Long-acting beta2 agonists in the management of stable chronic obstructive pulmonary disease

Comparative Efficacy of Budesonide/Formoterol Versus Fluticasone/Salmeterol in Patients With Moderate-to-Severe Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

BACKGROUND/OBJECTIVE

To compare the efficacy of budesonide/formoterol (BF) versus fluticasone/salmeterol (FS) in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD).

METHODS

The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for studies comparing BF versus FS in the treatment of COPD from inception to July 17, 2023. Outcomes, including exacerbations, hospitalizations, pneumonia, emergency department (ED) visits for COPD, length of hospitalization, and number of exacerbations, were compared using risk ratio (RR) with corresponding 95% confidence interval (CI) or weighted mean difference (WMD) with 95% CI. All statistical analyses were performed using Stata version 12.0.

RESULTS

Ten studies comprising a total of 136,369 participants were included. Compared with those treated with FS, patients with COPD treated with BF experienced a reduced number of exacerbations (RR 0.91 [95% CI 0.83-1.00]; p = 0.040), hospitalizations (RR 0.77 [95% CI 0.67-0.88]; p < 0.001), and frequency of pneumonia (RR 0.77 [95% CI 0.64-0.92]; p = 0.05). However, no significant difference was observed between BF and FS in terms of ED visits for COPD (RR 0.87 [95% CI 0.69-1.10]; p = 0.243), length of hospitalization (WMD -0.18 [95% CI -0.62-0.27]; p = 0.437), and number of exacerbations (WMD -0.06 [95% CI -0.28-0.16]; p = 0.602). Notably, no significant heterogeneity was noted in length of hospitalization between the two groups, whereas clear heterogeneity was observed in other outcomes (I2 > 50%, p < 0.05).

CONCLUSION

Compared with FS, BF therapy appears to be a more promising treatment strategy for patients with moderate-to-severe COPD; however, this should be verified in further high-quality studies.

β2 -Adrenoceptor agonist profiling reveals biased signalling phenotypes for the β2 -adrenoceptor with possible implications for the treatment of asthma

BACKGROUND AND PURPOSE

β-Adrenoceptor agonists relieve airflow obstruction by activating β2 -adrenoceptors, which are G protein-coupled receptors (GPCRs) expressed on human airway smooth muscle (HASM) cells. The currently available β-adrenoceptor agonists are balanced agonists, however, and signal through both the stimulatory G protein (Gs )- and β-arrestin-mediated pathways. While Gs signalling is beneficial and promotes HASM relaxation, β-arrestin activation is associated with reduced Gs efficacy. In this context, biased ligands that selectively promote β2 -adrenoceptor coupling to Gs signalling represent a promising strategy to treat asthma. Here, we examined several β-adrenoceptor agonists to identify Gs -biased ligands devoid of β-arrestin-mediated effects.

EXPERIMENTAL APPROACH

Gs -biased ligands for the β2 -adrenoceptor were identified by high-throughput screening and then evaluated for Gs interaction, Gi interaction, cAMP production, β-arrestin interaction, GPCR kinase (GRK) phosphorylation of the receptor, receptor trafficking, ERK activation, and functional desensitization of the β2 -adrenoceptor.

KEY RESULTS

We identified ractopamine, dobutamine, and higenamine as Gs -biased agonists that activate the Gs /cAMP pathway upon β2 -adrenoceptor stimulation while showing minimal Gi or β-arrestin interaction. Furthermore, these compounds did not induce any receptor trafficking and had reduced GRK5-mediated phosphorylation of the β2 -adrenoceptor. Finally, we observed minimal physiological desensitization of the β2 -adrenoceptor in primary HASM cells upon treatment with biased agonists.

CONCLUSION AND IMPLICATIONS

Our work demonstrates that Gs -biased signalling through the β2 -adrenoceptor may prove to be an effective strategy to promote HASM relaxation in the treatment of asthma. Such biased compounds may also be useful in identifying the molecular mechanisms that determine biased signalling and in design of safer drugs.

Discovery of the cyclotide caripe 11 as a ligand of the cholecystokinin-2 receptor

The cholecystokinin-2 receptor (CCK2R) is a G protein-coupled receptor (GPCR) that is expressed in peripheral tissues and the central nervous system and constitutes a promising target for drug development in several diseases, such as gastrointestinal cancer. The search for ligands of this receptor over the past years mainly resulted in the discovery of a set of distinct synthetic small molecule chemicals. Here, we carried out a pharmacological screening of cyclotide-containing plant extracts using HEK293 cells transiently-expressing mouse CCK2R, and inositol phosphate (IP1) production as a readout. Our data demonstrated that cyclotide-enriched plant extracts from Oldenlandia affinis, Viola tricolor and Carapichea ipecacuanha activate the CCK2R as measured by the production of IP1. These findings prompted the isolation of a representative cyclotide, namely caripe 11 from C. ipecacuanha for detailed pharmacological analysis. Caripe 11 is a partial agonist of the CCK2R (Emax = 71%) with a moderate potency of 8.5 µM, in comparison to the endogenous full agonist cholecystokinin-8 (CCK-8; EC50 = 11.5 nM). The partial agonism of caripe 11 is further characterized by an increase on basal activity (at low concentrations) and a dextral-shift of the potency of CCK-8 (at higher concentrations) following its co-incubation with the cyclotide. Therefore, cyclotides such as caripe 11 may be explored in the future for the design and development of cyclotide-based ligands or imaging probes targeting the CCK2R and related peptide GPCRs.

Cryo-EM structures of the β3 adrenergic receptor bound to solabegron and isoproterenol

The β₃-adrenergic receptor (β₃AR) is the most essential drug target for overactive bladder and has therapeutic potentials for the treatments of type 2 diabetes and obesity. Here, we report the cryo-electron microscopy structures of the β₃AR-G_s signaling complexes with the selective agonist, solabegron and the nonselective agonist, isoproterenol. Comparison of the isoproterenol-, mirabegron-, and solabegron-bound β₃AR structures revealed that the extracellular loop 2 changes its conformation depending on the bound agonist and plays an essential role in solabegron binding. Moreover, β₃AR has an intrinsically narrow exosite, regardless of the agonist type. This structural feature clearly explains why β₃AR prefers mirabegron and solabegron, as the narrow exosite is suitable for binding with agonists with elongated shapes. Our study deepens the understanding of the binding characteristics of β₃AR agonists and may pave the way for developing β₃AR-selective drugs.

Allosteric Effect of Nanobody Binding on Ligand-Specific Active States of the β2 Adrenergic Receptor

Nanobody binding stabilizes G-protein-coupled receptors (GPCR) in a fully active state and modulates their affinity for bound ligands. However, the atomic-level basis for this allosteric regulation remains elusive. Here, we investigate the conformational changes induced by the binding of a nanobody (Nb80) on the active-like β2 adrenergic receptor (β2AR) via enhanced sampling molecular dynamics simulations. Dimensionality reduction analysis shows that Nb80 stabilizes structural features of the β2AR with an ∼14 Å outward movement of transmembrane helix 6 and a close proximity of transmembrane (TM) helices 5 and 7, and favors the fully active-like conformation of the receptor, independent of ligand binding, in contrast to the conditions under which no intracellular binding partner is bound, in which case the receptor is only stabilized in an intermediate-active state. This activation is supported by the residues located at hotspots located on TMs 5, 6, and 7, as shown by supervised machine learning methods. Besides, ligand-specific subtle differences in the conformations assumed by intracellular loop 2 and extracellular loop 2 are captured from the trajectories of various ligand-bound receptors in the presence of Nb80. Dynamic network analysis further reveals that Nb80 binding triggers tighter and stronger local communication networks between the Nb80 and the ligand-binding sites, primarily involving residues around ICL2 and the intracellular end of TM3, TM5, TM6, as well as ECL2, ECL3, and the extracellular ends of TM6 and TM7. In particular, we identify unique allosteric signal transmission mechanisms between the Nb80-binding site and the extracellular domains in conformations modulated by a full agonist, BI167107, and a G-protein-biased partial agonist, salmeterol, involving mainly TM1 and TM2, and TM5, respectively. Altogether, our results provide insights into the effect of intracellular binding partners on the GPCR activation mechanism, which should be taken into account in structure-based drug discovery.

Cryo-EM structure of the β3-adrenergic receptor reveals the molecular basis of subtype selectivity

The β₃-adrenergic receptor (β₃AR) is predominantly expressed in adipose tissue and urinary bladder and has emerged as an attractive drug target for the treatment of type 2 diabetes, obesity, and overactive bladder (OAB). Here, we report the cryogenic electron microscopy structure of the β₃AR-G_s signaling complex with the selective agonist mirabegron, a first-in-class drug for OAB. Comparison of this structure with the previously reported β₁AR and β₂AR structures reveals a receptor activation mechanism upon mirabegron binding to the orthosteric site. Notably, the narrower exosite in β₃AR creates a perpendicular pocket for mirabegron. Mutational analyses suggest that a combination of both the exosite shape and the amino-acid-residue substitutions defines the drug selectivity of the βAR agonists. Our findings provide a molecular basis for βAR subtype selectivity, allowing the design of more-selective agents with fewer adverse effects.

Biased agonism at β-adrenergic receptors

The β-adrenergic receptors (βARs) include three subtypes, β₁, β₂ and β₃. These receptors are widely expressed and regulate numerous physiological processes including cardiovascular and metabolic functions and airway tone. The βARs are also important targets in the treatment of many diseases including hypertension, heart failure and asthma. In some cases, the use of current βAR ligands to treat a disease is suboptimal and can lead to severe side effects. One strategy to potentially improve such treatments is the development of biased agonists that selectively regulate a subset of βAR signaling pathways and responses. Here we discuss the compounds identified to date that preferentially activate a G_s- or β-arrestin-mediated signaling pathway through βARs. Mechanistic insight on how these compounds bias signaling sheds light on the potential development of even more selective compounds that should have increased utility in treating disease.

Ultra high-performance liquid chromatography method development for separation of formoterol, budesonide, and related substances using an analytical quality by design approach

The application of the Quality by Design (QbD) principles in developing a new ultra high performance liquid chromatography method for the analysis of formoterol/budesonide and related substances using Fusion QbD® software is explored. The effect of various chromatographic parameters including, column stationary phase, pH, temperature, flow rate, and gradient time on separations were systematically investigated. Results show that optimal separations of these compounds in a standard solution can be achieved using a BEH C₁₈ column (2.1 × 1.7 μm × 10 cm) applying a pH of 8.2, a temperature of 35 °C, a flow rate of 0.35 mL min^-1 and a gradient time of 25 min. Furthermore, the results show that the main parameters affecting the performance of the method were the mobile phase pH, gradient time, and the temperature. For example, the most important factor for peak tailing was the pH of the mobile phase and the critical factors affecting resolution of the analytes were the gradient time and the temperature. As an application, the method was further used to analyze budesonide and formoterol in a sample obtained from a Symbicort® metered dose inhaler and it was found to provide similar separations to those obtained with the standard solution. These findings indicate that applying the QbD principles in analytical method development can be very advantageous not only in obtaining deep understanding of the effect of input parameters but also potential regulatory flexibility.

Chronic Obstructive Pulmonary Disease: A Palliative Medicine Review of the Disease, Its Therapies, and Drug Interactions

Despite significant advances in treatment, chronic obstructive pulmonary disease (COPD) remains a chronic and progressive disease that frequently leads to premature mortality. COPD is associated with a constellation of significant symptoms, including dyspnea, cough, wheezing, pain, fatigue, anxiety, depression, and insomnia, and is associated with increased morbidity. Palliative care is appropriate to support these patients. However, historically, palliative care has focused on supporting patients with malignant disease, rather than progressive chronic diseases such as COPD. Therapies for COPD often result in functional and symptomatic improvements, including health-related quality of life (HRQL), and palliative care may further improve symptoms and HRQL. Provision of usual palliative care therapies for this patient population requires understanding the pathogenesis of COPD and common disease-targeted pharmacotherapies, as well as an approach to balancing life-prolonging and HRQL care strategies. This review describes COPD and current targeted therapies and their effects on symptoms, exercise tolerance, HRQL, and survival. It is important to note that medications commonly used for symptom management in palliative care can interact with COPD medications resulting in increased risk of adverse effects, enhanced toxicity, or changes in clearance of medications. To address this, we review pharmacologic interactions with and precautions related to use of COPD therapies in conjunction with commonly used palliative care medications.

Comparative Efficacy of Budesonide/Formoterol with Budesonide, Formoterol or Placebo for Stable Chronic Obstructive Pulmonary Disease: A Meta-Analysis

BACKGROUND The 2018 Global Initiative for Chronic Obstructive Lung Disease publication suggested that the combination of bronchodilator therapy of inhaled glucocorticoid/long-acting β₂ adrenoceptor agonist is more effective in improving pulmonary function and health status in the treatment of patients with acute exacerbations than the individual components; however, it is not known whether this also the case for stable chronic obstructive pulmonary disease (COPD). The purpose of this meta-analysis was to evaluate the effectiveness of budesonide/formoterol in the maintenance and relief therapy of patients with stable COPD. MATERIAL AND METHODS An electronic search of the literature in MEDLINE, Embase, and Cochrane Central Register of Controlled Trials was undertaken to identify published randomized controlled trials (RCTs) of ≥12 weeks duration comparing the budesonide/formoterol, with budesonide, formoterol, or placebo in the treatment of patients with stable COPD. The identified RCTs were reviewed. The mean difference (MD) with corresponding 95% confidence interval (CI) was used to pool the results. RESULTS Seven high quality studies with RCTs met the inclusion criteria for meta-analysis. Compared with budesonide alone, the combination therapy of budesonide/formoterol showed significant improvement in the following spirometric indices: pre-dose forced expiratory volume in 1 second (FEV₁) (SMD: 0.26, 95% CI: 0.18, 0.34; P=0.000). In addition, versus formoterol alone, budesonide/formoterol was associated with a significant increase in pre-dose FEV₁ (SMD: 0.12, 95% CI: 0.07, 0.17; P=0.000). A similar pattern was also evident in the comparison to placebo, where budesonide/formoterol yielded greater increase in pre-dose FEV₁ (SMD: 0.24, 95% CI: 0.18, 0.30; P=0.000). Moreover, compared with other controls, the combination of budesonide-formoterol significantly improved morning peak expiratory flow and evening peak expiratory flow, significantly reduced the total score of St. George's Respiratory Questionnaire. CONCLUSIONS For stable COPD patients, compared with controls (monocomponents or placebo), budesonide/formoterol improved pulmonary function and health status. Future larger long-term RCTs are warranted to assess the beneficial clinical efficacy of budesonide/formoterol in COPD patients.

Structural insights into binding specificity, efficacy and bias of a β2AR partial agonist

Salmeterol is a partial agonist for the β2 adrenergic receptor (β2AR) and the first long-acting β2AR agonist to be widely used clinically for the treatment of asthma and chronic obstructive pulmonary disease. Salmeterol's safety and mechanism of action have both been controversial. To understand its unusual pharmacological action and partial agonism, we obtained the crystal structure of salmeterol-bound β2AR in complex with an active-state-stabilizing nanobody. The structure reveals the location of the salmeterol exosite, where sequence differences between β1AR and β2AR explain the high receptor-subtype selectivity. A structural comparison with the β2AR bound to the full agonist epinephrine reveals differences in the hydrogen-bond network involving residues Ser2045.43 and Asn2936.55. Mutagenesis and biophysical studies suggested that these interactions lead to a distinct active-state conformation that is responsible for the partial efficacy of G-protein activation and the limited β-arrestin recruitment for salmeterol.

Extracellular matrix composition is modified by β₂-agonists through cAMP in COPD

Long acting β₂-agonists (LABA) have been reported to modify the extracellular matrix (ECM) composition in the airway wall. Based on our earlier studies we here investigated the mechanism underlying the control of ECM modification by LABA in primary human airway smooth muscle cells. Cells were treated with formoterol or salmeterol (30 min) before TGF-β₁ stimulation (2-3 days) Using RT-PCT, immuno-blotting and ELISA the de novo synthesis and deposition of collagen type-I, -III, -IV and fibronectin were determined. Matrix metalloproteinases (MMP)-2 and -9 were analyzed by zymography. Both LABA activated cAMP and its corresponding transcription factor CREB within 60 min and thus partly reduced TGF-β₁-induced gene transcription of collagen type-I, -III, fibronectin and connective tissue growth factor (CTGF). The inhibitory effect of both LABA on collagen type-I and -III deposition involved a cAMP dependent mechanism, while the inhibitory effect of the two drugs on TGF-β1-induced fibronectin deposition and on CTGF secretion was independent of cAMP. Interestingly, none of the two LABA reduced CTGF-induced synthesis of collagen type-I or type-III deposition. In addition, none of the two LABA modified collagen type-IV deposition or the expression and activity of MMP-2 or MMP-9. Our results show that LABA can prevent de novo deposition of specific ECM components through cAMP dependent and independent signaling. However, they do not reduce all ECM components by the same mechanism and they do not reduce existing collagen deposits. This might explain some of the controversial reports on the anti-remodeling effect of LABA in chronic inflammatory lung diseases.

Epidemiology and management of common pulmonary diseases in older persons

Pulmonary disease prevalence increases with age and contributes to morbidity and mortality in older patients. Dyspnea in older patients is often ascribed to multiple etiologies such as medical comorbidities and deconditioning. Common pulmonary disorders are frequently overlooked as contributors to dyspnea in older patients. In addition to negative impacts on morbidity and mortality, quality of life is reduced in older patients with uncontrolled, undertreated pulmonary symptoms. The purpose of this review is to discuss the epidemiology of common pulmonary diseases, namely pneumonia, chronic obstructive pulmonary disease, asthma, lung cancer, and idiopathic pulmonary fibrosis in older patients. We will review common clinical presentations for these diseases and highlight differences between younger and older patients. We will also briefly discuss risk factors, treatment, and mortality associated with these diseases. Finally, we will address the relationship between comorbidities, pulmonary symptoms, and quality of life in older patients with pulmonary diseases.

Predictive factors for evaluation of response to fluticasone propionate/salmeterol combination in severe COPD

BACKGROUND

The predictive factors for treatment response in patients with severe chronic obstructive pulmonary disease (COPD) are unknown. We investigated predictive factors for response to fluticasone propionate/salmeterol (FSC) in severe COPD patients.

METHODS

This prospective, open-label, non-comparative study included 921 adult patients with severe COPD (baseline forced expiratory volume in 1 s (FEV(1)) <50% of predicted), a history of repeated exacerbations, and symptoms despite bronchodilator treatment. FSC (500 μg/50 μg) was delivered via an inhaler, twice a day, for 12 weeks. The primary efficacy endpoint was the response rate for inspiratory capacity (IC), FEV(1), or quality of life (QoL), assessed with the Saint George's respiratory questionnaire, at week 6 and week 12.

RESULTS

The overall response rate to FSC at 6 and 12 weeks was 79%. The corresponding rates for FEV(1), IC, and QoL were 38%, 55%, and 62%, respectively. More than 40% of patients showed a response for IC and/or QoL without being responders for FEV(1.) Overall lung function and QoL were improved. FSC was well tolerated with a safety profile consistent with that observed previously.

CONCLUSION

Nearly 80% of patients responded to FSC treatment in this real-life study. Improvements in IC and QoL at 12 weeks revealed a clinically relevant response in patients with no improvement in FEV(1). IC reversibility to salbutamol before treatment might represent, better than FEV1, a prognostic factor of response to FSC in severe COPD. Moreover these tests are easy to perform routinely and in large numbers of patients.

Combination of fluticasone propionate and salmeterol potentiates the suppression of cigarette smoke-induced IL-8 production by macrophages

Cigarette smoke is the major risk factor for the development of chronic obstructive pulmonary disease (COPD). Macrophages are suggested to orchestrate the chronic inflammatory response and tissue destruction associated with COPD by secreting interleukin (IL)-8, a major neutrophil chemoattractant. The combination of inhaled corticosteroids and long-acting beta(2)-adrenoceptor agonists are increasingly used as maintenance therapy in patients with COPD. The aim of this study was to determine whether combined fluticasone propionate, a corticosteroid, and salmeterol, a long-acting beta(2)-adrenoceptor agonist, can suppress IL-8 production by human macrophages. To mimic resident macrophages in the lung, human monocytes were cultured for 5 days in medium containing Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) and Macrophage Colony Stimulating Factor (M-CSF). In human Monocyte-Derived Macrophages, we found that cigarette smoke medium strongly enhanced IL-8 release in a time- and concentration-dependent manner. IL-8 release by cigarette smoke was significantly suppressed in a concentration-dependent manner by fluticasone and salmeterol. Coincubation of the drugs potentiated the inhibitory effect on cigarette smoke medium-induced IL-8 production and longer preincubation times resulted in more IL-8 inhibition. Interestingly, preincubation of cells with suboptimal concentration of salmeterol for 4 h before fluticasone administration for 30 min potentiates the inhibitory effect of fluticasone on IL-8 release. In conclusion, combination therapy may provide benefits over monotherapy for the treatment of COPD patients.

Comparison of bronchodilatory properties of transdermal and inhaled long-acting beta 2-agonists

BACKGROUND

Regular use of long-acting bronchodilators is recommended for symptomatic COPD patients. A transdermal type of beta 2-agonist, tulobuterol, was recently developed. This agent shows the pharmacokinetic property of a sustained serum concentration for 24h. However, little has been reported about the bronchodilatory properties of this agent.

OBJECTIVES

The aim of the present study was to compare the bronchodilatory action of transdermal beta 2-agonist tulobuterol with that of inhaled long-acting beta 2-agonist salmeterol.

METHODS

An open-label, randomized crossover study was performed. Eleven patients with stable COPD were enrolled in the study. Tulobuterol (2mg/day) or salmeterol (50 microg, twice daily) was administered in a randomized, crossover manner. Forced expiratory volume in 1s (FEV1), forced vital capacity (FVC) and inspiratory capacity (IC) were measured before administration, every 2h from 12 to 24h, and at 36 h after the initial administration.

RESULTS

Transdermal beta 2-agonist tulobuterol showed an improvement in FEV1, FVC and IC after dosing compared with those at baseline. Salmeterol also improved all parameters of FEV1, FVC and IC, and showed a greater improvement compared with the transdermal beta 2-agonist tulobuterol (p<0.05). The values of the area under the curve (AUC) of FEV1, FVC and IC during the administration of tulobuterol were 2.98+/-1.05, 1.81+/-0.98, 0.75+/-0.85 L h, respectively, and during the administration of salmeterol they were 6.39+/-1.12, 6.61+/-1.34, 4.28+/-0.91 L h, respectively.

CONCLUSION

The transdermal beta 2-agonist tulobuterol showed bronchodilatory action for at least 24h by once daily administration. However, its bronchodilatory potency was about three times less than that of the inhaled beta 2-agonist salmeterol.

Doppler echocardiographic assessment of the effects of inhaled long-acting β2-agonists on pulmonary artery pressure in COPD patients

Increase in pulmonary artery pressure (PAP), which is common in severe chronic obstructive pulmonary disease (COPD), is a predictor of mortality independent of airflow limitation. beta-agonists might slightly attenuate this increase because they exert a vasodilating effect on pulmonary circulation when systematically administered. We have investigated the acute effects of salmeterol and formoterol on echocardiographic systolic pulmonary artery pressure (sPAP) in 20 patients with COPD and a sPAP greater than 20mmHg at rest. Acute haemodynamic responses to inhaled formoterol or salmeterol were assessed in all patients, in a randomized, double-blind double-dummy fashion. On two consecutive days, patients received, in a randomized order, formoterol 12microg via Turbuhaler plus placebo via Diskus or salmeterol 50microg via Diskus plus placebo via Turbuhaler. Transthoracic Doppler echocardiography measurements of sPAP were made before and 15, 30, 60 and 180min after bronchodilator inhalation. Lung function, pulse oximetry and heart rate were also monitored at the same times. Mean sPAP significantly (p<0.05) decreased in comparison with baseline at 15, 30, and 60min post inhalation but returned towards control levels at 180min after both salmeterol and formoterol. There was no correlation between the maximum increase in FEV(1) and maximum decrease in sPAP either after inhalation of salmeterol (r(2)=0.071) or after that of formoterol (r(2)=0.0006). The increases in FEV(1) in comparison with baseline were always significant (p<0.05) from 15 to 180min post inhalation after either salmeterol or formoterol. Neither pulse oximetry nor heart rate changed in a significant manner (p>0.05). This study demonstrated that salmeterol and formoterol were equally beneficial for pulmonary haemodynamics in patients with COPD. A direct vasodilatation due to the activation of beta-adrenoceptors that are present in pulmonary vessels is a likely mechanism of their action in inducing the decrease in sPAP.

Efeito da teofilina associada ao beta2-agonista inalatório de curta ou longa duração, em pacientes com doença pulmonar obstrutiva crônica estável: revisão sistemática

OBJETIVOS: Avaliar se o tratamento com teofilina associada ao beta2-agonista inalatório de curta ou longa duração é mais eficaz que o placebo e que o uso isolado de cada um dos fármacos, para os pacientes com doença pulmonar obstrutiva crônica estável. MÉTODOS: Realizou-se uma revisão sistemática com metanálise, sendo selecionados todos os ensaios clínicos aleatórios e duplo-cegos encontrados na literatura. RESULTADOS: Foram incluídos oito estudos. Teofilina associada ao beta2-agonista vs. placebo: houve melhora estatisticamente significante para o VEF1 (L), com média 0,27 (IC95% 0,11 a 0,43); e para a dispnéia, com média -0,78 (IC95% -1,26 a -0,29). Teofilina associada ao beta2-agonista vs. beta2-agonista isolado: nenhuma das metanálises realizadas detectou diferença entre os grupos. Teofilina associada ao beta2-agonista vs. teofilina isolada: houve melhora estatisticamente significante para a dispnéia, com média -0,19 (IC95% -0,34 a -0,04). CONCLUSÕES: Em pacientes com doença pulmonar obstrutiva crônica estável: 1) teofilina associada ao beta2-agonista é mais eficaz que o placebo, em relação ao VEF1 e dispnéia; 2a) teofilina associada ao beta2-agonista é mais eficaz que a teofilina isolada, em relação à dispnéia; e 2b) teofilina associada ao beta2-agonista não é mais eficaz que o beta2-agonista isolado, para quaisquer das variáveis estudadas.

The impact of long-term conventional treatment for overlap syndrome (obstructive sleep apnea and chronic obstructive pulmonary disease) on concurrent erectile dysfunction

PURPOSE

To assess the improvement of concurrent erectile dysfunction (ED) in men with overlap syndrome (obstructive sleep apnea and chronic obstructive pulmonary disease), treated with continuous positive airway pressure (CPAP) and bronchodilators.

MATERIAL AND METHODS

We evaluated 48 men of a mean age of 52.8+/-10 years suffering from both obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD), and concurrent ED. They were treated with conventional for pulmonary obstruction therapy (CPAP and bronchodilators) for 6 months and then their erectile function (EF) status was reassessed. ED was considered as improved, if ED intensity score increased for at least five points compared to that of baseline. The determinants for improvement of ED were also evaluated, as well as patient's personal degree of satisfaction with the treatment they received as far as the disorder was concerned.

RESULTS

EF was improved in 12 patients (25%), but only two thirds of them were satisfied with the grade of improvement after treatment. ED improvement was related positively with age and apnea/hypopnea index and negatively with ED duration. ED intensity score, O(2) saturation at night and BMI were not significantly related to the outcome of EF improvement.

CONCLUSIONS

Conventional treatment for OSA and COPD, has a positive effect on concurrent ED on the minority of patients. This effect is possibly due to the improvement of respiration during sleep with CPAP and of oxygenation with bronchodilators continuously. Of the improved men, one third was not satisfied with the impact of this treatment modality on their EF. It is likely that specific for ED treatment is needed in these individuals.

Improved outcomes in patients with chronic obstructive pulmonary disease treated with salmeterol compared with placebo/usual therapy: results of a meta-analysis

Background

Several studies have demonstrated that long-acting β₂-agonists such as salmeterol are beneficial in chronic obstructive pulmonary disease (COPD). A meta-analysis was therefore conducted to review studies in COPD to provide pooled estimates of the effect of salmeterol 50 mcg taken twice daily in addition to usual therapy on several clinically relevant endpoints, when compared with placebo/usual therapy.

Methods

An extensive search of literature and clinical trial databases was conducted using the terms salmeterol, COPD, chronic, obstructive, bronchitis and emphysema. Nine randomized, double-blind, parallel-group, placebo-controlled trials of ≥12 week duration with salmeterol 50 mcg bid treatment in COPD were included (>3500 patients), with a further 14 trials excluded due to study design or reporting timelines. All patients were included, and a sub-group of subjects (84%) with poorly reversible COPD were considered separately. Statistical testing was carried out at the 5% level, except for interaction testing which was carried out at the 10% level.

Results

Patients treated with salmeterol over 12 months were less likely to withdraw early from the studies (19% patients compared with 25% on their current usual therapy, p < 0.001), less likely to suffer a moderate/severe exacerbation (34% compared with 39%, p < 0.0001) and had a greater increase in average FEV₁ (73 mL difference vs placebo/usual therapy, p < 0.0001). Similar differences were found at 3 and 6 months. At all time points, more patients experienced an improvement in health status and also a greater change with salmeterol than with placebo/usual therapy (p < 0.002). There was no evidence of tachyphylaxis to salmeterol over 12 months.

Conclusion

The meta-analysis confirmed clinically and statistically significant, sustained and consistent superiority of salmeterol 50 mcg bid over placebo/usual therapy on a broad range of outcome measures.

Inhaled beta2-adrenoceptor agonists: cardiovascular safety in patients with obstructive lung disease

Although large surveys have documented the favourable safety profile of beta(2)-adrenoceptor agonists (beta(2)-agonists) and, above all, that of the long-acting agents, the presence in the literature of reports of adverse cardiovascular events in patients with obstructive airway disease must induce physicians to consider this eventuality. The coexistence of beta(1)- and beta(2)-adrenoceptors in the heart clearly indicates that beta(2)-agonists do have some effect on the heart, even when they are highly selective. It should also be taken into account that the beta(2)-agonists utilised in clinical practice have differing selectivities and potencies. beta(2)-agonist use has, in effect, been associated with an increased risk of myocardial infarction, congestive heart failure, cardiac arrest and sudden cardiac death. Moreover, patients who have either asthma or chronic obstructive pulmonary disease may be at increased risk of cardiovascular complications because these diseases amplify the impact of these agents on the heart and, unfortunately, are a confounding factor when the impact of beta(2)-agonists on the heart is evaluated. Whatever the case may be, this effect is of particular concern for those patients with underlying cardiac conditions. Therefore, beta(2)-agonists must always be used with caution in patients with cardiopathies because these agents may precipitate the concomitant cardiac disease.

Biological targets for therapeutic interventions in COPD: clinical potential

COPD is a widespread inflammatory respiratory disorder characterized by a progressive, poorly reversible airflow limitation. Currently available therapies are mostly based on those used to treat asthma. However, such compounds are not able to effectively reduce the gradual functional deterioration, as well as the ongoing airway and lung inflammation occurring in COPD patients. Therefore, there is an urgent need to improve the efficacy of the existing drug classes and to develop new treatments, targeting the main cellular and molecular mechanisms underlying disease pathogenesis. These therapeutic strategies will be highlighted in the present review.

The Rationale for Pharmacologic Therapy in Stable Chronic Obstructive Pulmonary Disease

The structural changes in airways and alveoli that characterize chronic obstructive pulmonary disease (COPD) result from an abnormal and persistent inflammatory reaction to inhaled noxious particles or gases, notably tobacco smoke. This remodeling of the lung leads to irreversible airflow obstruction. However, COPD should be viewed by clinicians as a treatable condition, since most patients with COPD have an additional reversible component related to increased bronchomotor tone. The use of bronchodilators, especially anticholinergics and beta2-agonists, results in a reduction in airway smooth muscle tone and airflow resistance; this translates into marked improvement in significant clinical outcomes such as dyspnea, quality of life, and exercise capacity. An increasing amount of evidence supports the idea that long-acting agents have more significant impact in these parameters than the short-acting preparations.

Long acting beta2 agonists for stable chronic obstructive pulmonary disease with poor reversibility: a systematic review of randomised controlled trials

Background

The long acting β2-agonists, salmeterol and formoterol, have been recommended, by some, as first line treatment of stable chronic obstructive pulmonary disease (COPD). We reviewed evidence of efficacy and safety when compared with placebo or anticholinergic agents in patients with poorly reversible COPD.

Methods

After searching MEDLINE, EMBASE, HealthSTAR, BIOSIS Previews, PASCAL, ToxFile, SciSearch, the Cochrane Library, and PubMed, as well as Web sites, selected journals, reference lists, and contacting drug manufacturers, two reviewers independently screened reports of randomised controlled trials of parallel or crossover design lasting four weeks or longer and including patients with a forced expiratory volume in one second (FEV1) ≤ 75% of predicted, a ratio of FEV1 to forced vital capacity (FVC) ≤ 88% of predicted, and < 15% improvement from baseline FEV1 after a dose of a β2 agonist. We included trials comparing salmeterol or formoterol with placebo or with ipratropium bromide and reporting one of these outcomes: lung function; exercise capacity; quality of life scores; dyspnea; exacerbations; rescue inhaler use; incidence of tachycardia, hypokalemia, or dry mouth. Two reviewers assessed the quality of included reports using the Jadad scale and allocation concealment, and abstracted data.

Results

Twelve trials satisfied our inclusion criteria; eight were high quality (Jadad score >2) and four were low quality (≤ 2). The adequacy of allocation concealment was unclear in all of them. We did not perform a meta-analysis due to differences in trial design and how outcomes were reported.

Two trials comparing salmeterol with ipratropium did not detect differences; one trial comparing formoterol and ipratropium described greater improvement with formoterol in morning PEFR (15.3 versus 7.1 l/min, p = 0.040).

Of twelve trials comparing long acting β2 agonists with placebo, six reported no improvement in exercise capacity, eleven reported improvements in FEV1 lung function (one reported no improvement), six reported less rescue inhaler usage (one reported no difference) and five reported improved dyspnea scores (two reported no improvement). Differences in quality of life were detected in one salmeterol trial ; however, two salmeterol, and one formoterol trial reported no differences. Adverse effects of interest were not reported.

Conclusion

In terms of clinical outcomes and safety, we could not find convincing evidence that salmeterol and formoterol have demonstrated advantages to ipratropium, a less expensive drug, for patients with stable COPD and poor reversibility. Compared to placebo, we found evidence of reduced rescue inhaler usage and improved spirometric outcomes without a significant impact on quality of life or exercise capacity.

Optimization and validation of a gas chromatographic method for analysis of (RS,SR)-diastereoisomeric impurity in formoterol fumarate

A gas chromatographic method for the determination of formoterol (RS,SR)-diastereoisomer, a process impurity, in formoterol fumarate was optimized and validated. The method involves silylation of formoterol fumarate with N-(trimethylsilyl)imidazole in N,N-dimethylformamide at room temperature in an autosampler vial to produce trimethylsilyl derivatives of the enantiomers prior to GC analysis. The optimized silylation and separation conditions, respectively, produced good yield and resolution of the analytes. The method appears to be convenient and fast, and permits accurate determination of (RS,SR)-diastereoisomer in formoterol fumarate with adequate precision (R.S.D. = 3.0%, n = 9) and sensitivity (DL < 0.01%) when compared with the official liquid chromatographic limit test method of Pharmeuropa. The method was successfully applied to quality control of commercial formoterol fumarate for their (RS,SR)-diastereoisomer contents.

Inhaled Combination Therapy With Long-Acting β 2 -Agonists and Corticosteroids in Stable COPD

Long-acting beta(2)-agonists (LABAs) have been shown to be effective first-line bronchodilators in the treatment of COPD patients, and inhaled corticosteroids (ICSs) have been shown to reduce the frequency and/or severity of exacerbations in COPD patients. The concomitant use of a LABA and an ICS can influence both airway obstruction (ie, smooth muscle contraction, increased cholinergic tone, and loss of elastic recoil), and airway inflammation (ie, increased numbers of neutrophils, macrophages, and CD8+ lymphocytes, elevated interleukin-8 and tumor necrosis factor-alpha levels, and protease/antiprotease imbalance). They are also able to reduce the total number of bacteria adhering to the respiratory mucosa in a concentration-dependent manner without altering the bacterial tropism for mucosa, and to preserve ciliated cells. Several clinical trials support the concept of inhaled combination therapy with LABAs and corticosteroids in stable COPD patients. This type of therapy not only improves airflow obstruction but also provides clinical benefits, as manifested by sustained reduction in overall symptoms, improvements in health-related quality of life, and reductions in exacerbations. All of these effects are very important because, despite recent advances in our understanding of COPD and its treatment, therapy remains suboptimal for a considerable number of patients.

The pharmacodynamic effects of single inhaled doses of formoterol, tiotropium and their combination in patients with COPD

The aim of this double-blind, double-dummy, cross-over, randomized, pilot study was to compare the acute bronchodilator efficacy of a single dose of formoterol with that of tiotropium in patients with stable chronic obstructive pulmonary disease (COPD). Because the potential of tiotropium for additive effects is yet unknown, the acute effects of adding this anticholinergic agent to formoterol were also explored. A total of 20 outpatients with stable COPD were enrolled. Single doses of 12 microg formoterol, 18 microg tiotropium, and 12 microg formoterol+18 microg tiotropium were given. Serial measurements of FEV1 were performed over 24 h. Formoterol, either alone or in combination with tiotropium, elicited a significantly faster onset of action and showed a trend for a greater maximum bronchodilation than tiotropium alone. At 24 h, mean FEV1 continued to be significantly higher than pre-dosing value following tiotropium and formoterol+tiotropium. These findings indicate that formoterol and tiotropium have different profiles that make both agents attractive alternatives in the treatment of stable COPD. Since tiotropium ensures prolonged bronchodilation, whereas formoterol adds fast onset and a greater peak effect, the two drugs appear complementary.

Validation of a RP-HPLC method for the assay of formoterol and its related substances in formoterol fumarate dihydrate drug substance

A stability-indicating reversed-phase high performance liquid chromatographic (HPLC) method has been developed and validated for the assay of formoterol fumarate and the related substances, namely, formoterol fumarate desformyl and formoterol fumarate acetamide analogs, in the active pharmaceutical ingredient. The separation was achieved by isocratic elution using an Alltech Alltima C18 (150 x 4.6 mm) column, a mobile phase consisting of ammonium acetate (50 mM; pH 5.0)-ethanol (65:35, v/v), a flow rate of 1.0 ml/min and UV detection at 242 nm. The detection and quantitation limits were 0.03 and 08 microg/ml, respectively, while the linear range of detection was between 0.03 and 255 microg/ml. Comparative determinations of formoterol fumarate in three lots of bulk drugs using the proposed HPLC method and the standard potentiometric titration method of pharmacopoeia show that both methods are equivalent for pure drug substance assay. However, the HPLC method allowed the separation and quantitation of the impurities not achievable with the official methods in the bulk drugs. This study shows that the proposed method is accurate, linear, and sensitive as stability indicating assay method for formoterol fumarate in the bulk drug.

Bronchodilator response to formoterol Turbuhaler in patients with COPD under regular treatment with formoterol Turbuhaler

Formoterol Turbuhaler has been suggested for as-needed use in asthmatic patients. We investigated whether regular treatment with formoterol would modify the dose-response curves to formoterol in patients with partially reversible COPD. In this randomised, double-blind, cross-over study taking place over four non-consecutive days 16 outpatients with moderate to severe COPD, who were under regular treatment with formoterol Turbuhaler (18 microg in two daily doses) from at least 4 months, inhaled a conventional dose of formoterol Turbuhaler 9 microg or placebo. Two hours later, a FEV(1) value was established, following which a dose-response curve to formoterol (4.5 microg/inhalation) or placebo was constructed using four inhalations (1+1+2)--total cumulative delivered dose of 18 microg formoterol--with the following sequences: (1) formoterol pre-treatment + formoterol 18 microg, (2) formoterol pre-treatment + placebo, (3) placebo pre-treatment + formoterol 18 microg, (4) placebo pre-treatment + placebo. Formoterol 9 microg induced significant (P < 0.0001) bronchodilation at 2 h after inhalation (best mean increase in FEV(1): 0.170 L). Afterwards, dose-dependent increases in FEV(1) occurred with formoterol (maximum mean increase from 2-h value with formoterol: 0.072 after formoterol pre-treatment, and 0.201 L after placebo pre-treatment). Both maximum values of bronchodilation after the last inhalation of formoterol were statistically different (P < 0.001) from 2-h levels. These results show that dose-dependent bronchodilatation of formoterol is maintained despite regular treatment.

Bronchodilator effect of an inhaled combination therapy with salmeterol + fluticasone and formoterol + budesonide in patients with COPD

In the present trial, we compared the broncholytic efficacy of the combination therapy with 50 microg salmeterol + 250 microg fluticasone and 12 microg formoterol + 400 microg budesonide, both in a single inhaler device, in 16 patients with moderate-to-severe COPD. The study was performed using a single-blind crossover randomized study. Lung function, pulse oximetry (SpO2) and heart rate were monitored before and 15, 30, 60, 120, 180, 240, 300, 360, 480, 600, and 720 min after bronchodilator inhalation. Both combinations were effective in reducing airflow obstruction. FEV1 AUC(0-12 h) was 2.83 l (95% CI: 2.13-3.54) after salmeterol/fluticasone and 2.57 l (95% CI: 1.97-3.2) after formoterol/budesonide. Formoterol/budesonide elicited the mean maximum improvement in FEV1 above baseline after 120 min (0.29 l; 95% CI: 0.21-0.37) and salmeterol/fluticasone after 300 min (0.32 l; 95% CI: 0.23-0.41). At 720 min, the increase in FEV1 over baseline values was 0.10 l (95% CI: 0.07-0.12) after salmeterol/fluticasone and 0.10 l (95% CI: 0.07-0.13) after formoterol/budesonide. The mean peak increase in heart rate occurred 300 min after formoterol/budesonide (1.5 b/min; 95% CI--2.3 to 5.3) and 360 min after salmeterol/fluticasone (2.6 b/min; 95% CI--1.9 to 7.0). SpO2 did not change. All differences between salmeterol/fluticasone and formoterol/budesonide were not significant (P > 0.05) except those in FEV1 at 120 and 360 min. The results indicate that an inhaled combination therapy with a long-acting beta2-agonist and an inhaled corticosteroid appears to be effective in improving airway limitation after acute administration in patients suffering from COPD.

Management of insomnia in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a common medical disorder, which causes considerable morbidity and mortality. Given the chronic and symptomatic nature of the disease, the patient is often seen in the physician's office with complaints of dyspnea. However, more than 50% of COPD patients also have sleep complaints characterised by longer latency to falling asleep, more frequent arousals and awakenings, and/or generalised insomnia. Sleep disturbance tends to be more severe with advancing disease and substantially reduces the COPD patients' quality of life. In approaching the COPD patient who complains of insomnia it is important to take a complete sleep history. Having characterised the degree and duration of the problem, medical management of the underlying COPD must first optimise oxygen saturation while minimising the effects of many of the medications used for COPD. While aerosol therapies may be systemically absorbed and contribute to sleep disruption, anticholinergics, such as ipratropium bromide, are the least likely to do so and indeed have been shown to improve sleep quality in this population. Many of the traditional sedatives and hypnotics have been used in the COPD population including benzodiazepines, imidazopyridines, pyrazolopyrimidines and, less commonly, antidepressants and phenothiazines. Clinical trials support the role of numerous agents in treating insomnia in this population but do not always provide reassurance that these therapies can be used safely, particularly in the patient with severe COPD with hypercarbia. Benzodiazepines are among the most commonly employed agents, but case reports and series continue to describe adverse pulmonary events. Although the newer pyridine derivatives also have the potential to worsen pulmonary function, they appear less likely to do so. Data to date are limited with the tricyclic antidepressants and phenothiazines, although they appear to be very well tolerated from a respiratory point of view. Since sleep disturbances are often long-standing and associated with maladaptive behaviours towards sleep, cognitive/behavioural approaches are often useful and are more effective in the long-term than are hypnotics. When prescription of a sedative is to be made, extra caution is required for those patients at increased risk of adverse respiratory effects, such as those with advanced disease and hypercarbia in whom pharmacological therapy is often best avoided. Selection of the various options will depend upon the degree of underlying disease and the patient's specific complaints of insomnia. Finally, it is important to remember that while most hypnotics work in an acute setting, the long-term management will require an integrated approach.

Effects of formoterol (Oxis Turbuhaler) and ipratropium on exercise capacity in patients with COPD

Although long-acting inhaled beta 2-agonists improve various outcome measures in COPD, no double-blind study has yet shown a significant effect of these drugs on exercise capacity. In a randomized, double-blind, placebo-controlled, crossover study, patients received formoterol (4, 5, 9, or 18 micrograms b.i.d. via Turbuhaler), ipratropium bromide (80 micrograms t.i.d. via pMDI with spacer), or placebo for 1 week. Main endpoint was time to exhaustion (TTE) in an incremental cycle ergometer test. Secondary endpoints were Borg dyspnoea score during exercise, lung function, and adverse events. Thirty-four patients with COPD were included, mean age 64.8 years, FEV1 55.6% predicted, reversibility 6.1% predicted. All doses of formoterol, and ipratropium significantly improved TTE, FEV1, FEF25-75%, FRC, IVC, RV and sGAW compared with placebo. A negative dose-response relationship was observed with formoterol. Ipratropium increased time to exhaustion more compared with formoterol, 18 micrograms, but not with formoterol, 4.5 and 9 micrograms. No changes in Borg score were found. There was no difference in the adverse event profile between treatments. In conclusion, 1 week of treatment with formoterol and ipratropium significantly improved exercise capacity and lung function compared with placebo. However, a negative dose-response relation for formoterol was unexpected and needs further investigation.

Addition of an extra dose of salmeterol Diskus to conventional dose of salmeterol Diskus in patients with COPD

Patients experiencing dyspnoea can request an additional dose of salmeterol during the dose interval for the control of their symptoms, although under treatment with salmeterol. In this study we have explored the effects on respiratory function of an additive dose of salmeterol Diskus in 15 chronic obstructive pulmonary disease (COPD) patients in regular treatment with a conventional dose of 50 microg salmeterol. On two different days, patients inhaled 50 microg Diskus. After 240 min, they inhaled additional 50 microg salmeterol Diskus (salmeterol arm) or placebo Diskus (placebo arm). Lung function was controlled before first drug administration and 0.5, 1, 2, 3, 4, 4.5, 6, 8, 10, and 12 h thereafter. The mean (95% CI) peak increase in FEV1 from baseline was reached after 4 h in the salmeterol arm (0.174 L; 0.144-0204) and after 5 h (0.141 L; 0.115-0.168) inthe placebo arm; after 12 h, the mean (95% Cl) increase in FEV1 from basal values was still 0.149 L (0.119-0.179) in salmeterol arm, but only 0.041 L (0.017-0.064) in placebo arm. The mean (95% CI) FEV1 AUC0-12h for all patients were 2.01 (1.72-2.30) L when salmeterol was added and 1.30 (1.03-1.58) L when placebo was inhaled. The difference (mean; 95% CI) between the FEV1 AUC0-12h of the two arms (0.71 L; 0.47-0.95) was statistically significant (P<0.0001), although the difference (mean; 95% CI) between the FEV1 AUC0-4h of the two treatments (0.08 L; -0.02-0.18) was notstatistically significant (P=0.126). The addition of an extra dose of salmeterol did not significantly increase the heart rate or decrease the SpO2. This study suggests that the addition of an extra dose of salmeterol does not give room for further increase in peak FEV1, but the effect of adding salmeterol to salmeterol is largely additive when considering the duration of action and safe.

Comparison of the efficacy, tolerability, and safety of formoterol dry powder and oral, slow-release theophylline in the treatment of COPD

STUDY OBJECTIVE

To compare the efficacy, tolerability, and safety of therapy with formoterol and oral slow-release theophylline (THEO) in patients with COPD.

DESIGN

A randomized, parallel-group study, with double-blind arms for formoterol and placebo (PL) and an open arm for oral slow-release THEO administered in individual doses on the basis of plasma concentrations.

SETTING

Eighty-one centers worldwide.

PATIENTS

Eight hundred fifty-four patients with symptomatic COPD.

INTERVENTION

Comparison of twice-daily inhaled formoterol dry powder (12 or 24 microg), PL, and THEO (individualized doses) over 12 months.

MEASUREMENTS AND RESULTS

Compared to PL, doses of formoterol and THEO both significantly improved the area under the curve for FEV(1) measured over a period of 12 h following the morning dose of study medication at 3 and 12 months (p < 0.001 for all comparisons). Therapy with formoterol, 12 microg, was significantly more effective than that with THEO (p < or = 0.026). Formoterol significantly reduced the percentage of "bad days" (i.e., days with at least two individual symptom scores > or = 2 and/or a reduction in peak expiratory flow from a baseline of > 20%; p < or = 0.035 vs. PL and THEO), and the use of salbutamol rescue medication (p < or = 0.003 vs PL) over the whole treatment period, while the effect of THEO was similar to that of PL. Therapy with formoterol and THEO was more effective than PL at improving quality of life for > 12 months (p < or = 0.030). Treatment-related adverse events and discontinuations were more frequent among patients receiving THEO than among those receiving formoterol.

CONCLUSIONS

Long-term treatment with inhaled formoterol dry powder is more effective and better tolerated than treatment with therapeutically appropriate doses of oral slow-release THEO in symptomatic patients with COPD.

Recent advances in diagnosis and management of chronic bronchitis and emphysema

Chronic obstructive pulmonary disease is a progressive inflammatory disease of the airways and lung parenchyma. Expiratory airflow limitation is the hallmark of chronic obstructive pulmonary disease. It is a significant cause of morbidity and mortality in the United States and worldwide and results in a large consumption of health care resources. Unfortunately, despite efforts to curb this disease, its prevalence is increasing. The diagnosis is usually made when the patient complains of dyspnea on exertion; by this time, irreversible structural damage to the lung has already occurred. Given the nonspecific symptoms of the disease and the inability to effectively treat and reverse the damage, it is essential to diagnose the disease in its early stages and take the necessary preventive measures, thus avoiding disability or death. This review summarizes the latest developments in the diagnosis and management of chronic obstructive pulmonary disease. The first half of the review discusses functional, radiographic, biochemical, and cellular/histopathologic issues in the diagnosis of chronic obstructive pulmonary disease. The second half focuses on the current pharmacologic and nonpharmacologic advances in chronic obstructive pulmonary disease, including the role of respiratory support and surgical treatment. Based on the research on the cellular mechanisms of chronic obstructive pulmonary disease, the review also makes a reference to novel and experimental therapies for chronic obstructive pulmonary disease.

Inhaled formoterol dry powder versus ipratropium bromide in chronic obstructive pulmonary disease

We compared the effectiveness of inhaled formoterol with that of ipratropium in the treatment of chronic obstructive pulmonary disease (COPD). After a 2-wk run-in period, 780 patients with COPD were randomized to receive for 12 wk formoterol dry powder 12 or 24 microg twice daily, ipratropium bromide 40 microg four times daily, or placebo in a multicenter, double-blind, parallel-group study. The primary efficacy variable was the area under the curve for forced expiratory volume in 1 s (FEV(1)) measured over 12 h after 12 wk of treatment. Secondary variables included diary symptoms and quality of life. Both doses of formoterol and ipratropium significantly increased the area under the curve for FEV(1) in comparison with placebo (all p < 0.001). Both doses of formoterol were also significantly superior to ipratropium (all p < 0.025). Compared with placebo, both doses of formoterol significantly improved symptoms (all p < or = 0.007) and quality of life (p < 0.01 for total scores) whereas ipratropium did not show significant effects (all p > or = 0.3). All study treatments exhibited a similar safety profile. We conclude that formoterol is more effective than ipratropium bromide in the treatment of COPD, as the efficacy of ipratropium on airflow obstruction does not translate into a clinical benefit that patients can perceive.

Onset of action of single doses of formoterol administered via Turbuhaler in patients with stable COPD

We studied 16 patients with stable COPD in a double blind, double dummy, placebo-controlled, within patient study to see if formoterol could be used as a rescue drug. We compared the of onset of bronchodilation obtained with formoterol 12 microg (metered dose corresponding to 9 microg delivered dose) and formoterol 24 microg (metered dose corresponding to 18 microg delivered dose), both delivered via Turbuhaler, with that of salbutamol 400 microg and salbutamol 800 microg delivered via pressurized metered-dose inhaler (pMDI). Patients inhaled single doses of placebo, formoterol and salbutamol on five separate days. FEV1 was measured in baseline condition and 3, 6, 9, 12, 15, 18, 21, 24, 30, 40, 50, and 60 min after inhalation of each treatment. We examined two separate criteria for deciding if a response was greater than that expected by a random variation of the measurement: (1) a rise in FEV1 of at least 15% from the baseline value; (2) an absolute increase in FEV1 of at least 200 ml. Formoterol 12 microg (15.2 min; 95% CI 9.5-21.0) and formoterol 24 microg (15.1 min; 95% CI 8.9-21.2) caused a rise in FEV1 of at least 15% from the baseline value almost rapidly as salbutamol 400 microg (13.6 min; 95% CI 7.1-20.1) and salbutamol 800 microg (14.5 min; 95% CI 7.1-21.9). No significant difference (P=0.982) in onset of action was seen between the four active treatments. According to Criterion 2, the mean time to 200 ml increase in FEV1 was 11.1 min (95% CI: 7.0-15.2) after salbutamol 400 microg, 13.0 min (95% CI: 7.9-18.1) after salbutamol 800 microg, 14.7 min (95% CI: 7.1-22.4) after formoterol 12 microg, and 12.7 min (95% CI: 7.4-18.0) after formoterol 24 microg. Again, there was no significant difference (P= 0.817) between the four active treatments. Formoterol Turbuhaler 12 microg and 24 microg caused bronchodilation as rapidly as salbutamol 400 microg and 800 microg given via pMDI.