Lung deposition of hydrofluoroalkane-134a beclomethasone is greater than that of chlorofluorocarbon fluticasone and chlorofluorocarbon beclomethasone : a cross-over study in healthy volunteers

Small airway involvement in severe asthma: how common is it and what are its implications?

Asthma is a prevalent chronic respiratory disease affecting all age groups globally, causing significant morbidity and mortality. Small airway involvement, often undetected by traditional spirometry, has emerged as a critical aspect of asthma pathophysiology, especially in severe cases. This retrospective observational study aimed to assess small airway dysfunction using impulse oscillometry (IOS) in 94 severe asthma patients. Results indicated that 27.3% of patients had small airway obstruction. While spirometry showed no statistical differences between groups, IOS parameters were significantly different, highlighting its sensitivity in detecting small airway disease. Patients with small airway involvement exhibited poorer asthma control, emphasizing the clinical relevance of identifying and addressing small airway dysfunction. The study underscores the need for comprehensive evaluation tools like IOS alongside spirometry, especially in severe asthma management. Further large-scale studies are warranted to validate IOS's utility in optimizing therapeutic strategies and improving asthma control, particularly in resource-limited settings. Recognizing and addressing small airway involvement could lead to individualized management approaches and better outcomes in severe asthma patients.

Small airways in asthma: From inflammation and pathophysiology to treatment response

Small airways are characterized as those with an inner diameter less than 2 mm and constitute a major site of pathology and inflammation in asthma disease. It is estimated that small airways dysfunction may occur before the emergence of noticeable symptoms, spirometric abnormalities and imaging findings, thus characterizing them as "the quiet or silent zone" of the lungs. Despite their importance, measuring and quantifying small airways dysfunction presents a considerable challenge due to their inaccessibility in usual functional measurements, primarily due to their size and peripheral localization. Several pulmonary function tests have been proposed for the assessment of the small airways, including impulse oscillometry, nitrogen washout, body plethysmography, as well as imaging methods. Nevertheless, none of these methods has been established as the definitive "gold standard," thus, a combination of them should be used for an effective assessment of the small airways. Widely used asthma treatments seem to also affect several parameters of the small airways. Emerging biologic treatments show promising results in reducing small airways inflammation and remodelling, providing evidence for potential alterations in the disease's progression and outcomes. These novel therapies have implications not only in the clinical aspects of asthma but also in its inflammatory and functional aspects.

Patient response to the management during the acute presentation of cough variant Asthma: Retrospective cohort study

The clinical improvement after assessing patients with cough variant asthma in outpatient clinics, and therapy success varied depending on the subjective improvement. Cough could be controlled within appropriate time and subsequent management can consist of inhaled corticosteroids. In this study we used the cough improvement, the only available clinical response, as a predictable factor to determine the effect of different modalities of treatment among patients with cough variant asthma. Retrospective observational analysis was performed in Saudi Arabia's King Saud University Medical City, on the presentation, diagnosis, course of therapy, and responsiveness to oral and inhaled steroids in patients with cough variant asthma. All patients who visited the clinic on multiple occasions with persistent, acute coughing without being pre-screened between September 2021 and September 2022 included based on medical records. Cough resembles cough variant asthma is the term used to describe a cough without a diagnosed etiology. To identify patients eligible for CVA treatment, iindividuals having GERD-associated cough, allergic rhinitis, bronchial asthma, smokers and atopic cough was excluded. For the examination of these findings, IBM SPSS version 28 (Armonk, NY, USA) was employed. As a result of using budesonide-formoterol inhaler, most patients (86.3 %) showed improvement in their cough symptoms (with 95 %CI: 78.3 to 94.9). There was a significant yet weak positive correlation between the frequency of cough symptoms before and after using budesonide-formoterol (r = 0.318, P value < 0.001). The understanding of treatment response and patient selection for budesonide-formoterol inhaler therapy, providing clinicians with valuable information to optimize patient care.

Impulse oscillometry defined small airway dysfunction in asthmatic patients with normal spirometry: Prevalence, clinical associations, and impact on asthma control

BACKGROUND

The small-airway dysfunction (SAD), detected with impulse oscillometry (IOS) methods, has been recently better characterized in patients with asthma. However, little is known about SAD in asthmatic patients with normal spirometry (NS).

OBJECTIVE

In this study, we aimed to investigate, in an unselected sample of 321 patients with physician-diagnosed asthma and NS, prevalence, clinical characterization, and impact on asthma control of IOS-defined SAD. As a secondary objective of the study, we focused on comparing the difference between IOS- and spirometry-defined SAD.

METHODS

Consecutive patients with a previous diagnosis of asthma but normal spirometry at the moment of the enrollment were stratified by the presence of IOS-defined SAD (difference in resistance at 5 Hz and at 20 Hz [R5-R20] greater than 0.07 kPa x s x L-1). We have also assessed the presence of SAD defined by spirometry, according to FEF 25-75 < 65% of the predicted. Clinical and laboratory features were collected, and univariable and multivariable analyses were used to analyze cross-sectional associations between clinical variables and outcomes (SAD).

RESULTS

IOS-defined SAD was present in 54.1% of the cohort. In contrast, spirometry-defined SAD was present in only 10% of patients. Subjects with IOS-defined SAD showed less well-controlled asthma and a higher mean inhaled corticosteroid dosage use compared with subjects without SAD (both P < .001). Overweight (odds ratio [OR], 1.14; 95% CI, 1.05-1.23), exacerbation history (OR, 3.06; 95% CI, 1.34-6.97), asthma-related night awakenings (OR, 6.88; 95% CI, 2.13-22.23), exercise-induced asthma symptoms (OR, 33.5; 95% CI, 9.51-117.8), and controlled asthma (OR, 0.22; 95% CI, 0.06-0.84) were independently associated with SAD.

CONCLUSIONS

Asthmatic patients with IOS-defined SAD showed less well-controlled asthma, more severe exacerbations and higher mean inhaled corticosteroid dosage. We confirmed exercise-induced asthma, asthma-related night awakenings, exacerbation history, and overweight as independently associated with SAD, while showing well-controlled asthma as inversely associated. SAD may be overlooked by standard spirometry.

Metered dose inhalers in the transition to low GWP propellants: what we know and what is missing to make it happen

INTRODUCTION

The urgency to replace the propellants currently in use with the new sustainable ones has given rise to the need for investigation and reformulation of pMDIs.

AREAS COVERED

The reformulation requires in-depth knowledge of the physico-chemical characteristics of the new propellants, which impact the atomization capacity and the plume geometry. Among the investigated propellants, HFA 152a, due to its lower vapor pressure and higher surface tension compared to HFA 134a, deliver larger particles and has a higher solvent capacity toward lipophilic drugs. On the other hand, HFO 1234ze has properties more similar to HFA 134a, but showed lower reproducibility of the generated spray, indicating a possible high susceptibility to variation in the consistency of the dose delivered. In addition, the device components currently in use are compatible with the new propellants. This allowed promising preliminary results in the re-formulation of pMDIs by academia and pharma companies. However, there is little information about the clinical studies required to allow the marketing of these new products.

EXPERT OPINION

Overall, studies conducted so far show that the transition is technically possible, and the main obstacle will be represented by the investment required to put the product on the market.

FIDEPOC: Consensus on Inspiratory Flow and Lung Deposition as Key Decision Factors in COPD Inhaled Therapy

Purpose

The pharmacological treatment of chronic obstructive pulmonary disease (COPD) is largely based on inhaled bronchodilators. Inspiratory flow and lung deposition are key parameters to be considered in inhaled therapy; however, the relationship between these two parameters, the patient specificities, and the suitability of the inhaler type for COPD management has not been fully addressed. The present study follows a Delphi Panel methodology to find expert consensus on the role of inspiratory flow and lung deposition as key decision factors in COPD inhaled therapy.

Methods

A two-round Delphi Panel, consisting of 38 statements (items) and completed by 57 Spanish pulmonologists, was carried out to measure the experts' consensus degree with each item.

Results

A high degree of consensus was reached on most of the items consulted, among these inspiratory flow or inspiratory capacity should be periodically considered when choosing an inhalation device and to ensure the suitability of the inhaler used; the outflow velocity and particle size of the different devices should be considered to ensure adequate lung deposition; an active device (pressurized metered-dose inhalers (pMDI) or soft mist inhalers (SMI)) should be used in patients with low inspiratory flow to achieve adequate lung deposition; and, the use of dry powder inhalers (DPI) should be re-evaluated in patients with severe obstruction and severe exacerbations.

Conclusion

This study shows the relevance of inspiratory flow and the degree of particle deposition in the lung in the choice of an inhalation device for COPD management, as well as the convenience of an SMI type device in cases of low inspiratory flow. Moreover, it highlights the scarcity of information on the specific features of inhalation devices in COPD guidelines.

Systematic Evaluation of the Effect of Formulation Variables on In Vitro Performance of Mometasone Furoate Suspension-Metered Dose Inhalers

The therapeutic benefits of metered dose inhalers (MDIs) in pulmonary disorders are mainly driven by aerosol performance, which depends on formulation variables (drug and excipients), device design, and patient interactions. The present study provides a comprehensive investigation to better understand the effect of formulation variables on mometasone furoate (MF) suspension-based MDI product performance. The effects of MF particle size (volume median diameter; X50) and excipient concentration (ethanol and oleic acid, cosolvent, and surfactant, respectively) on selected critical quality attributes (delivered dose (DD), fine particle dose of particles lesser than 5 µm (FPD < 5), ex-throat dose and median dissolution time (MDT)) were studied. Eight MF-MDI formulations (one per batch) were manufactured based on a reduced factorial design of experiment (DOE) approach, which included relevant formulation levels with varying X50 (1.1 and 2 μm), concentration of ethanol (0.45, 0.9, 1.8, and 3.6%w/w), and oleic acid (0.001 and 0.025%w/w). The in vitro evaluation of these MF-MDI formulations indicated the importance of drug particle's X50, oleic acid, and ethanol canister concentration as critical formulation variables governing the performance of MF suspension-based MDI products. The effect of these formulation variables on DD, FPD < 5, ex-throat dose, and MDT was subsequently utilized to develop empirical relationships linking formulation factors with effects on in vitro performance measures. The developed strategy could be useful for predicting MF-MDI product performance during MDI product development and manufacturing. The systematic DOE approach utilized in this study may provide insights into the understanding of the formulation variables governing the MF-MDI product performance.

Effects of Medication Use on Small Airway Function and Airway Inflammation in Patients with Clinically Controlled Asthma

OBJECTIVE

To observe effects of medication use on small airway function, airway inflammation and acute exacerbations in patients with clinically controlled asthma.

METHODS

Forced expiratory flow over the middle half of the forced expiratory curve (FEF_25%-75%), percentage of eosinophil, concentrations of eosinophil cationic protein (ECP) and interleukin (IL)-5 in induced sputum were assessed in patients with clinically controlled asthma who were given oral anti-inflammatory agents alone or in combination with inhaled therapy and inhaled therapy alone. Subsequently, acute exacerbations were compared between two groups during the 24-week follow-up period.

RESULTS

FEF_25%-75% in 43 patients with clinically controlled asthma given oral anti-inflammatory agents alone or in combination with inhaled therapy was significantly higher than that in 49 patients given inhaled therapy alone. Meanwhile, the percentage of eosinophils and levels of IL-5 and ECP in patients with clinically controlled asthma given oral anti-inflammatory agents alone or in combination with inhaled therapy were significantly lower than those in patients given inhaled therapy alone. Additionally, the patients with clinically controlled asthma given inhaled therapy were likely to have more acute exacerbation than the patients given oral anti-inflammatory agents alone or in combination with inhaled therapy during the 24-week follow-up period.

CONCLUSION

Systemic anti-inflammatory agents may have a greater effect on parameters reflecting small airway patency and reducing acute exacerbations, presumably secondary to reduction in airway inflammation.

Pulmonary Drug Delivery of Antimicrobials and Anticancer Drugs Using Solid Dispersions

It is well established that currently available inhaled drug formulations are associated with extremely low lung deposition. Currently available technologies alleviate this low deposition problem via mixing the drug with inert larger particles, such as lactose monohydrate. Those inert particles are retained in the inhalation device or impacted in the throat and swallowed, allowing the smaller drug particles to continue their journey towards the lungs. While this seems like a practical approach, in some formulations, the ratio between the carrier to drug particles can be as much as 30 to 1. This limitation becomes more critical when treating lung conditions that inherently require large doses of the drug, such as antibiotics and antivirals that treat lung infections and anticancer drugs. The focus of this review article is to review the recent advancements in carrier free technologies that are based on coamorphous solid dispersions and cocrystals that can improve flow properties, and help with delivering larger doses of the drug to the lungs.

Small airway dysfunction and poor asthma control: a dangerous liaison

Asthma is a common chronic condition, affecting approximately 339 million people worldwide. The main goal of the current asthma treatment guidelines is to achieve clinical control, encompassing both the patient symptoms and limitations and the future risk of adverse asthma outcomes. Despite randomized controlled trials showing that asthma control is an achievable target, a substantial proportion of asthmatics remain poorly controlled in real life. The involvement of peripheral small airways has recently gained greater recognition in asthma, and many studies suggest that the persistent inflammation at these sites leads to small airway dysfunction (SAD), strongly contributing to a worse asthma control. Overall, the impulse oscillometry (IOS), introduced in the recent years, seems to be able to sensitively assess small airways, while conventional spirometry does not. Therefore, IOS may be of great help in characterizing SAD and guiding therapy choice. The aim of this article is to review the literature on SAD and its influence on asthma control, emphasizing the most recent evidence.

Lung Deposition and Inspiratory Flow Rate in Patients with Chronic Obstructive Pulmonary Disease Using Different Inhalation Devices: A Systematic Literature Review and Expert Opinion

BACKGROUND

Our aim was to describe: 1) lung deposition and inspiratory flow rate; 2) main characteristics of inhaler devices in chronic obstructive pulmonary disease (COPD).

METHODS

A systematic literature review (SLR) was conducted to analyze the features and results of inhaler devices in COPD patients. These devices included pressurized metered-dose inhalers (pMDIs), dry powder inhalers (DPIs), and a soft mist inhaler (SMI). Inclusion and exclusion criteria were established, as well as search strategies (Medline, Embase, and the Cochrane Library up to April 2019). In vitro and in vivo studies were included. Two reviewers selected articles, collected and analyzed data independently. Narrative searches complemented the SLR. We discussed the results of the reviews in a nominal group meeting and agreed on various general principles and recommendations.

RESULTS

The SLR included 71 articles, some were of low-moderate quality, and there was great variability regarding populations and outcomes. Lung deposition rates varied across devices: 8%-53% for pMDIs, 7%-69% for DPIs, and 39%-67% for the SMI. The aerosol exit velocity was high with pMDIs (more than 3 m/s), while it is much slower (0.84-0.72 m/s) with the SMI. In general, pMDIs produce large-sized particles (1.22-8 μm), DPIs produce medium-sized particles (1.8-4.8 µm), and 60% of the particles reach an aerodynamic diameter <5 μm with the SMI. All inhalation devices reach central and peripheral lung regions, but the SMI distribution pattern might be better compared with pMDIs. DPIs' intrinsic resistance is higher than that of pMDIs and SMI, which are relatively similar and low. Depending on the DPI, the minimum flow inspiratory rate required was 30 L/min. pMDIs and SMI did not require a high inspiratory flow rate.

CONCLUSION

Lung deposition and inspiratory flow rate are key factors when selecting an inhalation device in COPD patients.

Small airways in asthma: from bench-to-bedside

INTRODUCTION

Historically, asthma was considered a disease predominantly of the large airways, but gradually small airways have been recognized as the major site of airflow obstruction. Small airway dysfunction (SAD) significantly contributes to the pathophysiology of asthma and it is present across all asthma severities. Promising pre-clinical findings documented enhanced beneficial effects of combination therapies on small airways compared to monocomponents, thus it was questioned whether this could translate into further clinical implications from bench-to-bedside. The aim of this review was to systematically assess the state of the art of small airway involvement in asthma, especially in response to different pharmacological treatments acting on the respiratory system.

EVIDENCE ACQUISITION

A comprehensive literature search was performed in MEDLINE for randomized controlled trials (RCTs) characterizing the impact on small airways of different pharmacological treatments acting on the respiratory system. The results were extracted and reported via qualitative synthesis.

EVIDENCE SYNTHESIS

Overall, 63 studies were identified from the literature search, whereas 23 RCTs met the inclusion criteria. Evidence confirms that both drug particle size and the type of inhalation devices represent two of the most important variables for an effective peripheral lung distribution.

CONCLUSIONS

Despite the numerous methodological tools to detect SAD, there is still no gold standard diagnostic method to assess small airways, especially in severe asthma. Further research should be directed to improve primary and secondary prevention strategies by supporting the combined approach of different non-invasive techniques for an early detection of peripheral abnormalities and optimization of asthma therapy.

A retrospective analysis of usefulness of impulse oscillometry system in the treatment of asthma

BACKGROUND

Bronchial asthma (BA) has different phenotypes, and it requires a clinically effective subtype classification system. The impulse oscillometry system (IOS) is an emerging technique device used in respiratory functional tests. However, its efficacy has not been validated. Therefore, this study aimed to assess the relationship between BA and the IOS parameters, and the difference in the therapeutic effects of inhaled corticosteroids (ICSs) among the subtype classifications was evaluated using the IOS.

METHODS

Of the 245 patients with bronchial asthma who were screened, 108 were enrolled in this study. These patients were divided based on three subtypes according to the IOS result as follows: central predominant type (n = 34), peripheral predominant type (n = 58), and resistless type (n = 16). Then, the following ICSs were randomly prescribed in daily medical care: coarse-particle ICS (fluticasone propionate [FP]), fine-particle ICS (mometasone furoate [MF]), and moderate-particle ICS (budesonide [BUD]). The treatment effects were assessed using the Asthma Health Questionnaire (AHQ) and the Asthma Control Test (ACT) and were compared among the three subtypes.

RESULTS

In the central predominant type, the AHQ score of the MF group was significantly higher than that of the FP group (15.4 vs. 3.6, p < 0.01) and the BUD group (15.4 vs. 8.8, p < 0.05); the ACT score of the FP group was significantly higher than that of the MF and BUD groups (24.3 vs. 21.7, 22.3, respectively, p < 0.05) at 4 weeks after treatment. In the peripheral predominant type, the AHQ score of the FP group was significantly higher than that of the MF group (14.1 vs. 3.4, p < 0.05); the ACT score of the FP group was lower than that of the MF and BUD groups (22.8 vs. 24.6, 24.4, respectively, p < 0.01) at 4 weeks after treatment.

CONCLUSIONS

An association was observed between IOS subtype classification and ICS particle size in terms of therapeutic efficacy in BA. This result indicates that the IOS could be an effective tool in the selection of ICS and the evaluation of the BA phenotype.

Cascade Impactor Performance of Commercial pMDI Formulations Using Modified Induction Ports

The induction port (IP) for aerosol analysis with the Next Generation Pharmaceutical Impactor as monographed in the United States and European pharmacopoeia (USPIP) lacks physiological relevance, which, amongst other reasons, has been identified as critical for the predictability of in vitro aerosol data to lung deposition observed in vivo. In this publication, we report the impact of replacing the USPIP with two modified induction ports, which were designed based around geometries derived from a computer tomographic scan of a human trachea and the distal section of the USPIP. Test formulations were selected on the basis of availability of in vivo lung deposition data so that results obtained in vitro could be evaluated for their predictability. All formulations assessed showed increased deposition in the modified induction ports, and different mechanisms of particle deposition have been identified. In vitro predictions of the lung deposition were found to correlate well with the in vivo observations reported using the modified induction ports. Furthermore, the quality of the correlation was found superior to the one achieved with the USPIP with an average deviation of the predicted from observed values (n = 10) of 6 ± 4, 12 ± 6, and 16 ± 6% for the modified induction ports (mIP and mIPext) and the USPIP, respectively, when using a fine particle fraction (FPF) cutoff value of 5 μm. Using a FPF cutoff value of 3 μm yielded a more accurate in vitro-in vivo correlation with an average deviation of the predicted from observed values of 5 ± 4, 7 ± 5, and 8 ± 4% for the mIP, mIPext, and USPIP, respectively. For both FPF size cutoff values, the mIP yielded the most accurate in vitro-in vivo correlation.

Controller Inhalers: Overview of Devices, Instructions for Use, Errors, and Interventions to Improve Technique

Inadequate inhaler technique in persistent asthma is frequently reported. However, there is little consensus on inhaler checklists, and critical elements of technique are not uniformly described. In addition, inhaler error rates and risk factors for poor technique are variable across studies. This Clinical Commentary Review summarizes the literature on inhaler design, use, and interventions to improve technique. Our aim is to help clinicians identify patients with poor inhaler technique, recognize the most important errors, and correct technique using evidence-based interventions.

Challenges and choices in the pharmacological treatment of non-severe pediatric asthma: A commentary for the practicing physician

In recent years, asthma research has focused intensely on the severe part of the disease spectrum, leading to new treatments, mostly therapeutic monoclonal antibodies. However, severe asthma accounts for not more than 2% of asthma in the pediatric population. Therefore, non-severe asthma remains a major health problem in children, not only for patients and parents but also for healthcare professionals such as general practitioners, pediatricians and allergists who take care of these patients. It is thus essential to identify and put in context novel concepts, applicable to the treatment of these patients. Recent evidence suggests benefits from using anti-inflammatory treatment even for the mildest cases, for whom until now only symptomatic bronchodilation was recommended. Likewise, “reliever” medication may be better combined with an inhaled corticosteroid (ICS). Among “new” treatments (for children), ICS formulation in ultrafine particles has showed promise and tiotropium is gaining access to the pediatric population. Maintenance and reliever therapy (MART) is an option for moderate disease. Most importantly, personalized response to medications appears to be considerable, therefore, it may need to be taken into account. Overall, these new options provide opportunities for multiple new management strategies. The deployment of such strategies in different populations remains to be evaluated.

Recent Advances in Inflammation and Treatment of Small Airways in Asthma

Small airways were historically considered to be almost irrelevant in the development and control of pulmonary chronic diseases but, as a matter of fact, in the past few years we have learned that they are not so "silent". Asthma is still a worldwide health issue due to the great share of patients being far from optimal management. Several studies have shown that the deeper lung inflammation plays a critical role in asthma pathogenesis, mostly in these not well-controlled subjects. Therefore, assessing the degree of small airways inflammation and impairment appears to be a pivotal step in the asthmatic patient's management. It is now possible to evaluate them through direct and indirect measurements, even if some obstacles still affect their clinical application. The success of any treatment obviously depends on several factors but reaching the deeper lung has become a priority and, for inhaled drugs, this is strictly connected to the molecule's size. The aim of the present review is to summarize the recent evidence concerning the small airway involvement in asthma, its physiopathological characteristics and how it can be evaluated in order to undertake a personalized pharmacological treatment and achieve a better disease control.

Comparison of therapeutic effects of inhaled corticosteroids on three subtypes of cough variant asthma as classified by the impulse oscillometry system

BACKGROUND

Cough variant asthma (CVA) is one of the most common causes of chronic persistent cough, and early treatment with inhaled corticosteroids (ICSs) is recommended to attenuate the inflammation and remodeling. The impulse oscillometry system (IOS) is a novel device for respiratory functional assessment that has not yet been assessed in terms of CVA. Therefore, we investigated the relationship between CVA and IOS, and the difference in therapeutic effects of ICSs among the subtype classifications by IOS.

METHODS

The following ICSs were randomly prescribed in daily medical care: coarse-particle ICS (fluticasone propionate [FP]), fine-particle ICS (mometasone furoate [MF]), and moderate-particle ICS (budesonide [BUD]). Treatment effects were assessed by the Leicester cough questionnaire (LCQ) and were compared among three separated subtypes based on IOS measurements: central, peripheral, and resistless.

RESULTS

Regarding LCQ scores, in the central type, the LCQ of the MF group was significantly lower than FP and BUD. In the peripheral type, the LCQ of the FP group was significantly lower than MF and BUD. In the resistless type, the LCQ of the MF group was significantly lower than BUD. Also, IOS factors were improved by 4 weeks of therapy with ICS. Thus, there was strong relationship between subtypes and particle size in terms of effectiveness.

CONCLUSIONS

There is a strong relationship between IOS subtype classification and ICS particle size in terms of therapeutic efficiency in CVA. It appears important to determine the ICS particle size, based on the IOS subtype classification, before treatment.

Repurposing drugs as inhaled therapies in asthma

For the first 40 years of the 20th century treatment for asthma occurred in response to an asthma attack. The treatments were given by injection or orally and included the adrenergic agonists adrenalin/epinephrine and ephedrine and a phosphodiesterase inhibitor theophylline. Epinephrine became available as an aerosol in 1930. After 1945, isoprenaline, a non-selective beta agonist, became available for oral use but it was most widely used by inhalation. Isoprenaline was short-acting with unwanted cardiac effects. More selective beta agonists, with a longer duration of action and fewer side-effects became available, including orciprenaline in 1967, salbutamol in 1969 and terbutaline in 1970. The inhaled steroid beclomethasone was available by 1972 and budesonide by 1982. Spirometry alone and in response to exercise was used to assess efficacy and duration of action of these drugs for the acute benefits of beta₂ agonists and the chronic benefits of corticosteroids. Early studies comparing oral and aerosol beta₂ agonists found equivalence in bronchodilator effect but the aerosol treatment was superior in preventing exercise-induced bronchoconstriction. Inhaled drugs are now widely used including the long-acting beta₂ agonists, salmeterol and formoterol, and the corticosteroids, fluticasone, ciclesonide, mometasone and triamcinolone, that act locally and have low systemic bio-availability. Repurposing drugs as inhaled therapies permitted direct delivery of low doses of drug to the site of action reducing the incidence of unwanted side-effects and permitting the prophylactic treatment of asthma.

Management of severe COPD exacerbations: focus on beclomethasone dipropionate/formoterol/glycopyrronium bromide

The major determinant of the decline in lung function, quality of life, and the increased mortality risk in patients with COPD is represented by severe acute exacerbations of the disease, that is, those requiring patients’ hospitalization, constituting a substantial social and health care burden in terms of morbidity and medical resource utilization. Different long-term therapeutic strategies have been proposed so far in order to prevent and/or reduce the clinical and social impact of these events, the majority of which were extrapolated from trials initially focused on the effect of long-acting muscarinic antagonist and subsequently on the efficacy of long-acting β2-agonists in combination or not with inhaled corticosteroids. The option to employ all three classes of molecules combined, despite the limited amount of evidence in our possession, represents a choice currently proposed by international guidelines; however, current recommendations are often based mainly on observational studies or on the results of secondary outcomes in randomized controlled trials. The present narrative review evaluates the available trials that investigated the efficacy of inhaled therapy to prevent COPD exacerbations and especially severe ones, with a particular focus on beclomethasone dipropionate/formoterol/glycopyrronium bromide fixed dose combination, which is the first treatment that comprises all the three drug classes, specifically tested for the prevention of moderate and severe COPD exacerbations.

Lung Deposition of the Dry Powder Fixed Combination Beclometasone Dipropionate Plus Formoterol Fumarate Using NEXThaler® Device in Healthy Subjects, Asthmatic Patients, and COPD Patients

Background: This study evaluated the lung deposition and the distribution pattern in the airways of a fixed combination of beclometasone dipropionate (BDP) and formoterol fumarate (FF) (100/6 μg) delivered as an extrafine dry powder formulation (mass median aerodynamic diameter, MMAD (μm) BDP = 1.5; FF = 1.4) through the NEXThaler^® device in healthy subjects, asthmatics, and patients with COPD.

Methods: Healthy subjects (n = 10), asthmatic patients (n = 9; 30%≤FEV₁ < 80%), and COPD patients (n = 9; FEV₁/FVC ≤70%, 30%≤FEV₁ < 50%) completed this open-label, single administration (inhalation of four actuations) parallel group study. After inhalation of ^99mTc-radiolabeled BDP/FF combination (radiolabeled BDP + unlabeled FF), the drug deposition was assessed using a gamma-scintigraphy technique. Patients' lung function was assessed.

Results: No significant difference in drug deposition was observed between the three study groups. Mean lung deposition, extrathoracic deposition, and amount exhaled ranged, respectively, between 54.9% and 56.2%, between 41.8% and 43.2%, and between 1.6% and 3.3% of BDP emitted dose (71.7 ± 2.5 μg) for the three study groups. The central to peripheral ratio (reflecting the lung distribution pattern) ranged between 1.23 and 2.02 for the three study groups, indicating a distribution of the drug throughout the airways, including periphery. The study treatment produced a forced expiratory volume in one second (FEV₁) increase over time, reaching a maximum improvement generally within 1–4 hours.

Conclusions: The fixed extrafine dry powder combination BDP/FF (100/6 μg) administered through the DPI NEXThaler^® achieved similar intrapulmonary deposition in healthy subjects, in asthmatic patients, and COPD patients (approximately 55% of emitted dose) irrespective of the underlying lung disease with a negligible amount of exhaled particles. The study showed high reliability of the device, reproducible dosing, and distribution throughout the lungs. The results supported the concept of efficient delivery of the combination to the target pulmonary regions, thanks to the extrafine formulation. FEV₁ profile confirmed a relevant pharmacodynamic effect of the product.

Effects of Formulation Variables on Lung Dosimetry of Albuterol Sulfate Suspension and Beclomethasone Dipropionate Solution Metered Dose Inhalers

The performance of pressurized metered dose inhalers (MDIs) is affected by formulation and device variables that impact delivered dose, aerodynamic particle size distribution, and consequently lung deposition and therapeutic effect. Specific formulation variables of relevance to two commercially available products-Proventil® HFA [albuterol sulfate (AS) suspension] and Qvar® [beclomethasone dipropionate (BDP) solution]-were evaluated to determine their influence on key performance attributes measured experimentally with in vitro cascade impaction studies. These commercial MDIs, utilized as model systems, provided mid-points for a design of experiments (DoE) plan to manufacture multiple suspension and solution MDI formulations. The experimental results were utilized as input variables in a computational dosimetry model to predict the effects of MDI formulation variables on lung deposition. For the BDP solution DoE MDIs, increased concentrations of surfactant oleic acid (0-2% w/w) increased lung deposition from 24 to 46%, whereas changes in concentration of the cosolvent ethanol (7-9% w/w) had no effect on lung deposition. For the AS suspension DoE MDIs, changes in oleic acid concentration (0.005-0.25% w/w) did not have significant effects on lung deposition, whereas lung deposition decreased from 48 to 26% as ethanol concentration increased from 2 to 20% w/w, and changes in micronized drug volumetric median particle size distribution (X₅₀, 1.4-2.5 μm) increased deposition in the tracheobronchial airways from 5 to 11%. A direct correlation was observed between fine particle fraction and predicted lung deposition. These results demonstrate the value of using dosimetry models to further explore relationships between performance variables and lung deposition.

Pulmonary deposition of fluticasone propionate/formoterol in healthy volunteers, asthmatics and COPD patients with a novel breath-triggered inhaler

INTRODUCTION

A combination of fluticasone propionate/formoterol fumarate (FP/FORM) has been incorporated within a novel, breath-triggered device, named K-haler^®. This low resistance device requires a gentle inspiratory effort to actuate it, triggering at an inspiratory flow rate of approximately 30 L/min; thus avoiding the need for coordination of inhalation with manual canister depression. The aim of the study was to evaluate total and regional pulmonary deposition of FP/FORM when administered via the K-haler device.

MATERIALS AND METHODS

Twelve healthy subjects, 12 asthmatics, and 12 COPD patients each received a single dose of 2 puffs ^99mtechnetium-labelled FP/FORM 125/5 μg. A gamma camera was used to obtain anterior and posterior two-dimensional images of drug deposition. Prior transmission scans (using a^99mtechnetium flood source) allowed the definition of regions of interest and calculation of attenuation correction factors. Image analysis was performed per standardised methods.

RESULTS

Of 36 subjects, 35 provided evaluable post-dose scintigraphic data. Mean subject ages were 35.7 (healthy), 44.5 (asthma) and 61.7 years (COPD); mean FEV₁% predicted values were 109.8%, 77.4% and 43.2%, respectively. Mean pulmonary deposition was 26.6% (healthy), 44.7% (asthma), 39.0% (COPD) of the delivered dose. The respective mean penetration indices (peripheral:central ratio normalised to a transmission lung scan) were 0.44, 0.31 and 0.30.

CONCLUSION

FP/FORM administration via the K-haler device resulted in high lung deposition in patients with obstructive lung disease but somewhat lesser deposition in healthy subjects. Regional deposition data demonstrated drug deposition in both the central and peripheral regions in all subject populations.

EUDRACT NUMBER

2015-000744-42.

Small Airway Absorption and Microdosimetry of Inhaled Corticosteroid Particles after Deposition

PURPOSE

To predict the cellular-level epithelial absorbed dose from deposited inhaled corticosteroid (ICS) particles in a model of an expanding and contracting small airway segment for different particle forms.

METHODS

A computational fluid dynamics (CFD)-based model of drug dissolution, absorption and clearance occurring in the surface liquid of a representative small airway generation (G13) was developed and used to evaluate epithelial dose for the same deposited drug mass of conventional microparticles, nanoaggregates and a true nanoaerosol. The ICS medications considered were budesonide (BD) and fluticasone propionate (FP). Within G13, total epithelial absorption efficiency (AE) and dose uniformity (microdosimetry) were evaluated.

RESULTS

Conventional microparticles resulted in very poor AE of FP (0.37%) and highly nonuniform epithelial absorption, such that <5% of cells received drug. Nanoaggregates improved AE of FP by a factor of 57-fold and improved dose delivery to reach approximately 40% of epithelial cells. True nanoaerosol resulted in near 100% AE for both drugs and more uniform drug delivery to all cells.

CONCLUSIONS

Current ICS therapies are absorbed by respiratory epithelial cells in a highly nonuniform manner that may partially explain poor clinical performance in the small airways. Both nanoaggregates and nanoaerosols can significantly improve ICS absorption efficiency and uniformity.

Extrafine Versus Fine Inhaled Corticosteroids in Relation to Asthma Control: A Systematic Review and Meta-Analysis of Observational Real-Life Studies

BACKGROUND

The particle size of inhaled corticosteroids (ICSs) may affect airway drug deposition and effectiveness.

OBJECTIVE

To compare the effectiveness of extrafine ICSs (mass median aerodynamic diameter, <2 μm) versus fine-particle ICSs administered as ICS monotherapy or ICS-long-acting β-agonist combination therapy by conducting a meta-analysis of observational real-life asthma studies to estimate the treatment effect of extrafine ICSs.

METHODS

MEDLINE and EMBASE databases were reviewed for asthma observational comparative effectiveness studies from January 2004 to June 2016. Studies were included if they reported odds and relative risk ratios and met all inclusion criteria (Respiratory Effectiveness Group/European Academy of Allergy and Clinical Immunology quality standards, comparison of extrafine ICSs with same or different ICS molecule, ≥12-month follow-up). End-point data (asthma control, exacerbations, prescribed ICS dose) were pooled. Random-effects meta-analysis modeling was used. The study protocol is published in the PROSPERO register CRD42016039137.

RESULTS

Seven studies with 33,453 subjects aged 5 to 80 years met eligibility criteria for inclusion. Six studies used extrafine beclometasone propionate and 1 study used both extrafine beclometasone propionate and extrafine ciclesonide as comparators with fine-particle ICSs. The overall odds of achieving asthma control were significantly higher for extrafine ICSs compared with fine-particle ICSs (odds ratio, 1.34; 95% CI, 1.22-1.46). Overall exacerbation rate ratios (0.84; 95% CI, 0.73-0.97) and ICS dose (weighted mean difference, -170 μg; 95% CI, -222 to -118 μg) were significantly lower for extrafine ICSs compared with fine-particle ICSs.

CONCLUSIONS

This meta-analysis demonstrates that extrafine ICSs have significantly higher odds of achieving asthma control with lower exacerbation rates at significantly lower prescribed doses than fine-particle ICSs.

Drug Delivery Devices for Inhaled Medicines

Historically, the inhaled route has been used for the delivery of locally-acting drugs for the treatment of respiratory conditions, such as asthma, COPD, and airway infections. Targeted delivery of substances to the lungs has some key advantages over systemic administration, including a more rapid onset of action, an increased therapeutic effect, and, depending on the agent inhaled, reduced systemic side effects since the required local concentration in the lungs can be obtained with a lower dose. Fortunately, when designed properly, inhaled drug delivery devices can be very effective and safe for getting active agents directly to their site of action.

Tracheobronchopathy From Inhaled Corticosteroids

Inhaled corticosteroids (ICSs) have become the mainstay of asthma control. They are also recommended as an add-on therapy to long-acting beta agonists and anticholinergics in moderate to severe COPD with recurrent exacerbations. Ultimately this clinical practice has led to the widespread use of ICSs, which are supported by a more favorable side effect profile than that of systemic steroids.

Asthma pressurised metered dose inhaler performance: propellant effect studies in delivery systems

BACKGROUND

Current pressurised metered dose asthma inhaler (pMDI) propellants are not inert pharmacologically as were previous chlorofluorocarbons, have smooth muscle relaxant' partial pressure effects in the lungs and inhaled hydrofluoroalkane 134a (norflurane) has anaesthetic effects. Volumes of propellant gas per actuation have never been measured.

METHODS

In-vitro studies measured gas volumes produced by pMDIs on air oxygen (O2) levels in valved holding chambers (VHC) and the falls in O2% following actuation into lung ventilator delivery devices.

RESULTS

Volumes of propellant gas hydrofluoroalkane (HFA) 134a and 227ea and redundant chlorofluorocarbons (CFC) varied from 7 ml per actuation from a small salbutamol HFA inhaler to 16 ml from the larger. Similar-sized CFC pMDI volumes were 15.6 and 20.4 ml. Each HFA salbutamol inhaler has 220 full volume discharges; total volume of gas from a small 134a pMDI was 1640 ml, and large 3885 ml. Sensing the presence of liquid propellant by shaking was felt at the 220th discharge in both large and small inhalers. Because of a partial pressure effect, VHC O2% in air was reduced to 11% in the smallest 127 ml volume VHC following 10 actuations of a large 134a salbutamol inhaler. The four ventilator delivery devices studied lowered 100% oxygen levels to a range of 93 to 81% after five actuations, depending on the device and type of pMDI used.

CONCLUSION

Pressurised inhaler propellants require further study to assess smooth muscle relaxing properties.

Asthma-COPD overlap syndrome-Coexistence of chronic obstructive pulmonary disease and asthma in elderly patients and parameters for their differentiation

Japan is an aging society, and the number of elderly patients with asthma and chronic obstructive pulmonary disease (COPD) is consequently increasing, with an estimated incidence of approximately 5 million. In 2014, asthma‐COPD overlap syndrome (ACOS) was defined by a joint project of Global Initiative for Asthma (GINA) committee and the Global Initiative for Chronic Obstructive Lung Disease (GOLD) committee. The main aims of this consensus‐based document are to assist clinicians, especially those in primary care or nonpulmonary specialties. In this article, we discussed parameters to differentiate asthma and COPD in elderly patients and showed prevalence, clinical features and treatment of ACOS on the basis of the guidelines of GINA and GOLD. Furthermore, we showed also referral for specialized investigations.

Inhaled hydrofluoalkane-beclomethasone dipropionate in bronchopulmonary dysplasia. A double-blind, randomized, controlled pilot study

OBJECTIVE

The efficacy of inhaled steroids in spontaneously breathing infants with established bronchopulmonary dysplasia (BPD) is debatable. The inhaled steroid hydrofluoalkane-beclomethasone dipropionate (QVAR) is unique in its small particle size that results in higher lung deposition. Our objective was to determine if inhaled QVAR could decrease respiratory rehospitalizations of infants with established BPD.

STUDY DESIGN

Double-blind, randomized placebo-controlled, multicenter pilot study. Preterm infants with moderate-to-severe BPD were randomized to inhaled QVAR 100 μg per dose or placebo twice daily via Aerochamber with face mask. Treatment was administered daily from recruitment at 36 weeks post menstrual age until 3 months post discharge. Analysis was carried out by intention to treat.

RESULTS

The QVAR (n=18) and placebo (n=20) groups were comparable in birth and recruitment characteristics. Length of stay (108.5±26.3 vs 108.7±36.0 days) and infants requiring oxygen at discharge (5/17 vs 6/19) or at study end (0/17 vs 2/19) were comparable. Respiratory rehospitalizations/infant (0.1±0.5 vs 0.4±0.6), rehospitalization days (0.5±1.5 vs 4.1±10.3), and post-discharge additive inhaled (0.3±0.9 vs 6.4±21.5 days), systemic (0.7±2.8 vs 1.0±1.4 days) and combined (inhaled/systemic) steroids (1.0±2.9 vs 7.8±25.8 days) tended to be lower in the QVAR compared with the placebo group. Blood pressure, height and weight gain, and urine cortisol/creatinine ratio at study end were comparable between groups.

CONCLUSIONS

Our study was unable to detect a significant effect of inhaled QVAR on the respiratory course of established BPD. The study was underpowered. Possible benefits of QVAR could be masked by a tendency toward higher use of additional steroids in the placebo group.

Real-Life Outcomes for Patients with Asthma Prescribed Spacers for Use with Either Extrafine- or Fine-Particle Inhaled Corticosteroids

BACKGROUND

Spacers are often used with pressurized metered-dose inhalers (pMDIs) to eliminate the need for coordinating inhalation with actuation.

OBJECTIVE

To investigate the real-life effectiveness of spacers prescribed for use with either extrafine- or fine-particle inhaled corticosteroids (ICSs).

METHODS

This historical matched cohort study examined anonymous medical record data over 2 years (1-year baseline, 1-year outcome) for patients with asthma aged 12 to 80 years initiating ICSs by pMDI with or without prescribed spacer. We compared outcomes for spacer versus no-spacer arms, matched for key baseline and asthma-related characteristics, within 2 ICS cohorts: (1) extrafine-particle ICS (beclomethasone) and (2) fine-particle ICS (fluticasone). Effectiveness end points were compared using conditional regression methods.

RESULTS

Matched spacer and no-spacer arms of the extrafine-particle ICS cohort each included 2090 patients (69% females; median age, 46-47 years) and the 2 arms of the fine-particle ICS cohort each included 444 patients (67% females; median age, 45 years). With extrafine-particle ICS, we observed no significant difference between spacer and no-spacer arms in severe exacerbation rate (primary end point): adjusted rate ratio, 1.01 (95% CI, 0.83-1.23). With fine-particle ICS, the severe exacerbation rate ratio with spacers was 0.77 (0.47-1.25). Oropharyngeal candidiasis incidence was low and similar in spacer and no-spacer arms for both ICS cohorts.

CONCLUSIONS

We found no evidence that prescribed spacer devices are associated with improved asthma outcomes for extrafine- or fine-particle ICS administered by pMDI. These findings challenge long-standing assumptions that spacers should improve pMDI effectiveness and indicate the need for pragmatic trials of spacers in clinical practice.

The History of Therapeutic Aerosols: A Chronological Review

In 1956, Riker Laboratories, Inc., (now 3 M Drug Delivery Systems) introduced the first pressurized metered dose inhaler (MDI). In many respects, the introduction of the MDI marked the beginning of the modern pharmaceutical aerosol industry. The MDI was the first truly portable and convenient inhaler that effectively delivered drug to the lung and quickly gained widespread acceptance. Since 1956, the pharmaceutical aerosol industry has experienced dramatic growth. The signing of the Montreal Protocol in 1987 led to a surge in innovation that resulted in the diversification of inhaler technologies with significantly enhanced delivery efficiency, including modern MDIs, dry powder inhalers, and nebulizer systems. The innovative inhalers and drugs discovered by the pharmaceutical aerosol industry, particularly since 1956, have improved the quality of life of literally hundreds of millions of people. Yet, the delivery of therapeutic aerosols has a surprisingly rich history dating back more than 3500 years to ancient Egypt. The delivery of atropine and related compounds has been a crucial inhalation therapy throughout this period and the delivery of associated structural analogs remains an important therapy today. Over the centuries, discoveries from many cultures have advanced the delivery of therapeutic aerosols. For thousands of years, therapeutic aerosols were prepared by the patient or a physician with direct oversight of the patient using custom-made delivery systems. However, starting with the Industrial Revolution, advancements in manufacturing resulted in the bulk production of therapeutic aerosol delivery systems produced by people completely disconnected from contact with the patient. This trend continued and accelerated in the 20th century with the mass commercialization of modern pharmaceutical inhaler products. In this article, we will provide a summary of therapeutic aerosol delivery from ancient times to the present along with a look to the future. We hope that you will find this chronological summary intriguing and informative.

Inhaled Corticosteroids and Voice Problems. What Is New?

BACKGROUND

Voice problems are the most common and most annoying local side effect of inhaled corticosteroids (ICS), affecting not only patients' treatment compliance but also their quality of life. The literature is very poor regarding prevalence, mechanism, prevention, and management of voice problems attributed to ICS use and especially for the new ICS, ciclesonide. Prevalence of dysphonia seems to be less common with the use of ciclesonide and beclomethasone dipropionate.

METHOD

We conducted a bibliography review based on recently published data, including data from the recently introduced ICS, ciclesonide, which are lacking in previous reviews.

RESULTS

Very little improvement, based on limited number of new papers published during previous years without any direct comparison between available ICS, has been made in our understanding of ICS local side effects.

CONCLUSION

Our understanding concerning basic information of ICS effects on voice still remains poor, and further investigation is needed to have a better understanding on epidemiology, predisposing factors, mechanisms, prevention, and treatment of voice problems attributed to ICS.

Dilemmas, Confusion, and Misconceptions Related to Small Airways Directed Therapy

During the past decade, there has been increasing evidence that the small airways (ie, airways < 2 mm in internal diameter) contribute substantially to the pathophysiologic and clinical expression of asthma and COPD. The increased interest in small airways is, at least in part, a result of innovation in small-particle aerosol formulations that better target the distal lung and also advanced physiologic methods of assessing small airway responses. Increasing the precision of drug deposition may improve targeting of specific diseases or receptor locations, decrease airway drug exposure and adverse effects, and thereby increase the efficiency and effectiveness of inhaled drug delivery. The availability of small-particle aerosols of corticosteroids, bronchodilators, or their combination enables a higher total lung deposition and better peripheral lung penetration and provides added clinical benefit, compared with large-particle aerosol treatment. However, a number of questions remain unanswered about the pragmatic approach relevant for clinicians to consider the role of small airways directed therapy in the day-to-day management of asthma and COPD. We thus have tried to clarify the dilemmas, confusion, and misconceptions related to small airways directed therapy. To this end, we have reviewed all studies on small-particle aerosol therapy systematically to address the dilemmas, confusion, and misconceptions related to small airways directed therapy.

Inhalation Aspects of Therapeutic Aerosols

The pulmonary route of drug delivery can provide an excellent alternative to other routes both for local lung disease as well as systemic delivery. The year 2006 marks the 50th year since the invention of metered dose inhalers, yet inhalation is a very much underutilized route of delivery, possibly because inhalation drug development is perceived as being too difficult and expensive. However with proper knowledge these purported difficulties can be overcome. The process begins with identifying the target tissue and then utilizing technologies such as particle size adjustments through formulation techniques and delivery devices to most efficiently deliver the desired dose. There are a variety of new and existing inhaled excipients available to accomplish this goal. The active molecule can also be modified to increase solubility, decrease immunogenicity, and protect it from unwanted metabolism using PEGylation. Sustained release of an inhaled drug is also possible using biocompatible matrices such as oligolactic acid.

Pharmacodynamic and pharmacokinetic considerations in choosing an inhaled corticosteroid

Inhaled corticosteroids are effective in controlling airway inflammation. Their anti-inflammatory effect is primarily topical, at the site of deposition in the airways. Consequently, traditional pharmacodynamic and pharmacokinetic concepts, which rely on measuring blood concentrations of drug, have limited applicability for evaluating the efficacy of topically acting inhaled corticosteroids. Important factors affecting efficacy of inhaled corticosteroids are: (i) intrinsic properties of the drugs, particularly their affinity for the corticosteroid receptor; and (ii) the newer pharmacodynamic concept of deposition characteristics of the drug formulation. Small particle formulations, especially those developed in the metered-dose inhaler with the new hydrofluoroalkane propellant, deposit to a much greater extent in the lung and may consequently have improved clinical efficacy. Lipid conjugation of inhaled corticosteroids within the lung may allow prolonged duration of effect, enabling once-daily administration. Pharmacodynamic and pharmacokinetic principles probably do not play a role in describing upper airway adverse effects occurring with inhaled corticosteroids. These are probably also determined by intrinsic properties of the drug and deposition characteristics. However, pharmacodynamic and pharmacokinetic principles seem to be important in addressing systemic safety concerns with inhaled corticosteroids. Those inhaled corticosteroids with a longer serum half-life, especially if they have higher affinity for the corticosteroid receptor, may be associated with greater systemic effects. A new pharmacokinetic concept suggests that increased protein binding within the systemic circulation and high systemic clearance of an inhaled corticosteroid may reduce the risk for systemic effects. These new pharmacodynamic and pharmacokinetic concepts provide a useful framework for identifying the characteristics of an inhaled corticosteroid with an improved benefit-to-risk profile. Increased lung deposition and reduced deposition in the upper airway should result in an inhaled corticosteroid with favorable clinical efficacy and a decreased risk for topical upper airway adverse effects. An inhaled corticosteroid with high plasma protein binding and rapid clearance might pose much less risk for systemic adverse effects than currently available drugs in this class.

Extra-fine particle inhaled corticosteroids, pharma-cokinetics and systemic activity in children with asthma

During recent years, extra-fine particle inhaled corticosteroids with a median aerodynamic diameter ≤2 μm have been introduced in the treatment of asthma. The aim of this paper was to review pharmacokinetics and systemic activity of extra-fine particle hydroalkane pressurized metered dose inhaled (pMDI) ciclesonide and beclomethasone dipropionate in children. A literature review was performed. Systemic bioavailability of oral and pulmonary deposition of extra-fine ciclesonide and beclomethasone dipropionate was 52% and 82%, the half-life in serum 3.2 and 1.5 h and first-pass hepatic metabolism >99% and 60%, respectively. Secondary analyses of urine cortisol/creatinine excretion found no effects of ciclesonide pMDI between 40 and 320 μg/day or of beclomethasone dipropionate pMDI between 80 and 400 μg/day. Ciclesonide pMDI 40, 80 and 160 μg/day caused no effects on short-term lower leg growth rate as assessed by knemometry. Ciclesonide 320 μg/day was associated with a numerically short-term growth suppression equivalent to 30% which was similar to 25% and 36% suppression caused by beclomethasone dipropionate HFA and CFC 200 μg/day, respectively. Consistent with the differences in key pharmacokinetic features, beclomethasone dipropionate is associated with a systemic activity detected by knemometry at a lower dose than ciclesonide. Whether that correlates with a clinically important difference remains to be explored. Assessments of systemic activity of beclomethasone dipropionate <200 μg/day and of ciclesonide >180 μg/day as well as head-to-head comparisons are warranted. Preferably, such studies should apply the sensitive method of knemometry.

The Evolution of Pressurized Metered-Dose Inhalers from Early to Modern Devices

Pressurized metered-dose inhalers (pMDIs) are sometimes viewed as old-fashioned and as having been superseded by dry powder inhalers (DPIs). Here, we review the technological advances that characterize modern pMDIs, and consider how they can influence the effectiveness of drug delivery for patients with asthma and chronic obstructive pulmonary disease. Compared with old chlorofluorocarbon (CFC)-based inhalers, many hydrofluoroalkane (HFA)-driven pMDIs have more favorable plume characteristics such as a reduced velocity and a higher fine particle fraction; together, these advances have resulted in the development of pMDIs with reduced oropharyngeal deposition and increased lung deposition. In addition, the plume from many HFA-pMDIs is warmer, which may facilitate their use by patients; moreover, devices are equipped with dose counters, which improves their reliability. As well as reviewing the technological advances of pMDIs, we also discuss the importance of individualizing inhaler therapies to each patient by accounting for their personal preferences and natural breathing patterns. Because pMDIs and DPIs differ considerably in their handling characteristics, matching the right inhaler to the right patient is key to ensuring effective therapy and good compliance. Finally, the majority of patients can be trained successfully in the correct use of their pMDI; training and regular monitoring of inhalation technique are essential prerequisites for effective therapy. While the 'ideal inhaler' may not exist, pMDIs are an effective device option suitable for many patients. pMDIs, together with other types of devices, offer opportunities for the effective individualization of treatments.

Small airway dysfunction and bronchial asthma control : the state of the art

According to national and international guidelines, achieving and maintaining asthma control is a major goal of disease management. In closely controlled clinical trials, good asthma control can be achieved , with the medical treatments currently available, in the majority of patients , but large population-based studies suggest that a significant proportion of patients in real-life setting experience suboptimal levels of asthma control and report lifestyle limitations with a considerable burden on quality of life. Poor treatment adherence and persistence, failure to use inhalers correctly, heterogeneity of asthma phenotypes and associated co-morbidities are the main contributing factors to poor disease control. Now, it is widely accepted that peripheral airway dysfunction , already present in patients with mild asthma, is a key contributor of worse control. The aim of this paper is to investigate the association between small-airways dysfunction and asthma symptoms/control. We therefore performed a PubMed search using keywords : small airways; asthma (limits applied: Humans, English language) and selected papers with a study population of asthmatic patients, reporting measurement of small-airways parameters and clinical symptoms/control.

Small-airway disease in asthma: pharmacological considerations

PURPOSE OF REVIEW

To review the pharmacological considerations and rationale for treating small-airway disease in asthma via the inhaled and systemic route, and to also directly address the comparison between small vs. large aerosol particles in the management of asthmatic patients.

RECENT FINDINGS

Airway inflammation in patients with asthma is predominantly present within the small airways and this region is the main contributor to airflow limitation. Assessing small-airway dysfunction has advanced in the last decade, allowing us to compare this region in disease to health and also in response to treatment. Recent pharmaceutical developments have led to inhaler devices with smaller aerosols and systemic biologic treatments, enabling therapeutic drug delivery to the distal lung regions. The question therefore is does targeting the small airways directly translate into health benefits for asthmatic patients with respect to an improvement in their disease control and quality of life?

SUMMARY

Studies now show that treating the peripheral airways with smaller drug particle aerosols certainly achieve comparable efficacy (and some studies show superiority) compared with large particles, a reduction in the daily inhaled corticosteroid dose, and greater asthma control and quality of life in real-life studies. Hence, the small airways should not be neglected when choosing the optimal asthma therapy.

Respiratory Tract Deposition of HFA-Beclomethasone and HFA-Fluticasone in Asthmatic Patients

BACKGROUND

The asthmatic patient's respiratory tract deposition of HFA fluticasone (Flovent HFA(™)) has not been established. There is a known large particle size difference with another commercial inhaled HFA steroid (QVAR(™)). This study compared the 2D and 3D respiratory tract deposition of each inhaled steroid.

METHODS

This study was an open label, crossover study in eight patients diagnosed with asthma. The regional respiratory and oropharyngeal deposition of the two steroids were compared and contrasted using planar and SPECT imaging following delivery of the (99m)Tc-radiolabeled drug in each product. The SPECT images were merged with computed tomography images to quantify regional deposition within the patients.

RESULTS

Two-dimensional (2D) planar images indicated that 24% of the Flovent HFA dose and 55% of the QVAR dose deposited in the lungs. 2D oropharyngeal deposition indicated that 75% of the Flovent HFA dose was deposited in the oropharynx, while 42% of the QVAR dose deposited in the oropharynx. Three-dimensional (3D) SPECT data indicated that 22% of the Flovent HFA dose and 53% of the QVAR dose deposited in the lungs. 3D oropharyngeal and gut deposition indicated 78% of the Flovent HFA dose was deposited in the oropharynx, while 47% of the QVAR dose deposited in the oropharynx. The increased lung deposition and decreased oropharynx deposition for both 2D and 3D image data of QVAR were statistically different from Flovent HFA.

CONCLUSIONS

QVAR exhibited a significant increase in lung delivery compared to Flovent HFA. Conversely, QVAR delivered a significantly lower dose to the oropharynx than Flovent HFA. The findings were presumed to be driven by the smaller particle size of QVAR (0.7 microns MMAD) compared with Flovent HFA (2.0 microns MMAD).

Plume Characteristics of Two HFA-Driven Inhaled Corticosteroid/Long-Acting Beta2-Agonist Combination Pressurized Metered-Dose Inhalers

INTRODUCTION

New inhalers propelled by hydrofluoroalkanes (HFAs) have improved plume characteristics: higher fine particle fraction, and warmer plumes with reduced force and velocity. Together, this may avoid reflex interruption of inhalation and improve lung deposition of the inhaled drugs. However, even with HFA-propelled pressurized metered-dose inhalers (pMDIs), there are notable differences in device properties. Here we compared the duration, velocity, force, and temperature of two inhaled corticosteroid/long-acting β2-agonist combination therapies, administered via HFA pMDIs: fluticasone propionate/formoterol 125/5 µg (FP/FORM; flutiform(®)) and fluticasone propionate/salmeterol 125/25 µg (FP/SAL; Seretide(®) Evohaler(®)).

METHODS

Inhalers were fired into ambient air. Plume duration and velocity were recorded with a high-speed camera and a pulsed laser light source. A copper disc attached to a sensitive load cell measured the plume force at various distances from the device. A thermal imaging video camera recorded impaction temperature in line with the device.

RESULTS

The average plume duration for FP/FORM was longer than that of FP/SAL: 168.3 vs. 114.0 ms, respectively. The mean maximum plume velocities observed at 95 mm (the approximate distance between mouthpiece and throat) was consistently slower for FP/FORM (10.08 m/s) compared to FP/SAL (15.55 m/s). FP/FORM had a slower velocity at the outset, remaining relatively constant before declining steadily over the plume duration. The force of the FP/SAL plume was greater than that of FP/FORM at all distances: maximum force for FP/FORM was 138.2 vs. 278.9 mN for FP/SAL. The minimum impaction temperature was +5.9 °C for FP/FORM and -37.8 °C for FP/SAL; this difference became less pronounced over distance.

CONCLUSION

There were substantial differences between the plumes of the two pMDIs. FP/FORM was warmer, less forceful, had a longer plume duration and slower maximal velocity. These plume characteristics of FP/FORM may lead to improved lung deposition.

FUNDING

Mundipharma Research Limited, Cambridge, UK.

Small-particle Inhaled Corticosteroid as First-line or Step-up Controller Therapy in Childhood Asthma

BACKGROUND

Because randomized controlled trials of established pediatric asthma therapies are expensive and difficult to perform, observational studies may fill gaps in the evidence base.

OBJECTIVES

To compare the effectiveness of representative small-particle inhaled corticosteroid (ICS) with that of standard size-particle ICS for children initiating or stepping up ICS therapy for asthma (analysis 1) and to compare the effectiveness of ICS dose step-up using small-particle ICS with adding long-acting β2-agonist (LABA) to the ICS (analysis 2).

METHODS

These historical matched cohort analyses drew on electronic medical records of children with asthma aged 5 to 11 years. Variables measured during 2 consecutive years (1 baseline year for confounder definition and 1 outcome year) included risk-domain asthma control (no hospital attendance for asthma, acute oral corticosteroids, or lower respiratory tract infection requiring antibiotics) and rate of severe exacerbations (asthma-related emergency, hospitalization, or oral corticosteroids).

RESULTS

In the initiation population (n = 797 in each cohort), children prescribed small-particle ICS versus standard size-particle ICS experienced greater odds of asthma control (adjusted odds ratio, 1.49; 95% CI, 1.10-2.02) and lower severe exacerbation rate (adjusted rate ratio, 0.56; 95% CI, 0.35-0.88). Step-up outcomes (n = 206 in each cohort) were also significantly better for small-particle ICS, with asthma control adjusted odds ratio of 2.22 (95% CI, 1.23-4.03) and exacerbations adjusted rate ratio of 0.49 (95% CI, 0.27-0.89). The number needed to treat with small-particle ICS to achieve 1 additional child with asthma control was 17 (95% CI, 9-107) for the initiation population and 5 (95% CI, 3-78) for the step-up population. Outcomes were not significantly different for stepped-up small-particle ICS dose versus ICS/LABA combination (n = 185 in each cohort).

CONCLUSIONS

Initiating or stepping up the ICS dose with small-particle ICS rather than with standard size-particle ICS is more effective and shows similar effectiveness to add-on LABA in childhood asthma.