Asthma Clinical Trials Research Articles

Prophylactic benefits of systemically delivered simvastatin treatment in a house dust mite challenged murine model of allergic asthma.

Systemically delivered statins can blunt airway inflammation in ovalbumin-challenged mice. However, in asthma clinical trials the beneficial effects of introducing oral statins are not compelling. We have invetigated this discrepancy using a clinically relevant murine model of allergic asthma, and by including a prophylactic study arm. Adult mice were: 1) challenged with house dust mite (HDM) alone or with subcutaneous (s.c.) simvastatin for two weeks; or 2) also treated with simvastatin for one week prior to HDM challenge. We assayed lung function, inflammatory cell influx and cytokine profile, goblet cell abundance, and simvastatin concentration in serum, lung lavage and tissue. Ultrahigh performance liquid chromatography-tandem mass spectrometry revealed that pharmacologically active simvastatin reached peak serum concentration after 8h, but declined rapidly. Prophylactic treatment doubled peak serum simvastatin and repeated s.c. delivery established stable serum levels, but simvastatin was undetectable in the lungs. Both simvastatin treatment arms suppressed indices of HDM-induced airway inflammation and goblet cell hyperplasia, but this was significantly greater with prophylactic therapy, in particular, inhibition of neutrophil and eosinophil influx, and cytokine accumulation. Conversely, neither acute nor prophylactic delivery of simvastatin prevented HDM challenge-induced airway hyperreactivity. Systemically administered simvastatin accumulates in the blood, but not in lung tissues, and reduces leukocyte influx and associated lung inflammation. Prophylactic therapy has the greatest anti-inflammatory effects, but as observed in human clinical trials, systemic simvastatin therapy does not prevent allergic airway hyperreactivity.

Patient-reported outcomes in asthma clinical trials.

The review provides an overview of the results of asthma clinical trials published in peer review journals in the last 18 months that evaluated patient-reported outcomes (PROs). In the last 10 years, health care moved toward a patient-centered approach, which includes patients' perspectives reflecting the impact of a disease and its treatment. Surprisingly, among the almost 300 clinical trials published in the last one and a half year, PRO evaluation was performed in only 20 studies, and none of them held in a real-life setting. The effort of applying the scientific methods of PRO investigations in asthma clinical trials following a rigorous and systematic approach needs to be highly improved to allow better understanding of patient reported factors. Some recommendations are drawn particularly about PRO assessment in personalized medicine research. The ability of an individual PRO to evaluate choice of treatment and its effectiveness remains to be achieved.

Editorial introductions

Editorial introductions

CRTH2 antagonists in asthma: current perspectives.

Chemoattractant receptor-homologous molecule expressed on TH2 cells (CRTH2) binds to prostaglandin D2. CRTH2 is expressed on various cell types including eosinophils, mast cells, and basophils. CRTH2 and prostaglandin D2 are involved in allergic inflammation and eosinophil activation. Orally administered CRTH2 antagonists are in clinical development for the treatment of asthma. The biology and clinical trial data indicate that CRTH2 antagonists should be targeted toward eosinophilic asthma. This article reviews the clinical evidence for CRTH2 involvement in asthma pathophysiology and clinical trials of CRTH2 antagonists in asthma. CRTH2 antagonists could provide a practical alternative to biological treatments for patients with severe asthma. Future perspectives for this class of drug are considered, including the selection of the subgroup of patients most likely to show a meaningful treatment response.

Obesity's effect on asthma extends to diagnostic criteria

The use of inflammatory biomarkers to delineate the type of lung inflammation present in asthmatic subjects is increasingly common. However, the effect of obesity on these markers is unknown. We aimed to determine the effect of obesity on conventional markers of inflammation in asthmatic subjects. We performed secondary analysis of data from 652 subjects previously enrolled in 2 Asthma Clinical Research Network trials. We performed linear correlations between biomarkers and logistic regression analysis to determine the predictive value of IgE levels, blood eosinophil counts, and fraction of exhaled nitric oxide values in relationship to sputum eosinophil counts (>2%), as well as to determine whether cut points existed that would maximize the sensitivity and specificity for predicting sputum eosinophilia in the 3 weight groups. Overall, statistically significant but relatively weak correlations were observed among all 4 markers of inflammation. Within obese subjects, the only significant correlation found was between IgE levels and blood eosinophil counts (r=0.33, P<.001); furthermore, all other correlations between inflammatory markers were approximately 0, including correlations with sputum eosinophil counts. In addition, the predictive value of each biomarker alone or in combination was poor in obese subjects. In fact, in obese subjects none of the biomarkers of inflammation significantly predicted the presence of high sputum eosinophil counts. Obese asthmatic subjects have lower cut points for IgE levels (268 IU), fraction of exhaled nitric oxide values (14.5ppb), and blood eosinophil counts (96cells/μL) than all other groups. In obese asthmatic subjects conventional biomarkers of inflammation are poorly predictive of eosinophilic airway inflammation. As such, biomarkers currently used to delineate eosinophilic inflammation in asthmatic subjects should be approached with caution in these subjects.

Influence of chronic azithromycin treatment on the composition of the oropharyngeal microbial community in patients with severe asthma

BackgroundThis study of the oropharyngeal microbiome complements the previously published AZIthromycin in Severe ASThma (AZISAST) clinical trial, where the use of azithromycin was assessed in subjects with exacerbation-prone severe asthma. Here, we determined the composition of the oropharyngeal microbial community by means of deep sequencing of the amplified 16S rRNA gene in oropharyngeal swabs from patients with exacerbation-prone severe asthma, at baseline and during and after 6 months treatment with azithromycin or placebo.ResultsA total of 1429 OTUs were observed, of which only 59 were represented by more than 0.02% of the reads. Firmicutes, Bacteroidetes, Fusobacteria, Proteobacteria and Actinobacteria were the most abundant phyla and Streptococcus and Prevotella were the most abundant genera in all the samples. Thirteen species only accounted for two thirds of the reads and two species only, i.e. Prevotella melaninogenica and Streptococcus mitis/pneumoniae, accounted for one fourth of the reads.We found that the overall composition of the oropharyngeal microbiome in patients with severe asthma is comparable to that of the healthy population, confirming the results of previous studies. Long term treatment (6 months) with azithromycin increased the species Streptococcus salivarius approximately 5-fold and decreased the species Leptotrichia wadei approximately 5-fold. This was confirmed by Boruta feature selection, which also indicated a significant decrease of L. buccalis/L. hofstadtii and of Fusobacterium nucleatum. Four of the 8 treated patients regained their initial microbial composition within one month after cessation of treatment.ConclusionsDespite large diversity of the oropharyngeal microbiome, only a few species predominate. We confirm the absence of significant differences between the oropharyngeal microbiomes of people with and without severe asthma. Possibly, long term azithromycin treatment may have long term effects on the composition of the oropharygeal microbiome in half of the patients.

Fluctuation Metrics as Novel Endpoints for Clinical Trials in Asthma.

Fluctuation Metrics as Novel Endpoints for Clinical Trials in Asthma.

Interleukin-5 Inhibitors for Severe Asthma: Rationale and Future Outlook.

In this review, we outline the pathophysiology of severe asthma and discuss the role of anti-interleukin (IL)-5 inhibitors for the treatment of asthma. Anti-IL-5 treatments have shown efficacy in reducing the rate of severe asthma attacks in eosinophilic asthma. We review the history of the development of these agents, lessons learnt about severe asthma along the way and key clinical trials supporting efficacy of the three anti-IL-5 treatments that are clinically available or undergoing clinical trials in asthma.

A cognitive approach for design of a multimedia informed consent video and website in pediatric research

ObjectivePoor participant comprehension of research procedures following the conventional face-to-face consent process for biomedical research is common. We describe the development of a multimedia informed consent video and website that incorporates cognitive strategies to enhance comprehension of study related material directed to parents and adolescents. Materials and methodsA multidisciplinary team was assembled for development of the video and website that included human subjects professionals; psychologist researchers; institutional video and web developers; bioinformaticians and programmers; and parent and adolescent stakeholders. Five learning strategies that included Sensory-Modality view, Coherence, Signaling, Redundancy, and Personalization were integrated into a 15-min video and website material that describes a clinical research trial. ResultsA diverse team collaborated extensively over 15months to design and build a multimedia platform for obtaining parental permission and adolescent assent for participant in as asthma clinical trial. Examples of the learning principles included, having a narrator describe what was being viewed on the video (sensory-modality); eliminating unnecessary text and graphics (coherence); having the initial portion of the video explain the sections of the video to be viewed (signaling); avoiding simultaneous presentation of text and graphics (redundancy); and having a consistent narrator throughout the video (personalization). DiscussionExisting conventional and multimedia processes for obtaining research informed consent have not actively incorporated basic principles of human cognition and learning in the design and implementation of these processes. The present paper illustrates how this can be achieved, setting the stage for rigorous evaluation of potential benefits such as improved comprehension, satisfaction with the consent process, and completion of research objectives. ConclusionNew consent strategies that have an integrated cognitive approach need to be developed and tested in controlled trials.

Disease Burden of Patients with Asthma/COPD Overlap in a US Claims Database: Impact of ICD-9 Coding-based Definitions

ABSTRACTThe inclusion of an asthma/chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) population in the 2015 Global Initiative for Chronic Obstructive Lung Disease strategic documents has raised questions about the profile of these patients in clinical practice, as they are mostly excluded from asthma and COPD clinical trials. We estimated the disease burden, co-morbidities, and respiratory treatments of patients with asthma/COPD overlap, utilizing the Truven MarketScan commercial and Medicare databases. Patients with ≥1 COPD or chronic obstructive asthma diagnostic code were identified between January 1, 2008, and December 31, 2011. The asthma/COPD overlap group was defined and stratified based upon type and frequency of asthma diagnostic code (chronic obstructive asthma only, COPD and chronic obstructive asthma, and COPD and ≥1 asthma code). 1,488,613 patients were identified; of these, 1,171,626 were diagnosed with COPD alone and 316,987 with asthma/COPD overlap. Patients with asthma and COPD had higher disease burden indicators and inhaled corticosteroid/long-acting beta-agonist use compared with COPD alone. This trend was consistent for all definitions of asthma/COPD overlap. Patients with obstructive asthma and COPD tended to be older, with greater disease burden compared with other definitions; this population may represent a more severe form of asthma/COPD overlap. Disease burden and treatment also varied based on the codes defining asthma/COPD overlap, indicating possible phenotypic differences. More clinical insight and detailed phenotyping is needed to determine the reasons for coding variation in asthma/COPD overlap, with implications for further research to address unmet needs.

Pharmacokinetics of tiotropium administered by Respimat® in asthma patients: Analysis of pooled data from Phase II and III clinical trials

Tiotropium is a long-acting inhaled antimuscarinic bronchodilator that has recently received marketing authorization for the indication of asthma with dose delivery via the Respimat® inhaler, in addition to its widely established role in the management of chronic obstructive pulmonary disease (COPD). This report presents a combined analysis of tiotropium plasma and urine pharmacokinetics at steady state from 8 Phase II/III clinical trials in asthma and delineates the effects of patient characteristics on systemic exposure based on the parameters fe0-24,ss (fraction of dose excreted unchanged in urine over 24 h post-dose at steady-state) and dose-normalized AUCtau,ss and Cmax,ss. Pharmacokinetics were also compared between asthma and COPD, incorporating data from 3 COPD Phase II/III clinical trials. Tiotropium pharmacokinetics in asthma were dose-proportional up to 5 μg dosed once daily. The following factors showed no statistically significant effects on tiotropium systemic exposure in asthma based on analysis of geometric mean ratios and 90% confidence intervals: age, asthma severity, lung function, reversibility testing, allergy status, smoking history, geographical region, and posology (5 μg once daily or 2.5 μg twice daily via Respimat®). Asian patients showed a moderately but significantly higher systemic exposure compared to White or Black patients. However, no differences in safety by race were observed. Total systemic exposure (AUCtau,ss) was similar between asthma and COPD, but Cmax,ss was 52% lower in asthma patients compared to COPD. It is concluded that in asthma, patient characteristics have no relevant effect on tiotropium systemic exposure. Since systemic exposure to inhaled drugs is an indicator of safety, the lower Cmax,ss compared to COPD is not considered a concern for tiotropium therapy of asthma.

A randomized study of a method for optimizing adolescent assent to biomedical research

ABSTRACTPurpose: Voluntary consent/assent with adolescents invited to participate in research raises challenging problems. No studies to date have attempted to manipulate autonomy in relation to assent/consent processes. This study evaluated the effects of an autonomy-enhanced individualized assent/consent procedure embedded within a randomized pediatric asthma clinical trial. Methods: Families were randomly assigned to remain together or separated during a consent/assent process; the latter we characterize as an autonomy-enhanced assent/consent procedure. We hypothesized that separating adolescents from their parents would improve adolescent assent by increasing knowledge and appreciation of the clinical trial and willingness to participate. Results: Sixty-four adolescent–parent dyads completed procedures. The together versus separate randomization made no difference in adolescent or parent willingness to participate. However, significant differences were found in both parent and adolescent knowledge of the asthma clinical trial based on the assent/consent procedure and adolescent age. The separate assent/consent procedure improved knowledge of study risks and benefits for older adolescents and their parents but not for the younger youth or their parents. Regardless of the assent/consent process, younger adolescents had lower comprehension of information associated with the study medication and research risks and benefits, but not study procedures or their research rights and privileges. Conclusions: The use of an autonomy-enhanced assent/consent procedure for adolescents may improve their and their parent's informed assent/consent without impacting research participation decisions. Traditional assent/consent procedures may result in a “diffusion of responsibility” effect between parents and older adolescents, specifically in attending to key information associated with study risks and benefits.

Lessons learned from clinical trials of asthma.

Exacerbations of persistent or intermittent asthma should be anticipated by physicians and health-care professionals. Patients who are likely to experience an exacerbation often have a history of an exacerbation in the previous year, and the absolute eosinophil count in peripheral blood is ≥ 400/μL. Similarly, expectorated or induced sputum eosinophilia of ≥2% is associated with exacerbations. These phenotypic findings have led to effective biologic therapies, which target eosinophils or immunoglobulin E or the T-helper type 2 phenotype, especially in children, adolescents, and adults with frequent exacerbations. In children, a reduced forced expiratory volume in the first second of expiration (FEV1) to forced vital capacity ratio can be associated with future exacerbations, although the FEV1 may be in the normal range, even with children who have persistent severe asthma. Asthma control questionnaires did not differentiate between children with or children without a future exacerbation. Alternatively, in adults, the lower baseline FEV1 (2.3 L [74% predicted] versus 2.5 L [78% predicted]) identified patients more likely to have a future exacerbation compared with patients who were not having an exacerbation. After correcting for FEV1, the asthma control questionnaire data were associated with exacerbations. In adolescents (ages ≥ 12 years) and adults with persistent mild asthma, most (73%) did not have sputum eosinophilia, and some of these patients responded well to the anticholinergic, tiotropium, which would argue differently from administration of an inhaled corticosteroid as first-line controller therapy. In a three-track study of patients with persistent mild asthma, as-needed budesonide-formoterol and scheduled budesonide were associated with approximately one-half of the annual exacerbation rate of as-needed albuterol. In patients with persistent moderate-to-severe asthma, tiotropium added to controller therapy caused an increase in FEV1 without improving the asthma control questionnaire findings. There were two studies that explored whether either quadrupling or quintupling the inhaled corticosteroid at the first sign of loss of control of asthma would provide meaningful reductions of severe exacerbations of asthma, but the findings did not support this strategy. Both biologic therapies and environmental control (dust mite impermeable encasings) have resulted in reductions of exacerbations in patients with persistent moderate and severe asthma.

Validation of a metered dose inhaler electronic monitoring device: implications for asthma clinical trial use

BackgroundThe SmartTouch Ventolin monitor (Adherium, Auckland, New Zealand) is an electronic monitor for use with a Ventolin metered dose inhaler, which records the date and time of inhaler actuations. This...

Three-month validation of a turbuhaler electronic monitoring device: implications for asthma clinical trial use

BackgroundElectronic monitoring of inhaled asthma therapy is suggested as the ‘gold standard’ for measuring patterns of medication use in clinical trials. The SmartTurbo (Adherium (NZ) Ltd, Auckland, New Zealand) is...

PARP inhibition by olaparib or gene knockout blocks asthma-like manifestation in mice by modulating CD4(+) T cell function.

BackgroundAn important portion of asthmatics do not respond to current therapies. Thus, the need for new therapeutic drugs is urgent. We have demonstrated a critical role for PARP in experimental asthma. Olaparib, a PARP inhibitor, was recently introduced in clinical trials against cancer. The objective of the present study was to examine the efficacy of olaparib in blocking established allergic airway inflammation and hyperresponsiveness similar to those observed in human asthma in animal models of the disease.MethodsWe used ovalbumin (OVA)-based mouse models of asthma and primary CD4+ T cells. C57BL/6J WT or PARP-1−/− mice were subjected to OVA sensitization followed by a single or multiple challenges to aerosolized OVA or left unchallenged. WT mice were administered, i.p., 1 mg/kg, 5 or 10 mg/kg of olaparib or saline 30 min after each OVA challenge.ResultsAdministration of olaparib in mice 30 min post-challenge promoted a robust reduction in airway eosinophilia, mucus production and hyperresponsiveness even after repeated challenges with ovalbumin. The protective effects of olaparib were linked to a suppression of Th2 cytokines eotaxin, IL-4, IL-5, IL-6, IL-13, and M-CSF, and ovalbumin-specific IgE with an increase in the Th1 cytokine IFN-γ. These traits were associated with a decrease in splenic CD4+ T cells and concomitant increase in T-regulatory cells. The aforementioned traits conferred by olaparib administration were consistent with those observed in OVA-challenged PARP-1−/− mice. Adoptive transfer of Th2-skewed OT-II-WT CD4+ T cells reversed the Th2 cytokines IL-4, IL-5, and IL-10, the chemokine GM-CSF, the Th1 cytokines IL-2 and IFN-γ, and ovalbumin-specific IgE production in ovalbumin-challenged PARP-1−/−mice suggesting a role for PARP-1 in CD4+ T but not B cells. In ex vivo studies, PARP inhibition by olaparib or PARP-1 gene knockout markedly reduced CD3/CD28-stimulated gata-3 and il4 expression in Th2-skewed CD4+ T cells while causing a moderate elevation in t-bet and ifn-γ expression in Th1-skewed CD4+ T cells.ConclusionsOur findings show the potential of PARP inhibition as a viable therapeutic strategy and olaparib as a likely candidate to be tested in human asthma clinical trials.

Proinflammatory Environmental Exposures in Asthma

Asthma is a chronic inflammatory disease that affects over 35 million people in the United States, and is a leading cause of hospitalization in children. While asthma‐causing allergens like fungi, mites, and insects represent biologically diverse organisms, they have some biological similarities that may underlie their potential to cause asthma. One of these shared biological features is the production of chitin. Studies have shown that chitin impacts lung function through the innate immune system. There are no available chitin assays for assessing environmental samples. Creation of a quantitative assay for chitin is complicated because it is a modified polysaccharide and not a protein. This makes it difficult to make antibodies that will specifically recognize it. Chitin is also poorly soluble in water and many standard solvents, which makes developing adequate standards challengingAfter successfully creating a chitin quantification assay with a detection limit of about 20ng/mg dust and validating commercially available assays for endotoxins and lipopolysaccharides, we acquired 387 household dust samples from the Inner‐City Anti‐IgE Therapy for Asthma (ICATA) clinical trial and quantified MAMPS like chitin, endotoxins and lipopolysaccharides in those samples. Quantifying chitin, endotoxins and glucans in household dust samples gave us a better understanding of the microbiome profile in those samples. Overall, this study contributes to our understanding of the mechanisms in human asthma and allergy. It also has the potential to improve existing techniques in the treatment and prevention of a disease that affects millions of people worldwide.

Using an electronic medical record (EMR) to conduct clinical trials: Salford Lung Study feasibility.

BackgroundReal-world data on the benefit/risk profile of medicines is needed, particularly in patients who are ineligible for randomised controlled trials conducted for registration purposes. This paper describes the methodology and source data verification which enables the conduct of pre-licensing clinical trials of COPD and asthma in the community using the electronic medical record (EMR), NorthWest EHealth linked database (NWEH-LDB) and alert systems.MethodsDual verification of extracts into NWEH-LDB was performed using two independent data sources (Salford Integrated Record [SIR] and Apollo database) from one primary care practice in Salford (N = 3504). A feasibility study was conducted to test the reliability of the NWEH-LDB to support longitudinal data analysis and pragmatic clinical trials in asthma and COPD. This involved a retrospective extraction of data from all registered practices in Salford to identify a cohort of patients with a diagnosis of asthma (aged ≥18) and/or COPD (aged ≥40) and ≥2 prescriptions for inhaled bronchodilators during 2008. Health care resource utilisation (HRU) outcomes during 2009 were assessed. Exacerbations were defined as: prescription for oral corticosteroids (OCS) in asthma and prescription of OCS or antibiotics in COPD; and/or hospitalisation for a respiratory cause.ResultsDual verification demonstrated consistency between SIR and Apollo data sources: 3453 (98.6%) patients were common to both systems; 99.9% of prescription records were matched and of 29,830 diagnosis records, one record was missing from Apollo and 272 (0.9%) from SIR. Identified COPD patients were also highly concordant (Kappa coefficient = 0.98).A total of 7981 asthma patients and 4478 COPD patients were identified within the NWEH-LDB. Cohort analyses enumerated the most commonly prescribed respiratory medication classes to be: inhaled corticosteroids (ICS) (42%) and ICS plus long-acting β2-agonist (LABA) (40%) in asthma; ICS plus LABA (55%) and long-acting muscarinic antagonists (36%) in COPD. During 2009 HRU was greater in the COPD versus asthma cohorts, and exacerbation rates in 2009 were higher in patients who had ≥2 exacerbations versus ≤1 exacerbation in 2008 for both asthma (137.5 vs. 20.3 per 100 person-years, respectively) and COPD (144.6 vs. 41.0, respectively).ConclusionApollo and SIR data extracts into NWEH-LDB showed a high level of concordance for asthma and COPD patients. Longitudinal data analysis characterized the COPD and asthma populations in Salford including medications prescribed and health care utilisation outcomes suitable for clinical trial planning.

Editorial introductions

Editorial introductions

More Effective Strategies are Needed for Elderly Asthmatics in Real-World Practice.

More Effective Strategies are Needed for Elderly Asthmatics in Real-World Practice.