Usefulness of HFA-BDP for adult patients with bronchial asthma: randomized crossover study with fluticasone

Patient-reported outcomes in clinical trials of inhaled asthma medications: systematic review and research needs

PURPOSE

To assess the diversity, application, analysis and interpretation of patient-reported outcomes (PROs) in asthma clinical trials.

METHODS

We critically appraised the use of asthma-specific PROs in 87 randomised controlled trials (RCTs) of inhaled asthma medications published during 1985-2006.

RESULTS

A total of 79 RCTs reported PROs, of which 78 (99%) assessed symptom scores and seven (9%) assessed asthma quality of life scores. Only eight (10%) used validated instruments and five (6%) provided clinical interpretation of scores. Due to heterogeneity in the reporting of symptom measures, it is not possible to determine how many discrete symptom assessment instruments have been used. Only 26 (33%) of the RCTs that measured symptom scores reported the scores for follow-up. Limited improvement occurred over time: fewer than 30% of the RCTs used validated PRO measures in any individual year.

CONCLUSION

Numerous validated PRO instruments are available but it is unclear why few are used in asthma clinical trials. Problems include poor reporting, and uncritical analysis and interpretation of PRO scores. Research needs include identifying and recommending a set of PROs for use in asthma clinical research and providing guidance for researchers on the application, analysis and interpretation of PRO measures in clinical trials.

Comparison of inhaled corticosteroids: an update

OBJECTIVE

To review the basis for the estimated comparative daily dosages of inhaled corticosteroids for children and adults that are presented in the National Heart, Lung, and Blood Institute's Expert Panel Report 3; in addition, the pharmacodynamic and pharmacokinetic basis for potential clinical differences among inhaled corticosteroids is discussed.

DATA SOURCES

A complete MEDLINE search was conducted of human studies of asthma pharmacotherapy published between January 1, 2001, and March 15, 2006, followed by a PubMed search up until August 2008, using ciclesonide, inhaled corticosteroids, and pharmacokinetics as key words. Product information on each inhaled corticosteroid was also included.

STUDY SELECTION AND DATA EXTRACTION

Comparative clinical trials of inhaled corticosteroids and systematic reviews for efficacy comparisons were evaluated. Extensive literature reviews, meta-analyses, and selected clinical studies that illustrate or represent specific points of view were selected. Pharmacodynamic and pharmacokinetic data extracted from previously published reviews and specific studies were included.

DATA SYNTHESIS

Pharmacodynamic characteristics (glucocorticoid receptor binding) and lung delivery determine the relative clinical efficacy and pharmacokinetic properties (oral bioavailability, lung retention, systemic clearance) and determine comparative therapeutic index of the inhaled corticosteroids. Secondary pharmacokinetic differences (intracellular fatty acid esterification, high serum protein binding) that have been posited to improve duration of action and/or therapeutic index are unproven, and current comparative clinical trials do not support the hypotheses that they provide an advantage. Ultrafine particle meter-dose inhalers (MDIs) have not demonstrated superior asthma control or improved safety over older MDIs. All of the inhaled corticosteroids demonstrate efficacy with once-daily dosing, and all are more effective when dosed twice daily.

CONCLUSIONS

Current evidence suggests that all of the inhaled corticosteroids have sufficient therapeutic indexes to provide similar efficacy and safety in low to medium doses. Whether or not some of the newer inhaled corticosteroids offer any advantages at higher doses has yet to be determined.

Fluticasone versus HFA-beclomethasone dipropionate for chronic asthma in adults and children

BACKGROUND

The relative efficacy of fluticasone (FP) and beclomethasone (BDP) propelled with CFCs has been well established. The potency of HFA-BDP is thought to have been improved with new propellant and some studies suggest that it may equipotent at half the dose of CFC propelled-BDP. There is a need to revisit this question in the light of a potentially more potent new non-CFC propellant.

OBJECTIVES

To determine the relative efficacy of FP and HFA-propelled BDP in chronic asthma.

SEARCH STRATEGY

The Cochrane Airways Group Specialised Register was searched using pre-specified terms. Searches were current as of January 2006.

SELECTION CRITERIA

Randomised controlled trials were eligible for inclusion in the review. We compared either CFC or HFA-propelled FP with HFA-propelled BDP. We made a distinction between HFA-BDP and HFA-BDP extra fine, which dispenses smaller particles of drug, leading to different, usually more peripheral distribution in the airways. Any inhaler device was considered, and there was no restriction on studies with or without spacers. We included studies which assessed HFA-BDP given via either pMDI, breath-actuated MDI, or DPI.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed studies for inclusion in the review. Data were extracted and entered in to RevMan 4.2 using standard meta-analytical techniques with predefined criteria for exploring statistical heterogeneity.

MAIN RESULTS

Eight studies (1260 participants) met the inclusion criteria of the review. One study was conducted in children. Study reporting quality was fair, but all studies were of short duration (three to twelve weeks). Only studies assessing HFA-BDP extra fine in comparison with FP were identified. Lung function was not significantly different between extra fine BDP and FP when compared at the same dose in parallel studies, change in FEV1: 0.04 litres (95% CI -0.03 to 0.11 litres; three studies, 659 adults); change in am PEF: -0.69 litres (95% CI -11.21 to 9.83 litres; two studies, 364 adults). Individual studies reported non-significant findings in symptom scores and quality of life questionnaires. There was no significant difference between FP and HFA-BDP in the risk of study withdrawal, dysphonia or when data were reported as any adverse event.

AUTHORS' CONCLUSIONS

There was no significant difference between FP and extra fine HFA-BDP on FEV(1) or peak flow at a dose ratio of 1:1. However, the number of studies and width of the confidence intervals in the analyses do not exclude a clinically meaningful difference between these two drugs. Difficulty in the successful manipulation of the devices studied may be a barrier to the widespread use of MDIs. One paediatric study was included in the review, so extrapolation of the findings of this review to children is limited. Further longer term studies in adults and children with moderate and severe asthma are required.