Philip G. Bardin

Reslizumab for inadequately controlled asthma with elevated blood eosinophil counts: results from two multicentre, parallel, double-blind, randomised, placebo-controlled, phase 3 trials

BACKGROUND Elevated numbers of blood eosinophils are a risk factor for asthma exacerbations. Reslizumab is a humanised anti-interleukin 5 monoclonal antibody that disrupts eosinophil maturation and promotes programmed cell death. We aimed to assess the efficacy and safety of reslizumab in patients with inadequately controlled, moderate-to-severe asthma. METHODS We did two duplicate, multicentre, double-blind, parallel-group, randomised, placebo-controlled phase 3 trials. Both trials enrolled patients with asthma aged 12-75 years (from 128 clinical research centres in study 1 and 104 centres in study 2) from Asia, Australia, North America, South America, South Africa, and Europe, whose asthma was inadequately controlled by medium-to-high doses of inhaled corticosteroid based therapy and who had blood eosinophils of 400 cells per μL or higher and one or more exacerbations in the previous year. Patients were randomly assigned (1:1) to receive either intravenous reslizumab (3·0 mg/kg) or placebo every 4 weeks for 1 year by computerised central randomisation. Patients and investigators were masked to treatment assignment during the study. Each patient received a specific volume of study drug (reslizumab or matching placebo) on the basis of the patients body weight and randomly assigned treatment group. Additionally, the sponsors clinical personnel involved in the study were masked to the study drug identity until the database was locked for analysis and the treatment assignment revealed. The primary outcome was the annual frequency of clinical asthma exacerbations and was analysed by intention to treat. We assessed safety outcomes in the patients who had received one or more dose of the drug. The trials have been completed and are registered with ClinicalTrials.gov, numbers NCT01287039 (study 1) and NCT01285323 (study 2). FINDINGS Study 1 was done between April 12, 2011, and March 3, 2014 and study 2 between March 22, 2011, and April 9, 2014. Of 2597 patients screened, 953 were randomly assigned to receive either reslizumab (n=477 [245 in study 1 and 232 in study 2]) or placebo (n=476 [244 and 232]). In both studies, patients receiving reslizumab had a significant reduction in the frequency of asthma exacerbations (study 1: rate ratio [RR] 0·50 [95% CI 0·37-0·67]; study 2: 0·41 [0·28-0·59]; both p<0·0001) compared with those receiving placebo. Common adverse events on reslizumab were similar to placebo. The most common adverse events were worsening asthma symptoms (127 [52%] for placebo and 97 [40%] for reslizumab in study 1; 119 [51%] for placebo and 67 [29%] for reslizumab for study 2), upper respiratory tract infections (32 [13%] and 39 [16%]; 16 [7%] and eight [3%]), and nasopharyngitis (33 [14%] and 28 [11%]; 56 [24%] and 45 [19%]). Two patients in the reslizumab group had anaphylactic reactions; both responded to standard treatment at the study centre and resolved, and the patients were withdrawn from the study. INTERPRETATION These results support the use of reslizumab in patients with asthma and elevated blood eosinophil counts who are inadequately controlled on inhaled corticosteroid-based therapy. FUNDING Teva Branded Pharmaceutical Products R&D.

Absence of pulmonary aspiration of sinus contents in patients with asthma and sinusitis

The frequent association of asthma and paranasal sinusitis has been ascribed to a nasobronchial reflex, aspiration of sinus secretions, or enhanced beta-adrenergic blockade. We investigated possible pulmonary aspiration in a pilot study (eight patients) and follow-up study (13 patients) by means of a radionuclide technique. In the pilot study, the aim was to demonstrate aspiration as well as visibility of the radionuclide in the thorax during a period of 24 hours. The radionuclide was initially placed bronchoscopically in the bronchial tree in four patients and was still clearly visible in the same position after 24 hours in three patients. Aspiration from the nasopharynx was unequivocally demonstrated in two of four patients with depressed consciousness. The follow-up study population consisted of four patients with maxillary sinusitis only and nine patients with sinusitis and asthma. The radionuclide was placed in a maxillary sinus during therapeutic puncture. In the patients with only sinusitis as well as patients with asthma and sinusitis the radionuclide could be demonstrated in the maxillary sinus, nasopharynx, esophagus, and lower gastrointestinal tract during a 24-hour period. However, no pulmonary aspiration of radionuclide could be demonstrated in any patient. We conclude that seeding of the lower airways by mucopurulent secretions is unlikely to account for coexistent pulmonary disease. The association is probably related to generalized mucosal disease affecting both upper and lower airways.

Nuclear Localization of Dengue Virus Nonstructural Protein 5 Through Its Importin α/β–Recognized Nuclear Localization Sequences is Integral to Viral Infection

Dengue virus nonstructural protein 5 (NS5) is a large multifunctional protein with a central role in viral replication. We previously identified two nuclear localization sequences (NLSs) within the central region of dengue virus type‐2 (DENV‐2) NS5 (‘aNLS’ and ‘bNLS’) that are recognized by the importin α/β and importin β1 nuclear transporters, respectively. Here, we demonstrate the importance of the kinetics of NS5 nuclear localization to virus production for the first time and show that the aNLS is responsible. Site‐specific mutations in the bipartite‐type aNLS or bNLS region were introduced into a reporter plasmid encoding green fluorescent protein fused to the N‐terminus of DENV‐2 NS5, as well as into DENV‐2 genomic length complementary DNA. Mutation of basic residues in the highly conserved region of the bNLS did not affect nuclear import of NS5. In contrast, mutations in either basic cluster of the aNLS decreased NS5 nuclear accumulation and reduced virus production, with the greatest reduction observed for mutation of the second cluster (K387K388K389); mutagenesis of both clusters abolished NS5 nuclear import and DENV‐2 virus production completely. The latter appeared to relate to the impaired ability of virus lacking nuclear‐localizing NS5, as compared with wild‐type virus expressing nuclear‐localizing NS5, to reduce interleukin‐8 production as part of the antiviral response. The results overall indicate that NS5 nuclear localization through the aNLS is integral to viral infection, with significant implications for other flaviviruses of medical importance, such as yellow fever and West Nile viruses.

Persistence of rhinovirus RNA after asthma exacerbation in children

Background Rhinoviruses (RVs) are believed to cause most asthma exacerbations but their role in the severity of acute asthma and subsequent recovery of airway function is not defined. The importance of atopy in virus‐host interactions is also not clear.

Rhinovirus Induction of the CXC Chemokine Epithelial-Neutrophil Activating Peptide-78 in Bronchial Epithelium

Epithelial-neutrophil activating peptide-78 (ENA-78) induces neutrophil migration, an early response to viral infection. Rhinovirus serotype 16 (RV16) was used to infect primary bronchial epithelial cells and a cell line (BEAS-2B). Release of ENA-78 protein was measured by enzyme-linked immunosorbent assay, ENA-78 mRNA production was quantified by reverse-transcription polymerase chain reaction, and ENA-78 promoter activity was assessed by use of a promoter construct. After infection with RV16, ENA-78 protein and mRNA increased significantly, and RV16 induced 3-fold increases in ENA-78 gene transcription. Nasal ENA-78 measured in patients with asthma with and without RV infection was more elevated in patients with RV infection present. Our study demonstrates that ENA-78 is produced in bronchial epithelial cells in response to RV16 infection. With other chemokines, it may be an important initiator of neutrophil airway inflammation during RV common colds and thus may play a role in the development of virus-associated airway pathologies.

Laryngeal penetration and aspiration in individuals with stable COPD

Background and objective:  Swallowing is closely coordinated with breathing but in COPD altered synchronization may predispose patients to a breach of the upper airway protective mechanisms. However, aspiration during swallow has never been shown in COPD. We examined penetration of liquid material into the airway of patients with COPD and correlated it with breathing‐swallow patterns.

Abnormal vocal cord function in difficult-to-treat asthma.

RATIONALE Upper airway dysfunction may complicate asthma but has been largely ignored as an etiological factor. Diagnosis using endoscopic evaluation of vocal cord function is difficult to quantify, with limited clinical application. OBJECTIVES A novel imaging technique, dynamic 320-slice computerized tomography (CT), was used to examine laryngeal behavior in healthy individuals and individuals with asthma. METHODS Vocal cord movement was imaged using 320-slice CT larynx. Healthy volunteers were studied to develop and validate an analysis algorithm for quantification of normal vocal cord function. Further studies were then conducted in 46 patients with difficult-to-treat asthma. MEASUREMENTS AND MAIN RESULTS Vocal cord movement was quantified over the breathing cycle by CT using the ratio of vocal cord diameter to tracheal diameter. Normal limits were calculated, validated, and applied to evaluate difficult-to-treat asthma. Vocal cord movement was abnormal with excessive narrowing in 23 of 46 (50%) patients with asthma and severe in 9 (19%) patients (abnormal > 50% of inspiration or expiration time). Imaging also revealed that laryngeal dysfunction characterized the movement abnormality rather than isolated vocal cord dysfunction. CONCLUSIONS Noninvasive quantification of laryngeal movement was achieved using CT larynx. Significant numbers of patients with difficult-to-treat asthma had excessive narrowing of the vocal cords. This new approach has identified frequent upper airway dysfunction in asthma with potential implications for disease control and treatment.

Long-term safety of fluticasone furoate nasal spray in adults and adolescents with perennial allergic rhinitis

Background:  Fluticasone furoate is a novel‐enhanced affinity glucocorticoid and its long‐term safety must be assessed. This study was designed to assess the safety and tolerability of 12‐month intranasal administration of fluticasone furoate in adult and adolescent patients with perennial allergic rhinitis (PAR).

The Respiratory Syncytial Virus Matrix Protein Possesses a Crm1-Mediated Nuclear Export Mechanism

ABSTRACT The respiratory syncytial virus (RSV) matrix (M) protein is localized in the nucleus of infected cells early in infection but is mostly cytoplasmic late in infection. We have previously shown that M localizes in the nucleus through the action of the importin β1 nuclear import receptor. Here, we establish for the first time that Ms ability to shuttle to the cytoplasm is due to the action of the nuclear export receptor Crm1, as shown in infected cells, and in cells transfected to express green fluorescent protein (GFP)-M fusion proteins. Specific inhibition of Crm1-mediated nuclear export by leptomycin B increased M nuclear accumulation. Analysis of truncated and point-mutated M derivatives indicated that Crm1-dependent nuclear export of M is attributable to a nuclear export signal (NES) within residues 194 to 206. Importantly, inhibition of M nuclear export resulted in reduced virus production, and a recombinant RSV carrying a mutated NES could not be rescued by reverse genetics. That this is likely to be due to the inability of a nuclear export deficient M to localize to regions of virus assembly is indicated by the fact that a nuclear-export-deficient GFP-M fails to localize to regions of virus assembly when expressed in cells infected with wild-type RSV. Together, our data suggest that Crm1-dependent nuclear export of M is central to RSV infection, representing the first report of such a mechanism for a paramyxovirus M protein and with important implications for related paramyxoviruses.

Cyclosporin as a treatment for interstitial lung disease of unknown aetiology.

Ten patients with progressive, symptomatic interstitial lung disease of unknown aetiology who were treated with cyclosporin A were reviewed. Five had clinical and histopathological features of cryptogenic fibrosing alveolitis and five a progressive restrictive lung disease characterised by interstitial infiltration with lymphocytes and minimal fibrosis, which could not be classified precisely. Three patients with lymphocytic infiltration showed a response to initial treatment with cyclosporin A alone at high dosage, but toxicity precluded further treatment. All 10 patients then received low doses of cyclosporin A and prednisone. Three of the patients with cryptogenic fibrosing alveolitis and all five patients with lymphocytic infiltration responded with a reduction in dyspnoea or an increase in vital capacity, or both; cyclosporin A appeared to be effective, or at least to have a corticosteroid potentiating effect. A high incidence of side effects occurred, though these do not necessarily prohibit the long term use of cyclosporin A when it is indicated clinically. Cyclosporin A may be effective in the treatment of interstitial lung disease of unknown aetiology. Further studies are required to determine the long term outcome of treatment.