Therapeutic Effects of a Long-Acting Cholinergic Receptor Blocker, Tiotropium Bromide, on 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.

Effectiveness and tolerability of dual and triple combination inhaler therapies compared with each other and varying doses of inhaled corticosteroids in adolescents and adults with asthma: a systematic review and network meta-analysis

BACKGROUND

Current guidelines recommend a higher-dose inhaled corticosteroids (ICS) or adding a long-acting muscarinic antagonist (LAMA) when asthma is not controlled with medium-dose (MD) ICS/long-acting beta2-agonist (LABA) combination therapy.

OBJECTIVES

To assess the effectiveness and safety of dual (ICS/LABA) and triple therapies (ICS/LABA/LAMA) compared with each other and with varying doses of ICS in adolescents and adults with uncontrolled asthma.

SEARCH METHODS

We searched multiple databases for pre-registered randomised controlled trials (RCTs) of at least 12 weeks of study duration from 2008 to 18 February 2022.

SELECTION CRITERIA

We searched studies, including adolescents and adults with uncontrolled asthma who had been treated with, or were eligible for, MD-ICS/LABA, comparing dual and triple therapies. We excluded cluster- and cross-over RCTs.

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

We included 17,161 patients with uncontrolled asthma from 17 studies (median duration 26 weeks; mean age 49.1 years; male 40%; white 81%; mean forced expiratory volume in 1 second (MEF 1)1.9 litres and 61% predicted). The quality of included studies was generally good except for some outcomes in a few studies due to high attrition rates. Medium-dose (MD) and high-dose (HD) triple therapies reduce steroid-requiring asthma exacerbations (hazard ratio (HR) 0.84 [95% credible interval (CrI) 0.71 to 0.99] and 0.69 [0.58 to 0.82], respectively) (high-certainty evidence), but not asthma-related hospitalisations, compared to MD-ICS/LABA. High-dose triple therapy likely reduces steroid-requiring asthma exacerbations compared to MD triple therapy (HR 0.83 [95% CrI 0.69 to 0.996], [moderate certainty]). Subgroup analyses suggest the reduction in steroid-requiring exacerbations associated with triple therapies may be only for those with a history of asthma exacerbations in the previous year but not for those without. High-dose triple therapy, but not MD triple, results in a reduction in all-cause adverse events (AEs) and likely reduces dropouts due to AEs compared to MD-ICS/LABA (odds ratio (OR) 0.79 [95% CrI 0.69 to 0.90], [high certainty] and 0.50 [95% CrI 0.30 to 0.84], [moderate certainty], respectively). Triple therapy results in little to no difference in all-cause or asthma-related serious adverse events (SAEs) compared to dual therapy (high certainty). The evidence suggests triple therapy results in little or no clinically important difference in symptoms or quality of life compared to dual therapy considering the minimal clinically important differences (MCIDs) and HD-ICS/LABA is unlikely to result in any significant benefit or harm compared to MD-ICS/LABA.

AUTHORS' CONCLUSIONS

Medium-dose and HD triple therapies reduce steroid-requiring asthma exacerbations, but not asthma-related hospitalisations, compared to MD-ICS/LABA especially in those with a history of asthma exacerbations in the previous year. High-dose triple therapy is likely superior to MD triple therapy in reducing steroid-requiring asthma exacerbations. Triple therapy is unlikely to result in clinically meaningful improvement in symptoms or quality of life compared to dual therapy considering the MCIDs. High-dose triple therapy, but not MD triple, results in a reduction in all-cause AEs and likely reduces dropouts due to AEs compared to MD-ICS/LABA. Triple therapy results in little to no difference in all-cause or asthma-related SAEs compared to dual therapy. HD-ICS/LABA is unlikely to result in any significant benefit or harm compared to MD-ICS/LABA, although long-term safety of higher rather than MD- ICS remains to be demonstrated given the median duration of included studies was six months. The above findings may assist deciding on a treatment option when asthma is not controlled with MD-ICS/LABA.

Manifesto on inhaled triple therapy in asthma: an Interasma (Global Asthma Association - GAA) document

The optimal use of drug combinations for the management of asthma is providing significant results. This has prompted INTERASMA (Global Asthma Association) to take a position on inhaled triple therapy in asthma. Starting from an extensive literature review, Interasma executive committee discussed and approved this Manifesto, developed by Interasma scientific network (INES) members. The manifesto describes the evidence gathered to date and states, advocates, and proposes issues on Inhaled corticosteroid (ICS) plus Long-acting beta 2 agonist (LABA) and long-acting muscarinic antagonists (LAMA) with the aim of challenging assumptions, fostering commitment, and bringing about change.

Triple vs Dual Inhaler Therapy and Asthma Outcomes in Moderate to Severe Asthma: A Systematic Review and Meta-analysis

IMPORTANCE

The benefits and harms of adding long-acting muscarinic antagonists (LAMAs) to inhaled corticosteroids (ICS) and long-acting β2-agonists (LABAs) for moderate to severe asthma remain unclear.

OBJECTIVE

To systematically synthesize the outcomes and adverse events associated with triple therapy (ICS, LABA, and LAMA) vs dual therapy (ICS plus LABA) in children and adults with persistent uncontrolled asthma.

DATA SOURCES

MEDLINE, Embase, CENTRAL, ICTRP, FDA, and EMA databases from November 2017, to December 8, 2020, without language restriction.

STUDY SELECTION

Two investigators independently selected randomized clinical trials (RCTs) comparing triple vs dual therapy in patients with moderate to severe asthma.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted data and assessed risk of bias. Random-effects meta-analyses, including individual patient-level exacerbation data, were used. The GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach was used to assess certainty (quality) of the evidence.

MAIN OUTCOMES AND MEASURES

Severe exacerbations, asthma control (measured using the Asthma Control Questionnaire [ACQ-7], a 7-item list with each item ranging from 0 [totally controlled] to 6 [severely uncontrolled]; minimal important difference, 0.5), quality of life (measured using the Asthma-related Quality of Life [AQLQ] tool; score range, 1 [severely impaired] to 7 [no impairment]; minimal important difference, 0.5), mortality, and adverse events.

RESULTS

Twenty RCTs using 3 LAMA types that enrolled 11 894 children and adults (mean age, 52 years [range, 9-71 years]; 57.7% female) were included. High-certainty evidence showed that triple therapy vs dual therapy was significantly associated with a reduction in severe exacerbation risk (9 trials [9932 patients]; 22.7% vs 27.4%; risk ratio, 0.83 [95% CI, 0.77 to 0.90]) and an improvement in asthma control (14 trials [11 230 patients]; standardized mean difference [SMD], -0.06 [95% CI, -0.10 to -0.02]; mean difference in ACQ-7 scale, -0.04 [95% CI, -0.07 to -0.01]). There were no significant differences in asthma-related quality of life (7 trials [5247 patients]; SMD, 0.05 [95% CI, -0.03 to 0.13]; mean difference in AQLQ score, 0.05 [95% CI, -0.03 to 0.13]; moderate-certainty evidence) or mortality (17 trials [11 595 patients]; 0.12% vs 0.12%; risk ratio, 0.96 [95% CI, 0.33 to 2.75]; high-certainty evidence) between dual and triple therapy. Triple therapy was significantly associated with increased dry mouth and dysphonia (10 trials [7395 patients]; 3.0% vs 1.8%; risk ratio, 1.65 [95% CI, 1.14 to 2.38]; high-certainty evidence), but treatment-related and serious adverse events were not significantly different between groups (moderate-certainty evidence).

CONCLUSIONS AND RELEVANCE

Among children (aged 6 to 18 years) and adults with moderate to severe asthma, triple therapy, compared with dual therapy, was significantly associated with fewer severe asthma exacerbations and modest improvements in asthma control without significant differences in quality of life or mortality.

The C79G Polymorphism of the β2-Adrenergic Receptor Gene, ADRB2, and Susceptibility to Pediatric Asthma: Meta-Analysis from Review of the Literature

Background

The ADRB2 gene encodes the β2-adrenergic receptor (β2-AR). This study aimed to determine the association between the C79G polymorphism of the ADRB2 gene and its association with pediatric asthma using a meta-analysis of the published data.

Material/Methods

Review of publications up to May 2018 was from the PubMed, EMBASE, China National Knowledge Infrastructure (CNKI), and WanFang databases. The odds ratio (ORs) with 95% confidence interval (CI) were used in evaluating the strength of the reported association between the C79G polymorphism of the ADRB2 gene and pediatric asthma.

Results

There were 18 controlled studies that included 2,982 pediatric cases of asthma and 2,651 controls. Expression of the C79G polymorphism of the ADRB2 gene was significantly associated with risk of pediatric asthma associated with the C or G allele with comparison of the co-dominant model (GG vs. CC: OR, 0.69; 95% CI, 0.55–0.88) and the recessive model (GG vs. CC+CG: OR, 0.65; 95% CI, 0.53–0.81). Subgroup analysis by ethnicity showed a significantly reduced risk of pediatric asthma in Asian patients for comparison of the co-dominant model (GG vs. CC: OR, 0.59; 95% CI, 0.45–0.78), the recessive model (GG vs. CC+CG: OR, 0.58; 95% CI, 0.45–0.76), and the allelic model (G vs. C: OR, 0.89; 95% CI, 0.79–0.99).

Conclusions

The C79G polymorphism of the ADRB2 gene encoding β2-AR was associated with a reduced risk for the development of pediatric asthma, particularly in the Asian population.

Adherence to Subcutaneous Allergen Immunotherapy in Southeast Turkey: A Real-Life Study

BACKGROUND Subcutaneous immunotherapy (SCIT) in allergic rhinitis (AR) and asthma is a very effective treatment, but adherence is still a serious problem. Studies addressing real-life adherence to SCIT are rare in the literature. The aim of this study was to evaluate the adherence to SCIT in AR and asthma. MATERIAL AND METHODS The medical records of patients prescribed SCIT for treatment of AR and/or asthma were evaluated. Patients who continued the SCIT treatment as prescribed were defined as adherent, patients who stopped the treatment before the recommended period were defined as nonpersistent, and those who never started the treatment were defined as primary poor adherence. Age, gender, residence, type of SCIT, comorbidities, occupation, income, and adverse reactions were evaluated between these groups. RESULTS Ninety-five patients prescribed SCIT for the treatment of AR and/or asthma formed our cohort (female/male: 51/44). The mean (SD) age and duration of SCIT were 32.2±10.0 (range, 17-63) years, 14.4±12.7 (1.0-58.5) months, respectively. Sixty-two (65.3%) patients were adherent, (28.4%) patients were nonpersistent, and 6 (6.3%) patients were primary poor adherent. Nineteen (21.4%) patients had local adverse reactions and one (1.1%) had anaphylaxis. There were no differences between groups for age, gender, residence, type of SCIT, comorbidities, income, or occupation. The most frequent reason of nonpersistence was the cost of treatment. CONCLUSIONS Our study found that adherence to SCIT is low in a real-life setting in southeast Turkey, similar to most previous adherence studies.

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

BACKGROUND

Poorly controlled asthma and preventable exacerbations place a significant strain on healthcare, often requiring additional medications, hospital stays or treatment in the emergency department.Long-acting beta2-agonists (LABA) are the preferred add-on treatment for adults with asthma whose symptoms are not well controlled on inhaled corticosteroids (ICS), but have important safety concerns in asthma. Long-acting muscarinic antagonists (LAMA) have confirmed efficacy in chronic obstructive pulmonary disease and are now being considered as an alternative add-on therapy for people with uncontrolled asthma.

OBJECTIVES

To assess the efficacy and safety of adding a LAMA to ICS compared with adding a LABA for adults whose asthma is not well controlled on ICS alone.

SEARCH METHODS

We searched the Cochrane Airways Group's Specialised Register (CAGR) from inception to April 2015, and imposed no restriction on language of publication. We searched additional resources to pick up unpublished studies, including ClinicalTrials.gov, World Health Organization trials portal, reference lists of primary studies and existing reviews, and manufacturers' trial registries. The most recent search was conducted in April 2015.

SELECTION CRITERIA

We searched for parallel and cross-over RCTs in which adults whose asthma was not well controlled with ICS alone were randomised to receive LAMA add-on or LABA add-on for at least 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the electronic and additional searches and extracted data from study reports. We used Covidence for duplicate screening, extraction of study characteristics and numerical data, and risk of bias ratings.The pre-specified primary outcomes were exacerbations requiring oral corticosteroids (OCS), quality of life and serious adverse events.

MAIN RESULTS

We included eight studies meeting the inclusion criteria, but four double-blind, double-dummy studies of around 2000 people dominated the analyses. These four trials were between 14 and 24 weeks long, all comparing tiotropium (usually Respimat) with salmeterol on top of medium doses of ICS.Studies reporting exacerbations requiring OCS showed no difference between the two add-ons, but our confidence in the effect was low due to inconsistency between studies and because the confidence intervals (CI) included significant benefit of either treatment (odds ratio (OR) 1.05, 95% CI 0.50 to 2.18; 1753 participants; 3 studies); three more people per 1000 might have an exacerbation on LAMA, but the CIs ranged from 29 fewer to 61 more. Imprecision was also an issue for serious adverse events and exacerbations requiring hospital admission, rated low (serious adverse events) and very low quality (exacerbations requiring hospital admission), because there were so few events in the analyses.People taking LAMA scored slightly worse on two scales measuring quality of life (Asthma Quality of Life Questionnaire; AQLQ) and asthma control (Asthma Control Questionnaire; ACQ); the evidence was rated high quality but the effects were small and unlikely to be clinically significant (AQLQ: mean difference (MD) -0.12, 95% CI -0.18 to -0.05; 1745 participants; 1745; 4 studies; ACQ: MD 0.06, 95% CI 0.00 to 0.13; 1483 participants; 3 studies).There was some evidence to support small benefits of LAMA over LABA on lung function, including on our pre-specified preferred measure trough forced expiratory volume in one second (FEV1) (MD 0.05 L, 95% CI 0.01 to 0.09; 1745 participants, 4 studies). However, the effects on other measures varied, and it is not clear whether the magnitude of the differences were clinically significant.More people had adverse events on LAMA but the difference with LABA was not statistically significant.

AUTHORS' CONCLUSIONS

Direct evidence of LAMA versus LABA as add-on therapy is currently limited to studies of less than six months comparing tiotropium (Respimat) to salmeterol, and we do not know how they compare in terms of exacerbations and serious adverse events. There was moderate quality evidence that LAMAs show small benefits over LABA on some measures of lung function, and high quality evidence that LABAs are slightly better for quality of life, but the differences were all small. Given the much larger evidence base for LABA versus placebo for people whose asthma is not well controlled on ICS, the current evidence is not strong enough to say that LAMA can be substituted for LABA as add-on therapy.The results of this review, alongside pending results from related reviews assessing the use of LAMA in other clinical scenarios, will help to define the role of these drugs in asthma and it is important that they be updated as results from ongoing and planned trials emerge.