Formoterol Turbuhaler 4.5 microg (delivered dose) has a rapid onset and 12-h duration of bronchodilation

Clinical trials show that formoterol (Oxis) Turbuhaler 4.5 microg delivered dose (6 microg metered dose) has a rapid onset of bronchodilation similar to that of salbutamol and a 12-h duration of action. Maximum increase in FEV(1) and duration of bronchodilation are dose-dependent, the 4.5 microg dose being the lowest dose tested giving both effects.Clinical studies investigating onset of bronchodilation show a significant increase in specific airway conductance occurring within 1 min after inhalation of formoterol Turbuhaler 4.5 microg. When measured from 3-20 min after inhalation, formoterol Turbuhaler 4.5 microg showed similar increases in FEV(1) to salbutamol administered via pMDI. No difference in onset of bronchodilation was observed between the formoterol Turbuhaler 4.5 and 9 microg doses.Single-dose studies and studies of 1-12 weeks' duration show that formoterol Turbuhaler 4.5 microg produces a significant and clinically important mean bronchodilating effect for > or =12 h after inhalation. In the cited studies no significant differences in duration of bronchodilation were observed between the formoterol Turbuhaler 4.5 and 9 microg doses.Conclusion: clinical data show that formoterol Turbuhaler 4.5 microg is an effective dose in patients with asthma, with a rapid onset of bronchodilation and a duration of at least 12 h.     

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.     

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.     

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.     

Comparison of the bronchodilating effects of inhaled formoterol,salmeterol and salbutamol in asthmatic patients

Ten subjects with various degrees of asthma severity underwent a three-day trial, with the aim of evaluating the bronchodilating effect of inhaled formoterol (12 micro g), in comparison with salbutamol (200 micro g) and salmeterol (50 micro g). The bronchodilation afforded by formoterol paralleled that of salbutamol in rapidity (mean percentage increases in functional measurements (FEV(1)) vs. baseline recorded 5 min after drug administration: 7.7%, 9.3%, and 0.3% for salbutamol, formoterol and salmeterol, respectively) and that of salmeterol in duration (mean percentage increases in FEV(1) vs. baseline recorded 12h after drug administration: 16.8% and 15.9% for formoterol and salmeterol, respectively). Moreover, the maximal effect of formoterol resulted to be slightly higher in comparison with salbutamol (P<0.001) and salmeterol (P<0.05); in this regard, the mean percentage increases in FEV(1) vs. baseline recorded 2h after salbutamol and formoterol, and 4h after salmeterol were 22.3%, 29.5%, and 24.6%, respectively. Therefore, these results suggest that formoterol can be used, in addition to its utilization as long-acting bronchodilator, also as an effective rescue medication for the immediate relief of asthma symptoms.     

The 24 h duration of bronchodilator action of the budesonide/formoterol combination inhaler

INTRODUCTION: The duration of bronchodilator action of the long-acting beta-agonist formoterol when administered in the evening has not been investigated. In this study we have investigated whether a single evening dose of formoterol, administered from the combination budesonide/formoterol (BUD/F) Turbuhaler significantly attenuates the circadian rhythm in airway tone over 24 h. METHODS: Twenty subjects with mild to moderate asthma (mean FEV1 84% predicted) participated in a double-blind, placebo-controlled, cross-over study. Subjects inhaled, in random order, placebo or BUD/F (2x100/6 microg) administered in the evening (2000 h) on two separate occasions. Lung function measurements including FEV1, specific airways conductance (sGaw) and maximum expiratory flow at 25-75% of vital capacity (MEF(25-75%)) were assessed at baseline, at 1 h and subsequently every 4 h post-dose for 24 h. RESULTS: Compared with placebo, BUD/F significantly improved the three measures of airways function throughout the 24 h period, with a difference in FEV1 at 24 h of 0.20L (0.04-0.35L). BUD/F attenuated the biphasic pattern of the circadian rhythm in airway tone. CONCLUSION: The single evening administration of formoterol from the combination BUD/F inhaler resulted in a duration of bronchodilation of at least 24 h.     

Total reversibility testing as indicator of the clinical efficacy of formoterol in COPD

RATIONALE: The Global Initiative for Chronic Obstructive Lung Disease guidelines recommend bronchodilator reversibility testing to guide treatment decisions. This study evaluated the relationship between the change in forced expiratory volume in 1 s (FEV1) with salbutamol or formoterol and the clinical effects of a 4-week formoterol (Foradil) treatment. METHODS: At Visit 1, patients (n = 448) with stable chronic obstructive pulmonary disease took an FEV1 reversibility test using 200 microg salbutamol via a metered dose inhaler. At Visit 2 (Day 0), an FEV1 reversibility test was performed using formoterol via a dry-powder inhaler (Aerolizer). Patients then received formoterol 12 microg twice daily until Visit 3 (Day 21-30), when a further formoterol FEV1 reversibility test was performed. Clinical parameters included FEV1, symptom questionnaires and rescue medication use. RESULTS: There was no significant relationship between the immediate change in FEV1 with salbutamol and the absolute change from baseline in FEV1, symptom scores or rescue medication use after a 4-week formoterol treatment. Relative immediate change in FEV1 with formoterol was correlated with change in rescue medication use (P = 0.02) and FEV1 at Visit 3 (P < 0.001). Total reversibility in FEV1 with formoterol (post-dose Visit 3-pre-dose Visit 2) was correlated with all treatment efficacy variables (P<0.01). CONCLUSIONS: Immediate salbutamol reversibility testing, as performed under these study conditions, failed to predict the clinical efficacy of formoterol. Total reversibility after 4 weeks of formoterol treatment may be a better predictor of clinical benefits of long-term bronchodilator therapy.     

Safety and tolerability of high-dose formoterol (Aerolizer) and salbutamol (pMDI) in patients with mild/moderate, persistent asthma

This double-blind, double-dummy, crossover study evaluated the tolerability of high-dose formoterol and salbutamol. Sixteen adults with mild/moderate persistent asthma (FEV1 > or = 70% predicted) were randomized to receive either formoterol 36 microg three times daily (TID) at 5-h intervals via Aerolizer (total daily dose 108 microg), or salbutamol 600 microg TID via pressurized metered-dose inhaler (total daily dose 1800 microg) for 3 consecutive days. After a 3-7-day washout period patients received the other treatment. FEV1 was measured 15 min pre-dose and 2 h post-dose. Both formoterol and salbutamol were associated with decreased plasma potassium (mean of minimum values: 3.4 and 3.6 mmol/L, respectively; P<0.001), increased serum glucose (mean of maximum values: 8.3 and 7.9 mmol/L, respectively; P=0.021), and small increases in mean QTc interval (mean of maximum values: 428.8 and 417.4 ms, respectively; P<0.001). However, none of these effects was clinically significant. Both treatments increased FEV1 to a mean maximum of 4.6 L (P=0.613), but the mean FEV1 AUC(0-72)h for formoterol was significantly greater than for salbutamol (302.2 L h, vs. 277.4 L h; P<0.001). No patients discontinued due to treatment-related adverse events. High-dose formoterol via Aerolizer did not produce any clinically significant systemic effects in patients with mild/moderate asthma.     

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 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.     

Safety and tolerability of high-dose formoterol (via Aerolizer) and salbutamol in patients with chronic obstructive pulmonary disease

To evaluate the safety and tolerability of high-dose formoterol and salbutamol in patients with chronic obstructive pulmonary disease (COPD). In this two-way crossover, double-blind, double-dummy study, 17 adults with mild-to-moderate COPD were randomized to receive either formoterol 24 microg (2 x 12 microg via Aerolizer), or salbutamol 600 microg (6 x 100 microg via metered-dose inhaler), and the appropriate double-dummy q.i.d. at 4-h intervals for 3 consecutive days (total daily dose: 96 and 2400 microg, respectively). After a 4-7-day washout period, patients were switched to the other treatment. Treatment with high-dose formoterol and salbutamol was equally well tolerated, with no reports of serious adverse events. Both agents were associated with decreased plasma potassium (mean minimum values: 3.4 and 3.3 mmol/l for formoterol and salbutamol, respectively; P=0.914), increased serum glucose (mean maximum values: 9.0 and 8.7 mmol/l, respectively; P=0.373), and small increases in mean QTc interval (mean maximum 439 ms with both treatments; P=0.813). No clinically relevant between-treatment differences in adverse events or laboratory values occurred. Both drugs improved lung function (mean maximum forced expiratory volume in 1s [FEV(1)] 2.6 l with both treatments; P=0.624), with the improvement being significantly greater with formoterol than with salbutamol on all 3 days of treatment (mean area under the curve [AUC](0-24 h) of FEV(1) formoterol vs. salbutamol on days 1-3, all P<0.05). High-dose formoterol via Aerolizer (up to 96 microg/day) has a comparable tolerability profile to that of salbutamol in patients with mild-to-moderate COPD.     

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.     

Improved lung function and symptom control with formoterol on demand in asthma.

Many asthma patients remain symptomatic despite maintenance therapy with inhaled corticosteroids (ICS) and salbutamol as rescue medication. In the present study the relative efficacy and preference for as-needed formoterol compared with salbutamol was examined. In total, 211 patients with a mean age of 45 yrs (mean forced expiratory volume in one second (FEV1) 77% predicted normal), using ICS, were randomised to 3 weeks' double-blind treatment with as-needed formoterol 4.5 microg Turbuhaler and with as-needed salbutamol 100 mug Turbuhaler in a cross-over fashion. Overall, lung function and symptom control were better with as-needed formoterol than with as-needed salbutamol. During as-needed formoterol treatment daytime and night-time symptom scores were lower, peak expiratory flow and FEV1 were higher and patients experienced fewer disturbed nights (34%) compared with as-needed salbutamol. Patients preferred the formoterol treatment to salbutamol. Of the 162 patients expressing a preference, formoterol was preferred by 68% (95% confidence interval: 60-75). Subjective assessment of effectiveness also favoured formoterol, which was perceived as slightly faster acting than salbutamol. In conclusion, as-needed formoterol improved symptoms and lung function compared with salbutamol and was perceived as more effective and at least as fast acting for symptom relief.     

Reversing acute bronchoconstriction in asthma: the effect of bronchodilator tolerance after treatment with formoterol.

Continuous treatment with a short-acting beta2-agonist can lead to reduced bronchodilator responsiveness during acute bronchoconstriction. This study evaluated bronchodilator tolerance to salbutamol following regular treatment with a long-acting beta2-agonist, formoterol. The modifying effect of intravenous corticosteroid was also studied. Ten asthmatic subjects (using inhaled steroids) participated in a randomised, double-blind, placebo-controlled, cross-over study. Formoterol 12 microg b.i.d. or matching placebo was given for 10-14 days with >2 weeks washout. Following each treatment, patients underwent a methacholine challenge to induce a fall in forced expired volume in one second (FEV1) of at least 20%, then salbutamol 100 microg, 100 microg, and 200 microg was inhaled via a spacer at 5 min intervals, with a further 400 microg at 45 min. After a third single-blind formoterol treatment period, hydrocortisone 200 mg was given intravenously prior to salbutamol. Dose-response curves for change in FEV1 with salbutamol were compared using analysis of covariance to take account of methacholine-induced changes in spirometry. Regular formoterol resulted in a significantly lower FEV1 after salbutamol at each time point compared to placebo (p<0.01). The area under the curves (AUCs) for 15 (AUC0-15) and 45 (AUC0-45) min were 28.8% and 29.5% lower following formoterol treatment (p<0.001). Pretreatment with hydrocortisone had no significant modifying effect within 2 h of administration. It is concluded that significant tolerance to the bronchodilator effects of inhaled salbutamol occurs 36 h after stopping the regular administration of formoterol. This bronchodilator tolerance is evident in circumstances of acute bronchconstriction.     

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.     

Randomised trial comparing as-needed versus regular treatment with formoterol in patients with persistent asthma

PURPOSE: The aim of this study was to demonstrate the equivalent efficacy of inhaled formoterol in asthmatic patients, either given as-needed or on a regular twice-daily schedule. METHODS: Randomised, open 12-week study in patients with mild to moderate asthma not adequately controlled with inhaled glucocorticosteroids alone. Patients received inhaled formoterol as needed or on a regular schedule (2x2 puffs/day with 6 microg formoterol per puff). Patients in the twice-daily formoterol group could use salbutamol as a rescue medication. The primary endpoint was the number of patients with asthma exacerbations in each group. RESULTS: Thirty-nine centres randomised 359 patients. The number of patients with asthma exacerbations showed neither a clinically relevant nor a statistically significant difference between groups: formoterol as-needed: 3.95% (7 of 177); twice daily: 3.45% (6 of 174). Patients in the formoterol as-needed group used significantly less formoterol (-1.5 puffs per day; P<0.0001). Including the saved rescue medication (up to one puff per day), total beta-2 agonist use in the formoterol as-needed group decreased by approximately 2-2.5 puffs per day. Both formoterol treatment schedules were well tolerated. Musculoskeletal pain and tremor were less frequent in the formoterol as-needed group: headaches were slightly more frequent. CONCLUSION: Formoterol given as needed and without additional beta-2 agonist, and formoterol given on a regular basis twice daily, supplemented by salbutamol as a rescue medication, appeared equally effective in this clinical study. Drug consumption was markedly lower in the former group.     

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.     

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.     

Tachyphylaxis to systemic but not to airway responses during prolonged therapy with high dose inhaled salbutamol in asthmatics

High doses of inhaled salbutamol produce substantial improvements in airway response in patients with asthma, and are associated with dose-dependent systemic beta-adrenoceptor responses. The purpose of the present study was to investigate whether tachyphylaxis occurs during prolonged treatment with high dose inhaled salbutamol. Twelve asthmatic patients (FEV1, 81 +/- 4% predicted), requiring only occasional inhaled beta-agonists as their sole therapy, were given a 14-day treatment with high dose inhaled salbutamol (HDS), 4,000 micrograms daily, low dose inhaled salbutamol (LDS), 800 micrograms daily, or placebo (PI) by metered-dose inhaler in a double-blind, randomized crossover design. During the 14-day run-in and during washout periods, inhaled beta-agonists were withheld and ipratropium bromide was substituted for rescue purposes. At the end of each 14-day treatment, a dose-response curve (DRC) was performed, and airway (FEV1, FEF25-75) chronotropic (HR), tremor, and metabolic (K, Glu) responses were measured at each step (from 100 to 4,000 micrograms). Treatment had no significant effect on baseline values. There were dose-dependent increases in FEV1 and FEF25-75 (p less than 0.001), and pretreatment with HDS did not displace the DRC to the right. DRC for HR (p less than 0.001), K (p less than 0.001), and Glu (p less than 0.005) were attenuated after treatment with HDS compared with PI. There were also differences between HDS and LDS for HR (p less than 0.001) and Glu (p less than 0.05) responses. Frequency and severity of subjective adverse effects were also reduced after HDS: tremor (p less than 0.001), palpitations (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

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.