg group (n=70) and 100 mg group (n=97) were lower than in the placebo group (n=83; 0·30 vs 0·68, reduction 57%, 80% CI 33 to 72, p=0·015 for 20 mg dose; 0·38 vs 0·68, difference 43%, 80% CI 18 to 60, p=0·049 for 100 mg dose). Our findings suggested that benralizumab 20 mg and 100 mg resided at the dose-response plateau. Treatment-emergent adverse events occurred in 277 (72%) of 385 participants receiving any benralizumab dose compared with 143 (65%) of 221 receiving placebo. Nasopharyngitis (44 [11%] patients receiving benralizumab vs 13 [6%] patients receiving placebo) and injection site reactions (60 [16%] vs eight [4%]) occurred more frequently with benralizumab than with placebo. INTERPRETATION Benralizumab at 20 mg and 100 mg doses seemed to reduce asthma exacerbations in adults with uncontrolled eosinophilic asthma and baseline blood eosinophils of at least 300 cells per μL, possibly due to targeting of the interleukin 5 receptor rather than interleukin 5 ligand. Further investigation of benralizumab treatment in phase 3 studies is warranted. FUNDING MedImmune.

Benralizumab for chronic obstructive pulmonary disease and sputum eosinophilia: a randomised, double-blind, placebo-controlled, phase 2a study

BACKGROUND Chronic obstructive pulmonary disease (COPD) is associated with eosinophilic airway inflammation in 10-20% of patients. Benralizumab, an anti-interleukin-5 receptor α monoclonal antibody, depletes blood and sputum eosinophils. We aimed to establish whether benralizumab reduces acute exacerbations of COPD in patients with eosinophilia and COPD. METHODS We did this randomised, double-blind, placebo-controlled, phase 2a study between Nov 18, 2010, and July 13, 2013, at 26 sites in the UK, Poland, Germany, Canada, the USA, Denmark, and Spain. Adults aged 40-85 years, with moderate-to-severe COPD, at least one acute exacerbation of COPD, and a sputum eosinophil count of 3·0% or more within the previous year, were randomly assigned (1:1) via computer-generated permuted block randomisation (block size of four), with an interactive voice or web-response system, to receive placebo or 100 mg benralizumab subcutaneously, every 4 weeks (three doses), then every 8 weeks (five doses) over 48 weeks. Study site personnel included in study assessments, participants, and data analysts, were masked to treatment allocation. The primary endpoint was the annualised rate of acute exacerbations of COPD at week 56, defined as the number of acute exacerbations divided by total duration of person-year follow-up. Secondary and exploratory endpoints included COPD-specific Saint Georges Respiratory Questionnaire (SGRQ-C), Chronic Respiratory Questionnaire self-administered standardised format (CRQ-SAS), pre-bronchodilator forced expiratory volume in 1 second (FEV1), and safety. We did a prespecified subgroup analysis by baseline blood eosinophil count. Analyses were by intention to treat and per-protocol. This trial is registered with ClinicalTrials.gov, number NCT01227278. FINDINGS We randomly assigned 101 patients to receive placebo (n=50) or benralizumab (n=51), of whom 88 (87%) patients completed the study. Six patients who completed the study were excluded from the per-protocol population because of major protocol violations; the per-protocol population thus included 82 patients. Benralizumab did not reduce the annualised rate of acute exacerbations of COPD compared with placebo in the per-protocol population, with rates of 0·95 (0·68-1·29; n=40) versus 0·92 (0·67-1·25; n=42). Mean pre-bronchodilator FEV1 change from baseline to week 56 was -0·06 L (SD 0·24) with placebo, and 0·13 L (0·41) with benralizumab (p=0·014). Numerical, albeit non-significant, improvement in acute exacerbations of COPD, SGRQ-C, CRQ-SAS, and FEV1 were greater in benralizumab-treated patients with baseline blood eosinophil concentrations of 200 cells per μL or more or 300 cells per μL or more. Incidence of treatment-emergent adverse events was similar between the two groups, with the most common events being respiratory disorders (31 [62%] of 50 patients given placebo vs 32 [63%] of 51 given benralizumab) and infections (28 [56%] vs 27 [53%]). A higher incidence of serious treatment-emergent adverse events were recorded in patients in the benralizumab group than in those in the placebo group (14 vs nine patients), although none of these events were considered by the investigator to be benralizumab related. INTERPRETATION Compared with placebo, benralizumab did not reduce the rate of acute exacerbations of COPD. However, the results of prespecified subgroup analysis support further investigation of benralizumab in patients with COPD and eosinophilia. FUNDING MedImmune.

Cigarette Smoke Silences Innate Lymphoid Cell Function and Facilitates an Exacerbated Type I Interleukin-33-Dependent Response to Infection

Cigarette smoking is a major risk factor for chronic obstructive pulmonary disease and is presumed to be central to the altered responsiveness to recurrent infection in these patients. We examined the effects of smoke priming underlying the exacerbated response to viral infection in mice. Lack of interleukin-33 (IL-33) signaling conferred complete protection during exacerbation and prevented enhanced inflammation and exaggerated weight loss. Mechanistically, smoke was required to upregulate epithelial-derived IL-33 and simultaneously alter the distribution of the IL-33 receptor ST2. Specifically, smoke decreased ST2 expression on group 2 innate lymphoid cells (ILC2s) while elevating ST2 expression on macrophages and natural killer (NK) cells, thus altering IL-33 responsiveness within the lung. Consequently, upon infection and release, increased local IL-33 significantly amplified type I proinflammatory responses via synergistic modulation of macrophage and NK cell function. Therefore, in COPD, smoke alters the lung microenvironment to facilitate an alternative IL-33-dependent exaggerated proinflammatory response to infection, exacerbating disease.

Novel antagonist antibody to TLR3 blocks poly(I:C)-induced inflammation in vivo and in vitro.

Toll-like receptor 3 (TLR3) binds and signals in response to dsRNA and poly(I:C), a synthetic double stranded RNA analog. Activation of TLR3 triggers innate responses that may play a protective or detrimental role in viral infections or in immune-mediated inflammatory diseases through amplification of inflammation. Two monoclonal antibodies, CNTO4685 (rat anti-mouse TLR3) and CNTO5429 (CDRs from CNTO4685 grafted onto a mouse IgG1 scaffold) were generated and characterized. These mAbs bind the extracellular domain of mouse TLR3, inhibit poly(I:C)-induced activation of HEK293T cells transfected with mTLR3, and reduce poly(I:C)-induced production of CCL2 and CXCL10 by primary mouse embryonic fibroblasts. CNTO5429 decreased serum IL-6 and TNFα levels post-intraperitoneal poly(I:C) administration, demonstrating in vivo activity. In summary, specific anti-mTLR3 mAbs have been generated to assess TLR3 antagonism in mouse models of inflammation.

IL-18 associated with lung lymphoid aggregates drives IFNγ production in severe COPD

BackgroundIncreased interferon gamma (IFNγ) release occurs in Chronic Obstructive Pulmonary Disease (COPD) lungs. IFNγ supports optimal viral clearance, but if dysregulated could increase lung tissue destruction.MethodsThe present study investigates which mediators most closely correlate with IFNγ in sputum in stable and exacerbating disease, and seeks to shed light on the spatial requirements for innate production of IFNγ, as reported in mouse lymph nodes, to observe whether such microenvironmental cellular organisation is relevant to IFNγ production in COPD lung.ResultsWe show tertiary follicle formation in severe disease alters the dominant mechanistic drivers of IFNγ production, because cells producing interleukin-18, a key regulator of IFNγ, are highly associated with such structures. Interleukin-1 family cytokines correlated with IFNγ in COPD sputum. We observed that the primary source of IL-18 in COPD lungs was myeloid cells within lymphoid aggregates and IL-18 was increased in severe disease. IL-18 released from infected epithelium or from activated myeloid cells, was more dominant in driving IFNγ when IL-18-producing and responder cells were in close proximity.ConclusionsUnlike tight regulation to control infection spread in lymphoid organs, this local interface between IL-18-expressing and responder cell is increasingly supported in lung as disease progresses, increasing its potential to increase tissue damage via IFNγ.