Risk of mortality associated with formoterol: a systematic review and meta-analysis

The airway smooth muscle and the pipe dream of better bronchodilators

Research on airway smooth muscle has traditionally focused on its putative detrimental role in asthma, emphasizing on how its shortening narrows the airway lumen, without much consideration about its potential role in subserving the function of the entire respiratory system. New experimental evidence on mice suggests that not only the smooth muscle is required to sustain life postnatally, but its stiffening effect on the lung tissue also protects against excessive airway narrowing and, most importantly, against small airway narrowing heterogeneity and closure. These results suggest that the smooth muscle plays an vital role in the lung periphery, essentially safeguarding alveolar ventilation by preventing small airway closure. These results also shed light on perplexing clinical observations, such as the long-standing doubts about the safety of bronchodilators. Since there seems to be an optimal level of smooth muscle contraction, at least in small airways, the therapeutic goal of maximizing the relaxation of the smooth muscle in asthma needs to be revisited. A bronchodilator with an excessive potency for inhibiting smooth muscle contraction, and that is still potent at concentrations reaching the lung periphery, may foster airway closure and air trapping, resulting in no net gain or even a decline in lung function.

Real-world evidence with a retrospective cohort of 15,968 COVID-19 hospitalized patients suggests 21 new effective treatments

PURPOSE

Despite the extensive vaccination campaigns in many countries, COVID-19 is still a major worldwide health problem because of its associated morbidity and mortality. Therefore, finding efficient treatments as fast as possible is a pressing need. Drug repurposing constitutes a convenient alternative when the need for new drugs in an unexpected medical scenario is urgent, as is the case with COVID-19.

METHODS

Using data from a central registry of electronic health records (the Andalusian Population Health Database), the effect of prior consumption of drugs for other indications previous to the hospitalization with respect to patient outcomes, including survival and lymphocyte progression, was studied on a retrospective cohort of 15,968 individuals, comprising all COVID-19 patients hospitalized in Andalusia between January and November 2020.

RESULTS

Covariate-adjusted hazard ratios and analysis of lymphocyte progression curves support a significant association between consumption of 21 different drugs and better patient survival. Contrarily, one drug, furosemide, displayed a significant increase in patient mortality.

CONCLUSIONS

In this study we have taken advantage of the availability of a regional clinical database to study the effect of drugs, which patients were taking for other indications, on their survival. The large size of the database allowed us to control covariates effectively.

Genome-wide association studies of exacerbations in children using long-acting beta2-agonists

BACKGROUND

Some children with asthma experience exacerbations despite long-acting beta2-agonist (LABA) treatment. While this variability is partly caused by genetic variation, no genome-wide study until now has investigated which genetic factors associated with risk of exacerbations despite LABA use in children with asthma. We aimed to assess whether genetic variation was associated with exacerbations in children treated with LABA from a global consortium.

METHODS

A meta-analysis of genome-wide association studies (meta-GWAS) was performed in 1,425 children and young adults with asthma (age 6-21 years) with reported regular use of LABA from six studies within the PiCA consortium using a random effects model. The primary outcome of each study was defined as any exacerbation within the past 6 or 12 months, including at least one of the following: 1) hospital admissions for asthma, 2) a course of oral corticosteroids or 3) emergency room visits because of asthma.

RESULTS

Genome-wide association results for a total of 82 996 common single nucleotide polymorphisms (SNPs, MAF ≥1%) with high imputation quality were meta-analysed. Eight independent variants were suggestively (P-value threshold ≤5 × 10^-6 ) associated with exacerbations despite LABA use.

CONCLUSION

No strong effects of single nucleotide polymorphisms (SNPs) on exacerbations during LABA use were identified. We identified two loci (TBX3 and EPHA7) that were previously implicated in the response to short-acting beta2-agonists (SABA). These loci merit further investigation in response to LABA and SABA use.

Dandelion extract relaxes mouse airway smooth muscle by blocking VDLCC and NSCC channels

BACKGROUND

Asthma is one of the main intractable diseases recognized by the international medical community. The current widely used bronchodilators for asthma-β2-adrenal receptor agonists-have limited therapeutic effects, necessitating the development of novel antiasthma drugs with increased efficacy and fewer adverse effects. In this study, we investigated the relaxant effects and underlying mechanism of an ethyl acetate extract from dandelion (EAED) on mouse airway smooth muscle.

METHODS

The effects of EAED on agonist-induced precontraction in mouse airway smooth muscle were evaluated with force measurement. Mouse lung slices were used to study the effects of EAED on bronchial smooth muscle. The intracellular Ca2+ concentration was measured using a calcium imaging system. L-type voltage-dependent calcium channel (VDLCC) and non-selective cationic channel (NSCC) currents were measured by patch-clamp. The lung functions of healthy and asthmatic mouse groups were assessed via the forced oscillation technique.

RESULTS

EAED inhibits acetylcholine-induced sustained contractions of whole airway smooth muscle by inhibiting VDLCCs, NSCCs, and some unknown channels, reduces the agonist-induced increase in the cytosolic free Ca2+ concentration in airway smooth muscle cells, blocks VDLCC and NSCC currents, and relieves the respiratory resistance of healthy and asthmatic mice.

CONCLUSIONS

EAED may have potential beneficial effects on mitigating asthma attacks.

Folium Sennae and emodin reverse airway smooth muscle contraction

The objective of this project was to find a bronchodilatory compound from herbs and clarify the mechanism. We found that the ethanol extract of Folium Sennae (EEFS) can relax airway smooth muscle (ASM). EEFS inhibited ASM contraction, induced by acetylcholine, in mouse tracheal rings and lung slices. High-performance liquid chromatography assay showed that EEFS contained emodin. Emodin had a similar reversal action. Acetylcholine-evoked contraction was also partially reduced by nifedipine (a selective inhibitor of L-type voltage-dependent Ca²⁺ channels, LVDCCs), YM-58483 (a selective inhibitor of store-operated Ca²⁺ entry, SOCE), as well as Y-27632 (an inhibitor of Rho-associated protein kinase). In addition, LVDCC- and SOCE-mediated currents and cytosolic Ca²⁺ elevations were inhibited by emodin. Emodin reversed acetylcholine-caused increases in phosphorylation of myosin phosphatase target subunit 1. Furthermore, emodin, in vivo, inhibited acetylcholine-induced respiratory system resistance in mice. These results indicate that EEFS-induced relaxation results from emodin inhibiting LVDCC, SOCE, and Ca²⁺ sensitization. These findings suggest that Folium Sennae and emodin may be new sources of bronchodilators.

Semen cassiae Extract Inhibits Contraction of Airway Smooth Muscle

β₂-adrenoceptor agonists are commonly used as bronchodilators to treat obstructive lung diseases such as asthma and chronic obstructive pulmonary disease (COPD), however, they induce severe side effects. Therefore, developing new bronchodilators is essential. Herbal plants were extracted and the extracts’ effect on airway smooth muscle (ASM) precontraction was assessed. The ethyl alcohol extract of semen cassiae (EESC) was extracted from Semen cassia. The effects of EESC on the ACh- and 80 mM K⁺-induced sustained precontraction in mouse and human ASM were evaluated. Ca²⁺ permeant ion channel currents and intracellular Ca²⁺ concentration were measured. HPLC analysis was employed to determine which compound was responsible for the EESC-induced relaxation. The EESC reversibly inhibited the ACh- and 80 mM K⁺-induced precontraction. The sustained precontraction depends on Ca²⁺ influx, and it was mediated by voltage-dependent L-type Ca²⁺ channels (LVDCCs), store-operated channels (SOCs), TRPC3/STIM/Orai channels. These channels were inhibited by aurantio-obtusin, one component of EESC. When aurantio-obtusin removed, EESC’s action disappeared. In addition, aurantio-obtusin inhibited the precontraction of mouse and human ASM and intracellular Ca²⁺ increases. These results indicate that Semen cassia-contained aurantio-obtusin inhibits sustained precontraction of ASM via inhibiting Ca²⁺-permeant ion channels, thereby, which could be used to develop new bronchodilators.

Pharmacogenetics of inhaled long-acting beta2-agonists in asthma: A systematic review

BACKGROUND

Long-acting beta2-agonists (LABA) are recommended in asthma therapy; however, not all asthma patients respond well to LABA. We performed a systematic review on genetic variants associated with LABA response in patients with asthma.

METHODS

Articles published until April 2017 were searched by two authors using PubMed and EMBASE. Pharmacogenetic studies in patients with asthma and LABA response as an outcome were included.

RESULTS

In total, 33 studies were included in this systematic review; eight focused on children (n = 6051). Nineteen studies were clinical trials, while 14 were observational studies. Studies used different outcomes to define LABA response, for example, lung function measurements (FEV₁ , PEF, MMEF, FVC), exacerbations, quality of life, and asthma symptoms. Most studies (n = 30) focused on the ADRB2 gene, encoding the beta2-adrenergic receptor. Thirty studies (n = 14 874) addressed ADRB2 rs1042713, 7 ADRB2 rs1042714 (n = 1629), and 3 ADRB2 rs1800888 (n = 1892). The association of ADRB2 rs1042713 and rs1800888 with LABA response heterogeneity was successfully replicated. Other variants were only studied in three studies but not replicated. One study focused on the ADCY9 gene. Five studies and a meta-analysis found an increased risk of exacerbations in pediatrics using LABA carrying one or two A alleles (OR 1.52 [1.17; 1.99]). These results were not confirmed in adults.

CONCLUSIONS

ADRB2 rs1042713 variant is most consistently associated with response to LABA in children but not adults. To assess the clinical value of ADRB2 rs1042713 in children with asthma using LABA, a randomized clinical trial with well-defined outcomes is needed.

Chloroform Extract of Artemisia annua L. Relaxes Mouse Airway Smooth Muscle

Artemisia annua L. belongs to the Asteraceae family, which is indigenous to China. It has valuable pharmacological properties, such as antimalarial, anti-inflammatory, and anticancer properties. However, whether it possesses antiasthma properties is unknown. In the current study, chloroform extract of Artemisia annua L. (CEAA) was prepared, and we found that CEAA completely eliminated acetylcholine (ACh) or high K⁺-elicited (80 mM) contractions of mouse tracheal rings (TRs). Patch-clamp technique and ion channel blockers were employed to explore the underlying mechanisms of the relaxant effect of CEAA. In whole-cell current recording, CEAA almost fully abolished voltage-dependent Ca²⁺ channel (VDCC) currents and markedly enhanced large conductance Ca²⁺-activated K⁺ (BK) channel currents on airway smooth muscle cells (ASMCs). In single channel current recording, CEAA increased the opening probability but had no effect on the single channel conductance of BK channels. However, under paxilline-preincubated (a selective BK channel blocker) conditions, CEAA only slightly increased BK channel currents. These results indicate that CEAA may contain active components with potent antiasthma activity. The abolished VDCCs by CEAA may mainly contribute to the underlying mechanism through which it acts as an effective antiasthmatic compound, but the enhanced BK currents might play a less important role in the antiasthmatic effects.

Concerns with beta2-agonists in pediatric asthma - a clinical perspective

Beta2-adrenoreceptor agonists (β2-agonists) are extensively used in the treatment of childhood asthma. However, there have been concerns regarding their adverse effects and safety. In 2005, the FDA commissioned a "Black Box Warning" communicating the potential for an increased risk for serious asthma exacerbations or asthma related deaths, with the regular use of LABAs. In a meta-analysis of controlled clinical trials, the incidence of severe adverse events appeared to be highest in the 4-11 year age group. Several mechanisms have been proposed regarding the risk of regular use of β2-agonists, such as masking patients' perception of worsening asthma, desensitization and downregulation of the β2-adrenoreceptor, pro-inflammatory effects of β2-agonists, pharmacogenetic effects of β2-adrenoreceptor polymorphisms and age related differences in pathophysiology of asthma. In this paper, we review β2-receptor pharmacology, discuss the concerns regarding treatment with β2-agonists in childhood asthma, and provide suggestions for clinical pediatric practice in the light of current literature.

Turning a molecule into a medicine: the development of indacaterol as a novel once-daily bronchodilator treatment for patients with COPD

Indacaterol is the first once-daily, long-acting β2-adrenergic agonist (LABA) approved for the treatment of chronic obstructive pulmonary disease (COPD). Indacaterol was developed using a combination of informed drug design and molecular chemistry to generate a β2-adrenergic agonist with a fast onset and long duration of action, enabling once-daily dosing with an acceptable safety profile. Early preclinical studies with indacaterol demonstrated these characteristics, and this promising molecule was taken into clinical development, originally for asthma treatment. Subsequent safety concerns over LABA monotherapy in patients with asthma redirected indacaterol's development to centre on COPD, where a good evidence base and guideline recommendations for bronchodilator monotherapy existed. Clinical development was initially complicated by different inhaler devices and differing doses of indacaterol. Using a phase III innovative adaptive-design clinical trial (INHANCE), indacaterol 150 and 300 μg once-daily doses were selected to be taken forward into the phase III INERGIZE programme. This programme delivered placebo-controlled and active-comparator data, including comparisons with formoterol, tiotropium and salmeterol/fluticasone, as well as the use of indacaterol in combination with tiotropium. Together, these studies provided a comprehensive assessment of the benefit-risk profile of indacaterol, allowing for regulatory submission. Indacaterol was first approved at once-daily doses of 150 and 300 μg in the European Union in 2009, followed by 150 µg in Japan (2011) and China (2012), and 75 μg in the United States (2011). To date, indacaterol is approved and marketed in more than 100 countries worldwide for once-daily maintenance treatment of COPD.

The effects of a Gly16Arg ADRB2 polymorphism on responses to salmeterol or montelukast in Japanese patients with mild persistent asthma

BACKGROUND

Long-acting β2-agonists and leukotriene receptor antagonists are two principal agents that can be added to inhaled corticosteroids (ICS) for patients with asthma that is not adequately controlled by ICS alone. The Gly16Arg genotype of the β2-adrenergic receptor (ADRB2) gene may influence the bronchodilator effects of β2-agonists. We hypothesized that differential responses to long-acting β2-agonists or leukotriene receptor antagonists might be determined partly by the Gly16Arg polymorphism in Japanese asthma patients.

MATERIALS AND METHODS

This randomized, genotype-stratified, two-period crossover study included 80 patients with mild-to-moderate asthma (35 Arg/Arg and 45 Gly/Gly individuals). The primary study outcome was the difference in peak expiratory flow (ΔPEF) (ΔPEF, l/min) by genotype after 16 weeks of treatment with salmeterol (ΔPEFsal) or montelukast (ΔPEFmon). In addition, multivariate analyses were used to identify independent factors that were predictive of responses to each treatment.

RESULTS

The mean ΔPEFsal-ΔPEFmon was 19.3±46.6 among Arg/Arg individuals and 16.8±51.5 among Gly/Gly individuals, indicating that the Gly16Arg genotype did not influence the differential bronchodilator effect of the two agents. Multivariate analysis showed that higher peripheral eosinophil counts were associated with better response to salmeterol (P<0.05).

CONCLUSION

The Gly16Arg genotype did not influence the differential bronchodilator effect of salmeterol or montelukast as an add-on therapy to ICS within 16 weeks of follow-up. Higher peripheral eosinophil counts may be associated with better responses to salmeterol in combination with ICS.

β2 adrenergic agonist attenuates house dust mite-induced allergic airway inflammation through dendritic cells

Background

Long-acting β2 adrenergic agonists (LABAs) are commonly used combined with inhaled corticosteroids (ICS) to treat asthmatic patients. Previous reports suggest that LABAs have an anti-inflammatory effect in bronchial asthma, and this should be further investigated. The aim of this study was to investigate whether LABAs inhibit allergic airway inflammation and how this occurs.

Results

We assessed the effect of the LABA formoterol (FORM) on inflammatory cell responses in airway, lung and regional lymph nodes, using an HDM-induced murine allergic asthma model in vivo. The effect of FORM on cytokine production from bone marrow derived dendritic cells (BMDCs) stimulated with HDM was evaluated in vitro. Adoptive transfer of BMDCs pulsed with HDM in the presence or absence of FORM to naïve mice was performed and the inflammatory response to subsequent HDM challenge was analyzed. FORM treatment suppressed HDM-induced changes and caused an increase in the number of eosinophils and neutrophils in bronchoalveolar lavage. The concentration of IL-4 and IL-17 in lung tissue homogenate was elevated and led to an accumulation of IL-4, IL-13, IL-5 and IL-17 producing cells in regional lymph nodes. FORM inhibited the production of IL-6 and IL-23 from BMDCs stimulated with HDM in vitro, and enhanced IL-10 production. The BMDCs adoptive transfer experiment indicated that dendritic cells mediate the effect of FORM, since FORM treatment of BMDCs in vitro attenuated airway inflammation.

Conclusion

These results suggested that FORM modulates dendritic cell function and attenuates Th2 and Th17 responses induced by HDM. Thus, we propose that the clinical significance of LABAs should be re-investigated taking into account these immune-modulating effects.

Chloride channel blockers promote relaxation of TEA-induced contraction in airway smooth muscle

Enhanced airway smooth muscle (ASM) contraction is an important component in the pathophysiology of asthma. We have shown that ligand gated chloride channels modulate ASM contractile tone during the maintenance phase of an induced contraction, however the role of chloride flux in depolarization-induced contraction remains incompletely understood. To better understand the role of chloride flux under these conditions, muscle force (human ASM, guinea pig ASM), peripheral small airway luminal area (rat ASM) and airway smooth muscle plasma membrane electrical potentials (human cultured ASM) were measured. We found ex vivo guinea pig airway rings, human ASM strips and small peripheral airways in rat lungs slices relaxed in response to niflumic acid following depolarization-induced contraction induced by K(+) channel blockade with tetraethylammonium chloride (TEA). In isolated human airway smooth muscle cells TEA induce depolarization as measured by a fluorescent indicator or whole cell patch clamp and this depolarization was reversed by niflumic acid. These findings demonstrate that ASM depolarization induced contraction is dependent on chloride channel activity. Targeting of chloride channels may be a novel approach to relax hypercontractile airway smooth muscle in bronchoconstrictive disorders.

Distinct PKA and Epac compartmentalization in airway function and plasticity

Asthma and chronic obstructive pulmonary disease (COPD) are obstructive lung diseases characterized by airway obstruction, airway inflammation and airway remodelling. Next to inflammatory cells and airway epithelial cells, airway mesenchymal cells, including airway smooth muscle cells and (myo)fibroblasts, substantially contribute to disease features by the release of inflammatory mediators, smooth muscle contraction, extracellular matrix deposition and structural changes in the airways. Current pharmacological treatment of both diseases intends to target the dynamic features of the endogenous intracellular suppressor cyclic AMP (cAMP). This review will summarize our current knowledge on cAMP and will emphasize on key discoveries and paradigm shifts reflecting the complex spatio-temporal nature of compartmentalized cAMP signalling networks in health and disease. As airway fibroblasts and airway smooth muscle cells are recognized as central players in the development and progression of asthma and COPD, we will focus on the role of cAMP signalling in their function in relation to airway function and plasticity. We will recapture on the recent identification of cAMP-sensing multi-protein complexes maintained by cAMP effectors, including A-kinase anchoring proteins (AKAPs), proteins kinase A (PKA), exchange protein directly activated by cAMP (Epac), cAMP-elevating seven-transmembrane (7TM) receptors and phosphodiesterases (PDEs) and we will report on findings indicating that the pertubation of compartmentalized cAMP signalling correlates with the pathopysiology of obstructive lung diseases. Future challenges include studies on cAMP dynamics and compartmentalization in the lung and the development of novel drugs targeting these systems for therapeutic interventions in chronic obstructive inflammatory diseases.

Pragmatic research and outcomes in asthma and COPD

Asthma and chronic obstructive pulmonary disease (COPD) are common diseases which cause patients and society considerable difficulties. These are costly diseases which cause substantial morbidity and death. Health care policy makers have made improving outcomes in asthma and COPD a priority. Application of guideline recommended approaches to asthma and COPD care in the real-life setting has been emphasized but outcomes have not improved. Failure to improve outcomes may not be because of inconsistent applications of guideline recommendations, but rather because there are difficulties implementing the Expert Panel Report III (EPR 3) method for categorizing asthma severity and the Global Initiative for Obstructive Lung Disease (GOLD) method for diagnosing COPD. As these serve as the foundation for treatment recommendations for these diseases, alternative approaches should be considered for categorizing asthma severity and identifying COPD patients. Claims-based algorithms provide an intriguing option for identifying persistent asthma patients and symptomatic COPD patients in administrative databases. These methods could be used as the basis for pragmatic research, both retrospective and prospective, on assessing outcomes of guideline recommended treatment approaches in asthma and COPD. Important questions urgently need to be answered about how guideline recommended approaches regarding use of long-acting inhaled β-agonist/inhaled corticosteroid (LABA/ICS) in asthma and long-acting inhaled anti-muscarinic agent (LAMA) and LABA/ICS in COPD affect outcomes in real-life situations.

Controversies regarding long-acting β2-agonists

PURPOSE OF REVIEW

This review examines the literature regarding the efficacy and safety of long-acting β2-agonists as add-on therapy to inhaled corticosteroids.

RECENT FINDINGS

The Global Initiative for Asthma (GINA) 2009 guidelines and the National Heart, Lung, and Blood Institute (NHLBI) 2007 asthma guidelines recommend adding long-acting β2-agonists to patients inadequately controlled on inhaled corticosteroids. These recommendations must be balanced against published data which demonstrate a signal of increased morbidity and mortality with use of long-acting β2-agonists. These conflicting data raise the question of whether or not there may be genotypic or phenotypic discriminators leading to disparate responses to long-acting β2-agonists.

SUMMARY

The combination of long-acting β2-agonists and inhaled corticosteroids demonstrates improvement in asthma control and exacerbation rates; however, long-acting β2-agonists are not recommended for use as monotherapy or without optimization of inhaled corticosteroid dose. Although the majority of asthmatic patients appear to benefit from the addition of long-acting β2-agonists, there are concerns that a small proportion of patients, including steroid-naïve patients and African Americans, may not obtain such benefits. Thus far, studies have not clearly demonstrated genotypic or phenotypic differences explaining the variability in response.

Novel expression of a functional glycine receptor chloride channel that attenuates contraction in airway smooth muscle

Airway smooth muscle (ASM) contraction is an important component of the pathophysiology of asthma. Taurine, an agonist of glycine receptor chloride (GlyR Cl(-)) channels, was found to relax contracted ASM, which led us to question whether functional GlyR Cl(-) channels are expressed in ASM. Messenger RNA for β (GLRB), α1 (GLRA1), α2 (GLRA2), and α4 (GLRA4) subunits were found in human (Homo sapiens) and guinea pig (Cavia porcellus) tracheal smooth muscle. Immunoblotting confirmed the protein expression of GLRA1 and GLRB subunits in ASM. Electrical activity of cultured human ASM cells was assessed using a fluorescent potentiometric dye and electrophysiological recordings. Glycine increased current and significantly increased fluorescence in a dose-dependent manner. The GlyR Cl(-) channel antagonist strychnine significantly blocked the effects of glycine on potentiometric fluorescence in ASM cells. Guinea pig airway ring relaxation of ACh-induced contractions by isoproterenol was significantly left-shifted in the presence of glycine. This effect of glycine was blocked by pretreatment with the GlyR Cl(-) channel antagonist strychnine. Glycine treatment during tachykinin- and acetylcholine-induced contractions significantly decreased the maintenance of muscle force compared to control. GlyR Cl(-) channels are expressed on ASM and regulate smooth muscle force and offer a novel target for therapeutic relaxation of ASM.

Treatment with budesonide/formoterol pressurized metered-dose inhaler in patients with asthma: a focus on patient-reported outcomes

In the United States, budesonide/formoterol pressurized metered-dose inhaler (pMDI) is approved for treatment of asthma in patients aged ≥12 years whose asthma is not adequately controlled with an inhaled corticosteroid (ICS) or whose disease severity clearly warrants treatment with an ICS and a long-acting β₂-adrenergic agonist. This article reviews studies of budesonide/formoterol pMDI in patients with persistent asthma, with a particular focus on patient-reported outcomes (eg, perceived onset of effect, patient satisfaction with treatment, health-related quality of life [HRQL], global assessments, sleep quality and quantity), as these measures reflect patient perceptions of asthma control and disease burden. A search of PubMed and respiratory meetings was performed to identify relevant studies. In two pivotal budesonide/formoterol pMDI studies in adolescents and adults, greater efficacy and similar tolerability were shown with budesonide/formoterol pMDI 160/9 μg and 320/9 μg twice daily versus its monocomponents or placebo. In those studies, improvements in HRQL, patient satisfaction, global assessments of asthma control, and quality of sleep also favored budesonide/formoterol pMDI compared with one or both of its monocomponents or placebo. Budesonide/formoterol pMDI has a rapid onset of effect (within 15 minutes) that patients can feel, an attribute that may have benefits for treatment adherence. In summary, budesonide/formoterol pMDI is effective and well tolerated and has additional therapeutic benefits that may be important from the patient’s perspective.

Formoterol versus short-acting beta-agonists as relief medication for adults and children with asthma

BACKGROUND

Formoterol is a long-acting beta(2)-agonist but because it has a fast onset of action it can also be used as a relief medication.

OBJECTIVES

To asses the efficacy and safety of formoterol as reliever therapy in comparison to short-acting beta(2)-agonists in adults and children with asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group Specialised Register and websites of clinical trial registers (for unpublished trial data), and we checked the Food and Drug Administration (FDA) submissions in relation to formoterol. The date of the most recent search was February 2010.

SELECTION CRITERIA

Randomised, parallel-arm trials of at least 12 weeks duration in patients of any age and severity of asthma. Studies randomised patients to any dose of as-needed formoterol versus short-acting beta(2)-agonist. Concomitant use of inhaled corticosteroids or other maintenance medication was allowed, as long as this was not part of the randomised treatment regimen.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion in the review. Outcome data were extracted by one author and checked by the second author. We sought unpublished data on primary outcomes.

MAIN RESULTS

This review includes eight studies conducted in 22,604 participants (mostly adults). Six studies compared formoterol as-needed to terbutaline whilst two studies compared formoterol with salbutamol as-needed. Background maintenance therapy varied across the trials. Asthma exacerbations and serious adverse events showed a direction of treatment effect favouring formoterol, of which one outcome reached statistical significance (exacerbations requiring a course of oral corticosteroids). In patients on short-acting beta(2)-agonists, 117 people out of 1000 had exacerbations requiring oral corticosteroids over 30 weeks, compared to 101 (95% CI 93 to 108) out of 1000 for patients on formoterol as-needed. In patients on maintenance inhaled corticosteroids there were also significantly fewer exacerbations requiring a course of oral corticosteroids on formoterol as-needed (Peto OR 0.75; 95% CI 0.62 to 0.91). There was one death per 1000 people on formoterol or on short-acting beta(2)-agonists.

AUTHORS' CONCLUSIONS

In adults, formoterol was similar to short-acting beta(2)-agonists when used as a reliever, and showed a reduction in the number of exacerbations requiring a course of oral corticosteroids. Clinicians should weigh the relatively modest benefits of formoterol as-needed against the benefits of single inhaler therapy and the potential danger of long-term use of long-acting beta(2)-agonists in some patients. We did not find evidence to recommend changes to guidelines that suggest that long-acting beta(2)-agonists should be given only to patients already taking inhaled corticosteroids.There was insufficient information reported from children in the included trials to come to any conclusion on the safety or efficacy of formoterol as relief medication for children with asthma.

Randomized controlled trial of adherence with single or combination inhaled corticosteroid/long-acting beta-agonist inhaler therapy in asthma

BACKGROUND

The inhaled corticosteroid (ICS)/long-acting beta-agonist (LABA) combination inhaler has the potential to improve adherence with ICS therapy in asthma.

OBJECTIVE

To determine whether ICS/LABA combination inhaler therapy improves adherence compared with separate inhaler use.

METHODS

In a 24-week randomized controlled parallel group study, 111 subjects were prescribed 125 microg fluticasone dipropionate (FP) and 25 microg salmeterol, 2 actuations twice daily through either a combination inhaler or separate inhalers concurrently. Medication use was recorded by covert electronic monitors. The primary outcome variable was adherence during the final 6-week period, defined as the number of doses taken as a percentage of those prescribed.

RESULTS

Complete adherence data from the final 6-week period were available for 49 and 54 subjects in the separate and combination groups, respectively. The mean (SD) adherence was 73.7% (36.0) for FP, 76.7% (30.5) for salmeterol, and 82.4% (24.5) for FP/salmeterol. There were no significant differences in adherence between FP/salmeterol and FP (-8.7%; 95% CI, -10.6 to 3.3) and salmeterol (-5.6%; 95% CI, -16.4 to 5.1). There was no significant difference in overuse among the FP, salmeterol, or FP/salmeterol groups. In 2 (4%) of 49 subjects, salmeterol was effectively taken as monotherapy during a 6-week period.

CONCLUSION

In the setting of a randomized controlled trial, use of a combination ICS/LABA inhaler does not markedly increase adherence above that observed with separate inhaler use. LABA monotherapy was observed in a small proportion of patients prescribed ICS and LABA therapy via separate inhalers.

Prescribing practices and asthma control with hydrofluoroalkane-beclomethasone and fluticasone: a real-world observational study

BACKGROUND

Long-term randomized trials comparing asthma outcomes between inhaled corticosteroids in real-world populations are lacking. As such, rigorously conducted observational studies to complement the findings of randomized trials are needed.

OBJECTIVE

We sought to compare asthma-related outcomes over 1 year as recorded in a large primary care database for patients aged 5 to 60 years receiving a first prescription (initiation population) or dose increase (step-up population) of hydrofluoroalkane (HFA)-beclomethasone or fluticasone.

METHODS

We used a retrospective matched cohort study in which patients were matched on baseline demographic and disease severity measures. Coprimary outcomes were asthma control (a composite measure comprising no unplanned visit or hospitalization for asthma, oral corticosteroids, or antibiotics for lower respiratory tract infection) and exacerbation rate.

RESULTS

More than 80% of patients in each population achieved asthma control; 10% and 16% of patients in the initiation and step-up populations, respectively, received add-on or combination therapy during the year. Fluticasone was prescribed at significantly higher doses than HFA-beclomethasone for both populations (P <or= .001). In the initiation population (n = 1319 in each cohort) the adjusted odds ratio for achieving asthma control with HFA-beclomethasone was 1.30 (95% CI, 1.02-1.65) relative to fluticasone. In the step-up population (cohorts: n = 250) the adjusted odds ratio for achieving asthma control with HFA-beclomethasone was 1.22 (95% CI, 0.66-2.26). Exacerbation rates were similar between cohorts.

CONCLUSIONS

In a real-world setting patients receiving HFA-beclomethasone had a similar or better chance of achieving asthma control at lower prescribed doses than with fluticasone.

Long-acting beta-agonists and asthma death: how useful are different study designs to evaluate the potential association?

BACKGROUND AND OBJECTIVE

There is uncertainty whether long-acting beta-agonist (LABA) drugs may increase the risk of asthma mortality. This uncertainty is partly due to the difficulty in estimating the risk of rare adverse outcomes. The aim of this paper is to consider the utility of three approaches to determine the magnitude and statistical significance of this potential association.

METHODS

Using a death rate of 9 per 10,000 subjects with asthma, derived from a meta-analysis of randomized controlled trials (RCTs) of formoterol, power calculations for a single RCT, a case-control study, and a meta-analysis of RCTs were determined.

RESULTS

For each study design, the number of subjects and events required to have adequate statistical power to detect a 1.5- and 2.0-fold increased risk of death were calculated. For a single RCT, or meta-analyses of RCTs, very large sample sizes are required. In contrast, case-control methodology represents a realistic method of estimating the risk of rare serious adverse events.

CONCLUSIONS

Major practical limitations exist in the use of RCTs to determine the potential risk of death with LABAs in the treatment of asthma. Case-control methodology may be more effective in establishing causation; however, if selection bias occurs, estimates of risk may be inaccurate.

Treatment of persistent asthma with Symbicort (budesonide/formoterol inhalation aerosol): an inhaled corticosteroid and long-acting beta2-adrenergic agonist in one pressurized metered-dose inhaler

OBJECTIVE

Budesonide/formoterol inhalation aerosol (Symbicort AstraZeneca, Wilmington, Delaware) is an inhaled corticosteroid (ICS) and long-acting beta(2)-adrenergic agonist (LABA) combination administered twice daily via one hydrofluoroalkane pressurized metered-dose inhaler (pMDI) approved in the United States for the long-term maintenance treatment of persistent asthma in patients >or=12 years of age whose asthma cannot be controlled by an ICS alone. The objective was to review efficacy, safety, and pharmacogenetic data on budesonide/formoterol pMDI in the treatment of persistent asthma.

METHODS

The authors searched PubMed and respiratory meeting databases to identify asthma studies of budesonide/formoterol pMDI. Studies involving traditional and patient-reported outcomes, safety, tolerability, or pharmacogenetics were included.

RESULTS

In two 12-week pivotal trials in adolescents and adults, treatment with budesonide/formoterol pMDI 160/4.5 microg x 2 inhalations (320/9 microg) twice daily for moderate to severe persistent asthma or 80/4.5 microg x 2 inhalations (160/9 microg) twice daily for mild to moderate persistent asthma, demonstrated greater efficacy and similar tolerability compared with placebo and the same nominal dose of its monocomponents. Comparisons with formoterol dry powder inhaler (DPI) for predose forced expiratory volume in one second (FEV(1)) and with budesonide pMDI for 12-hour mean postdose FEV(1) demonstrated the anti-inflammatory and bronchodilatory contributions of budesonide and formoterol, respectively. Evaluations of patient-reported outcomes, including asthma-specific quality of life and treatment satisfaction, further supported the clinical benefits of budesonide/formoterol pMDI. In a 52-week tolerability study of patients aged >or=12 years, budesonide/formoterol pMDI was delivered at up to double the maximum dose (640/18 microg twice daily) and demonstrated a safety profile similar to that of budesonide (640 microg twice daily), with no unexpected pattern of abnormalities. Additional studies reported that budesonide/formoterol pMDI 320/9 microg twice daily and fluticasone propionate/salmeterol DPI 250/50 microg twice daily have similar efficacy and tolerability, with significantly more patients achieving >or=15% improvement in FEV(1) within 15 minutes with budesonide/formoterol pMDI compared with fluticasone/salmeterol DPI. Moreover, inheritance of the Gly16Arg polymorphism of the beta(2)-adrenergic receptor does not appear to affect clinical outcomes with budesonide/formoterol pMDI.

CONCLUSION

Budesonide/formoterol pMDI administered twice daily is effective and generally well tolerated in patients whose asthma is not well controlled on ICS alone.

Asthma: time to confront some inconvenient truths

Despite major advances in the understanding of the pathogenesis of asthma and improvements in management, the accompanying benefits from public health initiatives and clinical practice have arguably been less than expected. For example, there are no effective public health strategies or treatment regimes that reduce the risk of developing asthma or influence its natural history. These represent priority areas for future translational research, which would need to investigate genetic and environmental interactions and vaccine strategies. In terms of asthma management it is tempting to focus on novel drug therapies; however, a case can be made that the priority is to undertake research that leads to improvements in the use of existing treatments through public health and primary care initiatives. Guidelines represent an important component of this approach, with recommendations for asthma imbedded within respiratory guidelines that can be implemented in the developing world where other acute and chronic respiratory disorders are common. This approach offers the best opportunity to close the gap between what is currently achieved in asthma management and that which is potentially achievable.

Use and safety of long-acting β2-agonists for pediatric asthma

Asthma guidelines recommend the use of long-acting β2-agonists (LABAs) as the preferred add-on therapy for adults and children over 5 years of age when asthma is inadequately controlled by inhaled corticosteroids alone. It has been suggested that LABA use may be associated with an increased risk of morbidity and mortality; however, this view is controversial since study findings have been inconsistent. While the safety profile of LABA monotherapy has been questioned, the value of concomitant inhaled corticosteroids to eliminate possible risks remains unproven. There is a paucity of efficacy and safety data for LABA use in children, and existing evidence is not sufficiently convincing to demonstrate a clear position for LABAs in the management of childhood asthma. The main aims of this article are to place LABAs in context in the management of childhood asthma and evaluate the current evidence for safety and efficacy.

Achieving asthma control in patients with moderate disease

Patients with moderate asthma are symptomatic on an ongoing basis. They are usually treated initially with low-dose inhaled corticosteroids (ICSs) supplemented with a short-acting bronchodilator as a rescue medication. Most steroid-naive patients will achieve good control with this strategy. For patients in whom adherence, inhaler technique, environmental control, and comorbidities have been addressed but who still have uncontrolled symptoms, the addition of a long-acting beta-adrenergic agonist should be considered. Some patients might require a higher dose of ICS. Leukotriene receptor antagonists might be considered as alternate initial therapy or as an add-on to maintenance therapy with an ICS. All patients should receive a structured education program emphasizing the need for ongoing maintenance treatment, even when control is achieved. Patients should also be provided with a written action plan that clearly explains which additional anti-inflammatory therapy should be taken if asthma symptoms worsen. The most effective strategy in this situation has been shown to be the quadrupling of the maintenance dose of ICS.