Tiotropium improves lung function in patients with severe uncontrolled asthma: a randomized controlled trial

Clinical efficacy of tiotropium in children with asthma

OBJECTIVE

To investigate the clinical efficacy of tiotropium in children with asthma.

METHODS

Eighty children with newly diagnosed moderate persistent asthma were enrolled into this study. The children were randomly assigned to the fluticasone propionate aerosol group or the fluticasone propionate aerosol plus tiotropium group for 12 weeks.

RESULTS

Lung function was significantly improved in both groups at 4, 8, and 12 weeks compared with baseline (P < 0.01). Moreover, lung function was significantly improved in the tiotropium group compared with the control group (P < 0.05). However, there was no significant difference in the incidence of severe asthma between the two groups (36.3% and 26.8%, respectively; P > 0.05). Compared with the control group, the number of days and frequency of short-acting beta2-adrenoceptor agonist use was significantly reduced in the tiotropium group (P < 0.05). Awakenings during the night were also significantly decreased (P < 0.00). There were no severe adverse reactions in either of the study groups.

CONCLUSION

Tiotropium could significantly improve lung function, reduce the use of short-acting beta2-adrenoceptor agonists, and improve sleep in children with asthma. Furthermore, few adverse reactions were reported.

Health-related quality of life measurement in asthma and chronic obstructive pulmonary disease: review of the 2009-2014 literature

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) are frequent in the general population. These diseases can worsen the quality of life of people suffering from them, limiting their daily activities and disrupting their sleep at night. Some questionnaires to measure the impact of the diseases on the daily life of patients are available. The measurements of subjective outcomes have become a part of clinical practice, and are used very frequently in clinical trials. Our aim was to describe how data on HRQoL in asthma and COPD are reported in papers published in the medical literature.

METHODS

We identified papers on the recent respiratory drugs (chemical, not biological), that reported the HRQoL measurement and that were published from 2009 to April 2014. We planned to describe data about HRQoL, and we had no intention of comparing the degree of efficacy of drugs.

RESULTS

The most used questionnaires are the Asthma Quality of Life Questionnaire (AQLQ) and the Saint George's Respiratory Questionnaire (SGRQ). These tools, administered at the baseline and at the end of the study (and interim evaluations in the longer studies) allowed for the identification of improvements as perceived by the patient after the treatment, even if in some cases these improvements were limited and not clinically relevant. Subjective measurements have always been placed among the secondary endpoints and the number of patients (estimated for the main endpoint) has often statistically overestimated the result. In addition, it is clear that subjective data is normally reported, but rarely commented on.

CONCLUSIONS

There are some methodology aspects that should be discussed in more depth, for example the necessity to express variations in the subjective perception, not as p-value but as effect-size.

Novel strategies for the treatment of asthma

Novel treatment strategies are currently emerging for patients with inadequately controlled asthma despite good adherence and trigger avoidance. These strategies serve primarily to reduce or completely avoid long-term oral corticosteroid therapy. A number of these options have already been implemented in practice or will soon be authorized for the treatment of asthma, while others still need to prove their clinical practicability, safety and efficacy. The present article provides an overview of the broad spectrum of novel inhaled, oral, systemic, and invasive treatment strategies for asthma.

Pharmacotherapy in the management of asthma in the elderly: a review of clinical studies

Asthma in the elderly is a disease with emerging concern. Despite some recent advances in our understanding of epidemiology and pathophysiology, there is a considerable lack of clinical evidence specific to elderly patients. Currently available high quality clinical evidence has been mostly obtained from younger adults, but rarely from elderly patients. Under-representation of elderly patients in previous randomized trials may have been due to being, old age, or having comorbidities. Thus, a question may be raised whether current clinical evidence could be well generalized into elderly patients. Further clinical trials should address clinical issues raised in elderly population. In this review, we aimed to overview the efficacy and safety of pharmacological management, and also to summarize the literature relevant to elderly asthma.

Tiotropium Respimat®: A Review of Its Use in Asthma Poorly Controlled with Inhaled Corticosteroids and Long-Acting β2-Adrenergic Agonists

Tiotropium bromide (Spiriva®) solution for inhalation via the Respimat® Soft Mist™ inhaler is a long-acting anticholinergic agent approved in the EU for the add-on maintenance treatment of asthma in adults currently receiving maintenance therapy with an inhaled corticosteroid (ICS) (≥800 µg budesonide per day or equivalent) and a long-acting β2-adrenergic agonist (LABA) and who have experienced at least one severe exacerbation in the previous year. Tiotropium Respimat® added to maintenance ICS/LABA treatment significantly improved lung function after 6 months' treatment and extended the time to the first asthma exacerbation in two well-designed, replicate, phase III trials in patients with poorly controlled asthma despite treatment with an ICS (≥800 µg budesonide/day or equivalent) and a LABA. Tiotropium Respimat® was also associated with a reduced incidence of severe asthma exacerbations and an increase in the median time to asthma worsening. The drug was well tolerated in asthma patients throughout 48 weeks' treatment, with a generally similar incidence of serious adverse events in tiotropium Respimat® and placebo treatment groups. Thus, in patients with poorly controlled asthma despite receiving high-dose ICS and a LABA, tiotropium Respimat® provides a valuable treatment option.

Long-acting muscarinic antagonists (LAMA) added to combination long-acting beta2-agonists and inhaled corticosteroids (LABA/ICS) versus LABA/ICS for adults with asthma

BACKGROUND

Maintenance treatment with long-acting beta2-agonists and inhaled corticosteroids (LABA/ICS) can relieve asthma symptoms and reduce the frequency of exacerbations, but there are limited treatment options for people who do not gain control on combination LABA/ICS. Long-acting muscarinic antagonists (LAMA) are a class of inhaled drug which have been effective for people with chronic obstructive pulmonary disease and are now becoming available for people with asthma to take alongside their LABA/ICS inhaler.

OBJECTIVES

To assess the effects of adding a long-acting muscarinic antagonist (LAMA) to combination long-acting beta2-agonists (LABA) and inhaled corticosteroids (ICS) in adults whose asthma is not well controlled by LABA/ICS.

SEARCH METHODS

We identified trials from the Cochrane Airways Review Group Specialised Register (CAGR) up to January 2016. We also searched ClinicalTrials.gov, the WHO trials portal, and reference lists of other reviews, and we contacted trial authors for additional information.

SELECTION CRITERIA

We included parallel randomised controlled trials (RCTs) of at least 12 weeks' duration. Studies met the inclusion criteria if they compared LAMA as an add-on to LABA/ICS versus LABA/ICS alone for adults with asthma. We included studies reported as full text, those published as abstract only, and unpublished data. Primary outcomes were exacerbations requiring oral corticosteroids (OCS), validated measures of asthma control, and serious adverse events (including mortality).

DATA COLLECTION AND ANALYSIS

Two review authors screened searches and independently extracted details on risk of bias and numerical data. We analysed dichotomous data as odds ratios (ORs) and continuous data as mean differences (MD) using a random-effects model. We rated all outcomes using GRADE.

MAIN RESULTS

We found four double-blind, double-dummy trials comparing LAMA to placebo, including 1197 people with asthma taking combination LABA/ICS. One of the trials was designed to study glycopyrronium bromide but was withdrawn prior to enrolment, and the other three all studied tiotropium bromide (mostly 5 µg once daily via Respimat) over 48 to 52 weeks. People in the trials had a mean forced expiratory volume in one second (FEV1) of 55% of their predicted value, indicating severe asthma.People randomised to take tiotropium add-on had fewer exacerbations requiring oral corticosteroids than those continuing to take LABA/ICS alone, but the confidence intervals did not rule out no difference (OR 0.76, 95% CI 0.57 to 1.02; moderate quality evidence). Over 48 weeks, 328 out of 1000 people taking their usual LABA/ICS would have to take oral corticosteroids for an exacerbation compared with 271 if they took tiotropium as well (95% CI 218 to 333 per 1000). Analyses comparing the number of exacerbations per patient in each group (rate ratio) and the time until first exacerbation (hazard ratio) were in keeping with the main result. Quality of life, as measured by the Asthma Quality of Life Questionnaire (AQLQ) was no better for those taking tiotropium add-on than for those taking LABA/ICS alone when considered in light of the 0.5 minimal clinically important difference on the scale (MD 0.09, 95% CI - 0.03 to 0.20), and evidence for whether tiotropium increased or decreased serious adverse events in this population was inconsistent (OR 0.60, 95% CI 0.24 to 1.47; I(2) = 76%).Within the secondary outcomes, exacerbations requiring hospital admission were too rare to tell whether tiotropium was beneficial over LABA/ICS alone. There was high quality evidence showing benefits to lung function (trough FEV1 and forced vital capacity (FVC)) and potentially small benefits to asthma control. People taking tiotropium add-on were less likely to experience non-serious adverse events.

AUTHORS' CONCLUSIONS

Tiotropium add-on may have additional benefits over LABA/ICS alone in reducing the need for rescue oral steroids in people with severe asthma. The effect was imprecise, and there was no evidence for other LAMA preparations. Possible benefits on quality of life were negligible, and evidence for the effect on serious adverse events was inconsistent. There are likely to be small added benefits for tiotropium Respimat 5 µg daily on lung function and asthma control over LABA/ICS alone and fewer non-serious adverse events. The benefit of tiotropium add-on on the frequency of hospital admission is still unknown, despite year-long trials.Ongoing and future trials should clearly describe participants' background medications to help clinicians judge how the findings relate to stepwise care. If studies test LAMAs other than tiotropium Respimat for asthma, they should be at least six months long and use accepted and validated outcomes to allow comparisons of the safety and effectiveness between different preparations.

World Workshop on Oral Medicine VI: a systematic review of medication-induced salivary gland dysfunction

The aim of this paper was to perform a systematic review of the pathogenesis of medication-induced salivary gland dysfunction (MISGD). Review of the identified papers was based on the standards regarding the methodology for systematic reviews set forth by the World Workshop on Oral Medicine IV and the PRISMA statement. Eligible papers were assessed for both the degree and strength of relevance to the pathogenesis of MISGD as well as on the appropriateness of the study design and sample size. A total of 99 papers were retained for the final analysis. MISGD in human studies was generally reported as xerostomia (the sensation of oral dryness) without measurements of salivary secretion rate. Medications may act on the central nervous system (CNS) and/or at the neuroglandular junction on muscarinic, α-and β-adrenergic receptors and certain peptidergic receptors. The types of medications that were most commonly implicated for inducing salivary gland dysfunction were those acting on the nervous, cardiovascular, genitourinary, musculoskeletal, respiratory, and alimentary systems. Although many medications may affect the salivary flow rate and composition, most of the studies considered only xerostomia. Thus, further human studies are necessary to improve our understanding of the association between MISGD and the underlying pathophysiology.

The Saudi Initiative for Asthma - 2016 update: Guidelines for the diagnosis and management of asthma in adults and children

This is an updated guideline for the diagnosis and management of asthma, developed by the Saudi Initiative for Asthma (SINA) group, a subsidiary of the Saudi Thoracic Society. The main objective of SINA is to have guidelines that are up to date, simple to understand and easy to use by nonasthma specialists, including primary care and general practice physicians. SINA approach is mainly based on symptom control and assessment of risk as it is the ultimate goal of treatment. The new SINA guidelines include updates of acute and chronic asthma management, with more emphasis on the use of asthma control in the management of asthma in adults and children, inclusion of a new medication appendix, and keeping consistency on the management at different age groups. The section on asthma in children is rewritten and expanded where the approach is stratified based on the age. The guidelines are constructed based on the available evidence, local literature, and the current situation in Saudi Arabia. There is also an emphasis on patient-doctor partnership in the management that also includes a self-management plan.

Clinical asthma phenotypes in the real world: opportunities and challenges

Asthma is a common, chronic and heterogeneous syndrome, affecting people of all ages, all races and both sexes. It may range from mild disease with barely noticeable symptoms, to very severe disease with constant symptoms that greatly hinder the life of the patient. Guidelines issued by various medical societies provide guidance on how to diagnose and manage asthmatic patients. It is now increasingly recognised that asthma management must be individualised, tailored not only to the severity of the disease but to the phenotypic characteristics of each patient. The aim of asthma treatment is control of asthma and the prevention of risk of exacerbations and fixed airflow limitation. Asthma control can be easily assessed clinically through simple screening tools such as the use of validated questionnaires and spirometry. The use of inflammatory biomarkers can be an alternative approach that, however, requires more time and resources. Asthma treatment involves the use of controllers, mainly inhaled corticosteroids and long-acting β2-agonists, and relievers, mainly rapid-acting β2-agonists. Controller medications reduce airway inflammation, lead to better symptom control and reduce the risk of future exacerbations. Reliever (rescue) medications alleviate symptoms and prevent exercise-induced bronchoconstriction. Treatment must be based on a "stepwise approach" in order to achieve good control of symptoms and to minimise future risks of exacerbations. That is, less treatment for mild disease, more treatment for severe, uncontrolled disease. Once good asthma control has been achieved and maintained, treatment should be stepped down. In severe asthmatics, phenotypic characterisation becomes more clinically useful and add-on treatment such as anti-immunoglobulin E monoclonal antibodies may be required. Despite our better understanding of asthma, there are still patients who will not respond to treatment and remain symptomatic. Dissemination of guidelines and national plans allowing early diagnosis of asthma as well as access to specialised primary and secondary care for asthmatic patients, personalised treatment and continuity of care may lead to excellence in care and controlled asthma for the majority of patients. Education of the patient in asthma is also very important, as in every chronic disease, as the patients live with the disease every day while they visit a healthcare professional a few times a year. Future planning for new treatments should focus on the needs of such severe asthma patients.

Interaction between corticosteroids and muscarinic antagonists in human airways

BACKGROUND

To date there is emerging clinical evidence to add long-acting anti-muscarinic agents (LAMAs) with inhaled corticosteroid (ICSs) in asthma, but the pharmacological rationale that supports the use of such a combination has not yet been explained. The aim of this study was to pharmacologically investigate the interaction between the ICS beclomethasone and the LAMA glycopyrronium on the human airway smooth muscle (ASM) tone.

METHODS

We investigated the rapid non-genomic bronchorelaxant effect of beclomethasone and glycopyrronium, administered alone and in combination, in human isolated bronchi and bronchioles. Experiments were carried out also in passively sensitized airways and the pharmacological analysis of drug interaction was performed by Bliss Independence method.

RESULTS

The acute administration of beclomethasone and glycopyrronium induced a significant relaxation of passively sensitized ASM pre-contracted with histamine, by causing submaximal/maximal inhibition of the contractile tone in both medium bronchi and bronchioles. Beclomethasone was characterized by a rapid non-genomic and epithelium independent bronchorelaxant effect. In passively sensitized airways, this effect seemed to be dependent by the activation of a Gsα--cyclic adenosine monophosphate (cAMP)--protein kinase A cascade. While no synergistic interaction was detected in non-sensitized bronchi, the beclomethasone/glycopyrronium combination synergistically enhanced the relaxation of passively sensitized medium and small bronchi. The synergistic interaction between beclomethasone and glycopyrronium was associated with an increase of cAMP concentrations.

CONCLUSIONS

Our study provides for the first time the pharmacological rationale for combining low doses of an ICS plus a LAMA.

Therapeutic approaches to asthma-chronic obstructive pulmonary disease overlap syndromes

The recognition that there are some patients with features of asthma and chronic obstructive pulmonary disease (COPD) has highlighted the need to develop more specific treatments for these clinical phenotypes. Some patients with COPD have predominantly eosinophilic inflammation and might respond to high doses of inhaled corticosteroids and newly developed specific antieosinophil therapies, including blocking antibodies against IL-5, IL-13, IL-33, and thymic stromal lymphopoietin, as well as oral chemoattractant receptor-homologous molecule expressed on TH2 cells antagonists. Other patients have severe asthma or are asthmatic patients who smoke with features of COPD-induced inflammation and might benefit from treatments targeting neutrophils, including macrolides, CXCR2 antagonists, phosphodiesterase 4 inhibitors, p38 mitogen-activating protein kinase inhibitors, and antibodies against IL-1 and IL-17. Other patients appear to have largely fixed obstruction with little inflammation and might respond to long-acting bronchodilators, including long-acting muscarinic antagonists, to reduce hyperinflation. Highly selected patients with severe asthma might benefit from bronchial thermoplasty. Some patients with overlap syndromes can be conveniently treated with triple fixed-dose combination inhaler therapy with an inhaled corticosteroid, long-acting β2-agonist, and long-acting muscarinic antagonist, several of which are now in development. Corticosteroid resistance is a feature of asthma-COPD overlap syndrome, and understanding the various molecular mechanisms of this resistance has identified novel therapeutic targets and presented the prospect of therapies that can restore corticosteroid responsiveness.

The Effect of Tiotropium in Symptomatic Asthma Despite Low- to Medium-Dose Inhaled Corticosteroids: A Randomized Controlled Trial

BACKGROUND

Tiotropium, a once-daily long-acting anticholinergic bronchodilator, has demonstrated efficacy in patients with asthma who were symptomatic despite treatment with medium- to high-dose inhaled corticosteroids (ICS).

OBJECTIVE

The objective of this study was to evaluate the efficacy and safety of once-daily tiotropium Respimat (5 μg or 2.5 μg), compared with placebo Respimat, as add-on therapy to low- to medium-dose ICS for adults with symptomatic asthma.

METHODS

A phase III, double-blind, placebo-controlled trial was conducted (NCT01316380). Adults with symptomatic asthma receiving low- to medium-dose ICS (200-400 μg budesonide or equivalent dose) and a pre-bronchodilator forced expiratory volume in 1 second (FEV1) ≥60% and ≤90% of predicted normal were randomized to 12 weeks of treatment with once-daily tiotropium Respimat 5 μg or 2.5 μg, or placebo Respimat, as add-on therapy to ICS. The primary endpoint was peak FEV1(0-3h) response.

RESULTS

In total, 464 patients were randomized (61% female; mean age 43 years; mean baseline FEV1 78% of predicted normal). After 12 weeks, both tiotropium Respimat doses were superior to placebo (adjusted mean difference from placebo: 5 μg, 128 mL; 2.5 μg, 159 mL; both P < .001). Both doses of tiotropium Respimat were also superior to placebo with regard to the secondary endpoints of adjusted mean trough FEV1 and FEV1 area under the curve(0-3h) responses, and the other endpoints of morning and evening peak expiratory flow. Adverse events were comparable across the treatment groups.

CONCLUSIONS

Once-daily tiotropium Respimat add-on therapy to low- to medium-dose ICS in adults with symptomatic asthma is an efficacious bronchodilator, and its safety and tolerability are comparable with those of placebo Respimat.

Tiotropium bromide as add-on therapy to inhaled corticosteroids for treating asthma

INTRODUCTION

Bronchial asthma is becoming increasingly prevalent worldwide. Although first-line therapy with inhaled corticosteroids (ICS) with or without long-acting β2 agonists (LABA) has significantly improved the clinical outcomes of asthma, they cannot provide all asthmatics with good control and thus alternatives or add-on drugs are required. Tiotropium is a long-acting muscarinic antagonist that has been used to treat chronic obstructive pulmonary disease and it has been approved for treating asthma in some countries. This agent has similar bronchodilatory effects to those of LABA and might also have anti-inflammatory and anti-remodeling effects.

AREAS COVERED

Some pivotal clinical trials have found tiotropium effective as an add-on medication for low-to-medium doses of ICS for treating symptomatic asthma and asthma that remains uncontrolled despite ICS plus LABA therapy.

EXPERT OPINION

Whether or not tiotropium has anti-inflammatory and anti-remodeling effects in humans with asthma is an important issue. Predictors that would identify patients who would derive the maximal potential benefit from treatment with tiotropium in addition to their current therapy are also needed. Although the cardiovascular toxicity of tiotropium is less remarkable in asthma than in chronic obstructive pulmonary disease, longer and larger studies are still needed to confirm the safety of tiotropium for treating asthma.

Severe asthma in school-age children: evaluation and phenotypic advances

Although the majority of children with asthma have a favorable clinical response to treatment with low to moderate doses of inhaled corticosteroids (ICS), a small subset of children have "severe" asthma characterized by ongoing symptoms and airway inflammation despite treatment with high doses of ICS and even oral corticosteroids. Although there is symptom heterogeneity in the affected children, children with severe asthma share the risk for adverse outcomes, including recurrent and potentially life-threatening exacerbations, which contribute to substantial economic burden. This article reviews current knowledge of severe asthma in school-age children (age 6-17 years) with a focus on recent literature published after January 2012. Clinical management approaches for children with severe asthma are discussed as well as current phenotyping efforts and emerging phenotypic-directed therapies that may be of benefit for subpopulations of children with severe asthma in the future.

Severe asthma: definition, diagnosis and treatment

BACKGROUND

A minority of patients with asthma have uncontrolled or partially controlled asthma despite intensive treatment. These patients present a special challenge because of the extensive diagnostic evaluation that they need, insufficient evidence regarding personalized treatments, and their high consumption of health-care resources.

METHODS

The definition, diagnosis, and treatment of severe asthma are presented on the basis of a selective literature review and the authors' clinical experience.

RESULTS

Severe asthma is present, by definition, when adequate control of asthma cannot be achieved by high-dose treatment with inhaled cortico - steroids and additional controllers (long-acting inhaled beta 2 agonists, montelukast, and/or theophylline) or by oral corticosteroid treatment (for at least six months per year), or is lost when the treatment is reduced. Before any further treatments are evaluated, differential diagnoses of asthma should be ruled out, comorbidities should be treated, persistent triggers should be eliminated, and patient adherence should be optimized. Moreover, pulmonary rehabilitation is recommended in order to stabilize asthma over the long term and reduce absences from school or work. The additional drugs that can be used include tiotropium, omalizumab (for IgE-mediated asthma), and azithromycin (for non-eosinophilic asthma). Antibodies against interleukin-5 or its receptor will probably be approved soon for the treatment of severe eosinophilic asthma.

CONCLUSION

The diagnosis and treatment of severe asthma is time consuming and requires special experience. There is a need for competent treatment centers, continuing medical education, and research on the prevalence of severe asthma.

New and future strategies to improve asthma control in children

Symptomatic asthma in childhood has lifelong effects on lung function and disease severity, emphasizing the need for improved pediatric asthma control. Control of pediatric risk and impairment domains can be achieved through increased medication adherence or new therapeutic strategies. Developing electronic monitoring device technology with reminders might be a key noninvasive resource to address poor adherence in children and adolescents in a clinical setting. In patients who have persistently poor control despite optimal medication compliance, newly emerging pharmaceuticals, including inhaled therapies and biologics, might be key to their treatment. However, barriers exist to their development in the pediatric population, and insights must be drawn from adult studies, which has its own unique limitations. Biomarkers to direct the use of such potentially expensive therapies to those patients most likely to benefit are imperative. In this review the current literature regarding strategies to improve pediatric asthma control is addressed with the goal of exploring the potential and pitfalls of strategies that might be available in the near future.

Emerging therapeutic options for the treatment of patients with symptomatic asthma

OBJECTIVE

Asthma is a chronic inflammatory disorder of the airways with increasing worldwide prevalence. Despite treatment according to guidelines, a considerable proportion of patients with asthma remain symptomatic. Different potential therapeutic options for the treatment of these patients are currently in development and undergoing clinical trials, and it is important to regularly review their status.

DATA SOURCES

A search of ClinicalTrials.gov was performed and supported by a PubMed literature search and restricted to the previous 10 years to ensure currency of data. The results were manually filtered to identify relevant articles.

STUDY SELECTIONS

Emerging therapies that are currently in phase 2 and 3 development include anti-interleukin agents (benralizumab, reslizumab, dupilumab, brodalumab, lebrikizumab, and mepolizumab), a chemoattractant receptor-homologous molecule expressed on a T-helper type 2 lymphocyte antagonist (OC000459), a phosphodiesterase-4 inhibitor (roflumilast), and long-acting muscarinic antagonists (glycopyrronium bromide, umeclidinium bromide, and tiotropium bromide).

RESULTS

The clinical trial program of the long-acting muscarinic antagonist tiotropium is currently the most advanced, with data available from different phase 2 and 3 studies. Results demonstrate that it is an efficacious add-on to at least inhaled corticosteroid maintenance therapy across severities of symptomatic asthma.

CONCLUSION

The results of ongoing and future studies will help to determine whether these emerging therapeutic options will help address the unmet need for improvement in asthma management.

Managing severe asthma in adults: lessons from the ERS/ATS guidelines

PURPOSE OF REVIEW

To review the latest guidelines on severe asthma.

RECENT FINDINGS

An updated definition of severe asthma is provided together with the evaluation steps necessary to reach a diagnosis of severe asthma. The importance of phenotyping is emphasized, and recommendations are provided for therapies specifically directed for severe asthma.

SUMMARY

Severe asthma is widely recognized as a major unmet need. It is defined as asthma that requires treatment with high-dose inhaled corticosteroids and a second controller and/or systemic corticosteroid to prevent it from becoming 'uncontrolled' or that remains 'uncontrolled' despite this therapy. Severe asthma is a heterogeneous condition that consists of phenotypes such as eosinophilic asthma. More phenotypes need to be defined. Evaluation of the patient referred to as having severe or difficult-to-control asthma must take into account adherence to treatment, comorbidities and associated factors including side effects from therapies. These need to be addressed. Recommendations on the use of sputum eosinophil count and exhaled nitric oxide to guide therapy are presented. Treatment with anti-IgE antibody, methotrexate, macrolide antibiotics, antifungal agents and bronchial thermoplasty is reviewed and recommendations made. Research efforts into phenotyping of severe asthma will provide both biomarker-driven approaches and newer effective therapies to severe asthma management.

Role of anticholinergics in asthma management: recent evidence and future needs

PURPOSE OF REVIEW

Anticholinergic antimuscarinic bronchodilators play a major role in the treatment of chronic obstructive pulmonary disease, but their role in asthma has long been limited to acute management. More recently, the role of long-acting antimuscarinic bronchodilators (LAMAs) in chronic asthma management has been explored. This review will examine the pharmacological rationale for use of inhaled anticholinergics in the treatment of asthma, and provide an overview of the current literature supporting this use, as well as describe future research needs in this area.

RECENT FINDINGS

Short-acting anticholinergic bronchodilators have a role as add-on agents in the treatment of acute asthma. Preliminary clinical studies suggest that inhaled LAMAs may be comparable to long-acting beta2-agonists (LABAs) as an add-on therapy in patients not controlled by inhaled corticosteroids (ICS) alone, and may also have added benefit in patients not controlled on combined ICS-LABA. Mechanistic studies suggest that apart from their bronchodilator activity, LAMAs may have anti-inflammatory and antiremodeling influences on the airways. Further research is needed to clarify the clinical relevance of these experimental observations.

SUMMARY

Accumulating evidence supports the use of inhaled LAMAs as an add-on therapy in patients with asthma, who remain symptomatic despite guideline-based therapy with ICS with or without LABAs. Further studies are warranted to help define mechanisms of action of LAMAs, apart from their role as bronchodilators, and determine how these other actions impact asthma outcomes over time. Furthermore, future studies need to examine the long-term efficacy and safety of LAMAs in asthma and identify a subgroup of patients who would benefit from such therapies to facilitate early, personalized therapy.

Asthma therapy and its effect on airway remodelling

Asthma remains a major health problem with significant morbidity, mortality and economic costs. In asthma, airway remodelling, which refers to all the microscopic structural changes seen in the airway tissue, has been recognised for many decades and remains one of the defining characteristics of the disease; however, it is still poorly understood. The detrimental pathophysiological consequences of some features of remodelling, like increased airway smooth muscle mass and subepithelial fibrosis, are well documented. However, whether targeting these by therapy would be beneficial is unknown. Although the prevailing thinking is that remodelling is an abnormal response to persistent airway inflammation, recent evidence, especially from studies of remodelling in asthmatic children, suggests that the two processes occur in parallel. The effects of asthma therapy on airway remodelling have not been studied extensively due to the challenges of obtaining airway tissue in the context of clinical trials. Corticosteroids remain the cornerstone of asthma therapy, and their effects on remodelling have been better studied than other drugs. Bronchial thermoplasty is the only asthma therapy to primarily target remodelling, although how it results in the apparent clinical benefits seen is not exactly clear. In this article we discuss the mechanisms of airway remodelling in asthma and review the effects of conventional and novel asthma therapies on the process.

Tiotropium attenuates IL-13-induced goblet cell metaplasia of human airway epithelial cells

BACKGROUND

It has been shown that acetylcholine is both a neurotransmitter and acts as a local mediator, produced by airway cells including epithelial cells. In vivo studies have demonstrated an indirect role for acetylcholine in epithelial cell differentiation. Here, we aimed to investigate direct effects of endogenous non-neuronal acetylcholine on epithelial cell differentiation.

METHODS

Human airway epithelial cells from healthy donors were cultured at an air-liquid interface (ALI). Cells were exposed to the muscarinic antagonist tiotropium (10 nM), interleukin (IL)-13 (1, 2 and 5 ng/mL), or a combination of IL-13 and tiotropium, during or after differentiation at the ALI.

RESULTS

Human airway epithelial cells expressed all components of the non-neuronal cholinergic system, suggesting acetylcholine production. Tiotropium had no effects on epithelial cell differentiation after air exposure. Differentiation into goblet cells was barely induced after air exposure. Therefore, IL-13 (1 ng/mL) was used to induce goblet cell metaplasia. IL-13 induced MUC5AC-positive cells (5-fold) and goblet cells (14-fold), as assessed by histochemistry, and MUC5AC gene expression (105-fold). These effects were partly prevented by tiotropium (47-92%). Goblet cell metaplasia was induced by IL-13 in a dose-dependent manner, which was inhibited by tiotropium. In addition, tiotropium reversed goblet cell metaplasia induced by 2 weeks of IL-13 exposure. IL-13 decreased forkhead box protein A2 (FoxA2) expression (1.6-fold) and increased FoxA3 (3.6-fold) and SAM-pointed domain-containing ETS transcription factor (SPDEF) (5.2-fold) expression. Tiotropium prevented the effects on FoxA2 and FoxA3, but not on SPDEF.

CONCLUSIONS

We demonstrate that tiotropium has no effects on epithelial cell differentiation after air exposure, but inhibits and reverses IL-13-induced goblet cell metaplasia, possibly via FoxA2 and FoxA3. This indicates that non-neuronal acetylcholine contributes to goblet cell differentiation by a direct effect on epithelial cells.

Severe asthma in children

Severe asthma in children is characterized by sustained symptoms despite treatment with high doses of inhaled corticosteroids or oral corticosteroids. Children with severe asthma may fall into 2 categories, difficult-to-treat asthma or severe therapy-resistant asthma. Difficult-to-treat asthma is defined as poor control due to an incorrect diagnosis or comorbidities, or poor adherence due to adverse psychological or environmental factors. In contrast, treatment resistant is defined as difficult asthma despite management of these factors. It is increasingly recognized that severe asthma is a highly heterogeneous disorder associated with a number of clinical and inflammatory phenotypes that have been described in children with severe asthma. Guideline-based drug therapy of severe childhood asthma is based primarily on extrapolated data from adult studies. The recommendation is that children with severe asthma be treated with higher-dose inhaled or oral corticosteroids combined with long-acting β-agonists and other add-on therapies, such as antileukotrienes and methylxanthines. It is important to identify and address the influences that make asthma difficult to control, including reviewing the diagnosis and removing causal or aggravating factors. Better definition of the phenotypes and better targeting of therapy based upon individual patient phenotypes is likely to improve asthma treatment in the future.

What is the role of tiotropium in asthma?: a systematic review with meta-analysis

BACKGROUND

The role of tiotropium for the treatment of asthma has not yet been clearly defined. The aim of this systematic review was to assess the efficacy and safety of tiotropium in patients with asthma.

METHODS

Randomized placebo-controlled trials were included. Primary outcomes were peak and trough FEV1 and morning and evening peak expiratory flow (PEF).

RESULTS

Thirteen studies (4,966 patients) were included. Three different therapeutic protocols were identified. Tiotropium as an add-on to inhaled corticosteroids (ICSs) showed statistically and clinically significant increases in PEF (22-24 L/min) and FEV1 (140-150 mL). Additionally, tiotropium decreased the rate of exacerbations (number needed to treat for benefit [NNTB], 36) and improved asthma control. The use of tiotropium in patients poorly controlled despite the use of medium to high doses of ICS was not inferior to salmeterol. Finally, the use of tiotropium as an add-on to ICS/salmeterol combination increased pulmonary function to a clinically significant magnitude, reduced asthma exacerbations (relative risk, 0.70; 95% CI, 0.53-0.94; P < .02; I2 = 0%; NNTB, 17), and improved asthma control compared with ICS/salmeterol. Tiotropium was well tolerated, and no potential safety signals were observed.

CONCLUSIONS

Tiotropium resulted noninferiorly to salmeterol and superiorly to placebo in patients with moderate to severe asthma who were not adequately controlled by ICS or ICS/salmeterol. Major benefits were concentrated in the increase in lung function and in the case of patients with severe asthma, in the reduction of exacerbations.

Long-Term Once-Daily Tiotropium Respimat® Is Well Tolerated and Maintains Efficacy over 52 Weeks in Patients with Symptomatic Asthma in Japan: A Randomised, Placebo-Controlled Study

Background

This study assessed the long-term safety and efficacy of tiotropium Respimat, a long-acting inhaled anticholinergic bronchodilator, in asthma, added on to inhaled corticosteroids (ICS) with or without long-acting β₂-agonist (LABA).

Methods

285 patients with symptomatic asthma, despite treatment with ICS±LABA, were randomised 2:2:1 to once-daily tiotropium 5 μg, tiotropium 2.5 μg or placebo for 52 weeks (via the Respimat SoftMist inhaler) added on to ICS±LABA, in a double-blind, placebo-controlled, parallel-group study (NCT01340209). Primary objective: to describe the long-term safety profile of tiotropium. Secondary end points included: trough forced expiratory volume in 1 second (FEV₁) response; peak expiratory flow rate (PEFR) response; seven-question Asthma Control Questionnaire (ACQ-7) score.

Results

At Week 52, adverse-event (AE) rates with tiotropium 5 μg, 2.5 μg and placebo were 88.6%, 86.8% and 89.5%, respectively. Commonly reported AEs with tiotropium 5 μg, 2.5 μg and placebo were nasopharyngitis (48.2%, 44.7%, 42.1%), asthma (28.9%, 29.8%, 38.6%), decreased PEFR (15.8%, 7.9%, 21.1%), bronchitis (9.6%, 13.2%, 7.0%), pharyngitis (7.9%, 13.2%, 3.5%) and gastroenteritis (10.5%, 3.5%, 5.3%). In the tiotropium 5 μg, 2.5 μg and placebo groups, 8.8%, 5.3% and 5.3% of patients reported drug-related AEs; 3.5%, 3.5% and 15.8% reported serious AEs. Asthma worsening was the only serious AE reported in more than one patient. At Week 52, adjusted mean trough FEV₁ and trough PEFR responses were significantly higher with tiotropium 5 μg (but not 2.5 μg) versus placebo. ACQ-7 responder rates were higher with tiotropium 5 μg and 2.5 μg versus placebo at Week 24.

Conclusions

The long-term tiotropium Respimat safety profile was comparable with that of placebo Respimat, and associated with mild to moderate, non-serious AEs in patients with symptomatic asthma despite ICS±LABA therapy. Compared with placebo, tiotropium 5 μg, but not 2.5 μg, significantly improved lung function and symptoms, supporting the long-term efficacy of the 5 μg dose.

Trial Registration

ClinicalTrials.gov NCT01340209

The impact of asthma exacerbations and preventive strategies

OBJECTIVE

To review the pathophysiologic mechanisms underlying asthma exacerbations, the impact of exacerbations, and both current and future treatment strategies to establish asthma control and reduce the risk of future exacerbations.

RESEARCH DESIGN AND METHODS

Relevant adult data were identified via PubMed, with additional references obtained by reviewing bibliographies from selected articles.

RESULTS

Asthma exacerbations or 'attacks' are acute episodes of progressive worsening of symptoms which occur in patients with all degrees of asthma severity and are an important cause of morbidity and mortality. For patients, these asthma attacks constitute a considerable part of the disease burden in terms of both personal suffering and economic impact. Exacerbations are characterized in part by decreases in expiratory flow or lung function. The pathophysiologic mechanism underlying these changes is likely to be different depending on the specific asthma phenotype. Asthma exacerbations are commonly initiated by upper respiratory tract infections and/or environmental allergens, although there are other known factors which increase the risk of a patient developing exacerbations, such as cigarette smoking. Establishing asthma control and reducing the risk of future exacerbations is the main goal of asthma treatment. Inhaled corticosteroids alone or in combination with long-acting β2-agonists, in addition to other step-up strategies such as leukotriene receptor antagonists and theophylline, are recommended. The anti-immunoglobulin E monoclonal antibody omalizumab should also be considered in difficult-to-treat allergic asthma.

CONCLUSIONS

Despite the currently available treatments, many patients with asthma remain symptomatic and experience exacerbations regardless of disease severity. New therapies, including long-acting anticholinergics, anti-cytokines, and chemoattractant receptor-homologous molecules, are under investigation with some promising results. In addition to increased education and use of self-management plans, these novel therapies are essential to help improve asthma control and reduce exacerbation risk.

A randomised dose-ranging study of tiotropium Respimat® in children with symptomatic asthma despite inhaled corticosteroids

BACKGROUND

A considerable number of children with asthma remain symptomatic despite treatment with inhaled corticosteroids, resulting in significant morbidity, reduced quality of life, increased healthcare costs and lost school days. The aim of our study was to assess the efficacy, safety and tolerability of once-daily tiotropium Respimat® 5 μg, 2.5 μg and 1.25 μg add-on to medium-dose inhaled corticosteroids, with or without a leukotriene modifier, in children aged 6-11 years with symptomatic asthma.

METHODS

In this Phase II, double-blind, placebo-controlled, incomplete-crossover, dose-ranging study, patients were randomised to receive three of the four treatments evaluated: once-daily tiotropium Respimat® 5 μg, 2.5 μg or 1.25 μg or placebo Respimat®, in the evening during the 12-week (three × 4-week) treatment period.

RESULTS

In total, 76, 74, 75 and 76 patients aged 6-11 years received tiotropium Respimat® 5 μg, 2.5 μg, 1.25 μg and placebo Respimat®, respectively. For the primary end point (peak forced expiratory volume in 1 second measured within 3 hours post-dosing), the adjusted mean responses with tiotropium Respimat® 5 μg (272 mL), 2.5 μg (290 mL) and 1.25 μg (261 mL) were significantly greater than with placebo Respimat® (185 mL; p = 0.0002, p < 0.0001 and p = 0.0011, respectively). The safety and tolerability of all doses of tiotropium Respimat® were comparable with those of placebo Respimat®, with no serious adverse events and no events leading to discontinuation.

CONCLUSIONS

Tiotropium Respimat® add-on to medium-dose inhaled corticosteroids, with or without a leukotriene modifier, was efficacious in paediatric patients with symptomatic asthma and had comparable safety and tolerability with placebo Respimat®.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01383499.

Long-acting muscarinic antagonist use in adults with asthma: real-life prescribing and outcomes of add-on therapy with tiotropium bromide

Background

Randomized controlled trials indicate that addition of a long-acting muscarinic antagonist (LAMA) such as tiotropium may improve asthma control and reduce exacerbation risk in patients with poorly controlled asthma, but broader clinical studies are needed to investigate the effectiveness of LAMA in real-life asthma care.

Methods

Medical records of adults with asthma (aged ≥18 years) prescribed tiotropium were obtained from the UK Optimum Patient Care Research Database for the period 2001–2013. Patients diagnosed with chronic obstructive pulmonary disease were excluded, but no other clinical exclusions were applied. Two primary outcomes were compared in the year before (baseline) and the year after (outcome) addition of tiotropium: exacerbations (asthma-related hospital emergency department attendance or inpatient admission, or acute oral corticosteroid course) and acute respiratory events (exacerbation or antibiotic prescription with lower respiratory consultation). Secondary outcomes included lung function test results and short-acting β₂ agonist usage. The Wilcoxon signed-rank test was used for variables measured on the interval scale, the marginal homogeneity test for categorized variables, and the paired t-test for lung function indices.

Results

Of the 2,042 study patients, 83% were prescribed an inhaled corticosteroid and 68% a long-acting β₂ agonist during the baseline year; 67% were prescribed both. Comparing baseline and outcome years, the percentage of patients having at least one exacerbation decreased from 37% to 27% (P<0.001) and the percentage having at least one acute respiratory event decreased from 58% to 47% (P<0.001). There were no significant changes in lung function, and usage of short-acting β₂ agonists (in salbutamol/albuterol equivalents) increased from a median (interquartile range) of 274 (110, 548) to 329 (110, 603) μg/day (P=0.01).

Conclusion

In this real-life asthma population, addition of LAMA therapy was associated with significant decreases in the incidence of exacerbations and antibiotic prescriptions for lower respiratory tract infections in the following year.

Once-daily tiotropium Respimat(®) 5 μg is an efficacious 24-h bronchodilator in adults with symptomatic asthma

INTRODUCTION

Once-daily tiotropium Respimat(®) 5 μg is an efficacious add-on therapy to inhaled corticosteroids (ICS) with or without long-acting β2-agonists in patients with symptomatic asthma. The objective of this study was to investigate whether the dosing regimen of tiotropium (once- versus twice-daily), delivered via the Respimat(®) SoftMist™ inhaler, affected 24-h bronchodilator efficacy and safety versus placebo Respimat(®) in patients with asthma who were symptomatic despite medium-dose ICS therapy.

METHODS

A randomised, double-blind, placebo-controlled, crossover study with 4-week treatment periods of tiotropium 5 μg (once-daily, evening) and 2.5 μg (twice-daily, morning and evening). The primary efficacy end point was forced expiratory volume in 1 s (FEV1) area under the curve from 0 to 24 h (AUC)(0-24h) at the end of each treatment period. Secondary end points included peak forced expiratory volume in 1 s measured within 24 h of the last evening inhalation (peak FEV1(0-24h)), trough FEV1 measured prior to evening dosing, morning and evening peak expiratory flow (PEFam and PEFpm) and pharmacokinetic assessments.

RESULTS

94 patients were randomised (mean age 44.3 years; mean asthma duration 21.3 years) and 89 (94.7%) completed the study. Significant and comparable bronchodilation was achieved over a 24-h period with both tiotropium dosing regimens. FEV1 AUC(0-24h) response (mean ± standard error) was significantly greater with both tiotropium dosing regimens (once-daily 5 μg: 158 ± 24 mL; twice-daily 2.5 μg; 149 ± 24 mL; both p < 0.01) when compared with placebo. Improvements in peak FEV1(0-24h), trough FEV1 and pre-dose PEFam/pm with both dosing regimens versus placebo were statistically significant (all p < 0.01), with no statistically significant differences between the tiotropium treatment regimens. Total systemic exposure and tolerability were comparable between treatment regimens.

CONCLUSIONS

Lung function improvements with tiotropium Respimat(®) add-on to medium-dose ICS were sustained and similar for once-daily 5 μg and twice-daily 2.5 μg, supporting tiotropium Respimat(®) 5 μg as a once-daily bronchodilator that provides efficacy over the whole 24-h dosing interval in patients with symptomatic asthma. ClinicalTrials.gov identifier: NCT01152450.

Emerging issues in pediatric asthma: gaps in EPR-3 guidelines for infants and children

There are many complexities to the treatment of infants and children with recurrent wheezing and asthma. The National Heart, Lung and Blood Institute's (NHLBI's) Expert Panel Report-3 (EPR-3), published in 2007, provides guidance to clinicians who care for infants and children with asthma. Since that time, many important clinical trials have further informed the evidence base available to clinicians. In this manuscript, new approaches to long-term therapy, intermittent fixed-dose and dynamic dose therapies, and emerging therapies for asthma are reviewed. Further, additional gaps in guideline-based care and areas for future research are discussed.

Anticholinergics/antimuscarinic drugs in asthma

Anticholinergic alkaloids have been used for thousands of years for the relief of bronchoconstriction and other respiratory symptoms, and their use in the treatment of chronic obstructive pulmonary disease is well established. Acetylcholine, acting through muscarinic receptor (M) receptor, modulates multiple physiologic functions pertinent to asthma including airway muscle tone, mucus gland secretion, and various parameters of inflammation and remodeling. In addition, activation of M receptors may inhibit beta2 adrenoreceptor. These observations offer the rationale for the use of M receptors antagonists in the treatment of asthma. Short-acting antimuscarinic agents may be effective alone or in combination with short-acting beta agonists for the relief of acute symptoms. Long-acting antimuscarinic agents have emerged as potentially useful in the long-term treatment of difficult-to-control asthma. This review will analyze the mechanisms of action and therapeutic role of antimuscarinic agents on asthma including current guidelines regarding antimuscarinic drugs, recent studies in asthma, special populations to consider, and possible predictors of response.

Perceived 10-year change in respiratory health: reliability and predictive ability

OBJECTIVE

To investigate the usefulness of a self-reported respiratory health transition question over 10 years through reliability, ability to capture long-term asthma trajectory and predictive ability.

SETTINGS

In two 20-year cohorts (Asthma-E3N, n = 16,371, 61-88 years; EGEA, n = 1254, 27-82 years), perceived 10-year change in respiratory health ("Overall, in the last 10 years, do you think that your bronchial or respiratory health has changed?" if yes: "Has it improved/deteriorated?") was studied in relation with change in respiratory medication dispensation and lung function, with change in asthma status measured over the same period of time, and with subsequent asthma-related outcomes.

RESULTS

Perceived deterioration (14% in Asthma-E3N) was associated with increased dispensations of respiratory medications over time (from 17% with >2 dispensations in 2004 to 26% in 2010). Report of perceived deterioration (13% in EGEA) was related to a lung function decline steeper by 9.3 mL/year as compared to perceived improvement. In both cohorts, change (improvement or deterioration) was more often perceived by participants with than without asthma (>45% vs <20%) and was dominant among participants with persistent current asthma (77%). Perceived deterioration was related to poorer asthma control 7 years later and to higher use of oral corticosteroids in the following 18 months.

CONCLUSION

The proposed simple self-reported respiratory health transition question over 10 years allows predicting part of the long-term trajectory of asthma.

Tiotropium may improve asthma symptoms and lung function in asthmatic patients with irreversible airway obstruction: the real-life data

BACKGROUND AND AIMS

Some patients with asthma have poorly controlled disease despite the use of high-dose inhaled corticosteroids (ICS), long-acting β2 agonists (LABAs) and antileukotrienes. The aim of the study was to assess the effectiveness of tiotropium as an add-on therapy to the standard treatment with high-dose ICS/LABA on asthma control and lung function in patients with severe asthma.

METHODS

Of the 633 asthmatic patients, 64 (10.1%) patients with severe asthma who were add-on treated at least for 3 months were evaluated. Number of exacerbations, emergency department visits, hospitalizations and lung functions of patients belonging to 12 months before starting add-on treatment were compared with those of 12 months after starting add-on treatment.

RESULTS

The mean duration of add-on tiotropium treatment was 8.3 ± 0.5 months. For patients with severe asthma that was poorly controlled with standard combination therapy, tiotropium improved asthma control in 42.2%, decreased the number of emergency department visits in 46.9% and decreased the number of hospitalizations in 50.0% of them. The mean baseline forced expiratory volume in 1 s before add-on tiotropium was 57.5 ± 1.9% and forced vital capacity was 74.3 ± 15.6%. However, after 12 months of add-on tiotropium treatment, these rates became 65.5 ± 1.9% and 82.5 ± 15.1%, respectively. The addition of tiotropium significantly improved the percentages of the number of emergency department visits, the number of hospitalizations (P < 0.05).

CONCLUSION

Our study has suggested that, for patients with poorly controlled asthma despite of the use of ICS/LABA, the addition of tiotropium to standard care may be beneficial.

Getting control of uncontrolled asthma

Despite various treatment modalities, a large proportion of patients have asthma that remains uncontrolled. These patients remain at an increased risk of developing severe exacerbations, have a poor quality of life, and pose a high economic healthcare burden, with an estimated mean annual cost more than double that of patients with good symptom control. It is therefore important to accurately diagnose asthma and continually assess asthma control. Several validated tools are available to do this, including questionnaires, biomarker analysis, and bronchoscopy. Current guidelines advise physicians to establish a self-management program for the patient to assess and monitor asthma control. A further recommendation is the establishment of an educational action plan to increase treatment adherence and to improve asthma control. National and international guidelines provide long-term management strategies for these patients and recommend a stepwise approach for achieving and maintaining asthma control. Despite availability of a wide range of controller and reliever therapies, uncontrolled asthma remains a challenge and reflects the need for new therapeutic options. This review discusses current global guidelines for the assessment and management of asthma control and summarizes the broad spectrum of novel therapeutic agents currently under development for the treatment of asthma, including anticholinergics, chemoattractant receptor-homologous molecules expressed on T-helper 2 lymphocyte antagonists, and anti-interleukin (IL)-5, anti-IL-13, and anti-IL-4 agents.

Airway smooth muscle: a potential target for asthma therapy

PURPOSE OF REVIEW

Asthma is a major public health problem that afflicts nearly one in 20 people worldwide. Despite available treatments, asthma symptoms remain poorly controlled in a significant minority of asthma patients, especially those with severe disease. Accordingly, much ongoing effort has been directed at developing new therapeutic strategies; these efforts are described in detail below.

RECENT FINDINGS

Although mucus hypersecretion is an important component of asthma pathobiology, the primary mechanism of morbidity and mortality in asthma is excessive narrowing of the airway. The key end- effector of excessive airway narrowing is airway smooth muscle (ASM) contraction; overcoming ASM contraction is therefore a prominent therapeutic strategy. Here, we review exciting new advances aimed at ASM relaxation.

SUMMARY

Exciting advances in ASM biology have identified new therapeutic targets for the prevention or reversal of bronchoconstriction in asthma.

Tiotropium in asthmatic adolescents symptomatic despite inhaled corticosteroids: a randomised dose-ranging study

INTRODUCTION

Tiotropium, a once-daily long-acting anticholinergic agent, has been shown to be an efficacious and safe add-on treatment for adults with symptomatic asthma, despite treatment with inhaled corticosteroids (ICS). A large proportion of asthmatic adolescents have symptomatic disease despite a wide range of therapeutic options. We investigated the efficacy and safety of three doses of tiotropium, administered in the evening (via Respimat(®) SoftMist™ inhaler), versus placebo in asthmatic adolescents symptomatic despite ICS treatment.

METHODS

This randomised, double-blind, placebo-controlled, incomplete crossover study evaluated once-daily tiotropium 5 μg, 2.5 μg and 1.25 μg versus placebo in three 4-week treatment periods. Primary efficacy end point was change in peak forced expiratory volume in 1 s within 3 h post-dose from baseline (peak FEV1(0-3h)).

RESULTS

From 139 enrolled patients, 105 were randomised to receive one of four treatment sequences. Peak FEV1(0-3h) response for tiotropium 5 μg was significantly greater versus placebo (p = 0.0043). Trough FEV1 responses were significantly greater for tiotropium 5 μg (p < 0.00001) and 1.25 μg (p = 0.0134) versus placebo, but not for 2.5 μg (p = 0.0975), while FEV1 area under the curve(0-3h) responses were significant for all doses (p = 0.00001-0.0398). Overall incidence of adverse events was balanced across treatment groups, with no dose-dependent observations. The majority of adverse events were mild to moderate in intensity.

CONCLUSION

This first study of tiotropium in adolescents with symptomatic asthma demonstrates that tiotropium is well tolerated and efficacious as add-on to maintenance treatment with ICS. ClinicalTrials.gov identifier; NCT01122680.

Is there a rationale and role for long-acting anticholinergic bronchodilators in asthma?

Despite current guidelines and the range of available treatments, over a half of patients with asthma continue to suffer from poor symptomatic control and remain at risk of future worsening. Although a number of non-pharmacological measures are crucial for good clinical management of asthma, new therapeutic controller medications will have a role in the future management of the disease. Several long-acting anticholinergic bronchodilators are under investigation or are available for the treatment of respiratory diseases, including tiotropium bromide, aclidinium bromide, glycopyrronium bromide, glycopyrrolate and umeclidinium bromide, although none is yet licensed for the treatment of asthma. A recent Phase III investigation demonstrated that the once-daily long-acting anticholinergic bronchodilator tiotropium bromide improves lung function and reduces the risk of exacerbation in patients with symptomatic asthma, despite the use of inhaled corticosteroids (ICS) and long-acting β₂-agonists (LABAs). This has prompted the question of what the rationale is for long-acting anticholinergic bronchodilators in asthma. Bronchial smooth muscle contraction is the primary cause of reversible airway narrowing in asthma, and the baseline level of contraction is predominantly set by the level of ‘cholinergic tone’. Patients with asthma have increased bronchial smooth muscle tone and mucus hypersecretion, possibly as a result of elevated cholinergic activity, which anticholinergic compounds are known to reduce. Further, anticholinergic compounds may also have anti-inflammatory properties. Thus, evidence suggests that long-acting anticholinergic bronchodilators might offer benefits for the maintenance of asthma control, such as in patients failing to gain control on ICS and a LABA, or those with frequent exacerbations.

Newer glucocorticosteroids and corticosteroid resistance reversal in asthma

Inflammation is the hallmark of asthma. Glucocorticosteroids inhibit this inflammation and are the mainstay of therapy in asthma, however, they suffer from their own drawbacks. They possess high potency but their continued use has a negative influence on health. Hence, quest for a steroid with good potency but without the undesirable effects is ongoing. Besides, steroid resistance is a problem in a substantial proportion of severe asthmatics. Deeper insight into the molecular mechanism of this refractoriness has led to the successful trial of certain drugs to overcome this problem. This review attempts to discuss some of the patents related to improved glucocorticoids and those agents that have the potential to restore steroid sensitivity in severe asthmatics.

Promising future therapies for asthma

Asthma affects 300 million people worldwide and that number has been increasing especially in developed countries. The current standard of care for asthma treatment is based on 2 key pathological features of asthma, airway inflammation and airway obstruction. Improving bronchodilation can be accomplished with ultra-long acting beta2 agonists or long-acting muscarinic agonists used in combination with inhaled corticosteroids. These combinations have already been used effectively for the treatment of COPD. An inhaled phosphodiesterase inhibitor has been shown to improve bronchodilation and decrease airway inflammation. Directly altering the airway smooth muscle with bronchial thermoplasty in select patients has demonstrated long-term benefits but must be measured with immediate post procedure complications. The development of monoclonal antibodies to directly target specific cytokines has had mixed results. In eosinophilic asthma blocking IL-4, IL-5 and IL-13 have improved asthma outcomes. The promise of more directed therapy for asthma appears closer than ever with increased options available for the clinician in the near future.

Muscarinic M₃ receptors contribute to allergen-induced airway remodeling in mice

Asthma is a chronic obstructive airway disease, characterized by inflammation and remodeling. Acetylcholine contributes to symptoms by inducing bronchoconstriction via the muscarinic M3 receptor. Recent evidence suggests that bronchoconstriction can regulate airway remodeling, and therefore implies a role for the muscarinic M3 receptor. The objective of this work was to study the contribution of the muscarinic M3 receptor to allergen-induced remodeling using muscarinic M3 receptor subtype-deficient (M3R(-/-)) mice. Wild-type (WT), M1R(-/-), and M2R(-/-) mice were used as controls. C57Bl/6 mice were sensitized and challenged with ovalbumin (twice weekly for 4 wk). Control animals were challenged with saline. Allergen exposure induced goblet cell metaplasia, airway smooth muscle thickening (1.7-fold), pulmonary vascular smooth muscle remodeling (1.5-fold), and deposition of collagen I (1.7-fold) and fibronectin (1.6-fold) in the airway wall of WT mice. These effects were absent or markedly lower in M3R(-/-) mice (30-100%), whereas M1R(-/-) and M2R(-/-) mice responded similarly to WT mice. In addition, airway smooth muscle and pulmonary vascular smooth muscle mass were 35-40% lower in saline-challenged M3R(-/-) mice compared with WT mice. Interestingly, allergen-induced airway inflammation, assessed as infiltrated eosinophils and T helper type 2 cytokine expression, was similar or even enhanced in M3R(-/-) mice. Our data indicate that acetylcholine contributes to allergen-induced remodeling and smooth muscle mass via the muscarinic M3 receptor, and not via M1 or M2 receptors. No stimulatory role for muscarinic M3 receptors in allergic inflammation was observed, suggesting that the role of acetylcholine in remodeling is independent of the allergic inflammatory response, and may involve bronchoconstriction.

Novel drug targets for asthma and COPD: lessons learned from in vitro and in vivo models

Asthma and chronic obstructive pulmonary disease (COPD) are highly prevalent respiratory diseases characterized by airway inflammation, airway obstruction and airway hyperresponsiveness. Whilst current therapies, such as β-agonists and glucocorticoids, may be effective at reducing symptoms, they do not reduce disease progression. Thus, there is a need to identify new therapeutic targets. In this review, we summarize the potential of novel targets or tools, including anti-inflammatories, phosphodiesterase inhibitors, kinase inhibitors, transient receptor potential channels, vitamin D and protease inhibitors, for the treatment of asthma and COPD.

Changing face of β2-adrenergic and muscarinic receptor therapies in asthma

Despite current available treatment options, a significant proportion of patients with asthma remain uncontrolled and asthma pharmacotherapy continues to evolve. β2-Adrenergic receptor agonists play a major role as bronchodilators in asthma therapy, although new perspectives reflect the potential for bias G-protein coupled receptor signaling pathways. Due to the success of muscarinic antagonists in chronic obstructive pulmonary disease, and the elucidation that muscarinic receptors play a role in airway remodeling, muscarinic receptors represent an attractive therapeutic target in asthma. Although short-acting muscarinic antagonists are currently limited to their use in acute asthma and as alternative bronchodilators in individuals who experience side effects with β2-agonists, recent clinical trials indicate that the long-acting muscarinic antagonist, tiotropium, deserves consideration as a potential therapeutic agent for select populations. The continued evolution of anticholinergic therapy in asthma will require appropriately designed studies to assess mechanisms, efficacy and safety in asthma.

Tiotropium Respimat® in asthma: a double-blind, randomised, dose-ranging study in adult patients with moderate asthma

BACKGROUND

Tiotropium, a once-daily long-acting anticholinergic bronchodilator, when administered via Respimat® SoftMist™ inhaler (tiotropium Respimat®) significantly reduces the risk of severe exacerbations and improves lung function in patients with severe persistent asthma that is not fully controlled despite using inhaled corticosteroids (ICS) and long-acting β2-agonists. To further explore the dose-response curve in asthma, we investigated the efficacy and safety of three different doses of tiotropium Respimat® as add-on to ICS in symptomatic patients with moderate persistent asthma.

METHODS

In this randomised, double-blind, placebo-controlled, four-way crossover study, patients were randomised to tiotropium Respimat® 5 μg, 2.5 μg or 1.25 μg or placebo Respimat®, once daily in the evening. Each treatment was administered for 4 weeks, without washout between treatment periods. Eligibility criteria included ≥60% and ≤90% of predicted normal forced expiratory volume in 1 second (FEV1) and seven-question Asthma Control Questionnaire mean score of ≥1.5. Patients were required to continue maintenance treatment with stable medium-dose ICS for at least 4 weeks prior to and during the treatment period. Long-acting β2-agonists were not permitted during the treatment phase. The primary efficacy end point was peak FEV1 measured within 3 hours after dosing (peak FEV1(0-3h)) at the end of each 4-week period, analysed as a response (change from study baseline).

RESULTS

In total, 149 patients were randomised and 141 completed the study. Statistically significant improvements in peak FEV1(0-3h) response were observed with each tiotropium Respimat® dose versus placebo (all P < 0.0001). The largest difference from placebo was with tiotropium Respimat® 5 μg (188 mL). Trough FEV1 and FEV1 area under the curve (AUC)(0-3h) responses were greater with each tiotropium Respimat® dose than with placebo (all P < 0.0001), and both were greatest with 5 μg. Peak forced vital capacity (FVC)(0-3h), trough FVC and FVC AUC(0-3h) responses, versus placebo, were greatest with tiotropium Respimat® 5 μg (P < 0.0001, P = 0.0012 and P < 0.0001, respectively). Incidence of adverse events was comparable between placebo and all tiotropium Respimat® groups.

CONCLUSIONS

Once-daily tiotropium Respimat® add-on to medium-dose ICS improves lung function in symptomatic patients with moderate asthma. Overall, improvements were largest with tiotropium Respimat® 5 μg.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01233284.

Brain natriuretic peptide protects against hyperresponsiveness of human asthmatic airway smooth muscle via an epithelial cell-dependent mechanism

Brain natriuretic peptide (BNP) relaxes airways by activating natriuretic peptide receptor-A and elevating cyclic guanosine monophosphate. BNP is more effective in passively sensitized human bronchi compared with control airways. The molecular and cellular patterns involved in this signaling are unknown. The aim of this study was to investigate the influence of BNP on airway smooth muscle (ASM) cells obtained from donors with asthma and healthy donors and to identify the mechanisms involved in BNP-mediated relaxation. The contractile response of ASM cells was microscopically assessed in vitro in the presence of 1 μM BNP or with supernatant from human bronchial epithelial (BEAS-2B) cells pretreated with 1 μM BNP. We investigated the role of muscarinic M2 receptors and inducible nitric oxide synthase (iNOS), quantified the release of acetylcholine and nitric oxide (NO), and assessed the gene/protein expression of iNOS and myosin phosphatase target subunit 1 (MYPT1). Supernatant from BEAS-2B cells treated with BNP reduced the hyperreactivity of asthmatic ASM cells by shifting the potency of histamine by 1.19-fold but had no effect in healthy ASM cells. BNP was not effective directly on ASM cells. Blocking muscarinic M2-receptors and iNOS abolished the protective role of supernatant from BEAS-2B treated with BNP. BNP stimulated the release of acetylcholine (210.7 ± 11.1%) from BEAS-2B cells that in turn increased MYPT1 and iNOS gene/protein expression and enhanced NO levels in asthmatic ASM supernatant (35.0 ± 13.0%). This study provides evidence that BNP protects against bronchial hyperresponsiveness via an interaction between respiratory epithelium and ASM in subjects with asthma.