Tiotropium add-on to inhaled corticosteroids versus addition of long-acting β2-agonists for adults with asthma

Adding tiotropium or long-acting β2-agonists to inhaled corticosteroids: Asthma-related exacerbation risk and healthcare resource utilization

Background: Based on current clinical guidelines, long-acting β2-agonists (LABA) are frequently prescribed before long-acting muscarinic antagonists (LAMA) as an add-on to inhaled corticosteroids (ICS) in uncontrolled asthma. However, there is insufficient real-world evidence that supports this therapeutic approach. Objective: The objective was to compare asthma exacerbations and healthcare resource utilization in patients with asthma using the LAMA tiotropium bromide (Tio) or a LABA as an add-on to ICS (ICS + Tio or ICS/LABA) in a real-world setting. Methods: This retrospective, observational study included patients aged ≥12 years with asthma diagnoses identified in a U.S. longitudinal claims database (October 2015 to August 2020). The ICS + Tio and ICS/LABA cohorts were 1:2 propensity score matched for baseline variables. Outcomes were compared in the postmatched cohorts, and the risk of exacerbation was evaluated by using Kaplan-Meier curves. Results: After propensity score matching, there were 633 and 1266 patients in the ICS + Tio and ICS/LABA cohorts, respectively. The proportion of patients who experienced a severe or a moderate-or-severe exacerbation during follow-up was similar between the ICS + Tio versus ICS/LABA cohorts (4% versus 3%, p = 0.472, and 50% versus 45%, p = 0.050, respectively). The mean time to first severe (ICS + Tio 43.8 days versus ICS/LABA 49.4 days, p = 0.758) and moderate-or-severe exacerbation (ICS + Tio 65.8 days versus ICS/LABA 58.9 days, p = 0.474) was not statistically different between cohorts. The treatments had no effect on the risk of severe exacerbation, although it was 36% lower in ICS + Tio users than in ICS/LABA users (hazard ratio 0.64 [95% confidence interval, 0.22-1.84]). All-cause and asthma-related average monthly healthcare resource utilization were comparable between the treatments for hospitalizations and emergency department visits but were significantly greater in the ICS + Tio cohort than in the ICS/LABA cohort for asthma-related outpatient visits (p < 0.0001). Conclusion: This study provides real-world evidence that ICS + Tio may be a valid alternative when ICS/LABA cannot be used as first-line treatment for asthma maintenance therapy.

Addition of long-acting beta2 agonists or long-acting muscarinic antagonists versus doubling the dose of inhaled corticosteroids (ICS) in adolescents and adults with uncontrolled asthma with medium dose ICS: a systematic review and network meta-analysis

BACKGROUND

Inhaled corticosteroids (ICS) are the mainstay treatment for persistent asthma. Escalating treatment is required when asthma is not controlled with ICS therapy alone, which would include, but is not limited to, adding a long-acting beta2-agonist (LABA) or a long-acting muscarinic antagonist (LAMA) or doubling the dose of ICS.

OBJECTIVES

To assess the efficacy and safety of adding a LABA or LAMA to ICS therapy versus doubling the dose of ICS in adolescents and adults whose asthma is not well controlled on medium-dose (MD)-ICS using a network meta-analysis (NMA), and to provide a ranking of these treatments according to their efficacy and safety.

SEARCH METHODS

We searched the Cochrane Airways Trials Register, CENTRAL, MEDLINE, Embase, Global Health, ClinicalTrials.gov, and the World Health Organization ICTRP for pre-registered randomised controlled trials (RCTs) from January 2008 to 19 December 2022.

SELECTION CRITERIA

We searched for studies including adolescents and adults with uncontrolled asthma who had been treated with or were eligible for MD-ICS, comparing it to high-dose (HD)-ICS, ICS/LAMA, or ICS/LABA. We excluded cluster- and cross-over RCTs. Studies were of at least 12 weeks duration.

DATA COLLECTION AND ANALYSIS

We conducted a systematic review and network meta-analysis according to a previously published protocol. We used Cochrane's Screen4ME workflow to assess search results. We used Grading of Recommendations Assessment, Development and Evaluation (GRADE) to assess the certainty of evidence. The primary outcome is asthma exacerbations (moderate and severe).

MAIN RESULTS

We included 38,276 participants from 35 studies (median duration 24 weeks (range 12 to 78); mean age 44.1; 38% male; 69% white; mean forced expiratory volume in one second 2.1 litres and 68% of predicted). MD- and HD-ICS/LABA likely reduce and MD-ICS/LAMA possibly reduces moderate to severe asthma exacerbations compared to MD-ICS (hazard ratio (HR) 0.70, 95% credible interval (CrI) 0.59 to 0.82; moderate certainty; HR 0.59, 95% CrI 0.46 to 0.76; moderate certainty; and HR 0.56, 95% CrI 0.38 to 0.82; low certainty, respectively), whereas HD-ICS probably does not (HR 0.94, 95% CrI 0.70 to 1.24; moderate certainty). There is no clear evidence to suggest that any combination therapy or HD-ICS reduces severe asthma exacerbations compared to MD-ICS (low to moderate certainty). This study suggests no clinically meaningful differences in the symptom or quality of life score between dual combinations and monotherapy (low to high certainty). MD- and HD-ICS/LABA increase or likely increase the odds of Asthma Control Questionnaire (ACQ) responders at 6 and 12 months compared to MD-ICS (odds ratio (OR) 1.47, 95% CrI 1.23 to 1.76; high certainty; and OR 1.59, 95% CrI 1.31 to 1.94; high certainty at 6 months; and OR 1.61, 95% CrI 1.22 to 2.13; moderate certainty and OR 1.55, 95% CrI 1.20 to 2.00; high certainty at 12 months, respectively). MD-ICS/LAMA probably increases the odds of ACQ responders at 6 months (OR 1.32, 95% CrI 1.11 to 1.57; moderate certainty). No data were available at 12 months. There is no clear evidence to suggest that HD-ICS increases the odds of ACQ responders or improves the symptom or qualify of life score compared to MD-ICS (very low to high certainty). There is no evidence to suggest that ICS/LABA or ICS/LAMA reduces asthma-related or all-cause serious adverse events (SAEs) compared to MD-ICS (very low to high certainty). HD-ICS results in or likely results in little or no difference in the included safety outcomes compared to MD-ICS as well as HD-ICS/LABA compared to MD-ICS/LABA. The pairwise meta-analysis shows that MD-ICS/LAMA likely reduces all-cause adverse events (AEs) and results in a slight reduction in treatment discontinuation due to AEs compared to MD-ICS (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.77 to 0.96; 4 studies, 2238 participants; moderate certainty; and RR 0.51, 95% CI 0.26 to 0.99; 4 studies, 2239 participants; absolute risk reduction 10 fewer per 1000 participants; moderate certainty, respectively). The NMA evidence is in agreement with the pairwise evidence on treatment discontinuation due to AEs, but very uncertain on all-cause AEs, due to imprecision and heterogeneity.

AUTHORS' CONCLUSIONS

The review findings suggest that MD- or HD-ICS/LABA and MD-ICS/LAMA reduce moderate to severe asthma exacerbations and increase the odds of ACQ responders compared to MD-ICS whereas HD-ICS probably does not. The evidence is generally stronger for MD- and HD-ICS/LABA than for MD-ICS/LAMA primarily due to a larger evidence base. There is no evidence to suggest that ICS/LABA, ICS/LAMA, or HD-ICS/LABA reduces severe asthma exacerbations or SAEs compared to MD-ICS. MD-ICS/LAMA likely reduces all-cause AEs and results in a slight reduction in treatment discontinuation due to AEs compared to MD-ICS. The above findings may assist in deciding on a treatment option during the stepwise approach of asthma management. Longer-term safety of higher than medium-dose ICS needs to be addressed in phase 4 or observational studies given that the median duration of included studies was six months.

The Role of Long-Acting Antimuscarinic Agents in the Treatment of Asthma

The journey of using anticholinergics in the treatment of asthma started with anticholinergic-containing plants such as Datura stramonium and Atropa belladonna, followed by ipratropium bromide and continued with tiotropium, glycopyrronium, and umeclidinium. Although antimuscarinics were used in the maintenance treatment of asthma over a century ago, after a long time (since 2014), it has been recommended to be used as an add-on long-acting antimuscarinic agent (LAMA) therapy in the maintenance treatment of asthma. The airway tone controlled by the vagus nerve is increased in asthma. Allergens, toxins, or viruses cause airway inflammation and inflammation-related epithelial damage, increased sensory nerve stimulation, ganglionic and postganglionic acetylcholine (ACh) release by inflammatory mediators, intensification of ACh signaling at M1 and M3 muscarinic ACh receptors (mAChRs), and dysfunction of M2 mAChR. Optimal anticholinergic drug for asthma should effectively block M3 and M1 receptors, but have minimal effect on M2 receptors. Tiotropium, umeclidinium, and glycopyrronium are anticholinergic agents with this feature. Tiotropium has been used in a separate inhaler as an add-on treatment to inhaled corticosteroid (ICS)/long-acting β2-agonist (LABA), and glycopyrronium and umeclidinium have been used in a single inhaler as a combination of ICS/LABA/LAMA in asthma in recent years. Guidelines recommend this regimen as an optimization step for patients with severe asthma before initiating any biologic or systemic corticosteroid therapy. In this review, the history of antimuscarinic agents, their effectiveness and safety in line with randomized controlled trials, and real-life studies in asthma treatment will be discussed according to the current data.

Tiotropium Add-On and Treatable Traits in Asthma-COPD Overlap: A Real-World Pilot Study

Purpose

The ‘treatable traits’ strategy for patients with chronic inflammatory airway diseases, especially asthma and chronic obstructive pulmonary disease (COPD), is a focus of interest, because it implements precision and personalized medicine. Asthma-COPD overlap (ACO), a phenotype involving both asthma and COPD, is an important disease entity because patients with ACO have significantly worse outcomes, conferring greater economical and social burdens. Some guidelines for ACO recommend add-on therapy of long-acting muscarinic antagonists to inhaled corticosteroids and long-acting β₂ agonists. However, this approach is based on extrapolation from patients with asthma or COPD alone. Consequently, a ‘treatable traits’ approach suitable for ACO remains obscure.

Methods

A 12-week open-label cross-over pilot study was conducted in patients with ACO to investigate the effect of tiotropium bromide (TIO) 5 µg/day add-on therapy to fluticasone propionate/formoterol fumarate (FP/FM) 500/20 µg/day compared with FP/FM 500/20 µg/day alone. A 4-week run-in period and two 4-week treatment periods were included.

Results

A total of 18 male patients with stable ACO participated in this pilot study. All patients were ex-smokers. Mean values ± standard deviation (SD) for forced expiratory volume in 1 second (FEV₁) were 1.21 ± 0.49 L after the run-in period, 1.20 ± 0.51 L after the FP/FM combination therapy period, and 1.30 ± 0.48 L after the TIO add-on therapy to FP/FM period. FEV₁ values after the TIO add-on therapy FP/FM period were significantly higher than those after the run-in period (p < 0.01).

Conclusion

TIO add-on therapy to FP/FM in patients with ACO, considered difficult to treat because of the presence of both asthma and COPD, resulted in improvements in lung function parameters in this real-world pilot study, indicating the potential value of TIO add-on therapy as a “treatable traits” option for standard treatment for ACO.

Understanding the role of long-acting muscarinic antagonists in asthma treatment

OBJECTIVE

Long-acting muscarinic antagonists (LAMAs) have been used in the treatment of obstructive pulmonary diseases for years. Long-acting muscarinic antagonists were previously mainly used as bronchodilators in chronic obstructive pulmonary disease, but the use of LAMAs in the treatment of asthma has gained great interest. There is now ample evidence of the efficacy and safety of LAMAs as add-on therapy to inhaled corticosteroid (ICS) plus long-acting β₂-agonist (LABA) combinations in patients with moderate to severe uncontrolled asthma. Long-acting muscarinic antagonists have subsequently been included in asthma guidelines. This review summarizes the scientific evidence on the use of LAMAs in asthma and aims to provide a better understanding of the role of LAMAs in the asthma treatment care algorithm and the current gaps in our knowledge.

DATA SOURCES

PubMed review using the following words: long-acting muscarinic antagonists, asthma, muscarinic receptors, tiotropium, glycopyrronium, umeclidinium.

STUDY SELECTIONS

This review focused on the key trials that led to the inclusion of LAMAs in asthma guidelines. In addition, we highlighted a number of studies with other study designs and populations.

RESULTS

We identified 6 major studies that led to inclusion in asthma guidelines and 3 studies with other study designs and populations.

CONCLUSION

Long-acting muscarinic antagonists add-on therapy to ICS-LABA improves lung function, reduces exacerbations, and modestly improves asthma control in patients with moderate to severe asthma who are uncontrolled despite the use of ICS-LABA. Long-acting muscarinic antagonists are effective in all asthma phenotypes and endotypes.

Overview of severe asthma, with emphasis on pediatric patients: a review for practitioners

Asthma is the most common life-threatening chronic disease in children. Although guidelines exist for the diagnosis and treatment of asthma, treatment of severe, pediatric asthma remains difficult. Limited studies in the pediatric population on new asthma therapies, complex issues with adolescence and adherence, health disparities, and unequal access to guideline-based care complicate the care of children with severe, persistent asthma. The purpose of this review is to provide an overview of asthma, including asthma subtypes, comorbidities, and risk factors, to discuss diagnostic considerations and pitfalls and existing treatments, and then present existing and emerging therapeutic approaches to asthma management. An improved understanding of asthma heterogeneity, clinical characteristics, inflammatory patterns, and pathobiology can help further guide the management of severe asthma in children. More studies are needed in the pediatric population to understand emerging therapeutics application in children. Effective multimodal strategies tailored to individual characteristics and a commitment to address risk factors, modifiers, and health disparities may help reduce the burden of asthma in the USA.

Step-up and step-down approaches in the treatment of asthma

Introduction: Significant intraindividual and temporal variability in symptom control is a feature of asthma that requires careful monitoring and the need to periodically review and adjust therapy. Both NHLBI/NAEPP and GINA offer helpful algorithms for a stepping approach to asthma.Areas covered: The problems arisen in applying the stepwise approach to the treatment of asthma proposed by NHLBI/NAEPP and GINA algorithms and their possible alternatives.Expert opinion: The current therapeutic stepping approach to asthma, which takes into account lung function, symptoms and quality of life, is certainly useful, but it does not consider the underlying mechanisms. Furthermore, patient's overestimation or underestimation of the severity of the disease and differences in the opinions on the level of asthma control required between patients and physicians and also between physicians in both primary care and specialist settings are common and may negatively affect asthma control and future risks. A reassessment of the conventional stepping approach to management of asthma is now needed. A pragmatic approach that sets therapeutic goals for each individual and associates them with the treatable traits of asthma which, when therapeutically targeted, will in many cases help to achieve the goals, seems more reasonable than the present stepping approach.

Inhaled long-acting muscarinic antagonists in asthma - A narrative review

Long-acting muscarinic antagonists (LAMAs) have a recognised role in the management of chronic obstructive pulmonary disease. In asthma, muscarinic antagonists (both short- and long-acting) were historically considered less effective than β₂-agonists; only relatively recently have studies been conducted to evaluate the efficacy of LAMAs, as add-on to either inhaled corticosteroid (ICS) monotherapy or ICS/long-acting β₂-agonist (LABA) combinations. These studies led to the approval of the first LAMA, tiotropium, as an add-on therapy in patients with poorly controlled asthma. Subsequently, a number of single-inhaler ICS/LABA/LAMA triple therapies have been approved or are in clinical development for the management of asthma. There is now substantial evidence of the efficacy and safety of LAMAs in asthma that is uncontrolled despite treatment with an ICS/LABA combination. This regimen is recommended by GINA as an optimisation step for patients with severe asthma before any biologic or systemic corticosteroid treatment is initiated. This narrative review summarises the potential mechanisms of action of LAMAs in asthma, together with the initial clinical evidence supporting this use. We also discuss the studies that led to the approval of tiotropium for asthma and the data evaluating the efficacy and safety of the various triple therapies, before considering other potential uses for triple therapy.

Tiotropium in asthma - perspectives for the primary care physician

Asthma is a heterogeneous disease characterized by airway inflammation resulting from complex interactions between multiple hosts as well as environmental factors. As a chronic respiratory condition, asthma exerts a significant impact on patients and the healthcare system. Per the Global Initiative for Asthma (GINA), inhaled corticosteroids (ICS) with/without long-acting beta₂-agonists (LABAs) should be used as the preferred controllers for the management of asthma. Despite a range of therapeutic options, many patients with asthma remain uncontrolled, resulting in an increased risk of hospitalization and emergency room visits and a worsened quality of life. Tiotropium (Spiriva®, Boehringer Ingelheim Pharmaceuticals, Inc; 1.25 µg, two puffs, once daily), delivered via the Respimat® inhaler (Boehringer Ingelheim Pharmaceuticals, Inc.), was the first long-acting muscarinic antagonist to be approved as an add-on maintenance treatment option for patients with asthma aged ≥6 years at GINA steps 4 and 5. By binding to the muscarinic receptors M1 and M3 in the bronchial airways, tiotropium antagonizes the action of acetylcholine, leading to smooth muscle relaxation and reduced mucus secretion.The efficacy and safety of tiotropium add-on to ICS±LABA maintenance treatment have been evaluated in randomized controlled trials (RCTs) involving patients with a range of asthma severities (mild, moderate, and severe) and across age groups (children, adolescents, and adults). Add-on tiotropium was found to be well tolerated and efficacious in all RCTs. Moreover, the findings from real-world studies complement results from RCTs, showing beneficial effects of tiotropium in reducing exacerbations, hospitalization, emergency room visits, and asthma worsening.In this review article, we discuss the pathophysiology of asthma and the role of tiotropium in the management of asthma from the perspective of a primary care physician.

The Treatment of Mild and Moderate Asthma in Adults

BACKGROUND

Asthma is a chronic inflammatory airway disease that usually causes variable airway obstruction. It affects 5-10% of the German population.

METHODS

This review is based on relevant publications retrieved by a selective search, as well as on national and international guidelines on the treatment of mild and moderate asthma in adults.

RESULTS

The goal of treatment is to attain optimal asthma control with a minimal risk of exacerbations and mortality, loss of pulmonary function, and drug side effects. This can be achieved with a combination of pharmacotherapy and non-drug treatment including patient education, exercise, smoking cessation, and rehabilitation. Pharmacohterapy is based on inhaled corticosteroids (ICS) and bronchodilators. It is recommended that mild asthma should be treated only when needed, either with a fixed combination of ICS and formoterol or with short-acting bronchodilators. For moderate asthma, maintenance treatment is recommended, with an inhaled fixed combinations of ICS and long-acting beta-mimetics, possibly supplemented with longacting anticholinergic agents. Allergen immunotherapy, i.e., desensitization treatment, should be considered if the allergic component of asthma is well documented and the patient is not suffering from uncontrolled asthma. Asthma control should be monitored at regular intervals, and the treatment should be adapted accordingly.

CONCLUSION

The treatment of asthma in adults should be individually tailored, with anti-inflammatory treatment as its main component.

Pharmacology and Therapeutics of Bronchodilators Revisited

Bronchodilators remain the cornerstone of the treatment of airway disorders such as asthma and chronic obstructive pulmonary disease (COPD). There is therefore considerable interest in understanding how to optimize the use of our existing classes of bronchodilator and in identifying novel classes of bronchodilator drugs. However, new classes of bronchodilator have proved challenging to develop because many of these have no better efficacy than existing classes of bronchodilator and often have unacceptable safety profiles. Recent research has shown that optimization of bronchodilation occurs when both arms of the autonomic nervous system are affected through antagonism of muscarinic receptors to reduce the influence of parasympathetic innervation of the lung and through stimulation of β ₂-adrenoceptors (β ₂-ARs) on airway smooth muscle with β ₂-AR-selective agonists to mimic the sympathetic influence on the lung. This is currently achieved by use of fixed-dose combinations of inhaled long-acting β ₂-adrenoceptor agonists (LABAs) and long-acting muscarinic acetylcholine receptor antagonists (LAMAs). Due to the distinct mechanisms of action of LAMAs and LABAs, the additive/synergistic effects of using these drug classes together has been extensively investigated. More recently, so-called "triple inhalers" containing fixed-dose combinations of both classes of bronchodilator (dual bronchodilation) and an inhaled corticosteroid in the same inhaler have been developed. Furthermore, a number of so-called "bifunctional drugs" having two different primary pharmacological actions in the same molecule are under development. This review discusses recent advancements in knowledge on bronchodilators and bifunctional drugs for the treatment of asthma and COPD. SIGNIFICANCE STATEMENT: Since our last review in 2012, there has been considerable research to identify novel classes of bronchodilator drugs, to further understand how to optimize the use of the existing classes of bronchodilator, and to better understand the role of bifunctional drugs in the treatment of asthma and chronic obstructive pulmonary disease.

Essential Role of Pharmacists in Asthma Care and Management

Asthma, a chronic respiratory disease characterized by chronic airway inflammation, bronchial hyperresponsiveness, and reversible airflow obstruction, poses a substantial economic burden on patients and caregivers alike. Moreover, the heterogeneous nature of the disease and the presence of various phenotypes make the treatment of asthma challenging and nuanced. Despite the availability of several approved pharmacological treatments, approximately half of patients with asthma in the United States experienced exacerbations in 2016, highlighting the need for effective add-on treatments. Furthermore, asthma control remains suboptimal due to low adherence to medications, poor inhaler technique, and several patient-related factors. Importantly, the primary care setting, in which pharmacists play an integral role, represents a critical environment for providing long-term follow-up care for the effective management of chronic diseases, such as asthma. Pharmacists are uniquely positioned to ensure optimal clinical outcomes in patients with asthma since they have the clinical expertise to educate patients on their disease state and the role of asthma medications, provide training on inhalation technique, address patients’ concerns about potential side effects of medications, and improve adherence to therapy. Therefore, in this review article, we discuss the overall role of pharmacists in effective asthma care and management.

New perspectives on the role of muscarinic antagonists in asthma therapy

INTRODUCTION

There is increasing evidence that tiotropium, a long-acting muscarinic agent (LAMA), is useful in the presence of severe-uncontrolled asthma despite the optimization of therapy with inhaled corticosteroids (ICSs) and long-acting β₂ agonists (LABAs) as recommended by the current guidelines. Furthermore, in recent years there have been several  preclinical and clinical studies on the pharmacological and therapeutic impact of other LAMAs in asthma.

AREAS COVERED

We have conducted an extensive search on muscarinic antagonists in asthma therapy throughout several sources and discuss what has emerged in the last 3 years (January 2017-March 2020).

EXPERT OPINION

New evidence indicates that the effectiveness of adding a LAMA, at least tiotropium, is independent of the degree of the type 2 inflammation and age of patient. Therefore, tiotropium can be administered without the need for patient phenotyping. Umeclidinium and glycopyrronium also appear effective in asthma. Initial treatment with LAMA+ICS for those with mild asthma may be an equally effective therapeutic option as LABA+ICS but this hypothesis should be confirmed by statistically powered trials.

G Protein-Coupled Receptors in Asthma Therapy: Pharmacology and Drug Action

Asthma is a heterogeneous inflammatory disease of the airways that is associated with airway hyperresponsiveness and airflow limitation. Although asthma was once simply categorized as atopic or nonatopic, emerging analyses over the last few decades have revealed a variety of asthma endotypes that are attributed to numerous pathophysiological mechanisms. The classification of asthma by endotype is primarily routed in different profiles of airway inflammation that contribute to bronchoconstriction. Many asthma therapeutics target G protein-coupled receptors (GPCRs), which either enhance bronchodilation or prevent bronchoconstriction. Short-acting and long-acting β 2-agonists are widely used bronchodilators that signal through the activation of the β 2-adrenergic receptor. Short-acting and long-acting antagonists of muscarinic acetylcholine receptors are used to reduce bronchoconstriction by blocking the action of acetylcholine. Leukotriene antagonists that block the signaling of cysteinyl leukotriene receptor 1 are used as an add-on therapy to reduce bronchoconstriction and inflammation induced by cysteinyl leukotrienes. A number of GPCR-targeting asthma drug candidates are also in different stages of development. Among them, antagonists of prostaglandin D2 receptor 2 have advanced into phase III clinical trials. Others, including antagonists of the adenosine A2B receptor and the histamine H4 receptor, are in early stages of clinical investigation. In the past decade, significant research advancements in pharmacology, cell biology, structural biology, and molecular physiology have greatly deepened our understanding of the therapeutic roles of GPCRs in asthma and drug action on these GPCRs. This review summarizes our current understanding of GPCR signaling and pharmacology in the context of asthma treatment. SIGNIFICANCE STATEMENT: Although current treatment methods for asthma are effective for a majority of asthma patients, there are still a large number of patients with poorly controlled asthma who may experience asthma exacerbations. This review summarizes current asthma treatment methods and our understanding of signaling and pharmacology of G protein-coupled receptors (GPCRs) in asthma therapy, and discusses controversies regarding the use of GPCR drugs and new opportunities in developing GPCR-targeting therapeutics for the treatment of asthma.

Efficacy of once-daily tiotropium Respimat in adults with asthma at GINA Steps 2-5

Tiotropium Respimat is an efficacious add-on to maintenance treatment in patients with symptomatic asthma. Currently, the Global Initiative for Asthma (GINA) strategy recommends tiotropium for patients at Steps 4-5. To assess the clinical benefits of tiotropium Respimat across asthma severities, GINA Steps 2-5, a post hoc analysis of five double-blind trials (12-48-weeks; patients aged 18-75 years) investigated the effect of tiotropium Respimat, 5 μg or 2.5 μg, versus placebo, on peak forced expiratory volume in 1 s (FEV₁) within 3 h post-dose (FEV_1(0-3h)) response, and Asthma Control Questionnaire-7 (ACQ-7) responder rate. GINA step grouping was based on patients' background treatment regimen. Baseline characteristics of patients (N = 2926) were balanced between treatments. Tiotropium Respimat showed consistent improvements in lung function across GINA steps; placebo-corrected peak FEV_1(0-3h) improvements after tiotropium Respimat 5 μg and 2.5 μg were: Step 2 (Week 8), 135 mL (95% confidence interval: 84, 187) and 155 mL (103, 206); Step 3 (Week 24), 187 mL (139, 235) and 235 mL (187, 283); Step 4 (Week 24), 111 mL (63, 159) and 181 mL (35, 326); Step 5 (Week 24; 5 μg only), 164 mL (5, 323). Asthma control improved with tiotropium Respimat versus placebo, showing statistical significance (nominal P value) with tiotropium Respimat 5 μg at Step 4 (odds ratio 1.36 [1.03, 1.78]). Safety profiles were similar between treatments. In conclusion, tiotropium Respimat add-on therapy improves lung function, and may improve asthma control, in adults across disease severities.

Burden of Asthma and Role of 2.5 µg Tiotropium Respimat® as an Add-On Therapy: A Systematic Review of Phase 2/3 Trials

Introduction

Tiotropium, a long-acting muscarinic antagonist, is approved for maintenance treatment of asthma in patients at least 6 years of age in the USA. We systematically reviewed published evidence on the efficacy and safety of 2.5 µg tiotropium Respimat^® add-on therapy to inhaled corticosteroid (ICS) with or without additional controller medication(s) in children, adolescents, and adults with asthma.

Methods

We searched PubMed from inception until October 3, 2018, for phase 2 and 3 randomized controlled trials (RCTs) evaluating the effects of 2.5 µg tiotropium Respimat^® on lung function parameters in patients with asthma. We extracted adjusted mean differences for lung function data and adverse events (AEs) from relevant articles.

Results

Overall, 11 RCTs (three phase 2 and eight phase 3 studies) including 3244 patients (2.5 µg tiotropium Respimat^®, n = 1642; placebo, n = 1602) met the predefined inclusion criteria. Once-daily 2.5 µg tiotropium Respimat^® improved lung function parameters, including peak and trough forced expiratory volume in 1 s and peak and trough forced vital capacity, versus placebo. Overall, the safety profile of 2.5 µg tiotropium Respimat^® was comparable to that of placebo, with the most commonly reported AEs being asthma worsening, reduction in peak expiratory rate, nasopharyngitis, and respiratory tract infections.

Conclusion

On the basis of the results of phase 2 and 3 studies, 2.5 µg tiotropium Respimat^® as add-on to ICS therapy was safe and associated with consistent improvements in lung function in patients with asthma of varying severities across different age groups.

Funding

Development of the manuscript was funded by Boehringer Ingelheim Pharmaceuticals, Inc. (BIPI).

Electronic supplementary material

The online version of this article (10.1007/s12325-019-01062-w) contains supplementary material, which is available to authorized users.

Add-on Tiotropium in Chinese Patients With Moderate Asthma: A Pooled Subgroup Analysis of MezzoTinA-Asthma 1 and 2

Purpose

Asthma affects approximately 30 million patients in China; however, tiotropium data for Chinese patients is limited. This study aimed to assess the efficacy and safety of tiotropium in Chinese patients with moderate symptomatic asthma.

Methods

A post hoc subgroup analysis was conducted on 430 Chinese patients pooled from two 24-week, replicate phase 3 trials (NCT01172808 and NCT01172821), in which they received once-daily tiotropium 2.5 µg (Tio R2.5) or 5 µg (Tio R5) (n = 106 or 109, respectively), twice-daily salmeterol 50 µg (Sal 50) (n = 110), or placebo (n = 105), while maintaining inhaled corticosteroids (ICS). The co-primary endpoints assessed in week 24 were forced expiratory volume in 1 second (FEV1) peak_0–3h response, trough FEV1 response, and responder rate as assessed using the Asthma Control Questionnaire (ACQ).

Results

For both FEV1 peak_0–3h responses and trough FEV1 responses, the mean treatment differences were greater for Tio R2.5, Tio R5, and Sal 50 compared with placebo at 0.249 L, 0.234 L, and 0.284 L, and 0.172 L, 0.180 L, and 0.164 L, respectively (P< 0.001). The ACQ responder rate in placebo, Tio R2.5, Tio R5, and Sal 50 was 58.7%, 62.3%, 59.3%, and 69.1%, respectively. Furthermore, 11 (2.6%) of 430 patients had serious adverse events (Tio R5, n = 4; Tio R2.5, n = 1; Sal 50, n = 1; and placebo, n = 5).

Conclusions

Once-daily tiotropium, as add-on to medium-dose ICS, was effective and well tolerated for Chinese patients with moderate symptomatic asthma, consistent with the main analysis.