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.     

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 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.     

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.     

Equivalent therapeutic ratio of salbutamol given by Turbuhaler and Diskus

Some inhalers have been claimed to give better deposition, resulting in higher efficacy. In a previous study we did not find any evidence of different potency of salbutamol given either via pMDI or Turbuhaler. The aim of the present study was to compare the efficacy and safety of salbutamol given via Diskus or Turbuhaler. Twenty-five asthmatics with step-wise reversible airflow obstruction (total reversibility of at least 15%) were included in a randomized, double-dummy, placebo-controlled cross-over study. On each study day, the patients were given placebo repeatedly, or cumulative doses of 200, 400, 800, 1600 and 3200 microg salbutamol given via either device (double-blind, placebo-controlled). Salbutamol caused a dose-related increase in FEV1 when given by Diskus or Turbuhaler. The improvement in FEV1 was similar regardless of whether salbutamol was given via Diskus or Turbuhaler, at equivalent microgram doses. After a total cumulative dose of 3200 microg, mean FEV1 for Diskus was 2.46 l (change from baseline of 20.5%), for Turbuhaler 2.50 l (change from baseline 24.6%) and for placebo 2.11 l (3% change from baseline). After correcting for different baseline differences, the percentage difference between Diskus and Turbuhaler was -1.8% (P = 0.2). Systemic effects (potassium and heart rate) did not differ between Diskus or Turbuhaler. We conclude that the efficacy of salbutamol given at equivalent microgram doses, as well as side-effects, are comparable when the drug is given via Diskus or Turbuhaler. The present data shows that salbutamol given by these devices have similar therapeutic ratios.     

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.     

Clinical equivalence between salbutamol hydrofluoroalkane pMDI and salbutamol Turbuhaler at the same cumulative microgram doses in paediatric patients

This study aimed to demonstrate equivalent efficacy and safety between salbutamol delivered via the HFA134a pMDI (Hydrofluoroalkane 134a pressurised Metered Dose Inhaler) and the Turbuhaler dry powder inhaler in asthmatic children. This was a randomised, double-blind, double-dummy, placebo-controlled, crossover study in 10 asthmatic children aged 6-15 years who demonstrated at least 10% reversibility of FEV1 after inhaling 400 microg of salbutamol. On 5 single study days subjects received either placebo or cumulative doses of 100, 200, 400 and 800 microg of salbutamol at 30 minute intervals. Both devices were placebo on one study day while each device was active on two study days. FEV1 was measured before and 20 minutes after each dose. Heart rate was measured before spirometry. Mean FEV1 and heart rate at each time point and the area under the dose response time curve (AUC) were analysed using ANOVA. FEV1 increased similarly after cumulative doses of salbutamol on each of the study days, irrespective of device. Mean treatment difference in AUC was 0.01 L. min (95%CI -0.05 to 0.08 L). Heart did not differ at any dose. It is concluded that salbutamol delivery from a HFA pMDI and Turbuhaler is equivalenton a microgram basis in asthmatic children for efficacy and safety.     

Efficacy and safety of budesonide/formoterol compared with salbutamol in the treatment of acute asthma

This study compared the efficacy and safety of budesonide/formoterol (Symbicort) Turbuhaler)) with salbutamol pressurized metered-dose inhaler (pMDI) with spacer for relief of acute bronchoconstriction in patients with asthma. In this randomized, double-blind, parallel-group study, patients (n = 104 allocated to treatment; n = 103 received treatment; mean age 45 years) seeking medical attention for acute asthma (mean FEV(1) 43% of predicted) received two doses repeated at t = -5 and 0 min of either budesonide/formoterol (320/9 microg, two inhalations) or salbutamol (100 microg x eight inhalations); total doses 1280/36 microg and 1600 microg, respectively. All patients received prednisolone 60 mg at 90 min and FEV(1) was assessed over 3h. FEV(1) 90 min after dosing (primary variable) increased compared with pre-dose FEV(1) by an average of 30% and 32% for budesonide/formoterol and salbutamol, respectively (P = 0.66), with similar increases at all timepoints from 3 to 180 min for both groups. Mean pulse rate over 3h was significantly higher in the salbutamol group versus the budesonide/formoterol group (92 vs. 88 bpm; P < 0.01). No treatment differences were seen for other vital signs, including ECG. High-dose budesonide/formoterol was effective and well tolerated for the treatment of acute asthma, with rapid onset of efficacy and a safety profile over 3h similar to high-dose salbutamol.     

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.     

Efficacy of formoterol Turbuhaler in the emergency treatment of patients with obstructive airway diseases

Dry powder devices are rarely used in the emergency room (ER) treatment of acute and severe bronchoconstriction due to hesitations with respect to clinical efficacy. This study investigated the effects of two inhalers with formoterol in patients visiting the ER Department for acute and severe dyspnoea, mainly exacerbations of chronic obstructive pulmonary disease. Two doses of 12mug formoterol were given at enrolment, either via Turbuhaler or via pressurised metered dose inhaler, connected to a spacer device (pMDI+S) in a double-blind way and parallel design. Another two doses of 12 microg formoterol were given after 30 min. Forced expiratory volume in the 1s (FEV(1)) and Borg dyspnoea score were assessed until 60 min. The study was designed to test non-inferiority in effects on FEV(1). Seventy-seven patients were enrolled with a mean age of 66 years and a FEV(1) of 1.03 L (39% of predicted). The effects of the two treatments were almost identical. The mean improvement in FEV(1) at 60 min after formoterol Turbuhaler was 94% of the improvement after formoterol pMDI+S. A statistically significant non-inferiority was shown (p=0.037) at 60 min (primary endpoint) as well as at 5 and 30 min (secondary endpoints, p=0.0043 and 0.013, respectively). Improvements in the Borg dyspnoea score and other lung-function parameters did not differ significantly between the two devices. In conclusion, formoterol Turbuhaler was equally effective as formoterol pMDI+S in the treatment of acute bronchoconstriction within the ER.     

Comparison of formoterol, salbutamol and salmeterol in methacholine-induced severe bronchoconstriction.

The onset of the bronchodilating effect of formoterol (12 microg by Turbuhaler) was compared with that of salbutamol (50 microg by Turbuhaler), salmeterol (50 microg by Diskhaler) and placebo in methacholine-induced severe bronchoconstriction. Seventeen subjects with mild-to-moderate asthma completed this randomized, double blind, cross-over, double-dummy study. On four study days, baseline forced expiratory volume in one second (FEV1) was recorded and the subjects were challenged with methacholine until FEV1 fell by at least 30%. Immediately thereafter, the study drugs were inhaled and lung function was assessed for 60 min. The geometric mean time for FEV1 to return to 85% of baseline was 7.2 min with formoterol, 6.5 min with salbutamol, 14.1 min with salmeterol and 34.7 min with placebo (p=0.0001, overall ANOVA). The difference between formoterol and salmeterol was statistically significant (p=0.01); there was no difference between formoterol and salbutamol (p=0.69). In conclusion, formoterol reversed methacholine-induced severe bronchoconstriction as rapidly as salbutamol and more rapidly than salmeterol. Classifying beta2-agonists as "fast"- and "slow"- acting may be supplemental to "short"- and "long"-acting.     

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.     

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.     

Onset of bronchodilation of budesonide/formoterol vs. salmeterol/fluticasone in single inhalers

Combinations of inhaled glucocorticoids and long-acting beta2-agonists in the same inhaler device have become available in recent years. In this double-blind, randomized, placebo-controlled and crossover study we have evaluated the onset of action of budesonide and formoterol in a single inhaler (Symbicort Turbuhaler) and that of the fixed combination of salmeterol and fluticasone (Seretide Diskus). Thirty patients with a mean FEV1 of 2.54 l (range: 1.48-4.28) and a mean inclusion reversibility in FEV1 of 19.1% were included. Single doses of budesonide/formoterol 160/4.5 microg and 2x (160/4.5) microg, salmeterol/fluticasone 50/250 microg, or placebo were given. Serial measurements of FEV1 were performed over 3 h. The combination of one or two inhalations of budesonide/formoterol showed a faster onset of action than salmeterol/fluticasone, both evaluated as mean FEV1 at 3 min (2.74, 2.75 and 2.56 l respectively P<0.001 for both doses of budesonide/formoterol), or as average FEV1 from 0 to 15 min (2.80, 2.83 and 2.67 l respectively P<0.001 for both doses of budesonide/formoterol). For placebo, mean FEV1 at 3 min was 2.46 l, and the average FEV1 at 0-15 min was 2.50 l. Furthermore, budesonide/formoterol at both doses resulted in higher FEV1 than salmeterol/fluticasone at 3 h. We conclude that the combination of budesonide/formoterol has a faster onset of action than salmeterol/fluticasone.     

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.     

The efficacy of a new salbutamol metered-dose powder inhaler in comparison with two other inhaler devices

An open cross-over and randomized study was carried out in order to compare the efficacy and safety of inhaled salbutamol delivered from a new 50 microg dose(-1) metered-dose dry powder inhaler Taifun, and a commercially available 50 microg dose(-1) dry powder inhaler Turbuhaler, and a conventional 100 microg dose(-1) pressurized metered-dose inhaler with a spacer (pMDI+S). Twenty-one patients, aged 21-70 years, with stable asthma and with demonstrated reversibility upon inhalation of salbutamol were included in the study. On three separate study days, the patients received a total dose of 400 microg of salbutamol from the dry powder inhalers and a dose of 800 microg from the pMDI+S in a cumulative fashion: 1,1, 2 and 4 doses at 30 min intervals. The percent change in forced expiratory volume in 1 sec (FEV1), was used as the primary efficacy variable. Salbutamol inhaled via the Taifun produced greater bronchodilation than the other devices. The difference in percent change in FEV1 between the Taifun and the other devices was statistically significant at the two first dose levels, but diminished towards the higher doses when the plateau of the dose-response curve was reached. The estimated relative dose potency of the Taifun was approximately 1.9- and 2.8-fold compared to the Turbuhaler and the pMDI+S, respectively. The Taifun caused a slight, but clinically insignificant, decrease in serum potassium concentration. There were no significant changes in the other safety parameters (blood pressure, heart rate and electrocardiogram recordings) with any of the used devices. In conclusion, this study indicates that salbutamol inhaled via the Taifun is more potentthan salbutamol inhaled from the other devices tested. In practise, a smaller total dose of salbutamol from theTaifun is needed to produce a similar bronchodilatory response. All treatments were equally well tolerated.     

Efficacy and safety of formoterol Turbuhaler when added to inhaled corticosteroid treatment in children with asthma

This double-blind, placebo-controlled, randomized, parallel-group, multicenter study was conducted in 302 children aged 6-11 years with asthma not optimally treated with inhaled corticosteroids alone. Patients continued with their existing dose of inhaled corticosteroids and in addition received placebo, formoterol 4.5 microg or formoterol 9 microg b.i.d., for 12 weeks (all delivered via Turbuhaler). Terbutaline was available as reliever medication. The primary efficacy variable was change from baseline in morning peak expiratory flow (PEF); secondary efficacy variables included forced expiratory volume in 1 sec (FEV(1)), serial PEF measured over 12 hr, evening PEF, asthma symptom score, and quality of life. Compared with placebo, formoterol 4.5 microg and 9 microg improved morning PEF by 8 l/min (P = 0.035) and 11 l/min (P = 0.0045), respectively. Evening PEF and FEV(1) were also significantly increased compared with placebo, with no statistically significant difference between formoterol doses. Lung-function improvements compared with placebo were greater in the middle of the day. Twelve-hour average serial PEF after 3 months increased by 24 l/min (95% CI, 9, 39 l/min) in the formoterol 9-microg group, and by 14 l/min (95% CI, 0, 29 l/min) in the formoterol 4.5-microg group. The incidence of severe exacerbations in both formoterol groups was numerically lower than in the placebo group, indicating that formoterol may have the potential to improve exacerbation control in children. Both formoterol doses were well-tolerated, and tolerance to the drug's bronchodilator effect was not observed. Formoterol provided sustained improvements in lung function and was well-tolerated in children with asthma suboptimally treated with inhaled corticosteroids alone.     

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.     

Lung deposition and efficacy of inhaled formoterol in patients with moderate to severe COPD

BACKGROUND: Little is known about the impact of COPD on lung deposition of inhaled drugs and the relationship between lung-dose and response of pulmonary function measurements. METHODS: Nineteen patients with varying degrees of COPD were randomized to inhale single doses of formoterol (Oxis) Turbuhaler 4.5, 9, 18, and 36 microg in a double blind, placebo-controlled, crossover design. Urinary excreted formoterol during 32 h was used to determine absolute lung deposition. Peak inspiratory flow (PIF) and inhaled volume (IV) were recorded to assess the patients' ability to use Turbuhaler. Efficacy was measured by spirometry, inspiratory capacity (IC), airway conductance (sG(AW)), and absolute lung volumes. RESULTS: Mean pulmonary bioavailability of formoterol was about 24% of the nominal delivered dose after inhalation for the different treatments. No significant correlations between lung deposition and baseline FEV(1), PIF or IV were shown. All formoterol doses produced statistically significant increases in FEV(1), FVC, IC, and sG(AW) relative to placebo. Linear dose/response relationships were observed for these variables, with more narrow limits of the slopes for the lung-dose/response relationships than for the nominal-dose/response relationships. Moreover, 36 and 18 microg formoterol statistically significantly decreased functional residual capacity (FRC) and residual volume (RV) relative to placebo. CONCLUSIONS: This study could not show any difference in lung deposition of formoterol inhaled via Turbuhaler between patients with moderate and severe COPD. Moreover, the effect of formoterol on various pulmonary function measurements were more closely related to lung deposition than the inhaled nominal dose.     

Bronchodilator response to albuterol after regular formoterol and effects of acute corticosteroid administration

BACKGROUND: There is controversy about the development of bronchodilator subsensitivity after regular administration of long-acting beta(2)-agonists. OBJECTIVES: The purpose of the study was to evaluate whether regular treatment with formoterol affects the bronchodilator response to repeated puffs of albuterol, and also to assess the effects of acute administration of a bolus dose of IV or inhaled corticosteroid. MATERIALS AND METHODS: Twelve patients (mean [SD] age, 43 [15] years; FEV(1), 57 [17] % predicted) with stable, moderate to severe persistent asthma who were all taking inhaled corticosteroids were evaluated in a randomized, placebo-controlled, double-blind, double-dummy, crossover study. Patients received treatments each for 2 weeks followed by a bolus (IV/inhaled) of corticosteroid or placebo: (1) placebo inhaler bid + bolus placebo; (2) formoterol Turbuhaler 24 microg metered dosage bid (delivered dosage 18 microg bid) + placebo; (3) formoterol 24 microg bid + bolus IV hydrocortisone, 200 mg; or (4) formoterol 24 microg bid + bolus inhaled budesonide, 1,600 microg. Bronchodilator response to repeated puffs of albuterol (200 to 1,600 microg) for > 80 min was measured at 2 h after bolus administration of placebo or corticosteroid. The study was powered at the 80% level to detect a 20% difference in area under curve between 20 and 80 min (AUC) for FEV(1) response to albuterol as change from baseline (primary end point). RESULTS: There was significant subsensitivity (p = 0.01) of the mean albuterol FEV(1) response (as AUC, L x s) after formoterol alone (737) as compared to placebo (1,453) along with partial reversal by steroid administration: formoterol + hydrocortisone (1, 050), and formoterol + budesonide (942). There was a similar pattern of subsensitivity (p = 0.03) for the mean albuterol forced expiratory flow between 25% and 75% of vital capacity response (as AUC, L): placebo (2,149), formoterol alone (1,002), formoterol + hydrocortisone (1,402), and formoterol + budesonide (1,271). CONCLUSION: Regular treatment with formoterol produced significant bronchodilator subsensitivity to repeated puffs of albuterol, which was partially reversed by a bolus dose of systemic or inhaled corticosteroid.