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.

     

Efficacy of salmeterol xinafoate in the treatment of COPD

STUDY OBJECTIVES: To examine and compare the efficacy and safety of salmeterol xinafoate, a long-acting inhaled beta2-adrenergic agonist, with inhaled ipratropium bromide and inhaled placebo in patients with COPD. DESIGN: A stratified, randomized, double-blind, double-dummy, placebo-controlled, parallel group clinical trial. SETTING: Multiple sites at clinics and university medical centers throughout the United States. PATIENTS: Four hundred eleven symptomatic patients with COPD with FEV1 < or = 65% predicted and no clinically significant concurrent disease. Interventions: Comparison of inhaled salmeterol (42 microg twice daily), inhaled ipratropium bromide (36 microg four times a day), and inhaled placebo (2 puffs four times a day) over 12 weeks. RESULTS: Salmeterol xinafoate was significantly (p < 0.0001) better than placebo and ipratropium in improving lung function at the recommended doses over the 12-week trial. Both salmeterol and ipratropium reduced dyspnea related to activities of daily living compared with placebo; this improvement was associated with reduced use of supplemental albuterol. Analyses of time to first COPD exacerbation revealed salmeterol to be superior to placebo and ipratropium (p < 0.05). Adverse effects were similar among the three treatments. CONCLUSIONS: These collective data support the use of salmeterol as first-line bronchodilator therapy for the long-term treatment of airflow obstruction in patients with COPD.     

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.     

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.     

Use of a long-acting inhaled beta2-adrenergic agonist, salmeterol xinafoate, in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a condition in which continuous bronchodilation may have clinical advantages. This study evaluated salmeterol, a beta-agonist bronchodilator with a duration of action substantially longer than that of short-acting beta-agonists, compared with ipratropium, an anticholinergic bronchodilator, and placebo in patients with COPD. Four hundred and five patients with COPD received either salmeterol 42 microg twice daily, ipratropium bromide 36 microg four times daily, or placebo for 12 wk in this randomized, double-blind, parallel-group study. Patients were stratified on the basis of bronchodilator response to albuterol (> 12% and > 200-ml improvement) and were randomized within each stratum. Bronchodilator response was measured over 12 h four times during the treatment period. Salmeterol provided similar maximal bronchodilatation to ipratropium but had a longer duration of action and a more constant bronchodilatory effect with no evidence of bronchodilator tolerance. Both active treatments were well tolerated. Salmeterol was an effective bronchodilator with a consistent effect over this 12-wk study in patients with COPD, including those "unresponsive" to albuterol. The long duration of action of salmeterol offers the advantage of twice daily dosing compared with the required four times a day dosing with ipratropium.     

A comparison between inhaled salmeterol and theophylline in the short-term treatment of stable chronic obstructive pulmonary disease

BACKGROUND: International guidelines indicate that the long-acting bronchodilators play a key role in the treatment of patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to assess the short term efficacy and safety of 50 and 100 microg bid inhaled salmeterol, compared with placebo and orally dose titrated slow-release theophylline in patients with stable COPD. METHODS: Thirteen patients (67+/-7 years, three females) with moderate-to-severe COPD (FEV1<70% predicted and >30% predicted) and with poor reversibility (post-bronchodilator FEV1<12% and <200 ml from pre-bronchodilator values) completed this single centre randomised, double-blind, double-dummy, four-phase cross-over clinical trial. Patients were randomised to treatment after a 2-week oral corticosteroid trial and a theophylline titration phase. Each treatment lasted 2 week with a 2-week washout period. Values at the end of treatments were compared. RESULTS: Inhaled salmeterol at both tested doses was better than placebo in improving lung function (FEV1, FVC, and morning PEF) of stable patients with moderate COPD over a period of 2 weeks. Although slight (about 170 ml, 150 ml, and 120 ml/min on average, for FEV1, FVC, and PEF, respectively) the improvement was significant. The effects seem to improve only slightly with the higher dose. Salmeterol appeared to be more effective than theophylline treatment when compared to placebo, as theophylline improved significantly, but less, the FEV1 (about 80 ml, on average) without affecting any of the other lung function variables. Salmeterol 100 microg was significantly better than theophylline in improving morning PEF. Four patients reported five adverse events while receiving placebo and 2 and 3 patients reported 2 and 3 adverse events, respectively, during salmeterol 50 microg and salmeterol 100 microg phases. None was considered drug related. Five patients experienced 13 adverse events with theophylline treatment, four of which were considered drug related. CONCLUSION: Inhaled salmeterol improves lung function in stable patients with moderate-to-severe and poorly reversible COPD. The magnitude of improvement in FEV1 observed in this study is similar to that found in longer and larger studies on similar populations of patients. In those studies, that improvement was associated with a better quality of life and less symptoms. Theophylline determined a smaller improvement in FEV1 with more unpleasant side effects that both doses of inhaled salmeterol, though there was no significant difference. It is concluded that salmeterol is an effective and well tolerated therapy, potentially preferable to theophylline, at least in the short-term management of stable COPD.     

In patients with COPD, treatment with a combination of formoterol and ipratropium is more effective than a combination of salbutamol and ipratropium : a 3-week, randomized, double-blind, within-patient, multicenter study

STUDY OBJECTIVES: To compare the efficacy of adding formoterol or salbutamol to regular ipratropium bromide treatment in COPD patients whose conditions were suboptimally controlled with ipratropium bromide alone. DESIGN: A randomized, double-blind, double-dummy, two-period, crossover clinical trial. SETTING: Twenty-four clinics and university medical centers in nine countries. PATIENTS: One hundred seventy-two patients with baseline FEV(1) < or = 65% predicted, with FEV(1) reversibility to salbutamol not exceeding the normal variability of the measurement, and symptomatic despite regular treatment with ipratropium bromide. INTERVENTIONS: Each patient received two treatments in random order: either inhaled formoterol dry powder, 12 microg bid, in addition to ipratropium bromide, 40 microg qid for 3 weeks, followed by salbutamol, 200 microg qid, in addition to ipratropium, 40 microg qid for 3 weeks, or vice versa. MEASUREMENTS AND RESULTS: Efficacy end points included morning premedication peak expiratory flow (PEF) during the last week of treatment (primary end point), the area under the curve (AUC) for FEV(1) measured for 6 h after morning dose on the last day of treatment, and symptom scores (from daily diary recordings). Morning PEF and the AUC for FEV(1) were significantly better for formoterol/ipratropium than for salbutamol/ipratropium (p = 0.0003 and p < 0.0001, respectively). The formoterol/ipratropium combination also induced a greater improvement in mean total symptom scores (p = 0.0042). The safety profile of the two treatments was comparable. CONCLUSIONS: In COPD patients requiring combination bronchodilator treatment, the addition of formoterol to regular ipratropium treatment is more effective than the addition of salbutamol.     

Tiotropium Bromide

Tiotropium bromide (Spiriva) is a long-acting anticholinergic bronchodilator that maintains bronchodilation for at least 24 hours, allowing once-daily administration. The active moiety is the tiotropium cation (tiotropium); tiotropium bromide 22.5 micrograms is equivalent to 18 micrograms of tiotropium cation. Greater improvements in lung function from baseline (primary endpoint mean trough FEV(1)) were observed with inhaled tiotropium 18 micrograms once daily than with placebo in 6-month and 1-year randomized, double-blind trials in patients with COPD. Tiotropium improved lung function (trough FEV(1) response) more effectively than ipratropium bromide (ipratropium) 40 micrograms four times daily in 1-year clinical trials, and was at least as effective as salmeterol 50 micrograms 12-hourly in 6-month trials. Preliminary data suggest that tiotropium alone or in combination with once-daily formoterol has a greater bronchodilator effect than twice-daily formoterol in patients with COPD. Improvements in patients' perception of health-related quality of life (HR-QOL) or dyspnea were greater with tiotropium than with placebo or ipratropium, and were similar to those with salmeterol. Reductions in the frequency and severity of acute exacerbations and in the use of rescue medication were also greater with tiotropium than with ipratropium or placebo. There was no evidence of tachyphylaxis with tiotropium during 1-year clinical trials. Inhaled tiotropium was generally well tolerated in clinical trials. Apart from dry mouth, the type and incidence of adverse events with tiotropium were similar to those with ipratropium, salmeterol or placebo in patients with COPD. In conclusion, inhaled tiotropium 18 micrograms once daily improved lung function, dyspnea, and HR-QOL, and decreased the incidence of acute COPD exacerbations and the use of rescue medication relative to placebo or ipratropium in clinical trials in patients with COPD. Tiotropium was at least as effective as salmeterol in terms of bronchodilator efficacy and improvements in dyspnea or HR-QOL. With the exception of dry mouth, the tolerability profile of tiotropium was similar to that with placebo, ipratropium, or salmeterol. Consequently, inhaled tiotropium is likely to be a valuable option for first-line, long-term maintenance therapy in the management of bronchoconstriction in patients with symptomatic COPD. Tiotropium bromide has a quaternary ammonium structure and acts as an anticholinergic bronchodilator; the active moiety is the tiotropium cation (tiotropium). A 22.5 micrograms dose of tiotropium bromide provides 18 micrograms of tiotropium. Orally inhaled tiotropium bromide antagonizes the muscarinic M(1), M(2), and M(3) receptors located in airway smooth muscle, reversing vagally mediated bronchoconstriction. Receptor binding assays and in vitro tests indicate that tiotropium bromide is kinetically selective for M(1) and M(3) receptors over the M(2) receptor, unlike ipratropium bromide, which is nonselective. Animal and in vitro studies showed that tiotropium bromide was more potent ( approximate, equals 20-fold) than ipratropium bromide in displacing [(3)H]N-methylscopolamine (NMS) from muscarinic receptors, and had a more sustained protective effect (>70% inhibition) against NMS binding. Tiotropium bromide was a more potent inhibitor of bronchial contraction than atropine ( approximate, equals 23-fold), and had a slower onset and markedly longer duration of action than atropine or an equipotent dose of ipratropium bromide. Aerosol particle penetration is improved with tiotropium, without delaying mucus clearance from the lungs. Tiotropium 4.5-36 micrograms once daily for 4 weeks increased mean trough and average FEV(1) and FVC and mean PEFR values from baseline compared with placebo, with no evidence of tachyphylaxis. Improvements in trough FEV(1) from baseline with tiotropium 4.5-36 micrograms were not dose dependent. Based on a lack of dose response, the optimal once-daily tiotropium dosage is 18 micrograms. Steady-state trough FEV(1) values are achieved within 48 hours of commencing tiotrochodilation (for >/=24 hours) and an attenuation of the nocturnal decline in FEV(1) that were unaffected by timing of the daily tiotropium dose were seen in randomized, double-blind, placebo-controlled studies in patients with stable COPD. The drug improved static and dynamic lung hyperinflation (evidenced by reduced trapped air volume and increased tidal volume and end-of-exercise inspiratory capacity), and improved exertional dyspnea (during activities of daily living and exertion) and exercise tolerance compared with placebo in randomized, double-blind studies. In patients with stable COPD, improved sleep-related oxygen desaturation that was unaffected by the timing of the daily dose was seen with tiotropium but not with placebo. Clinically significant treatment-related disorders of conduction or rhythm, or changes in heart rate were not observed with tiotropium in this patient group. Mean maximal plasma concentrations (C(max)) were observed within 5 minutes of inhalation of a single dose of tiotropium 18 micrograms in patients with COPD. Plasma drug levels declined to minimum concentrations (C(min)) within 1 hour of treatment in healthy volunteers. Mean steady-state C(max) concentrations (16 ng/L) were achieved after 2-3 weeks of once-daily inhaled tiotropium 18 micrograms in elderly patients with COPD; tiotropium does not appear to accumulate once steady-state has been achieved.The estimated absolute bioavailability of tiotropium at steady state in healthy volunteers was approximately 20-25%, and approximately 72% of the drug is bound to plasma proteins. Excretion of tiotropium is predominantly renal (through active secretion by the kidneys), although in vitro studies suggest that cytochrome P450 (CYP) oxidation (possibly involving CYP2D6 and CYP3A4 enzymes) may have a minor role. In patients with COPD, renal excretion of the unchanged drug at 24 hours (Ae(24)) was approximately 7%. The mean plasma elimination half-life after single or multiple doses in healthy volunteers and elderly patients with COPD was approximately 5-6 days. The renal clearance and urinary excretion of tiotropium decrease with increasing age; however, these changes are not considered to be clinically significant. Because of altered steady-state C(max), C(min), area under the concentration-time curve, and Ae(24) values, caution is required with tiotropium administration in patients with moderate-to-severe renal impairment. The pharmacokinetics of tiotropium in patients with severe renal or hepatic impairment have not been studied. Tiotropium does not interact with drugs such as cimetidine or ranitidine, which are also eliminated by active renal secretion. Orally inhaled tiotropium bromide has been evaluated as a bronchodilator for the management of patients with COPD in randomized, double-blind 6-month and 1-year trials, and in several shorter studies. In clinical trials, COPD was diagnosed according to the American Thoracic Society guidelines. The bronchodilator effect was expressed as the trough FEV(1) response (the mean change in FEV(1) from baseline measured 1 hour prior to and immediately before a scheduled dose), and was the primary endpoint in all but two clinical trials. The bronchodilator effect with tiotropium 18 micrograms once daily was superior to that with placebo in several well designed trials in patients with COPD. Moreover, greater improvements in mean peak and average FEV(1) responses occurred with tiotropium but not with placebo. Mean trough, peak, and average FVC responses, and weekly mean morning and evening PEFR values were also improved to a greater extent with tiotropium than with placebo. Tiotropium demonstrated a greater bronchodilator effect than ipratropium bromide (hereafter referred to as ipratropium when used at approved dosages) 40 micrograms four times daily in two 1-year trials in patients with COPD. Mean peak and average FEV(1), mean trough FVC responses, and weekly mean morning and evening PEFR values were also increased to a greater extent with tiotropium than with ipratropium. In one of the two 6-month trials that compared the efficacy of tiotropium with that of inhaled salmeterol 50 micrograms twice daily, greater improvements from baseline in mean trough, peak, and average FEV(1) and FVC responses were seen with tiotropium than with salmeterol. Increases in weekly mean evening, but not morning, PEFR values were generally greater with tiotropium than salmeterol. In the second trial, improvement in the primary endpoint (mean trough FEV(1) response from baseline) with tiotropium or salmeterol was similar, although peak and average responses were superior with tiotropium. Preliminary results from a 6-week crossover study in patients with COPD suggested that tiotropium alone or in combination with once-daily formoterol improved mean trough and average FEV(1) and trough FVC values from baseline to a greater extent than twice-daily formoterol. More patients achieved a clinically important improvement (increase of >/=1 unit) in the transitional dyspnea index focal score (a measure of dyspnea-related impairment) with tiotropium than with placebo in the 1-year trials. Tiotropium was superior to ipratropium in 1-year trials, and was at least as effective as salmeterol in 6-month trials, in achieving a clinically important improvement in focal scores. Tiotropium recipients experienced fewer COPD exacerbations than placebo or ipratropium recipients and had fewer and shorter COPD-related hospitalizations compared with placebo recipients. Unlike salmeterol, tiotropium lengthened the time to onset of the first exacerbation and decreased the number of exacerbations compared with placebo in two 6-month trials. Similar proportions of tiotropium, salmeterol, and placebo recipients required COPD-related hospitalizations. (ABSTRACT TRUNCATED)     

Ipratropium bromide hydrofluoroalkane inhalation aerosol is safe and effective in patients with COPD

STUDY OBJECTIVE: To compare the efficacy and safety of ipratropium bromide reformulated with the chlorofluorocarbon (CFC)-free propellant hydrofluoroalkane (HFA)-134a (ipratropium bromide HFA) to that of the marketed ipratropium bromide inhalation aerosol (containing CFC) in patients with COPD. DESIGN: This was a randomized, double-blind, parallel-group, placebo-controlled, multicenter trial. The primary efficacy parameter was acute bronchodilator response. The primary end points were peak change in FEV(1) from baseline and area under the response-time curve. SETTING: Thirty-one clinical centers in the United States participated in this project. PATIENTS: A total of 507 patients with moderate-to-severe COPD were randomized, and 444 patients completed the trial. INTERVENTIONS: Twelve weeks of treatment four times daily with one of the following: ipratropium bromide HFA, 42 microg; ipratropium bromide HFA, 84 microg; HFA placebo; ipratropium bromide inhalation aerosol, 42 microg; or CFC placebo. Measurements and results: Patients in all active treatment groups had significant bronchodilator responses as shown by increases in mean FEV(1) from baseline of at least 15%. Bronchodilator response in all active treatment groups was also significantly more than their respective placebo treatments based on FEV(1), area under the time-response curve from 0 to 6 h, and peak response. FVC results were similar to those seen with FEV(1). There were no significant differences in adverse events, laboratory findings, or ECG findings among the treatment groups. CONCLUSIONS: Ipratropium bromide HFA, 42 and mgr;g, provided bronchodilation comparable to the marketed ipratropium bromide CFC, 42 and mgr;g, over 12 weeks of regular use.     

Effects of formoterol on exercise tolerance in severely disabled patients with COPD

OBJECTIVE: We wished to evaluate the effects of inhaled formoterol, a long-acting beta(2)-adrenergic agonist, on exercise tolerance and dynamic hyperinflation (DH) in severely disabled chronic obstructive pulmonary disease (COPD) patients. DESIGN: In a two-period, crossover study, 21 patients with advanced COPD (FEV(1)=38.8+/-11.7% predicted, 16 patients GOLD stages III-IV) were randomly allocated to receive inhaled formoterol fumarate 12 microg twice daily for 14 days followed by placebo for 14 days, or vice versa. Patients performed constant work-rate cardiopulmonary exercise tests to the limit of tolerance (Tlim) on a cycle ergometer: inspiratory capacity (IC) was obtained at rest and each minute during exercise. Baseline and transitional dyspnoea indices (BDI and TDI) were also recorded. RESULTS: Eighteen patients completed both treatment periods. Formoterol treatment was associated with an estimated increase of 130 s in Tlim compared with placebo (P=0.052): this corresponded to a 37.8% improvement over placebo (P=0.012). Enhanced exercise tolerance after bronchodilator was associated with diminished DH marked by higher inspiratory reserve and tidal volumes at isotime and exercise cessation (P<0.05). There was no significant difference between formoterol and placebo on exercise dyspnoea ratings; however, all domains of the TDI improved (P相似文献   

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.     

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.     

Ipratropium Bromide HFA

Ipratropium bromide is a nonselective antagonist of the muscarinic receptors located on airway smooth muscle, and is delivered via a metered-dose inhaler (MDI). Because of the requirement to phase out chlorofluorocarbon (CFC)-propelled MDIs, the ipratropium bromide inhalation aerosol MDI has been redesigned with a hydrofluoroalkane as the propellant (ipratropium bromide HFA). Ipratropium bromide HFA has recently been approved in the US for the maintenance treatment of bronchospasm associated with COPD. Ipratropium bromide HFA 42 microg four times daily (one dose [42 microg] is delivered via two puffs of the inhaler) demonstrated comparable efficacy to that of ipratropium bromide CFC 42 microg four times daily, as measured by spirometric testing, in a large, randomized, double-blind, placebo-controlled, 12-week trial in patients with stable COPD. Similarly, four-times-daily ipratropium bromide HFA 42 microg and ipratropium bromide CFC 42 microg provided a comparable degree of bronchodilation in patients with stable COPD during a 1-year, open-label study primarily designed to assess safety. In both studies, the tolerability profiles of ipratropium bromide HFA and ipratropium bromide CFC were comparable. The most common adverse events were related to respiratory system disorders. During the 1-year study, dry mouth was reported by 1.3% and 0.7% of patients in the ipratropium bromide HFA or ipratropium bromide CFC groups.     

Is there any difference between effects of ipratropium bromide and formoterol on exercise capacity in moderate COPD patients?

The effects of anticholinergic agents or long acting beta(2)-agonists on exercise capacity in chronic obstructive pulmonary disease (COPD) improves various out come measures but there is not enough double-blind study which included comparison of different medications. The aim of this study was to compare the effect of ipratropium bromide and formoterol on exercise capacity and also to determine the relationship between this improvement in functional parameters and exercise capacity for each treatment in patients with COPD. This study was performed as randomized, double blind and two period crossover design. Ten volunteer stable COPD patients were recruited from outpatient COPD clinic. At the initial visit medical data were recorded. One week later baseline measurements; pulmonary function tests and cardiopulmonary exercise testing were performed, afterwards, patients received ipratropium bromide 40 microg four times a day or formoterol 12 microg two times a day for two weeks. After a washout period, medications were crossed for another two weeks. After each of treatment period, all tests were performed. Nine subjects were male and mean age was 51.1 +/- 5.45 years, all of them were heavy smokers, level of COPD was mild to moderate (FEV(1)= 69%, FEV(1)/FVC= 68%). While formoterol significantly improved FEV(1), FEV(1)/FVC %, ipratropium significantly improved FEV(1), FEF(25-75), peak oxygen uptake and minute ventilation. Moreover, both of the medications increased exercise time. There were no differences between effects of ipratropium bromide and formoterol on exercise capacity and functional parameters. We observed that ipratropium bromide and formoterol have similar improvement in exercise capacity in COPD patients. The improvement in exercise capacity also correlated with increase in FEV(1).     

A randomized study of tiotropium Respimat Soft Mist inhaler vs. ipratropium pMDI in COPD

The aim of these studies was to compare the efficacy and the safety of tiotropium, delivered via Respimat Soft Mist Inhaler (SMI), a novel multi-dose, propellant-free inhaler, with ipratropium pressurized metered-dose inhaler (pMDI) in chronic obstructive pulmonary disease (COPD) patients. Two identical, 12-week, multi-national, randomized, double-blind, double-dummy, parallel-group, active- and placebo-controlled studies were performed. COPD patients were randomized to treatment with either inhaled tiotropium (5 or 10 microg) via Respimat SMI administered once daily, ipratropium (36 microg) pMDI QID or placebo. The primary endpoint was the mean trough forced expiratory volume in 1s (FEV(1)) response after 12 weeks of treatment. Secondary endpoints included other spirometry measures and rescue medication use. A total of 719 patients were randomized; the majority were male (69%) with a mean pre-bronchodilator FEV(1) (% predicted) of 40.7%. The mean treatment differences between tiotropium 5 and 10 microg and placebo for the primary endpoint (mean trough FEV(1) response at week 12) were 0.118 and 0.149L, respectively (both P<0.0001). Treatment differences between tiotropium 5 and 10 microg and ipratropium were 0.064L (P=0.006) and 0.095L (P<0.0001). The increases in peak FEV(1), FEV(1) AUC((0-6h)) and FVC for both tiotropium doses were statistically superior to placebo (P<0.01) and higher than ipratropium. All active treatments significantly reduced the rescue medication use compared with placebo, but only tiotropium 10 microg was statistically superior to ipratropium (P=0.04). The incidence of adverse events was comparable across groups. In conclusion, tiotropium 5 and 10 microg daily, delivered via Respimat SMI, significantly improved lung function compared with ipratropium pMDI and placebo.     

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.     

Influence of higher than conventional doses of oxitropium bromide on formoterol-induced bronchodilation in COPD

We examined the influence of higher than conventional doses of oxitropium bromide on formoterol-induced bronchodilation in patients with partially reversible stable COPD. Twenty outpatients inhaled one or two puffs of formoterol (12 microg puff(-1)), or placebo. Two hours after inhalation, a dose-response curve to inhaled oxitropium bromide (100 microg puff(-1)) or placebo was constructed using one puff, one puff, two puffs and two puffs, for a total cumulative dose of 600 microg oxitropium bromide. Doses were given at 20-min intervals and measurements made 15 min after each dose. On six separate days, all patients received one of the following: (1) formoterol 12 microg + oxitropium bromide 600 microg, (2) formoterol 12 microg + placebo, (3) formoterol 24 microg + oxitropium bromide 600 microg, (4) formoterol 24 microg + placebo, (5) placebo + oxitropium bromide 600 microg, or (6) placebo + placebo. Both formoterol 12 microg and 24 microg induced a good bronchodilation (formoterol 12 microg, 0.19-0.20 l; formoterol 24 microg 0.22-0.24 l). The dose-response curve of oxitropium, but not placebo, showed an evident increase in FEV1, with a further significant increase of respectively 0.087 l and 0.082 l after the formoterol 12 microg and formoterol 24 microg pre-treatment. This study shows that improved pulmonary function in patients with stable COPD may be achieved by adding oxitropium 400-600 microg to formoterol. There is not much difference in bronchodilation between combining oxitropium with formoterol 12 microg or 24 microg. In any case, formoterol 24 microg alone seems sufficient to achieve the same bronchodilation induced by oxitropium 600 microg alone in most patients.     

Efficacy and safety of oxitropium bromide,theophylline and their combination in COPD patients: a double-blind,randomized, multicentre study (BREATH Trial)

We compare the efficacy including spirometry, peak expiratory flow (PEFR) and quality of life and safety of an 8-week treatment with inhaled oxitropium, theophylline or their combination in patients with mild-to-severe chronic obstructive pulmonary disease (COPD). We conducted a multicentre, double-blind, double-dummy randomized, parallel-group study at 29 Italian outpatients clinics. A group of 236 patients with mild-to-severe COPD (baseline FEV1 < or = 70% of predicted value) were recruited. Treatments were as follows: Inhaled oxitropium bromide 200 microg (N=75), sustained-release oral theophylline 300 mg (N=81) or their combination (N=80), taken twice daily. Spirometry (FEV1 and FVC) was evaluated every 4 weeks, and morning and evening PEFR (before and 2-4 h after drug intake) was measured daily. Symptoms, cough and dysponea, were recorded daily. Health status was evaluated at baseline and week 8 using the disease specific St George' Respiratory Questionnaire (SGRQ). Any adverse event occurring during the treatment period was recorded on a diary card. FEV1 and FVC improved in all the groups at 4 and 8 weeks, but the difference between treatment groups did not reach statistically significant levels. Differences between groups in pre-dosing morning and evening PEFR were not significant. Post-dosing morning and evening PEFR were increased and the largest increase was seen in patients treated with both drugs. However, differences between groups was significant only for evening values (P=0.008). The proportion of patients who experienced a decrease in symptoms was high in all groups but no differences among groups were observed. SGRQ total scores decreased in all treatment groups after 8 weeks, particularly in the oxitropium and combination groups. Clinically significant change (> or = 4 units) was only observed in patients treated with oxitropium bromide whether with or without theophylline. Adverse events related to treatments were higher in the group treated with theophylline alone (P < 0.02). We conclude that inhaled oxitropium bromide alone was associated with an improvement in FEV1, PEFR and symptoms in patients with COPD that was not statistically different from that of oral theophylline alone or of the combination of both drugs. Oxitropium bromide in combination with theophylline provided a greater improvement in evening post-dosing PEFR. Oxitropium bromide alone or in combination with theophylline improved the quality of life better than theophylline alone.     

Regular versus as-needed short-acting inhaled beta-agonist therapy for chronic obstructive pulmonary disease

Regular short-acting inhaled beta-agonist therapy is of uncertain benefit in patients with chronic obstructive pulmonary disease (COPD). We conducted a randomized, concealed, double-blind, placebo-controlled crossover trial in two periods, each of 3-mo duration, involving 53 patients with a smoking history of > 20 pack-years, an FEV1 of < 70% predicted, and an FEV1/VC ratio of < 0.7 after inhalation of 200 microg albuterol. All patients received regular ipratropium bromide at 20 microg per puff in 2 puffs four times daily, beclomethasone at 250 microg per puff or equivalent corticosteroid in 2 puffs twice daily, and open-label inhaled albuterol as needed. Interventional therapy consisted of regular inhaled albuterol (100 microg per puff, in 2 puffs four times daily) versus placebo. Patients used twice as much active albuterol in the regular use period (mean: 8.07 puffs of coded and 4.68 puffs of open-label medication; total: 12.75 puffs daily) than during the as-needed period (mean: 6.34 puffs of open-label albuterol daily). Despite greater beta-agonist use, patients showed similar results during treatment and control periods for all outcomes. Differences between active and placebo periods were: FEV1: -0.04 L (95% confidence interval [CI]: -0.09 to 0.01 L); slow vital capacity: 0.04 L (95% CI: -0.12 to 0.20 L); 6-min walk test distance: -3.1 m (95% CI: -16.8 to 10.5 m); and Chronic Respiratory Questionnaire scores for dyspnea: 0.02 (95% CI: -0.13 to 0.16); fatigue: -0.02 (95% CI: -0.25 to 0.20); mastery: 0.01 (95% CI: -0.20 to 0.24); and emotional function: 0.02 (95% CI: -0.20 to 0.24). We found that in patients with COPD, use of regular short-acting inhaled beta-agonists resulted in twice as much beta-agonist use without physiologic or clinical benefit as did use on an as-needed basis.     

Formoterol for maintenance and as-needed treatment of chronic obstructive pulmonary disease

Formoterol is a long-acting beta2-agonist with a rapid onset of effect in patients with chronic obstructive pulmonary disease (COPD), making it potentially suitable for both maintenance and as-needed bronchodilator treatment. To evaluate the efficacy and tolerability of maintenance formoterol in patients with COPD and to compare the effects of additional formoterol as needed with terbutaline. In this 6-month, double-blind study, 657 patients with COPD (40 years, forced expiratory volume in 1s [FEV1] 40-70% predicted normal) were randomized to formoterol 9 microg twice daily (bid) plus terbutaline 0.5 mg as needed (FORM bid), formoterol 9 microg bid plus formoterol 4.5 microg as needed (FORM bid+prn), or placebo bid plus terbutaline 0.5 mg as needed (placebo), all administered via Turbuhaler. Primary efficacy variables were FEV1 and the sum of breathlessness and chest tightness scores combined symptom score. Formoterol significantly (P<0.01) increased FEV(1) compared with placebo: FORM bid 6.5% (95% CI: 2.5, 10.7%); FORM bid+prn 11.8% (95% CI: 7.7, 16.2%). Combined symptom score decreased significantly in both formoterol groups compared with placebo: FORM bid -0.27 (95% CI: -0.49, -0.06; P=0.012); FORM bid+prn -0.32 (95% CI: -0.53, -0.11; P=0.0026). Similar significant (P<0.05) improvements were seen in both formoterol groups for morning peak expiratory flow, cough and sleep scores, and reliever use. In this study, formoterol 9 microg bid via Turbuhaler as maintenance therapy, with either formoterol or terbutaline as rescue medication, provided sustained improvements in lung function and COPD symptoms. Both formoterol regimens were well tolerated with no differences in adverse events or electrocardiogram profiles.