Copyright ©ERS Journals Ltd 2007 Indacaterol, a novel inhaled ß2-agonist, provides sustained 24-h bronchodilation in asthma1 insaf Respiratory Research Institute, Wiesbaden, and 3 Pulmonary Research Institute, Hospital Grosshansdorf, Hamburg, Germany. 2 Dept of Respiratory Diseases, Ghent University Hospital, Ghent, Belgium. 4 Novartis Horsham Research Centre, Horsham, UK. 5 Pulmonary and Critical Care Medicine, Drexel University College of Medicine, Philadelphia, PA, USA. CORRESPONDENCE: K. M. Beeh, insaf Respiratory Research Institute, Biebricher Allee 34, D-65187 Wiesbaden, Germany. Fax: 49 6119854348. E-mail: k.beeh{at}insaf-wi.de Keywords: Asthma, bronchodilators, forced expiratory volume in one second, indacaterol, long-acting ß2-agonist, once-daily
Received: May 5, 2006
The present study examined the bronchodilator and safety profiles of single-dose indacaterol in intermittent or persistent asthma. In the present double-blind crossover study, 42 patients were randomised to receive single doses of indacaterol (50, 100, 200 and 400 µg) or placebo via a hydrofluoroalkane pressurised metered-dose inhaler. The primary efficacy comparisons were the per cent changes in forced expiratory volume in one second (FEV1 ) between indacaterol and placebo 30 min and 21 h post-dose. All doses resulted in prolonged bronchodilation, with indacaterol 200 and 400 µg meeting pre-specified efficacy criteria. The mean percentage increases in FEV1 from placebo with indacaterol 200 and 400 µg were 7.6 and 14.9%, respectively, at 30 min, and 7.5 and 10.4%, respectively, at 21 h post-dose. At these doses, changes in mean FEV1 relative to placebo were statistically significant from 5 min to 25 h, inclusive. At 5 min, the geometric least squares mean values for FEV1 were 3.08 and 3.22 L for the 200 and 400 µg doses, respectively, compared with 2.99 L for placebo. At 24 h after dosing, the baseline-adjusted geometric least square mean FEV1 was 3.13, 3.11, 3.24 and 3.30 L for indacaterol 50, 100, 200 and 400 µg, respectively, and 2.98 L for placebo. All treatments were well tolerated. Once-daily indacaterol at doses of 200 and 400 µg provided sustained 24-h bronchodilation, with a rapid onset and a good tolerability and safety profile. Inhaled ß2-adrenoceptor agonists are the most effective bronchodilators for the management of asthma 1. The Global Initiative for Asthma guidelines recognise the role of long-acting ß2-agonists (LABAs) for the optimal treatment of moderate-to-severe persistent asthma 1. Currently available inhaled LABAs have durations of action of 12 h at recommended doses, necessitating twice-daily dosing to provide optimal clinical efficacy 25. The availability of a once-daily ß2-agonist could be expected to improve the treatment of asthma by providing patients with greater convenience and sustained bronchodilation.
Indacaterol is a ß2-agonist bronchodilator in development for the treatment of asthma and chronic obstructive pulmonary disease (COPD). Pharmacologically, indacaterol is a nearly full ß2-agonist with a high intrinsic efficacy and, unlike partial agonists, it does not exhibit antagonistic behaviour in the presence of isoprenaline 6. Multiple-dose, dose-ranging studies 7, 8 in patients with asthma have shown that indacaterol provides effective bronchodilation with fast onset of action (within 5 min), which is sustained for The aim of the current study was to examine the bronchodilator profile of a range of indacaterol doses in patients with intermittent or persistent asthma.
Design The present study was a multicentre, randomised, double-blind, placebo-controlled, crossover, dose-ranging study. Patients were randomised to one of five crossover treatment sequences (Latin square design) to inhale a single dose of indacaterol 50, 100, 200 or 400 µg or placebo from a hydrofluoroalkane (HFA) pressurised metered-dose inhaler (pMDI), with a 514 day washout between treatment periods. At all treatment visits, patients were under continuous medical supervision from the first pre-dose evaluation until 26 h after administration of the study medication. Study medication was administered between 17:00 and 19:00 h and patients were allowed to sleep for 7 h, approximately between 00:0007:00 h. The study received institutional review board approval and all patients gave informed written consent prior to the start of the study. The study was conducted according to Good Clinical Practice guidelines and in accordance with the Declaration of Helsinki (1964 and subsequent revisions).
Inclusion and exclusion criteria Exclusion criteria were: 1) the presence of relevant pulmonary disease; 2) use of tobacco products within 6 months before screening or a smoking history of >10 pack-yrs; 3) hospitalisation or emergency room treatment for acute asthma in the 3 months prior to screening or between screening and the start of the treatment period; 4) a respiratory tract infection within 1 month prior to screening; 5) abnormal blood glucose levels; and 6) corrected QT (QTc) interval at screening >430 or 450 ms for males and females, respectively, or a history of prolonged QTc interval.
Study treatment
Inhaled salbutamol was only permitted as rescue medication and was not to be taken within 6 h prior to the start of a treatment period. If rescue salbutamol was needed during this period, the visit was rescheduled. Patients taking ICS ( Treatments not permitted included fixed combinations of ß2-agonists and ICS, parenteral or oral corticosteroids, theophylline or other xanthines, leukotriene antagonists, and oral or inhaled anticholinergics.
Assessments Secondary efficacy comparisons with placebo (both per cent and absolute change) included the standardised areas under the curve (AUC) for FEV1 06 h, 1324 h and 024 h post-dose. A summary table for FEV1 at all time-points is also provided together with ANCOVAs assessing treatment ratios in FEV1 at each post-dose time-point. Safety was assessed by monitoring and recording all adverse events, serious adverse events, haematology, blood chemistry, urinalysis, vital signs, ECGs, spirometry and physical examination.
Statistical analyses The primary comparisons were performed using an ANCOVA model for log(FEV1), with patient as a random effect, period and treatment as fixed effects and log(baseline FEV1) as covariate. If patients took rescue medication prior to the 30-min post-dose evaluation, this value was excluded from the analysis. If a patient took rescue medication or withdrew 1321 h post-dose, the 21-h value was derived using last observation carried forward. However, the 21-h measurement was used in the analysis if it was lower than the last pre-rescue measurement. If a patient withdrew from the study prior to the 13-h post-dose evaluation, the 21-h value was not derived. For either time-point, data missing for any other reason were imputed using linear interpolation. ANCOVAs, similar to those used for the primary comparisons, were used for each of the AUC comparisons with no adjustment for multiplicity.
Sample size calculation
Establishing optimal dose
Patients The present study was carried out at three locations. A total of 50 patients were screened and 42 were randomised, all receiving at least one dose of study medication. Their demographics are shown in table 1
In total, 40 (95%) patients completed all five treatments in the study. One patient discontinued due to protocol violation (out of range FEV1 at pre-dose spirometry), and one, who later reported a previous history of a minor abnormality in a liver function test, due to mildly elevated bilirubin levels (suspected Gilbert's syndrome).
Efficacy
FEV1 at each post-dose time-point is shown both as a summary table (table 2
Analysis of standardised AUC for FEV1 at 06, 1324 and 024 h (table 4
Safety and tolerability All doses of indacaterol were well tolerated, with no serious adverse events experienced in any treatment sequence. The overall number of adverse events appeared to be dose-related (table 5
Haematological and biochemical measurements fell within the normal ranges and, with one exception, there were no clinically significant differences between treatments. One patient who had abnormally high values of creatinine kinase at the screening visit also had marked increases 6 h post-dose whilst receiving indacaterol 100 µg, although the values returned to normal 1326 h post-dose. The incidence of newly occurring biochemical abnormalities was low, with no clinically meaningful differences across treatments. There were minimal changes in mean potassium and glucose levels 6 h post-dose, with no statistically significant or clinically meaningful differences between treatments (table 6
There were no clinically significant differences in vital signs, including cardiac frequency and blood pressure, or ECG abnormalities between treatments. For all treatments, the QTc interval decreased from pre-dose to 15 min post-dose, with only minor changes at 6 and 24 h post-dose. There were no clinically meaningful or statistically significant differences in mean QTc interval between indacaterol and placebo. No QTc interval increases >60 ms from pre- to post-dose were observed.
The present study demonstrates that indacaterol provides sustained 24-h bronchodilation when taken once daily. During the current study, indacaterol was administered in the late afternoon (17:0019:00 h), at a time when the upswing of diurnal variation in FEV1 would have already occurred. Despite this, a rapid and sustained increase in FEV1 was observed, with the rapid onset of action of indacaterol (within 5 min of dosing) comparable to that of the SABA salbutamol ( 23 min) 14. In the present study, the first time-point (30 min post-dose) for one of the primary efficacy comparisons (% change in FEV1 from placebo) was selected on the basis of the characteristics of salmeterol, which has a relatively slow onset of action, achieving a clinically meaningful effect at 30 min post-dose 14. Therefore, the 30-min time-point was used to assess whether indacaterol was at least as fast in onset as salmeterol. The second time-point for comparison (21 h post-dose) was selected as this was considered to be the minimum requirement for a single dose of a drug that was to be given once a day.
All doses and placebo displayed a similar overnight decrease in FEV1, as can be seen from the 6 and 13 h measurements in figure 2 The lung function data in the present study demonstrate that there is a dose-dependent upward shift of the circadian pattern over the entire 26-h period in which FEV1 was measured. Despite the preservation of the circadian pattern, indacaterol doses provided trough FEV1 values (i.e. 2124 h post-dose) that were superior to placebo. This confirms the sustained 24-h bronchodilator efficacy of indacaterol, although only the 200 and 400 µg doses were statistically superior to placebo at all time-points from 5-min to 24-h post-dose. Since FEV1 for all doses of indacaterol was greater than placebo at all time-points, this provides evidence that the duration of action of indacaterol is dose-independent across the range tested and it may possibly be due to an intrinsic property of the molecule at the receptor level. Besides indacaterol, other once-daily LABAs are being developed 19. The convenience of once-daily dosing, together with sustained bronchodilation, will allow for better compliance, thus increasing the likelihood of medication adherence and asthma control. Improved clinical outcomes associated with prolonged bronchodilation have previously been shown when comparing twice-daily LABAs with regular SABA therapy 20, 21. In COPD, once-daily tiotropium is clearly superior to regular short-acting anticholinergic therapy for all relevant clinical outcomes 22. Alongside the potential advantages of a once-daily LABA, one also needs to consider that the regular use of LABAs has been linked with the potential development of tolerance to bronchoprotective and bronchodilator effects. The pharmacological profile may favour indacaterol in this respect. In pre-clinical studies (relative to isoprenaline) indacaterol (73%) has more of a full agonist profile than the partial agonist salmeterol (38%) 23, 24 and, therefore, might be expected to incur fewer problems of cross-tolerance to SABA rescue medication. Clinical studies to investigate these interactions, as well as the potential for receptor down-regulation in humans, have still to be carried out. The regular use of the LABA salmeterol without concomitant anti-inflammatory treatment has been associated with an increased risk of asthma death 25. The combination of LABA and ICS is currently considered as the gold standard for patients with moderate-to-severe persistent asthma 1. Thus, it is anticipated that a once-daily LABA will be recommended to be combined with a once-daily ICS, e.g. ciclesonide or mometasone, either in free or fixed combination. A rapid onset of action of the bronchodilator component (as shown for indacaterol) in such combinations might be beneficial since it would also allow for use in acute situations, a strategy that has been successfully developed for fixed combinations of budesonide/formoterol 26, 27. Experiments using indacaterol in isolated human bronchus have demonstrated an onset of effect very similar to those of formoterol and salbutamol, the classic rescue bronchodilator, in contrast to a more than two-fold slower onset for salmeterol 24. Finally, another possible future use would be to combine treatment with a once-daily LABA with once-daily tiotropium (or other once-daily anticholinergic) in COPD. With distinct but complementary pharmacological modes of action 28, such a combination would be likely to provide additional therapeutic benefits in this indication 29.
Since the present study was limited to several single-dose exposures separated by In conclusion, single 200 and 400 µg doses of indacaterol provided effective and sustained 24-h bronchodilator control with a rapid onset of action (<5 min) and a good tolerability and safety profile. The convenience of once-daily dosing could lead to better compliance and may help to treat both daytime and nocturnal symptoms of asthma.
The authors would like to acknowledge the contribution of the following investigators: R. Pauwels (Ghent, Belgium) and L. Grönke (Hamburg, Germany). In addition, the authors acknowledge the contribution of all of the other personnel involved in the study. The authors were assisted by professional medical writers D. Young, P. Birch and S. Filcek in the preparation of this text. The present study was supported by a grant from Novartis Pharma AG (Basel, Switzerland). K.M. Beeh received compensation for serving on an advisory board for Novartis, Germany. He has participated as a speaker in scientific meetings or courses organised and financed by various pharmaceutical companies (Boehringer, Novartis, Pfizer, Fujisawa, Merck, Sharpe & Dohme) in 2003, 2004 and 2005. He received fees for speaking at a conference symposium sponsored by Novartis in 2005. The institution where K.M. Beeh is currently employed has received compensations for participating in multicentre trials in 2004, 2005 and 2006 from several companies (AstraZeneca, Boehringer, Novartis, GlaxoSmithKline, Revotar, Biopharmaceuticals, EpiGenesis, Corus Pharma, Almirall Prodesfarma, Merck Sharpe & Dohme and Fujisawa). K.M. Beeh has been reimbursed for travel expenses by Novartis, Boehringer, Merck Sharp & Dohme and Pfizer for attending several conferences. E. Derom received grants in 2002, 2003 and 2004 for serving on an advisory board for GlaxoSmithKline. He also received compensation during 20032005 from Altana Pharma, GlaxoSmithKline, SGSBiopharma and Novartis as research grants for participating in clinical trials. E. Derom also received a grant from AstraZeneca to attend the American Thoracic Society 2004 Congress and from Altana Pharma to attend the European Respiratory Society 2005 Congress. F. Kanniess has received compensation for the conduct of clinical trials or educational grants from GSK, Epigenesis, Altana, AstraZeneca, Allmiral Prodesfarma, Boehringer Ingelheim, Schering-Plough, Astellas and ONO. R. Cameron has been employed by Novartis since April 1996. M. Higgins has been employed by Novartis since November 2001 and holds shares in the company. At the time of the study and development of the manuscript A. van As was a full-time employee of Novartis and owned stock in the company.
This article has been cited by other articles:
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||