The role of combination therapy with corticosteroids and long-acting ��2-agonists in the prevention of exacerbations in COPD

Acute exacerbations of COPD can complicate the course of the disease in patients with severe airway obstruction. Reduction of exacerbations is an important clinical outcome in evaluating new therapies in COPD. Combination therapies with long-acting β-agonists and inhaled corticosteroids have now been approved for use. Three 1-year randomized clinical trials, which studied the effect of combining a long-acting β₂-agonist with an inhaled corticosteroid in COPD, documented that exacerbation frequency was lower with therapy than placebo. Combination therapy had a similar effect to its monocomponents in the trial evaluating salmeterol/fluticasone combination. However, when patients with more severe COPD were studied using a combination of budesonide and formoterol, a clear improvement was seen in the overall exacerbation rates compared with the use of a long-acting β₂-agonist alone.     

Efficacy and safety of formoterol for the treatment of chronic obstructive pulmonary disease

Formoterol is a selective long-acting beta2-adrenergic receptor agonist (LABA) that provides significant and sustained bronchodilatory effect for up to 12h following a single dose. The onset of effect is significantly faster with formoterol compared with an alternative LABA, salmeterol, although both have a similar duration of action. The overall efficacy of formoterol in improving lung function and controlling symptoms of chronic obstructive pulmonary disease (COPD) is comparable to that of salmeterol and potentially superior to that of ipratropium or theophylline. Formoterol provides additional benefit when administered in combination with other bronchodilators or inhaled corticosteroids. In clinical studies, formoterol was well tolerated and had an adverse-event profile similar to that of other beta2-adrenergic receptor agonists. Formoterol is a rapidly acting, well-tolerated, effective beta2-adrenergic receptor agonist that can be regularly used as a long-acting bronchodilator for patients with moderate to severe COPD, as per recommendations of the current treatment guidelines.     

The Long and Short of β2-agonists

For patients whose asthma is not adequately controlled with inhaled corticosteroid (ICS) therapy alone, increasing the dose of ICS or the addition of a long-acting β₂-agonist is recommended. Greater improvements in lung function are achieved with the addition of a long-acting β₂-agonist to ICS therapy, rather than doubling the dose of ICS. Formoterol and salmeterol have a similarly long duration of effect (up to 12 h). However, as a result of their different chemical structures, there are marked pharmacological differences in the mechanism of action which affect their speeds of onset. These differences amount to a more rapid onset of effect for formoterol compared with salmeterol. Long-acting β₂-agonists appear to be well tolerated at elevated doses. These two features (tolerability at high doses and rapid onset of effect) support the use of formoterol as a reliever medication in addition to use in maintenance therapy. The long-acting β₂-agonists can be considered as beneficial additions to ICS therapy for the management of moderate-to-severe asthma.     

Inhaled formoterol versus ipratropium bromide in chronic obstructive pulmonary disease

BACKGROUND: Short-acting anticholinergic bronchodilator, ipratropium bromide has been recommended as first-line drug in chronic obstructive pulmonary disease (COPD). More recently, long acting beta2-agonist (LABA) bronchodilators such as formoterol have been shown to be useful in COPD. Limited information is available on the relative efficacy of these two drugs in COPD. METHODOLOGY: A randomised, double-blind, cross-over, placebo-controlled study was carried out. Forty-four stable patients with COPD received single doses of formoterol (12 microg), ipratropium bromide (40 microg) or placebo, administered through a metered-dose inhaler on three consecutive days in a random order. Spirometry, static lung volumes, pulse rate and blood pressure, and assessment of sensation of dyspnoea at rest using a visual analog scale (Borg Scale) were recorded at baseline. Subsequently, these were repeated for assessment of response: spirometry at 5, 30 and 60 minutes and static lung volumes, pulse rate, blood pressure and dyspnoea measurement at 60 minute. RESULTS: Formoterol resulted in greater immediate improvement in lung function, with the change in FEV1 at 5 min being greater than that observed with ipratropium. The changes in static lung volumes were similar between the two but superior to placebo. Both the drugs reduced dyspnoea. Formoterol produced a significantly greater increase in heart rate and systolic blood pressure as compared to ipratropium, although the magnitude of these changes was small and clinically unimportant. CONCLUSIONS: Single therapeutic doses of formoterol and ipratropium bromide are equally effective in improving lung function and reducing dyspnoea. However, formoterol appears to be a better bronchodilator producing a faster improvement in lung function.     

Formoterol

Abstract

Inhaled formoterol is a long-acting selective β₂-adrenoceptor agonist, with an onset of action of 5 minutes postdose and a bronchodilator effect that lasts for at least 12 hours.Statistically significant and clinically relevant (> 120ml) improvements in lung function [assessed using standardized/normalized area under the forced expiratory volume in 1 second (FEV₁) versus time curve (AUC FEV₁)] were observed with inhaled formoterol 12μg twice daily (the approved dosage in the US) compared with placebo in 12-week and 12-month, randomized, double-blind trials in patients with chronic obstructive pulmonary disease (COPD).The bronchodilator efficacy of formoterol 12μg twice daily was greater than that of oral slow-release theophylline (individualized dosages) in a 12-month trial or inhaled ipratropium bromide 40μg four times daily in a 12-week trial. Improvement in AUC FEV₁ with formoterol, but not theophylline, compared with placebo was observed in patients with irreversible or poorly-reversible airflow obstruction. Formoterol also significantly improved health-related quality of life compared with ipratropium bromide or placebo and significantly reduced symptoms compared with placebo. Combination therapy with formoterol 12μg twice daily plus ipratropium bromide 40μg four times daily was significantly more effective than albuterol (salbutamol) 200μg four times daily plus the same dosage of ipratropium bromide in a 3-week, randomized, double-blind, double-dummy, crossover trial.Inhaled formoterol was well tolerated in clinical trials. The incidence of investigator-determined drug-related adverse events with inhaled formoterol 12μg twice daily was similar to that with placebo and inhaled ipratropium bromide 40μg four times daily but lower than that with oral slow-release theophylline (individualized dosages). Importantly, there were no significant differences between formoterol and placebo or comparator drugs in cardiovascular adverse events in patients with COPD and corrected QT interval values within the normal range.In conclusion, inhaled formoterol improved lung function and health-related quality of life and reduced symptoms relative to placebo in clinical trials in patients with COPD. The drug had greater bronchodilator efficacy than oral slow-release theophylline or inhaled ipratropium bromide and showed efficacy in combination with ipratropium bromide. The adverse events profile (including cardiovascular adverse events) with formoterol was similar to that with placebo. Thus, inhaled formoterol may be considered as a first-line option for the management of bronchoconstriction in patients with COPD who require regular bronchodilator therapy for the management of symptoms.

Pharmacodynamic Properties

Inhaled formoterol is a long-acting selective β₂-adrenoceptor agonist (β₂-agonist); it has a rapid onset of action (5 minutes in single- and multiple-dose studies) and, like salmeterol, maintains a bronchodilator effect for at least 12 hours. The onset of postdose bronchodilator action was faster with formoterol 12μg than with salmeterol 100μg in a double-blind, randomized, placebo-controlled trial.Formoterol 6 to 24μg improved forced expiratory volume in 1 second (FEV₁) compared with baseline and placebo in single-dose crossover trials in patients with chronic obstructive pulmonary disease (COPD), and was at least as effective as salmeterol 50 or 100μg or albuterol (salbutamol) 400μg at improving FEV₁. Mean peak FEV₁ was reached 1 hour after inhalation of formoterol 12μg; values for this parameter were 1 hour after albuterol 200μg, and 2 to 5 hours after salmeterol 50μg.Formoterol 4.5 to 18μg twice daily for 1 week prolonged the time to exhaustion on a bicycle ergometer test compared with placebo; results were similar to those for ipratropium bromide 80μg three times daily.All β₂-agonists have the potential to increase heart rate and plasma glucose concentrations, and to decrease plasma potassium concentrations, through effects on extrapulmonary β₂ receptors. Dose-dependent increases in heart rate, corrected QT (QTc) interval and plasma glucose concentrations, and dose-dependent decreases in plasma potassium concentrations, were observed with inhaled formoterol 24 to 96μg or salmeterol 100 to 400μg in a double-blind, placebo-controlled, crossover trial in 16 healthy volunteers. In patients with COPD, pre-existing mild to moderate cardiac arrhythmias and hypoxemia [PaO₂ (arterial oxygen pressure) <60mm Hg], formoterol 12μg had similar systemic effects to salmeterol 50μg. Complex ventricular arrhythmias were observed in formoterol 12 and 24μg recipients, but not in salmeterol 50μg or placebo recipients.

Pharmacokinetic Properties

The maximum plasma concentration (92 ng/L) of formoterol was reached within 5 minutes of inhalation of a single supraoptimal dose (120μg) in 12 healthy volunteers. Urinary excretion data suggest that absorption was linear with inhaled formoterol 12 to 96μg in ten healthy volunteers. In vitro plasma protein binding of formoterol was 61 to 64% at concentrations 0.1 to 100 μg/L.Mean plasma concentrations of the drug at 10 minutes to 6 hours postinhalation were 4.0 to 8.8 ng/L and 8.0 to 17.3 ng/L, respectively, after multiple doses of formoterol 12 or 24μg administered twice daily for 12 weeks in patients with COPD, with some evidence of accumulation of formoterol in the plasma (accumulation index 1.19 to 1.38).Formoterol is metabolized primarily in the liver by four cytochrome P450 (CYP) isoenzymes (CYP2D6, CYP2C19, CYP2C9 and CYP2A6). These enzymes were not inhibited by the drug at therapeutic concentrations. Following inhalation of formoterol 12 or 24μg by 18 patients with COPD, 7% of the total dose was excreted in the urine as unchanged drug and 6 to 9% of the total dose was eliminated as direct conjugates of formoterol. The mean terminal elimination half-life was determined to be 10 hours (based on plasma concentrations) following inhalation of single-dose formoterol 120μg by 12 healthy volunteers.Currently, there are no pharmacokinetic data for the use of formoterol in patients with hepatic or renal impairment or in elderly individuals.

Therapeutic Efficacy

Inhaled formoterol has been evaluated as monotherapy or combination therapy for the management of patients with COPD. In clinical trials, COPD was diagnosed using the American Thoracic Society guidelines.The bronchodilator effect [measured as normalized area under the FEV₁ versus time curve (AUC FEV₁)] with formoterol 12μg twice daily (n = 194) was significantly greater than that with ipratropium bromide 40μg four times daily (n = 194; p = 0.001) or placebo (n = 200; p < 0.001) in a randomized, double-blind, 12-week trial in patients with COPD. Significant improvements were also observed in mean morning premedication peak expiratory flow (PEF; p < 0.001) and health-related quality of life [all three subsections of the St. George’s Respiratory Questionnaire (SGRQ); p ≤ 0.036], and significant reductions were reported for the use of rescue medication (p ≤ 0.014) and the percentage of ‘bad days’ (days with at least two individual symptom scores of ≥2 and/or a reduction in PEF from baseline of >20%; p < 0.001) in formoterol compared with ipratropium bromide recipients. The differences in health-related quality of life between the two treatments were clinically relevant (exceeding 4 points) for the Activity and the Impacts domains of the SGRQ.Compared with oral slow-release theophylline (individualized dosages targeted at plasma concentrations of 8 to 20 mg/L), formoterol 12μg twice daily significantly increased standardized AUC_12h FEV₁ (primary end-point; p = 0.026) and mean morning premedication PEF (p ≤ 0.020) and reduced the percentage of ‘bad days’ (p ≤ 0.035) in a randomized, double-blind (with the exception of the theophylline arm), 12-month trial. A subgroup analysis in this trial indicated that at 3 (p = 0.007) and 12 months (p = 0.002), formoterol (n = 118), but not oral slow-release theophylline (n = 105), produced significant bronchodilation compared with placebo (n = 117) in patients with irreversible or poorly-reversible airflow obstruction (i.e. patients whose FEV₁ values increased <15% after receiving albuterol). Both formoterol (p ≤ 0.026) and oral slow-release theophylline (p ≤ 0.013) were significantly more effective than placebo at managing COPD during the night (measured as morning premedication FEV₁).In these two monotherapy trials, inhaled formoterol 24μg twice daily did not provide any additional benefit over the 12μg twice daily dosage in patients with COPD.The combined efficacy of inhaled formoterol 12μg twice daily plus inhaled ipratropium bromide 40μg four times daily for 3 weeks has been compared with that of albuterol 200μg four times daily for 3 weeks via a pressurized metered-dose inhaler plus inhaled ipratropium bromide 40μg four times daily in a randomized, double-blind, double-dummy, crossover trial in 172 patients with COPD. Formoterol combination therapy was significantly more effective than albuterol combination therapy at increasing mean morning premedication PEF (primary endpoint; p = 0.0003). Combination therapy with formoterol was also more effective according to secondary endpoints, significantly increasing postmedication FEV₁ to 6 hours (p< 0.0001), peak postmedication FEV₁ (p < 0.0001) and AUC FEV₁ (p < 0.0001) and improving symptoms of COPD (measured as mean total symptoms score, p = 0.0042) and the SGRQ symptoms score (p = 0.0408) relative to albuterol combination therapy.

Tolerability

Inhaled formoterol was well tolerated in clinical trials in patients with COPD. The percentage of patients experiencing at least one adverse event with inhaled formoterol 12μg twice daily was similar to that with placebo, inhaled ipratropium bromide 40μg four times daily or oral slow-release theophylline (individualized dosages targeted at plasma concentrations of the drug of 8 to 20 mg/L) in randomized, double-blind, comparative trials of 12 weeks’ and 12 months’ duration. Viral infection, exacerbation of COPD, bronchitis, upper respiratory tract infection, dyspnea and headache were the most commonly reported adverse events (i.e. occurring in >5% of formoterol 12μg twice daily recipients); however, the incidence of these events was not significantly different compared with oral slow-release theophylline or placebo.Drug-related adverse events, serious adverse events and events leading to withdrawal from the study occurred with a similar incidence with inhaled formoterol, placebo or ipratropium bromide. In contrast, drug-related adverse events and withdrawal because of adverse events occurred with a higher incidence in patients receiving oral slow-release theophylline in the 12-month trial.There were no significant differences in the incidence of cardiovascular adverse events with inhaled formoterol (0.5% of patients) compared with inhaled placebo (2.5%) or ipratropium bromide (2.6%) after 12 weeks’ treatment or in the incidence of serious cardiovascular adverse events with inhaled formoterol (2.4% of patients) compared with placebo (0.9%) or oral slow-release theophylline (2.4%) after 12 months’ treatment in patients with COPD and QTc interval values within the normal range; heart rate and rhythm disorders were infrequent. The incidences of QTc interval prolongation (>0.46s), ECG abnormalities or clinically relevant changes in serum potassium or fasting plasma glucose concentrations were similar with inhaled formoterol 12μg twice daily compared with placebo, inhaled ipratropium bromide or oral slow-release theophylline in clinical trials.

Dosage and Administration

Formoterol, inhaled orally using an Aerolizer?1 inhaler, is indicated in the US for the long-term maintenance treatment of bronchoconstriction associated with COPD (including chronic bronchitis and emphysema). The recommended dosage of formoterol in this patient group is 12μg twice daily approximately 12 hours apart; the total daily dose should not exceed 24μg.Formoterol should be used with caution in patients with cardiovascular disorders (especially coronary insufficiency, cardiac arrhythmias or hypertension), convulsive disorders or thyrotoxicosis, or hypersensitivity to sympathomimetic amines. Extreme caution is advised if formoterol is used concomitantly with monoamine oxidase inhibitors, tricyclic antidepressants or drugs that are known to prolong the QTc interval, and caution is recommended with the concomitant use of formoterol and non-potassium-sparing diuretics.

     

Comparison and optimal use of fixed combinations in the management of COPD

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. Indications for the use of long-acting β₂-agonists (LABAs) and inhaled corticosteroids (ICS) in patients with COPD are described in the various international guidelines, but no special recommendations are made concerning the use of combination inhalers containing a LABA as well as an ICS. To determine the place of combination inhalers in the treatment of COPD we reviewed recent literature concerning this subject. On molecular level ICS/LABA combination therapy has anti-inflammatory properties which cannot be attributed to ICS alone. All clinical studies indicate that the two available combinations (salmeterol/fluticasone and formoterol/budesonide) significantly reduce exacerbation rate of moderate/severe exacerbations when compared with placebo. Some studies also showed a significant reduction in exacerbation rate compared with LABA monotherapy, but not compared with ICS monotherapy. From the patient’s perspective, ICS/LABA combination inhalers are the first choice when both need to be prescribed, possibly improving patient compliance for ICS. Currently little evidence is available to predict if flexible treatment with LABA/ICS combination inhalers will improve disease control in COPD. Further studies are needed to elucidate the clinical benefit of combination inhalers versus the individual components in different inhalers, and to investigate the clinical benefit of flexible dosing of combination inhalers in patients with COPD.     

Formoterol: a review of its use in chronic obstructive pulmonary disease

Inhaled formoterol is a long-acting selective beta2-adrenoceptor agonist, with an onset of action of 5 minutes postdose and a bronchodilator effect that lasts for at least 12 hours. Statistically significant and clinically relevant (>120 ml) improvements in lung function [assessed using standardized/normalized area under the forced expiratory volume in 1 second (FEV1) versus time curve (AUC FEV1)] were observed with inhaled formoterol 12 microg twice daily (the approved dosage in the US) compared with placebo in 12-week and 12-month, randomized, double-blind trials in patients with chronic obstructive pulmonary disease (COPD). The bronchodilator efficacy of formoterol 12 microg twice daily was greater than that of oral slow-release theophylline (individualized dosages) in a 12-month trial or inhaled ipratropium bromide 40 microg four times daily in a 12-week trial. Improvement in AUC FEV1 with formoterol, but not theophylline, compared with placebo was observed in patients with irreversible or poorly-reversible airflow obstruction. Formoterol also significantly improved health-related quality of life compared with ipratropium bromide or placebo and significantly reduced symptoms compared with placebo. Combination therapy with formoterol 12 microg twice daily plus ipratropium bromide 40 microg four times daily was significantly more effective than albuterol (salbutamol) 200 microg four times daily plus the same dosage of ipratropium bromide in a 3-week, randomized, double-blind, double-dummy, crossover trial. Inhaled formoterol was well tolerated in clinical trials. The incidence of investigator-determined drug-related adverse events with inhaled formoterol 12 microg twice daily was similar to that with placebo and inhaled ipratropium bromide 40 microg four times daily but lower than that with oral slow-release theophylline (individualized dosages). Importantly, there were no significant differences between formoterol and placebo or comparator drugs in cardiovascular adverse events in patients with COPD and corrected QT interval values within the normal range. In conclusion, inhaled formoterol improved lung function and health-related quality of life and reduced symptoms relative to placebo in clinical trials in patients with COPD. The drug had greater bronchodilator efficacy than oral slow-release theophylline or inhaled ipratropium bromide and showed efficacy in combination with ipratropium bromide. The adverse events profile (including cardiovascular adverse events) with formoterol was similar to that with placebo. Thus, inhaled formoterol may be considered as a first-line option for the management of bronchoconstriction in patients with COPD who require regular bronchodilator therapy for the management of symptoms.     

Effects of formoterol and ipratropium bromide in COPD: a 3-month placebo-controlled study.

The aim of this study was to compare the effects of formoterol, ipratropium bromide and a placebo on walking distance, lung function, symptoms and quality of life (QoL) in chronic obstructive pulmonary disease (COPD) patients. A total of 183 patients (mean age 64 yrs, 86 female) with moderate-to-severe nonreversible COPD participated in this randomised, double-blind, parallel-group study. After a 2-week placebo run-in, patients were randomised to formoterol Turbuhaler 18 microg b.i.d. (delivered dose), ipratropium bromide 80 microg t.i.d. via a pressurised metered dose inhaler, or placebo for 12 weeks. Inhaled short-acting beta2-agonists were allowed as relief medication and inhaled glucocorticosteroids were allowed at a constant dose. The primary variable was walking distance in the shuttle walking test (SWT). Baseline mean SWT distance was 325 m, mean forced expiratory volume in one second (FEV1) was 40% predicted. Clinically significant improvements in SWT (>30 m) were seen in 41, 38 and 30% of formoterol, ipratropium and placebo patients, respectively (not significant). Mean increases from run-in were 19, 17 and 5 m in the formoterol, ipratropium and placebo groups, respectively. Both active treatments significantly improved FEV1, forced vital capacity, peak expiratory flow and daytime dyspnoea score compared with placebo. Formoterol reduced relief medication use compared with placebo. Neither active treatment improved QoL. Formoterol and ipratropium improved airway function and symptoms, without significant improvements in the shuttle walking test.     

Budesonide�Cformoterol (inhalation powder) in the treatment of COPD

The budesonide–formoterol dry powder inhaler (Symbicort^® Turbuhaler^® 160/4.5–640/18 μg/day) contains the long-acting β₂-adrenoreceptor agonist formoterol and the inhaled corticosteroid budesonide. Two large, 12-month trials examined the effect of budesonide–formoterol 160/4.5 μg twice daily in COPD patients who met these criteria. The studies were identical, except one in which the patients had received oral prednisolone 30 mg/day and had inhaled formoterol 4.5 μg twice daily for 2 weeks before randomization. In terms of the FEV₁, budesonide–formoterol produced an effect greater than that of both budesonide alone and formoterol alone reported in previous studies. The combination was generally more effective than either of the components in terms of peak expiratory flow, symptoms, and exacerbations. These advantages of the combination over those of either budesonide alone or formoterol alone were quite consistent. Improving lung function and decreasing symptoms significantly, budesonide–formoterol combination therapy provides significant clinical improvements in COPD, despite the limited reversibility of impaired lung function in the disease.     

Bronchodilators in COPD: Impact of ��-agonists and anticholinergics on severe exacerbations and mortality

This review summarizes the long-term clinical outcomes associated with β-agonist and anticholinergic bronchodilator use in patients with chronic obstructive pulmonary disease (COPD). Pooled data from randomized placebo-controlled trials of at least three months duration were used to evaluate the risk for COPD hospitalizations, respiratory mortality, and total mortality. The results show that anticholinergic use is associated with a 30% reduction in COPD hospitalizations, a 70% reduction in respiratory mortality, and without a significant effect on total mortality. In contrast, β-agonist use had no effect on COPD hospitalizations and was associated with a two-fold increased risk for respiratory death compared with placebo. When the two bronchodilators were directly compared with each other, β-agonists were associated with a two-fold increased risk for COPD hospitalization and a five-fold increased risk for total mortality compared with anticholinergics. When β-agonists were added to either anticholinergic use or inhaled corticosteroid use alone, there was no significant improvement in any long-term clinical outcome. These results indicate that anticholinergics should be the bronchodilator of choice in COPD, while β-agonists may be associated with poorer disease control.     

Pharmacological treatment of chronic obstructive pulmonary disease

None of the drugs currently available for chronic obstructive pulmonary disease (COPD) are able to reduce the progressive decline in lung function which is the hallmark of this disease. Smoking cessation is the only intervention that has proved effective. The current pharmacological treatment of COPD is symptomatic and is mainly based on bronchodilators, such as selective β₂-adrenergic agonists (short- and long-acting), anticholinergics, theophylline, or a combination of these drugs. Glucocorticoids are not generally recommended for patients with stable mild to moderate COPD due to their lack of efficacy, side effects, and high costs. However, glucocorticoids are recommended for severe COPD and frequent exacerbations of COPD. New pharmacological strategies for COPD need to be developed because the current treatment is inadequate.     

Long-term studies on long-acting sympathomimetics

Long-term treatment studies with formoterol and salmeterol show that these inhaled long-actingβ ₂-agonists compared to availableβ ₂-agonists produce better bronchodilation, decrease the need for additional doses, decrease asthma symptoms, and are strongly preferred by the patients. Development of tolerance has not been found. One case history indicates that these effective bronchodilators might mask deterioration of asthma.     

The role of long-acting bronchodilators in the management of stable COPD

Bronchodilators form the foundation of symptomatic treatment of COPD. Several long-acting bronchodilators are now available for use in COPD, but publications of large-scale studies of their efficacy have, for the most part, postdated the publication of major clinical guidelines. This article provides a critical review of large (> or =50 patients), double-blind, clinical trials of three long-acting bronchodilators in COPD (the once-daily anticholinergic tiotropium, and the twice-daily beta(2)-agonists formoterol and salmeterol) within the context of the objectives of treatment defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. Fourteen published studies were identified, of which 12 studies were published since the release of the GOLD guidelines. All three long-acting bronchodilators were found to effectively improve lung function; however, they differed in their effects on outcomes other than bronchodilation, with salmeterol demonstrating inconsistent efficacy compared with placebo in preventing exacerbations and improving health status, and only tiotropium demonstrating consistent superiority to the short-acting bronchodilator ipratropium. Based on this review, a treatment algorithm for the introduction of long-acting bronchodilators to patients with COPD is proposed, which includes the use of long-acting bronchodilators early in the treatment algorithm.     

Salmeterol/fluticasone combination in the treatment of COPD

Clinical trials of a combination therapy of an inhaled corticosteroid, fluticasone propionate (FP), with a long-acting β₂-agonist, salmeterol (Sal), have demonstrated a greater improvement in lung function and in quality of life measures after the combination compared with either component of alone. In a subanalysis of the data of the TRISTAN study, Sal/FP reduced exacerbation rates in COPD patients with a baseline FEV₁<50% of predicted. A combination therapy of budesonide and formoterol improved quality of life and FEV₁, and reduced exacerbations better than either component alone. In studies of FP or of Sal/FP in COPD, there was a reduction in all-cause mortality by 25% relative to placebo. Sal/FP has anti-inflammatory effects in COPD airways. FP inhibits markers of systemic inflammation, and it is not known whether Sal/FP has an advantage over FP alone. While long-acting β₂-agonists such as Sal can be recommended for treatment of moderate COPD, addition of inhaled steroid therapy such as FP should be considered in more severe disease.     

Effect of add-on therapy of tiotropium in COPD treated with theophylline

Background

Although combination therapy with bronchodilators is recommended for chronic obstructive pulmonary disease (COPD), there is insufficient evidence for the efficacy of some combinations of long-acting bronchodilators.

Objective

We investigated the effects of a combination therapy with tiotropium and theophylline in COPD patients.

Methods

In a 12-week, open-labeled, parallel-group randomized study, pulmonary functions and dyspnea scores were compared between the combination and theophylline alone therapy at baseline, and 4 and 8 weeks after randomization in COPD.

Results

Sixty-one COPD patients completed the trial (31 combination therapy, 30 theophylline alone; mean age 70 years; 58 males; mean dyspnea score 2.0 and forced expiratory volume in one second (FEV₁) 1.5 L [62.5% predicted]). FEV₁ in the combination group, but not in the theophylline alone, was significantly increased at 4 (1.56 ± 0.13 L, p < 0.001) and 8 weeks (1.60 ± 0.13 L, p < 0.001) from the baseline (1.40 ± 0.12 L). In the combination group, but not the theophylline alone group, the dyspnea score was significantly improved after 4 (p < 0.01) and 8 weeks (p < 0.05) compared with baseline. In 17 patients who did not receive theophylline at screening, treatment with 4 or 8 weeks of theophylline alone did not improve dyspnea score or FEV₁.

Conclusion

Addition of tiotropium therapy to theophylline treatment can improve dyspnea and pulmonary function in COPD. Although this study did not assess whether there was any benefit of adding theophylline to patients treated with tiotropium, tiotropium can be a useful addition in COPD already treated with theophylline.     

Role of indacaterol,a once-daily bronchodilator,in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by progressive airflow obstruction that can lead to lung destruction and dyspnea. Although there has been a slight reduction in mortality in recent decades, COPD is still a serious health problem that has enormous costs and utilizes significant medical resources. There have been a number of pharmacologic interventions that have been developed for the treatment of COPD. Current guidelines recommend the use of long-acting bronchodilators for the treatment of moderate and severe stage COPD, since they have been shown to improve lung function, respiratory symptoms, and quality of life. Indacaterol is a once-daily beta2-agonist (β2-agonist) delivered by a single-dose dry powder inhaler used for the treatment of COPD. It is currently approved at a dose of 75 μg in the United States and a dose of 150 μg with a maximal dose of 300 μg in Europe and other countries. Several studies show that indacaterol was statistically superior to both long-acting β2-agonist, formoterol and salmeterol, as well as, noninferior to tiotropium. Indacaterol is generally well tolerated and has a good safety profile. Other studies show that there is an additive bronchodilator response with the addition of indacaterol to tiotropium, which would provide a once-daily treatment option for patient with moderate to severe COPD. This review discusses the pharmacokinetic, comparative efficacy and safety data for indacaterol.KEYWORDS : Indacaterol, chronic obstructive pulmonary disease (COPD), long-acting beta2-agonist (β2-agonist), tiotropium, salmeterol, formoterol, bronchodilator     

The severity of airways obstruction as a determinant of treatment response in COPD

Guidelines recommend that patients with COPD are stratified arbitrarily by baseline severity (FEV₁) to decide when to initiate combination treatment with a long-acting β₂-agonist and an inhaled corticosteroid. Assessment of baseline FEV₁ as a continuous variable may provide a more reliable prediction of treatment effects. Patients from a 1-year, parallel-group, randomized controlled trial comparing 50 μg salmeterol (Sal), 500 μg fluticasone propionate (FP), the combination (Sal/FP) and placebo, (bid), were categorized post hoc into FEV₁ <50% and FEV₁ ≥50% predicted subgroups (n=949/513 respectively). Treatment effects on clinical outcomes – lung function, exacerbations, health status, diary card symptoms, and adverse events – were investigated. Treatment responses based on a pre-specified analysis explored treatment differences by severity as a continuous variable. Lung function improved with active treatment irrespective of FEV₁; Sal/FP had greatest effect. This improvement appeared additive in milder disease; synergistic in severe disease. Active therapy significantly reduced exacerbation rate in patients with FEV₁ <50% predicted, not in milder disease. Health status and breathlessness improved with Sal/FP irrespective of baseline FEV₁; adverse events were similar across subgroups. The spirometric response to Sal/FP varied with baseline FEV₁, and clinical benefits were not restricted to patients with severe disease. These data have implications for COPD management decisions, suggesting that arbitrary stratifications of baseline severity are not necessarily indicative of treatment efficacy and that the benefits of assessing baseline severity as a continuous variable should be assessed in future trials.     

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.     

Different bronchodilator combinations have similar effects on health status in COPD

BACKGROUND: The main treatment in COPD consists of bronchodilator agents. As the severity of disease increases, combined bronchodilators are preferred in place of single agents. Since there is a weak correlation between well being and spirometric parameters, additional life quality questionnaires are used. OBJECTIVES: The main aim of this study was to investigate whether different bronchodilator combinations have similar effects on quality of life measures in COPD. METHODS: Sixty male patients with COPD were randomized into three groups. After a two-week run-in period, life quality scores were determined using the Turkish version of St George's Respiratory Questionnaire (SGRQ). Group 1 was given ipratropium + theophylline (IP + THEO); Group 2 formoterol + theophylline (FOR + THEO) and Group 3 ipratropium + formoterol (IP + FOR). After a 12-week treatment period, symptom, activity and impact scores were again determined. RESULTS: When compared with baseline, all component scores and total scores improved significantly (Delta total score: 16, 15 and 17 units in Groups I, II, and III, respectively), but there was no significant change between groups (p > 0.05). CONCLUSIONS: According to these results, combined bronchodilator treatments have a significant effect on life quality in COPD, but the effects were observed to be similar between the three different combinations tested.     

Long-Acting Inhaled Beta Agonists

The development of long-acting inhaled beta agonists has resulted in a new class of asthma medication combining the unparalleled efficacy of beta₂-selective inhaled agents with the long duration of action previously achieved only by systemic bronchodilators. The two agents in this class are salmeterol (Serevent) and formoterol. Salmeterol was introduced in the United States in April 1994 after several years of availability in Europe and has been enthusiastically embraced by both patients and physicians. Still, as with the shorter-acting beta agonists, concerns persist regarding salmeterol's safety. Formoterol still awaits Food and Drug Administration approval in the United States, but shares many of salmeterol's attributes.