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

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

Onset of action following formoterol Turbuhaler and salbutamol pMDI in reversible chronic airway obstruction

Short-acting beta(2)-agonists are currently recommended for symptom relief in asthma and the treatment of mild, acute exacerbations in COPD. However, formoterol has as fast an onset of action as salbutamol with the additional benefit of longer-lasting bronchodilation (approximately 12 h). Furthermore, systemic side effects observed with formoterol are of a similar duration but less pronounced than with short-acting beta(2)-agonists. In this double-blind, randomized, cross-over study, 20 adult patients with reversible chronic airway obstruction (intrinsic asthma or COPD) inhaled single doses of formoterol 9 microg or salbutamol 100 microg (group A) or formoterol 18 microg or salbutamol 200 microg (group B). FEV(1) was measured prior to and 5, 10, 15, 20, 25 and 30 min following inhalation of study drug. No significant differences in FEV(1) values were observed between group A (P=0.704) or group B (P=0.270) at baseline, or at 5 (Group A: P=0.340; Group B: P=0.559) and 15 min (Group A: P=0.526; Group B: P=0.818) post dose. No adverse events were reported during the study. Formoterol Turbuhaler has as rapid an onset of action as salbutamol pMDI when given at the recommended doses.     

Acute protection against exercise-induced bronchoconstriction by formoterol, salmeterol and terbutaline.

The onset of bronchoprotection as obtained by various beta2-agonists has not been examined in a comparitive study. In this study, the onset of bronchodilation and protection against exercise-induced bronchoconstriction in asthmatics after inhalation of the long-acting beta2-agonists formoterol and salmeterol and the short-acting beta2-agonist terbutaline were measured. Twenty-five subjects with asthma and a history of exercise-induced bronchoconstriction (mean baseline forced expiratory volume in one second (FEV1): 90% predicted; mean fall in FEV1 after exercise: 31% from baseline) were enrolled in this double-blind, double-dummy, placebo-controlled, randomized, four-period crossover study. Exercise challenges were performed on 12 days at either 5, 30, or 60 min after inhalation of a single dose of formoterol (12 microg Turbuhaler), salmeterol (50 microg Diskus), terbutaline (500 microg Turbuhaler) or placebo. Exercise-induced bronchoconstriction (maximum fall in FEV1 or area under the curve) did not differ significantly between terbutaline, formorerol and salmeterol either 5, 30, or 60 min after inhalation of the study medication. In contrast, the onset of bronchodilation was slower after salmeterol compared to terbutaline and formoterol (p<0.05, each), which both showed a similar time course. At all time points between 5 and 60 min, formoterol provided significantly greater bronchodilation than salmeterol (p<0.05). These data indicate that equipotent doses of the bronchodilators salmeterol, formoterol and terbutaline were similarly effective with respect to their short-term protective potency against exercise-induced bronchoconstriction, despite the fact that the time course of bronchodilation was significantly different between the three beta2-agonists.     

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

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

Oxis (formoterol given by Turbuhaler) showed as rapid an onset of action as salbutamol given by a pMDI

Thirty-six adult patients (16 women) with mild to moderate asthma with a mean baseline forced expiratory volume in 1 sec (FEV1) of 73.8% (46-106%) of predicted normal value and mean reversibility of 24.2% (14.6-47.1%) were included in this double-blind, double-dummy, randomized, placebo-controlled and cross-over study. The patients inhaled single doses 4.5 or 9 microg of formoterol (Oxis) via Turbuhaler salbutamol (Ventolin) 100 or 200 microg from a pressurized metered dose inhaler (pMDI) or placebo at five randomized visits. Efficacy was measured by FEV1 pre-dose and then 1, 3, 5, 7, 10, 15, 20, 25 and 30 min after inhalation of the study drug. The primary variable of efficacy was the FEV1-value 3 min after dose intake. No statistically significant differences were found between active treatments. All active treatments gave a higher bronchodilating effect at 3 min than placebo: 10.0, 11.4% for salbutamol 100 and 200 microg and 11.7, 11.8% for formoterol 4.5 and 9 microg (P<0.001 in all cases). There was a correlation between the measured response at 3 min and the subjective experience of the patients. The relative difference vs. placebo remained throughout the study period for all active treatments except for low dose salbutamol. All treatments were well tolerated. In conclusion, formoterol Turbuhaler has as rapid an onset of action as salbutamol pMDI when given at recommended doses.     

Relative therapeutic index between inhaled formoterol and salbutamol in asthma patients

A double-blind, randomized crossover study in 28 asthmatic patients assessed the relative therapeutic index for inhaled formoterol and salbutamol. Pre-drug administration FEV1 (mean 2.08 l) was 49-93% of predicted and reversibility 16-82% after inhalation of salbutamol. Patients inhaled single doses of formoterol (Oxis) (4.5,18 and 54 microg, delivered doses) via Turbuhaler, salbutamol (Ventolin) (200 and 1800 microg) via pressurized metered dose inhaler (pMDI) and placebo at intervals of 48 h or more. Individual maximum FEV1 and minimum S-K+ were calculated. Relative local (maximum FEV1) and systemic (minimum S-K+) dose potencies, and their ratio, the relative therapeutic index, were estimated using a non-linear mixed effect model. The drug effects were well tolerated and dose dependent. A log-linear approximation was used to describe the bronchodilatory effect, whereas a sigmoid approximation was more apt to describe the decrease in serum potassium concentration. A bivariate dose-response model based on these principles was fitted simultaneously to all data. The mean relative therapeutic index between formoterol 4.5-54 microg given via Turbuhaler and salbutamol 200-1800 microg given via pMDI was estimated to be 2.5 in favour of formoterol; this trend was not statistically significant.     

Formoterol (OXIS) Turbuhaler as a rescue therapy compared with salbutamol pMDI plus spacer in patients with acute severe asthma

Formoterol has a similar onset of effect to salbutamol but a prolonged duration of action. However, the relative efficacy of the two drugs in acute severe asthma is not known. This double-blind, double-dummy study compared the safety and efficacy of the maximum recommended daily dose of formoterol and a predicted equivalent dose of salbutamol in 88 patients presenting to the emergency department with acute severe asthma. Patients were randomized to formoterol 54 microg via Turbuhaler or salbutamol 2400 microg via pressurized metered dose inhaler (pMDI) plus spacer in three equal doses over 1 h. Following the full dose, mean FEV1 at 75 min increased by 37% for formoterol and 28% for salbutamol (P = 0.18). The maximum increase in FEV1 over 4 h was significantly greater with formoterol compared with salbutamol (51% vs. 36%, respectively P < 0.05) and formoterol was as effective as salbutamol at improving symptoms and wellbeing. Both treatments were well tolerated. Formoterol caused a greater decrease in serum potassium (difference -0.2 mmol/l). In severe acute asthma, bronchodilator therapy with high-dose (54 microg) formoterol Turbuhaler provided equally rapid improvements in lung function of greater magnitude over 4 h than high-dose (2400 microg) salbutamol pMDI plus spacer.     

Formoterol Turbuhaler as reliever medication in patients with acute asthma.

The aim of this study was to compare the efficacy and safety of formoterol versus salbutamol as reliever medication in patients presenting at an emergency dept with acute asthma. A randomised, double-blind, double-dummy, parallel group study was performed in four Australian emergency treatment centres. The study included a total of 78 adult patients (mean baseline forced expiratory volume in one second (FEV1) 1.83 L; 59% predicted) with acute asthma. Based on the expected dose equivalence of formoterol Turbuhaler 4.5 microg (delivered dose) and salbutamol pressurised metered-dose inhaler 200 microg (metered dose), patients received a total of formoterol Turbuhaler 36 microg (delivered) or salbutamol pressurised metered-dose inhaler with spacer 1,600 microg (metered), divided into two equal doses at 0 and 30 min. FEV1, peak expiratory flow and systemic beta2-agonist effects were monitored for 4 h. The primary variable was FEV1% pred at 45 min. At 45 min, mean increases in FEV1 expressed in % pred were 6.6% and 9.3%, respectively, with a small adjusted mean difference in favour of salbutamol (3.0%, 95% confidence interval -2.0-8.0). Transient increases in systemic beta2-agonist effects occurred predominantly with salbutamol, although no significant treatment differences were observed. Eight patients discontinued due to adverse events. In this study of patients presenting at emergency depts with acute asthma, formoterol Turbuhaler 36 microg was well tolerated and, as rescue therapy, had an efficacy that was not different from that of salbutamol pressurised metered-dose inhaler with spacer 1,600 microg in the number of patients studied.     

The pulmonary and extra-pulmonary effects of high-dose formoterol in COPD: a comparison with salbutamol

OBJECTIVES: Formoterol, a beta(2) agonist with a rapid onset of effect and long duration of action, can be used as maintenance and reliever medication for asthma and COPD. We compared the pulmonary and extra-pulmonary effects of cumulative doses of formoterol and salbutamol in patients with COPD to assess efficacy and safety. METHODOLOGY: In a randomized, double-blind, cross-over study, 12 patients with moderate to severe COPD inhaled, via Turbuhaler, 10 doses of formoterol (total metered dose, 120 microg, equivalent to a 90- microg delivered dose), salbutamol (total metered dose 2000 microg) or placebo at 2-min intervals on separate days. The effects on lung function (FEV(1) and PEF), heart rate, blood pressure, oxygen saturation, corrected QT interval (QTc), T-wave height and plasma potassium were assessed before each dose, 15 min after each dose, and at half-hourly intervals for 3 h following the final dose. RESULTS: Inhalation of formoterol or salbutamol resulted in significant improvement in lung function (measured 30 min after the last dose) when compared with placebo. There were no clinically important or statistically significant changes in heart rate, QTc, T-wave height, plasma potassium, oxygen saturation, or systolic and diastolic blood pressures with formoterol or salbutamol. One patient developed ventricular trigeminy after both formoterol and salbutamol. She had had ventricular ectopics on her screening electrocardiogram. CONCLUSION: Formoterol and salbutamol both produced significant improvement in lung function and were similarly well tolerated in high doses, as might be taken by a patient for relief of COPD symptoms.     

Rapid onset of bronchodilation in COPD: a placebo-controlled study comparing formoterol (Foradil Aerolizer) with salbutamol (Ventodisk)

Formoterol fumarate is a beta2-agonist bronchodilator that combines a fast onset of action with a long duration of action. Its fast onset of action is well documented in asthma but has not been directly compared with that of salbutamol in patients with chronic obstructive pulmonary disease (COPD). This randomized, double-blind, placebo-controlled study was conducted to assess the bronchodilatory effects over the first 3 h after inhalation of single doses of formoterol 24 microg delivered via the Aerolizer dry powder inhaler device (double-blind), or salbutamol 400 microg delivered by a Diskhaler dry powder inhaler (single-blind) in patients with COPD. A total of 24 patients with COPD were randomized [mean age 61.6 +/- 7.8 years, mean forced expiratory volume in 1 sec (FEV1) 1.38 +/- 0.32 l and 45.8 +/- 9.6% of predicted]. Inhalation of formoterol or salbutamol resulted in similar increases in FEV from 0 to 3 h post-dose. Both drugs produced similar bronchodilation by 5 min, which became almost maximal by 30 min. The primary efficacy variable, the area under the curve (AUC) of the FEV increase above predose baseline from 0 to 30 min (AUC(0-30 min)), demonstrated significant effects for formoterol (mean 5.89 +/- 4.67 l min(-1)), and salbutamol (mean 6.06 +/- 4.34 l min(-1)), which were not statistically different from each other but statistically significantly higher (P<0.0001) than that observed with placebo (-0.32 +/- 2.59 l min(-1)). In addition, both formoterol and salbutamol produced similar and rapid increases in forced vital capacity (FVC). In summary, this study confirms the rapid onset of action of formoterol and indicates that the onset of action of formoterol and salbutamol are similar in patients with COPD.     

Long duration of airway but not systemic effects of inhaled formoterol in asthmatic patients

RATIONALE: Formoterol is approved as asthma rescue medication in many countries. The exact duration of the airway vs. systemic effects of formoterol compared with another rescue medication, salbutamol, has not been evaluated. OBJECTIVE: To assess the duration of airway bronchodilatory effects vs. systemic effects of inhaled formoterol and salbutamol in asthmatic patients. METHODS: Twenty-six patients with stable and reversible asthma were given single doses of formoterol dry-powder inhaler (OxisTurbuhaler) 2x9 microg (lower dose; LD) and 6x9 microg (higher dose; HD), salbutamol (VentolinDiskhaler) 3x400 microg (LD) and 9x400 microg (HD), and placebo in a randomized, double-blind, crossover trial. Airway and systemic effects were assessed by forced expiratory volume in 1s (FEV1), serum potassium, blood pressure, corrected QT-interval (QTc), and palpitation and tremor scores. Time with clinically relevant bronchodilation (FEV1 increase 12%) without clinically relevant markers of systemic effects (serum potassium suppression 0.2 mmol/L, QTc-prolongation 20 ms, or heart rate increase 8 beats per minute) was evaluated. RESULTS: Bronchodilation was maintained for 24h with both formoterol doses and for 7-11h with salbutamol. Maximum bronchodilation and systemic effects were similar after formoterol and salbutamol, except for statistically significantly larger maximum heart rate and palpitation and tremor scores after salbutamol. Systemic responses were similarly brief for formoterol and salbutamol (7 h). CONCLUSIONS: The airway effects of inhaled formoterol are of long duration, whereas the systemic effects are of a similarly short duration as salbutamol. Thus, the time with clinically relevant bronchodilation without systemic effects is substantially longer after formoterol than after salbutamol.     

Relief of dyspnoea by beta2-agonists after methacholine-induced bronchoconstriction

Virtually all asthma patients use brorichodilators. Formoterol and salbutamol have a rapid onset of bronchodilating effect, whereas salmeterol acts slower. We studied the onset of improvement of dyspnoea sensation after inhalation with these bronchodilators and placebo to reverse a methacholine-induced bronchoconstriction as a model for an acute asthma attack. Seventeen patients with asthma completed this randomised, double-blind, crossover, double-dummy study. On 4 test days, forced expiratory volume in 1 s (FEV1) and Borg score were recorded and patients were challenged with methacholine until FEV1 fell with > or = 30% of baseline value. Thereafter, formoterol 12 microg via Turbuhaler, salbutamol 50 microg via Turbuhaler, salmeterol 50 microg via Diskhaler, or placebo was inhaled. FEV1 and Borg scores were assessed during the following 60 min. The first sensed improvement of Borg score was significantly (P<0.05) faster achieved with formoterol (geometric mean (Gmean) (range) 1.5 (1-40) min) and salbutamol 1.8 (1-10) min than with salmeterol 4.5 (1-30) min and placebo 3.4 (1-40) min. The Borg score returned significantly faster to the baseline value with formoterol, salbutamol, and salmeterol (Gmean time 13.8 (1-75), 13.4 (1-60), and 18.0 (1-75) min, respectively) than with placebo (33.6 (1-75 min). Formoterol and salbutamol act significantly faster than salmeterol in relieving dyspnoea induced by methacholine-induced bronchoconstriction, in patients with asthma.     

Protection against cold air and exercise-induced bronchoconstriction while on regular treatment with Oxis.

This study aimed to compare the duration of protection against exercise-induced bronchoconstriction (EIB) after inhalation of formoterol (Oxis) Turbuhaler with that of terbutaline Turbuhaler and placebo Turbuhaler in asthmatic patients treated regularly with formoterol Turbuhaler 9 microg b.i.d. and inhaled steroids. The study. performed at three centres (G?teborg and Lund, Sweden, and Trondheim, Norway), consisted of an open-label part with formoterol Turbuhaler 9 microg b.i.d. and a randomized, double-blind, cross-over part with a single dose (on top of the regular treatment) of either formoterol Turbuhaler 9 microg, terbutaline Turbuhaler 0.5 mg or placebo Turbuhaler. The patients attended the clinic six times: twice for screening visits, three times for randomized treatment and once for a follow-up visit. Patients received regular b.i.d. treatment with formoterol 9 microg for a mean period of 16 days. Formoterol gave a post-exercise fall of 12, 10, 15 and 17% in forced expiratory volume in 1 sec (FEV1) 15 min, 4, 8 and 12 h after inhalation. The differences compared with placebo (falls of 26, 22, 23 and 22%) and terbutaline (falls of 17, 18, 22 and 22%) were all statistically significant (P<0.05 for all comparisons). Patients on regular treatment with formoterol Turbuhaler 9 microg b.i.d. have a significant protection against EIB up to 12 h after inhalation of formoterol 9 microg. The protection was also significantly better than that of terbutaline Turbuhaler 0.5 mg.     

Single-dose comparison of formoterol (Oxis) Turbuhaler 6 microg and formoterol Aerolizer 12 microg in moderate to severe asthma: a randomised,crossover study

Formoterol inhaled via Turbuhaler (Oxis) or Aerolizer (Foradil) produces fast and long-lasting bronchodilation in asthmatic patients. While formoterol Turbuhaler provides sustained efficacy for > or =12h at a metered dose of 6 microg (delivered dose 4.5 microg), the recommended metered dose for formoterol Aerolizer is 12 microg (delivered dose unknown). This difference may be attributable to improved lung deposition with the Turbuhaler. This open, randomised, crossover study compared the effects of a single metered dose of formoterol Turbuhaler 6 microg and formoterol Aerolizer 12 microg in 16 patients with stable moderate-to-severe asthma. Pulmonary function, assessed by measuring specific airway conductance (sGaw), was determined at intervals of < or =8h post-inhalation of each drug on separate study days. Both inhalers increased sGaw at all time points. There were no significant differences between the two formulations in onset of activity, maximum effect, duration of effect or area under the response curve. Furthermore, both treatments were well tolerated with no differences in adverse events, blood pressure or heart rate; thus the formoterol Turbuhaler may, therefore, have an improved therapeutic index. This pilot study indicates that the same clinical effect can be achieved with half the metered dose (6 microg) of formoterol Turbuhaler compared with formoterol Aerolizer (12 microg).     

A single high dose of formoterol is as effective as the same dose administered in a cumulative manner in patients with acute exacerbation of COPD

Several clinical trials have shown that the inhaled beta2-agonists with long-acting properties, formoterol and salmeterol, may be effective in acute exacerbations of chronic obstructive pulmonary disease (COPD). However, there is a great deal of controversy regarding the timing and optimal dose of inhaled beta2-agonists in this pathologic condition. In this double-blind, randomised, crossover study, we have compared the bronchodilating effect and the safety of inhaled formoterol administered via Turbuhaler using either a cumulative dose regimen or the equivalent single dose in 16 patients with acute exacerbations of COPD. On the two consecutive days, the patients received, in a randomised order, each of the following active dose regimens: (A): 9 + 9 + 18 microg of formoterol via Turbuhaler (36 microg cumulative delivered dose) or (B): 36 + 0 + 0 microg of formoterol via Turbuhaler. The three doses on each treatment day were administered at 30-mm intervals, with measurements being made 5 and 30 min after each dose. Contemporaneously, we also measured oxygen saturation by pulse oximetry (SpO2) and pulse rate. Both the high dose and the cumulative one induced a significant bronchodilation expressed as change in FEV1. The difference between the two regimens was significant (P=0.0332) only 60 min after the first inhalation. The trend of FVC and IC was similar to that of FEV1. All treatment regimens were well tolerated and no adverse events were reported. Neither the administration ofthe high dose nor that of the cumulative one modified heart rate in a significant manner. Also they did not influence SpO2. This study indicates that a single high dose offormoterol is as effective as the same dose administered in a cumulative manner in patients with acute exacerbation of COPD.     

Onset and duration of action of formoterol and tiotropium in patients with moderate to severe COPD

BACKGROUND: Chronic obstructive pulmonary disease (COPD) management guidelines recommend regular treatment with one or more long-acting bronchodilators for patients with moderate to severe COPD. OBJECTIVE: To compare the onset and duration of action of formoterol and tiotropium in patients with COPD. METHODS: This randomized, multicentre, open-label crossover study in 38 patients with COPD (mean age 64 years; mean FEV(1) 55% predicted) assessed the effect of 7 days of treatment with formoterol (12 microg b.i.d. via Foradil Aerolizer) vs. tiotropium (18 microg o.d. via Spiriva HandiHaler) on lung function measured over a period of 12 h after the first dose on day 1 and the last dose on day 8. RESULTS: The primary efficacy variable, FEV(1)-AUC during the first 2 h post-dose (FEV(1)-AUC(10-120 min)), was significantly higher for formoterol compared with tiotropium, with between-treatment differences of 124 ml (p = 0.016) after the first dose and 80 ml (p = 0.036) after 7 days' treatment in favour of formoterol. FEV(1) measured 12 h after inhalation did not differ statistically significantly between treatments. Adverse events occurred in 2 (5%) patients after treatment with formoterol and in 5 (12%) patients after treatment with tiotropium. CONCLUSION: This study demonstrates faster onset of action and greater bronchodilation of formoterol vs. tiotropium for bronchodilation within the first 2 h of inhalation (FEV(1)-AUC(10-120 min)) and comparable bronchodilation 12 h post-inhalation in patients with moderate to severe COPD.     

Formoterol and salmeterol in partially reversible chronic obstructive pulmonary disease: A crossover, placebo-controlled comparison of onset and duration of action.

BACKGROUND: In contrast to the well-known activity profile in asthma, the precise efficacy and optimum dose schedules of long-acting beta(2)-agonists in chronic obstructive pulmonary disease (COPD) are not clear. OBJECTIVE: In this study, we aimed to compare the onset and the duration of action of a single inhalation of formoterol and salmeterol in COPD patients having partially reversible airway obstruction. METHODS: In a double-blind, randomized, crossover and placebo-controlled study design, the respiratory functions of 22 patients (mean age 57.3+/-5.4 years) having mild to severe COPD (5 mild, 8 moderate and 9 severe) and partially reversible airway obstruction [mean baseline reversibility of forced expiratory volume in 1 s (FEV(1)) 19.3+/-3.1%] were evaluated after inhalation of 12 microg formoterol and 50 microg salmeterol. RESULTS: Regarding the onset of bronchodilator action, the mean absolute increase of 0.20 liters in FEV(1) 10 min after inhalation of formoterol was significantly higher than baseline and that of placebo (0.04 liters), whereas that of salmeterol (0.11 liters) did not reach statistical significance. At 20 min, both formoterol (0.25 liters) and salmeterol (0.20 liters) produced a significant increase in FEV(1) compared with baseline and with that of placebo (0.04 liters). The peak bronchodilator effects occurring at 60 and 120 min following formoterol (0.39 liters) and salmeterol (0.40 liters) inhalation, respectively, were significantly higher than the corresponding levels of placebo (0.02 and -0.12 liters, respectively). Concerning the duration of action, the 12-hour values of both formoterol (0.25 liters) and salmeterol (0.22 liters) were significantly higher than that of placebo (-0.12 liters). The area under the curve values of FEV(1) of formoterol (3.5+/-1.3 l.h) and salmeterol (3.2+/-1.2 l x h) averaged over 12 h were comparable and higher than placebo values (1.2+/-0.5 l x h). After formoterol inhalation 2 patients experienced tremor and 1 had palpitation; 1 tremor and 1 headache attack were noted after salmeterol. For the pharmacologically predictable side effects, there was no difference between the drugs. CONCLUSIONS: In conclusion, this study revealed that a single dose of 12 microg formoterol and 50 microg salmeterol provided comparable bronchodilation within 12 h and had tolerable side effects in patients with mild to severe COPD having partially reversible airway obstruction.     

Effect of formoterol/budesonide combination on arterial blood gases in patients with acute exacerbation of COPD

BACKGROUND: Patients with severe chronic airway obstruction might suffer dangerous hypoxemia after administration of a beta-agonist despite bronchodilation. METHODS: We first compared the acute effects on gas exchange of two doses of formoterol Turbuhaler (9 and 18 microg) in 10 patients with acute exacerbation of COPD. Afterwards, we compared the acute effects of formoterol Turbuhaler 9 microug with those of formoterol/budesonide combination in a single inhaler (Turbuhaler) 9/320 microg in 10 other patients with acute exacerbation of COPD. Finally, we compared the changes in PaO(2) induced by formoterol Turbuhaler 9 microg or formoterol/budesonide combination in a single inhaler (Turbuhaler) 9/320 microg with those in FEV(1) in 10 other patients with acute exacerbation of COPD. Each agent was given on separate days, and the patients' arterial blood gases were measured at baseline and at intervals of 120 min. RESULTS: Small but statistically significant declines in PaO(2) were found after administration of both formoterol 9 and 18 microg. In the second group of patients, formoterol 9 microg alone again induced a significant decrease in PaO(2). However, the simultaneous administration of budesonide 320 microg significantly reduced the acute effect of formoterol on PaO(2). In a third group of 10 patients we confirmed a small but significant decrease in PaO(2) after formoterol alone and the reduction of this effect when budesonide was administered simultaneously. Moreover, we also documented that addition of budesonide amplified the fast onset of action of formoterol. CONCLUSIONS: These results suggest that when treating patients suffering from acute exacerbation of COPD with formoterol, it is prudent to check their arterial blood gases. In any case, combined administration of formoterol and budesonide reduces the potential for acute effects of formoterol on blood-gas tensions.     

Formoterol via Turbuhaler gave better protection than terbutaline against repeated exercise challenge for up to 12 hours in children and adolescents

We aimed to compare the protective effect of single doses of 4.5 and 9 microg of formoterol fumarate (F), 0.5 mg terbutaline sulphate (T) and placebo (P), all via Turbuhaler, against exercise-induced bronchoconstriction (EIB) in children. Twenty-seven asthmatic children, showing a fall of > or =20% in FEV1 after a standardized exercise challenge test (ECT) combined with cold air (-10 degrees C) inhalation, were randomized in this cross-over, double-blind study. They had a mean age of 12.6 years (range 8-17 years), mean baseline FEV1 90% (73.9-105.6%) of predicted normal value. Seventeen children used inhaled glucocorticosteroids (120-750 microg day(-1)). ECTs were performed 15 min and 4, 8, and 12 h after drug administration. F significantly reduced the fall in FEV1 after ECT to 5.4% (15 min), 5.2% (4 h), 8.2% (8 h) and 9.3% (12 h) after 4.5 microg, and 2.5%, 3.0%, 5.0% and 5.4% after 9 microg, compared with a fall of 18.4%, 15.7%, 15.6% and 16.5% in FEV1 after P. The fall after T was 3.3%, 11.6%, 14.4% and 19.1% after 15 min, 4, 8 and 12 h respectively. The difference between F and T was statistically significant from 4 h and onward (P-value for all comparisons < 0.05). Children using a single dose of either formoterol Turbuhaler 4.5 or 9 microg had significantly better bronchoprotection against repeated exercise challenge up to 12 h compared with placebo and from 4 h onward compared with terbutaline Turbuhaler 0.5 mg.     

Onset of action of formoterol/budesonide in single inhaler vs. formoterol in patients with COPD

Formoterol is a beta(2)-agonist bronchodilator that combines a fast onset of action with a long duration of broncholytic effect. An increasing documentation is showing that the combination of a long acting beta(2)-adrenoceptor agonist bronchodilator and an inhaled corticosteroid targets the airways obstruction in patients with COPD. In this study, we have explored whether the acute addition of an inhaled corticosteroid influences the fast bronchodilator response to formoterol. A total of 20 patients with stable COPD were randomized. Single doses of formoterol/budesonide 2 x (4.5/160)microg or formoterol 2 x 4.5 microg were given via Turbuhaler. Serial measurements of FEV(1) were performed over 60 min. Formoterol/budesonide elicited a significantly larger mean FEV(1)-AUC(0-15 min) than formoterol alone. Also the change in FEV(1) 15 min after inhalation of formoterol/budesonide combination (0.197 l; 95% CI: to 0.142-0.252) was greater than that induced by formoterol alone (0.147 l; 95% CI: to 0.092-0.201). The mean increases in FEV(1) were always higher after budesonide/formoterol than formoterol alone, although both treatments induced a significant improvement over baseline at each explored time point. Even the FEV(1)-AUC(0-60 min) after formoterol/budesonide was significantly larger than that after formoterol. Both treatments induced a significant reduction in VAS score but did not modify heart rate in a statistically significant manner. This study indicates that the addition of budesonide influences the fast onset of action of formoterol, but does not induce systemic effects, in patients with stable COPD.