A pilot study to assess lung deposition of HFA-beclomethasone and CFC-beclomethasone from a pressurized metered dose inhaler with and without add-on spacers and using varying breathhold times

Evaluating the pharmacokinetics of beclometasone dipropionate/formoterol fumarate/glycopyrronium bromide delivered via pressurised metered-dose inhaler using a low global warming potential propellant

INTRODUCTION

Use of propellants with high global warming potential (such as HFA-134a) for pressurised metered-dose inhalers (pMDIs) is being phased down. Switching to dry-powder inhalers may not be clinically feasible for all patients; an alternative is reformulation using propellants with low global warming potential. The combination of beclometasone dipropionate/formoterol fumarate/glycopyrronium bromide (BDP/FF/GB) is available for asthma or chronic obstructive pulmonary disease via pMDI using HFA-134a as propellant. This is being reformulated using the low global warming potential propellant HFA-152a. This manuscript reports three studies comparing BDP/FF/GB pharmacokinetics delivered via pMDI using HFA-152a vs HFA-134a.

METHODS

The studies were four-way crossover, single-dose, randomised, double-blind, in healthy volunteers. In Studies 1 and 2, subjects inhaled four puffs of BDP/FF/GB (Study 1: 100/6/12.5 μg [medium-strength BDP]; Study 2: 200/6/12.5 μg [high-strength]), ingesting activated charcoal in two of the periods (once per propellant). In Study 3, subjects inhaled medium- and high-strength BDP/FF/GB using a spacer. All three studies compared HFA-152a vs HFA-134a in terms of lung availability and total systemic exposure of beclometasone-17-monopropionate (B17MP; active metabolite of BDP), BDP, formoterol and GB. Bioequivalence was concluded if the 90 % confidence intervals (CIs) of the ratios between formulations of the geometric mean maximum plasma concentration (Cmax) and area under the plasma concentration-time curve between time zero and the last quantifiable timepoint (AUC0-t) for the analytes were between 80 and 125 %.

RESULTS

In Studies 1 and 2, systemic exposure bioequivalence (i.e., comparisons without charcoal block) was demonstrated, except for GB Cmax in Study 2 (upper 90 % CI 125.11 %). For lung availability (i.e., comparisons with charcoal block), B17MP and formoterol demonstrated bioequivalence in both studies, as did BDP in Study 2; in Study 1, BDP upper CIs were 126.96 % for Cmax and 127.34 % for AUC0-t). In Study 1, GB AUC0-t lower CI was 74.54 %; in Study 2 upper limits were 135.64 % for Cmax and 129.12 % for AUC0-t. In Study 3, the bioequivalence criteria were met for BDP, B17MP and formoterol with both BDP/FF/GB strengths, and were met for GB AUC0-t, although not for Cmax. Both formulations were similarly well tolerated in all three studies.

CONCLUSIONS

Overall, while formal bioequivalence cannot be concluded for all analytes, these data suggest therapeutic equivalence of the new formulation with the existing BDP/FF/GB pMDI formulation, therefore supporting reformulation using a propellant with low global warming potential.

The effect of lung emptying before the inhalation of aerosol drugs on drug deposition in the respiratory system

The amount of drug depositing in the airways depends, among others, on the inhalation manoeuvre and breathing parameters. The objective of this study was to quantify the effect of lung emptying before the inhalation of drugs on the lung doses. Thirty healthy adults were recruited. Their breathing profiles were recorded while inhaling through six different emptied DPI devices without breathe-out and after comfortable or forced exhalation. The corresponding emitted doses and aerosol size distributions were derived from the literature. The Stochastic Lung Model was used to estimate the deposited doses. In general, forceful exhalation caused increased flow rate and inhaled air volume. Increased flow rate led to the increase of the average lung dose for drugs with positive lung dose-flow rate correlation (e.g. Symbicort®: relative increase of 6.7%, Bufomix®: relative increase of 9.2%). For drugs with negative correlation of lung dose with flow rate (all the studied drugs except the above two) lung emptying caused increased (Foster® by 2.7%), almost unchanged (Seebri®, Relvar®, Bretaris®) and also decreased (Onbrez® by 6.6%) average lung dose. It is worth noting that there were significant inter-individual differences, and lung dose of each drug could be increased by a number of subjects. In conclusion, the change of lung dose depends on the degree of lung emptying, but it is also inhaler and drug specific. Forceful exhalation can help in increasing the lung dose only if the above specificities are taken into account.

[Diagnosis and treatment of asthma: a guideline for respiratory specialists 2023 - published by the German Respiratory Society (DGP) e. V.]

The management of asthma has fundamentally changed during the past decades. The present guideline for the diagnosis and treatment of asthma was developed for respiratory specialists who need detailed and evidence-based information on the new diagnostic and therapeutic options in asthma. The guideline shows the new role of biomarkers, especially blood eosinophils and fractional exhaled NO (FeNO), in diagnostic algorithms of asthma. Of note, this guideline is the first worldwide to announce symptom prevention and asthma remission as the ultimate goals of asthma treatment, which can be achieved by using individually tailored, disease-modifying anti-asthmatic drugs such as inhaled steroids, allergen immunotherapy or biologics. In addition, the central role of the treatment of comorbidities is emphasized. Finally, the document addresses several challenges in asthma management, including asthma treatment during pregnancy, treatment of severe asthma or the diagnosis and treatment of work-related asthma.

Assessing of low-tech solutions for aerosol delivery: Comparative performance study of manufactured versus homemade spacers

PURPOSE

This study aims to evaluate the performance of low-cost homemade spacers compared with manufactured valved holding chambers (VHCs) for fluticasone propionate delivery via a pMDI (pressurized Metered Dose Inhaler).

METHODS

The Total Emitted Dose (TED) and particle size distribution were measured for pMDI alone or connected to the different spacers, according to CAN/CSA-Z264.1-02 standard. Two types of low-cost alternative and manufactured spacers were investigated: 500 mL plastic bottle and 553 mL aluminium can; non-antistatic plastic VHCs and aluminium antistatic VHCs.

RESULTS

The TED of homemade plastic bottle vs plastic VHC were similar in the 20-23% range. In contrast, the TED of homemade aluminium can was higher compared to aluminium VHC (83% vs 68%). The Fine Particle Fraction (FPF) was similar for the two plastic-based spacers (in the 12.68-17.60% range), although it was greater for the aluminium can compared to aluminium VHC (51% vs 42%). However, all spacers have limited large particles fraction, mainly deposited in the oropharyngeal tract, potentially decreasing side effects.

CONCLUSION

We demonstrated that low-tech solutions as homemade spacers have at least similar performances to VHC medical devices composed of same material (aluminium or plastic). Thus, low-cost homemade spacers represent alternatives in case of emergency and without VHCs nearby.

In vitro-in vivo correlation of cascade impactor data for orally inhaled pharmaceutical aerosols

In vitro-in vivo correlation is the establishment of a predictive relationship between in vitro and in vivo data. In the context of cascade impactor results of orally inhaled pharmaceutical aerosols, this involves the linking of parameters such as the emitted dose, fine particle dose, fine particle fraction, and mass median aerodynamic diameter to in vivo lung deposition from scintigraphy data. If the dissolution and absorption processes after deposition are adequately understood, the correlation may be extended to the pharmacokinetics and pharmacodynamics of the delivered drugs. Correlation of impactor data to lung deposition is a relatively new research area that has been gaining recent interest. Although few in number, experiments and meta-analyses have been conducted to examine such correlations. An artificial neural network approach has also been employed to analyse the complex relationships between multiple factors and responses. However, much research is needed to generate more data to obtain robust correlations. These predictive models will be useful in improving the efficiency in product development by reducing the need of expensive and lengthy clinical trials.

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.

Evaluation of Bio-relevant Mouth-Throat Models for Characterization of Metered Dose Inhalers

For inhalation drug characterization, the traditionally used USP induction port provides limited in vivo predictive capability because it does not adequately mimic airway geometry. In this study, various bio-relevant mouth-throat (MT) models, including Alberta Idealized Throat (AIT), and 3D printed large/medium/small-sized VCU (Virginia Commonwealth University) models were evaluated using two metered dose inhaler (MDI) drug products: a solution MDI containing beclomethasone dipropionate (BDP-MDI) and a suspension MDI containing fluticasone propionate (FP-MDI). For BDP-MDI, use of VCU large and small MT models resulted in a significantly higher MT deposition and lower fine particle fraction (FPF) compared with the other MT models. In the case of FP-MDI, the three VCU models resulted in higher MT deposition and lower FPF compared with the USP induction port and AIT. Overall, the in vitro testing results for the suspension MDI were more sensitive to geometric differences of the MT models than those for the solution MDI. Our results suggest that in vitro characterization of MDI products can be influenced by many factors, including the type of formulation, the MT geometry, shape, internal space volume, and the material used to make the MT models.

What to consider before prescribing inhaled medications: a pragmatic approach for evaluating the current inhaler landscape

Inhaled therapies are the cornerstone of treatment in asthma and chronic obstructive pulmonary disease, and there are a multitude of devices available. There is, however, a distinct lack of evidence-based guidance for healthcare providers on how to choose an appropriate inhaler. This review aims to summarise recent updates on topics related to inhaler choice, and to offer practical considerations for healthcare providers regarding currently marketed devices. The importance of choosing the right inhaler for the right patient is discussed, and the relative merits of dry powder inhalers, pressurised metered dose inhalers, breath-actuated pressurised metered dose inhalers, spacers and soft mist inhalers are considered. Compiling the latest studies in the devices therapy area, this review focuses on the most common types of handling errors, as well as the comparative rates of incorrect inhalation technique between devices. The impact of device-specific handling errors on inhaler performance is also discussed, and the characteristics that can impair optimal drug delivery, such as inhalation flow rate, inhalation volume and particle size, are compared between devices. The impact of patient perceptions, behaviours and problems with inhalation technique is analysed, and the need for appropriate patient education is also highlighted. The continued development of technology in inhaler design and the need to standardise study assessment, endpoints and patient populations are identified as future research needs. The reviews of this paper are available via the supplemental material section.

Spacer devices for inhaled therapy: why use them, and how?

We present an extensive review of the literature to date pertaining to the rationale for using a spacer/valved holding chamber (VHC) to deliver inhaled therapy from a pressurised, metered-dose inhaler, a discussion of how the properties of individual devices may vary according to their physical characteristics and materials of manufacture, the potential risks and benefits of ancillaries such as valves, and the evidence that they contribute tangibly to the delivery of therapy. We also reiterate practical recommendations for the correct usage and maintenance of spacers/VHCs, which we trust offer practical help and advice to patients and healthcare professionals alike.

Optimizing the Delivery of Inhaled Medication for Respiratory Patients: The Role of Valved Holding Chambers

Valved holding chambers (VHCs) have been used with pressurized metered-dose inhalers since the early 1980s. They have been shown to increase fine particle delivery to the lungs, decrease oropharyngeal deposition, and reduce side effects such as throat irritation, dysphonia, and oral candidiasis that are common with use of pressurized metered-dose inhalers (pMDIs) alone. VHCs act as aerosol reservoirs, allowing the user to actuate the pMDI device and then inhale the medication in a two-step process that helps users overcome challenges in coordinating pMDI actuation with inhalation. The design of VHC devices can have an impact on performance. Features such as antistatic properties, effective face-to-facemask seal feedback whistles indicating correct inhalation speed, and inhalation indicators all help improve function and performance, and have been demonstrated to improve asthma control, reduce the rate of exacerbations, and improve quality of life. Not all VHCs are the same, and they are not interchangeable. Each pairing of a pMDI device plus VHC should be considered as a unique delivery system.

Scintigraphic Assessment of Deposition of Radiolabeled Fluticasone Delivered from a Nebulizer and Metered Dose Inhaler in 10 Healthy Dogs

Background

Aerosolized medications are increasingly being used to treat respiratory diseases in dogs. No previous studies assessing respiratory tract deposition of radiolabeled aerosols have been performed in conscious dogs.

Hypothesis/Objectives

Assess respiratory tract deposition of radiolabeled, inhalant corticosteroid (fluticasone propionate labeled with ^99mTc) delivered from a nebulizer and metered dose inhaler (MDI) to healthy dogs.

Animals

Ten healthy Foxhounds.

Methods

Prospective, randomized, cross‐over pilot study. Initial inhalation method (nebulizer or MDI) was randomly assigned. Treatments were crossed over after a 7‐day washout period. Treatments initially were performed using sedation. Dogs were imaged using 2‐dimensional planar scintigraphy, with respiratory tract deposition quantified by manual region‐of‐interest analysis. Deposition calculated as percentage of delivered dose. Six of 10 dogs were randomly selected and reassessed without sedation.

Results

Inhalation method had significant effect on respiratory tract deposition (P = 0.027). Higher deposition was achieved by nebulization with mean deposition of 4.2% (standard deviation [SD], 1.4%; range, 1.9–6.1%); whereas MDI treatment achieved a mean of 2.3% (SD, 1.4%; range, 0.2–4.2%). Nebulization achieved higher respiratory tract deposition than MDI in 7 of 10 dogs. No statistical difference (P = 0.68) was found between mean respiratory tract deposition achieved in dogs when unsedated (3.8%; SD, 1.5%) or sedated (3.6%; SD, 1.7%).

Conclusions and Clinical Importance

Study confirms respiratory tract deposition of inhalant medications delivered from a nebulizer and MDI in healthy dogs, breathing tidally with and without sedation. Respiratory tract deposition in these dogs was low compared to reported deposition in adult humans, but similar to reported deposition in children.

Short-Term Growth During Treatment with Inhaled Fluticasone Propionate/Formoterol, Fluticasone and Beclomethasone Treatment

BACKGROUND

Fluticasone propionate/formoterol (FP/FORM) is a pressurized metered-dose inhaler (pMDI; Flutiform^®) approved for use in adolescents and adults and under development for pediatric use.

OBJECTIVE

To compare short-term growth in asthmatic children treated with FP/FORM, FP pMDI with valved holding chamber, and beclomethasone dipropionate (BDP) in a breath-actuated device.

METHODS

Children with persistent asthma (n = 48; 5 to <12 years) participated in an assessor-blinded, randomized, three-way crossover trial with run in, wash out, and active treatment periods, each of 2 weeks duration. Interventions were FP/FORM 100/10 μg b.i.d. with an AeroChamber Plus^® Flow-Vu^® Spacer, FP pMDI (Flixotide^®) 100 μg b.i.d. with a Volumatic^® spacer, and extra-fine BDP breath-actuated inhaler (Aerobec^®/QVAR^® Autohaler^®) 100 μg b.i.d. Lower leg growth rate (LLGR) was measured by knemometry.

RESULTS

The least square (LS) mean difference in LLGR between FP/FORM and FP (per protocol population) was -0.006 mm/week (95% CI: -0.095 to 0.084; p < 0.001 for noninferiority [noninferiority margin -0.200 mm/week]). Both treatments elicited no change from baseline off-treatment growth rate. The LS mean treatment difference of FP/FORM versus BDP was 0.116 mm/week (95% CI: -0.004 to 0.235; p = 0.057) and of FP versus BDP 0.163 mm/week (95% CI: 0.078-0.249; p < 0.001). Results in the full analysis population were: FP/FORM versus FP -0.012 mm/week (95% CI: -0.080-0.056; p < 0.001); FP/FORM versus BDP 0.143 mm/week (95% CI: 0.064-0.222; p < 0.001); FP versus BDP 0.163 mm/week (95% CI: 0.093-0.233; p < 0.001).

CONCLUSIONS

FP/FORM pMDI with AeroChamber and FP pMDI with Volumatic spacer did not affect lower leg growth, measured by knemometry, in asthmatic children. Conversely, extra-fine BDP from a breath-actuated inhaler resulted in short-term growth suppression.

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.

Clinically Relevant In Vitro Testing of Orally Inhaled Products-Bridging the Gap Between the Lab and the Patient

Current pharmacopeial methods for in vitro orally inhaled product (OIP) performance testing were developed primarily to support requirements for drug product registration and quality control. In addition, separate clinical studies are undertaken in order to quantify safety and efficacy in the hands of the patient. However, both laboratory and clinical studies are time-consuming and expensive and generally do not investigate either the effects of misuse or the severity of the respiratory disease being treated. The following modifications to laboratory evaluation methodologies can be incorporated without difficulty to provide a better linkage from in vitro testing to clinical reality: (1) examine all types of OIP with patient-representative breathing profiles which represent normal inhaler operation in accordance with the instructions for use (IFU); (2) evaluate OIP misuse, prioritizing the importance of such testing on the basis of (a) probability of occurrence and (b) consequential impact in terms of drug delivery in accordance with the label claim; and (3) use age-appropriate patient-simulated face and upper airway models for the evaluation of OIPs with a facemask. Although it is not necessarily foreseen that these suggestions would form part of future routine quality control testing of inhalers, they should provide a closer approximation to the clinical setting and therefore be useful in the preparation for in vivo studies and in improving guidance for correct use.

Fixed-Dose combination of the inhaled corticosteroid and long-acting beta2-agonist therapy in adults with persistent asthma

INTRODUCTION

Asthma is a respiratory condition characterized by airway inflammation, airflow obstruction, and bronchial hyperresponsiveness. The standard treatment of asthma comprises inhaled corticosteroid and beta2-agonist. Inhaled short-acting-beta2-agonists have been used as rescue medication for exacerbation. However, long-acting-beta2-agonists (LABA) used as monotherapy for asthma had been reported for having a safety concern. Consequently, it had been recommended as an add-on treatment to inhaled corticosteroid (ICS) in moderate to severe persistent asthma. The fixed-dose combination (FDC) of ICS and LABA has been approved since the year 2000. Evidences revealed using the combination of these medications is more effective in asthma control.

AREAS COVERED

The rational and phase III onward randomized-controlled studies were reviewed. Sources of evidences were from studies published in Medline until November 2015.

EXPERT OPINION

There are six FDC inhaler regimens approved worldwide. The significant synergistic effects of ICS and LABA in one device are well evidenced. A FDC reduces the daily dosage of ICS and asthma exacerbation. It is safe to use regularly as controller. The efficacy of each individual combination on asthma treatment is generally similar. Clinical experience, ease of use, cost and side effects of medication would guide the clinician's preferences.

Effect of salmeterol/fluticasone combination on the dynamic changes of lung mechanics in mechanically ventilated COPD patients: a prospective pilot study

BACKGROUND

The combined therapy of inhaled corticosteroids and long-acting beta-2 agonists for mechanically ventilated patients with COPD has never been explored. Therefore, the aim of this study was to investigate their dynamic effects on lung mechanics and gas exchange.

MATERIALS AND METHODS

Ten mechanically ventilated patients with resolution of the causes of acute exacerbations of COPD were included. Four puffs of salmeterol 25 μg/fluticasone 125 μg combination therapy were administered. Lung mechanics, including maximum resistance of the respiratory system (Rrs), end-inspiratory static compliance, peak inspiratory pressure (PIP), plateau pressure, and mean airway pressure along with gas exchange function were measured and analyzed.

RESULTS

Salmeterol/fluticasone produced a significant improvement in Rrs and PIP after 30 minutes. With regard to changes in baseline values, salmeterol/fluticasone inhalation had a greater effect on PIP than Rrs. However, the therapeutic effects seemed to lose significance after 3 hours of inhaled corticosteroid/long-acting beta-2 agonist administration.

CONCLUSION

The combination of salmeterol/fluticasone-inhaled therapy in mechanically ventilated patients with COPD had a significant benefit in reducing Rrs and PIP.

Maintaining Control of Chronic Obstructive Airway Disease: Adherence to Inhaled Therapy and Risks and Benefits of Switching Devices

Asthma and chronic obstructive pulmonary disease (COPD) are major obstructive airway diseases that involve underlying airway inflammation. The most widely used pharmacotherapies for asthma and COPD are inhaled agents that have been shown to be effective and safe in these patients. However, despite the availability of effective pharmacologic treatment and comprehensive treatment guidelines, the prevalence of inadequately controlled asthma and COPD is high. A main reason for this is poor adherence. Adherence is a big problem for all chronic diseases, but in asthma and COPD patients there are some additional difficulties because of poor inhalation technique and inhaler choice. Easier-to-use devices and educational strategies on proper inhaler use from health caregivers can improve inhaler technique. The type of device used and the concordance between patient and physician in the choice of inhaler can also improve adherence and are as important as the drug. Adherence to inhaled therapy is absolutely necessary for optimizing patient control. If disease control is not adequate despite good adherence, switching to a more appropriate inhaled therapy is recommended. By contrast, uninformed switching or switching to less user-friendly inhaler may impact disease control negatively. This critical review of the available literature is aimed to provide a guidance protocol on when a switch may be recommended in individual patients.

In vitro characterization of the OptiChamber Diamond valved holding chamber

BACKGROUND

Use of a valved holding chamber (VHC) in conjunction with a pressurized metered dose inhaler (pMDI) can reduce issues relating to poor actuation-inhalation coordination and potentially improve the lung deposition of aerosol, compared with use of a pMDI alone. However, the performance of a VHC is influenced by different device-related factors, including the size and shape of the VHC and the material it is manufactured from (conventional versus antistatic). This study aimed to provide an in vitro characterization of an antistatic VHC, the OptiChamber Diamond VHC, comparing the aerodynamic particle size distribution of aerosol delivered via this VHC with results from a second antistatic VHC and a conventional VHC.

METHODS

The pMDI drug formulations (albuterol, suspension; beclomethasone dipropionate, solution) were connected to a Next Generation Impactor, either directly (pMDI alone tests) or via a VHC (VHC tests). The pMDIs were actuated (×10 per product pair) and tested at extraction flow rates of 15 L/min and 30 L/min, without any time delay between actuation and inhalation. Dose delivery using the two pMDI drug formulations was compared, and is presented with reference to key aerodynamic particle size parameters.

RESULTS

Compared with tests on pMDIs alone, use of a VHC increased the dose of aerosol within the respirable range, particularly at a 15 L/min flow rate. Between-VHC comparisons indicated that the two antistatic VHCs were equivalent. Delivery of albuterol appeared to be influenced by the VHC used, but beclomethasone dipropionate seemed unaffected.

CONCLUSIONS

The two antistatic VHCs were equivalent for both pMDI brands. Aerosol delivered from the antistatic VHCs at 15 L/min had a higher proportion of fine particles compared with the conventional VHC.

An Apparatus to Deliver Mannitol Powder for Bronchial Provocation in Children Under Six Years Old

BACKGROUND

Currently bronchial provocation testing (BPT) using mannitol powder cannot be performed in children under 6 years. A primary reason is it is challenging for children at this age to generate a consistent inspiratory effort to inhale mannitol efficiently from a dry powder inhaler. A prototype system, which does not require any inhalation training from the pediatric subject, is reported here. It uses an external source of compressed air to disperse mannitol powder into a commercial holding chamber. Then the subject uses tidal breathing to inhale the aerosol.

METHOD

The setup consists of a commercially available powder disperser and Volumatic™ holding chamber. Taguchi experimental design was used to identify the effect of dispersion parameters (flow rate of compressed air, time compressed air is applied, mass of powder, and the time between dispersion and inhalation) on the fine particle dose (FPD). The prototype was tested in vitro using a USP throat connected to a next generation impactor. The aerosols from the holding chamber were drawn at 10 L/min. A scaling factor for estimating the provoking dose to induce a 15% reduction in forced expiratory volume in 1 second (FEV1) (PD15) was calculated using anatomical dimensions of the human respiratory tract at various ages combined with known dosing values from the adult BPT.

RESULTS

Consistent and doubling FPDs were successfully generated based on the Taguchi experimental design. The FPD was reliable over a range of 0.8 (±0.09) mg to 14 (±0.94) mg. The calculated PD15 for children aged 1-6 years ranged from 7.1-30 mg. The FPDs generated from the proposed set up are lower than the calculated PD15 and therefore are not expected to cause sudden bronchoconstriction.

CONCLUSION

A prototype aerosol delivery system has been developed that is consistently able to deliver doubling doses suitable for bronchial provocation testing in young children.

How to match the optimal currently available inhaler device to an individual child with asthma or recurrent wheeze

Inhaled medications are the cornerstone of treatment in early childhood wheezing and paediatric asthma. A match between patient and device and a correct inhalation technique are crucial for good asthma control. The aim of this paper is to propose an inhaler strategy that will facilitate an inhaler choice most likely to benefit different groups of children. The main focus will be on pressurised metered dose inhalers and dry powder inhalers. In this paper we will discuss (1) practical difficulties with the devices and with inhaled therapy and (2) the optimal location for deposition of medicines in the lungs, and (3) we will propose a practical and easy way to make the best match between the inhaler device and the individual patient. We hope that this paper will contribute to an increased likelihood of treatment success and improved adherence to therapy.

Considerations for Designing In Vitro Bioequivalence (IVBE) Studies for Pressurized Metered Dose Inhalers (pMDIs) with Spacer or Valved Holding Chamber (S/VHC) Add-on Devices

BACKGROUND

The choice of analytical test methods and associated statistical considerations are considered for the laboratory testing of pressurized metered dose inhaler-spacer/valved holding chamber (pMDI-S/VHC) combinations for in vitro bioequivalence (IVBE).

METHODS

Four scenarios are presented for comparing TEST ("second entry" or "generic") versus REF ("innovator"): (1) innovator and second entry product pMDI alone without any S/VHC (baseline comparison); (2) innovator and second entry pMDI product with the same S/VHC; (3) innovator pMDI product with existing S/VHC and second entry product with a different S/VHC; and (4) introduction of a second, different S/VHC to be used with a given innovator pMDI product. The following aspects should be reviewed in the preparatory stage of designing experiments to establish IVBE: (a) the inclusion of delayed inhalation; (b) the utilization of age-appropriate flow rates; and (c) the use of anatomically appropriate face models for evaluation of devices with a facemask. Statistical considerations that fit in with such experimental methods include: selection of pMDI batches and S/VHC lots; choice of sample size and acceptance criteria; bracketing or worst case approaches; and balanced/paired designs. A stepwise approach for selection of impactor stage groupings is presented, and an approach to determine realistic acceptance criteria based on REF product characteristics is suggested.

RESULTS

An example of an efficient statistical design of experiment is provided for each scenario, together with alternate approaches for calculation of confidence intervals for the mean TEST/REF relationship. It is important to appreciate that the optimal design depends on balancing numerous considerations and will thus likely differ from case to case; hence, the designs presented here should be seen as illustrations rather than the only option available. More effective approaches may be found that suit a particular case at hand.

CONCLUSIONS

The information provided will assist in developing correlations in support of IVBE for these add-on devices.

Emerging inhalation aerosol devices and strategies: where are we headed?

Novel inhaled therapeutics including antibiotics, vaccines and anti-hypertensives, have led to innovations in designing suitable delivery systems. These emerging design technologies are in urgent demand to ensure high aerosolisation performance, consistent efficacy and satisfactory patient adherence. Recent vibrating-mesh and software technologies have resulted in nebulisers that have remarkably accurate dosing and portability. Alternatively, dry powder inhalers (DPIs) have become highly favourable for delivering high-dose and single-dose drugs with the aid of advanced particle engineering. In contrast, innovations are needed to overcome the technical constrains in drug-propellant incompatibility and delivering high-dose drugs with pressurised metered dose inhalers (pMDIs). This review discusses recent and emerging trends in pulmonary drug delivery systems.

Bronchodilation with mometasone furoate/formoterol fumarate administered by metered-dose inhaler with and without a spacer in children with persistent asthma

BACKGROUND

The bronchodilatory effect of mometasone furoate/formoterol fumarate (MF/F) administered by metered-dose inhaler (MDI) with or without a spacer has not been evaluated previously in children aged 5-11 years.

METHODS

This was a randomized, multicenter, placebo-controlled, single-dose, four-period crossover study. Children with persistent asthma aged 5-11 years participated in this study. Subjects used inhaled corticosteroids with/without long-acting beta-2 agonists for 12 weeks before enrollment and at screening had forced expiratory volume in 1 sec (FEV1 ) ≥70% predicted. Subjects received MF/F MDI 100/10 µg with/without spacer (AeroChamber Plus® with Flow-Vu® Anti-Static Valved Holding Chamber), F-Dry Powder Inhaler (F-DPI) 10 µg, and placebo MDI with/without spacer in separate treatment periods. The primary endpoint was FEV1 area under the curve from 0 to 12 hr (AUC0-12hr ) for the comparison of MF/F with spacer versus placebo. Secondary measurements included MF/F without spacer versus placebo, as well as MF/F with spacer versus MF/F without spacer, and F-DPI versus placebo. Analysis was performed with an analysis of covariance model for a crossover study.

RESULTS

Data from 87 subjects were analyzed. MF/F with spacer demonstrated a larger change in mean FEV1 AUC0-12hr versus placebo (115 vs. -9 mL), with a treatment difference of 124 mL (95% CI 94-154, P < 0.001). Similarly, MF/F without spacer versus placebo resulted in a 102 mL difference in mean-adjusted FEV1 AUC0-12hr (95% CI 73-131, P < 0.001), whereas the difference between MF/F with spacer versus MF/F without spacer was 22 mL (95% CI -8 to 52, P = 0.144). The difference between F-DPI versus placebo was 106 mL (95% CI 77-135, P < 0.001). No unexpected adverse events were observed.

CONCLUSIONS

In this trial, MF/F MDI 100/10 µg demonstrated significant bronchodilation in children aged 5-11 years regardless of the use of a spacer. No difference in bronchodilation was observed between MF/F MDI and F-DPI.

Handling of Diskus dry powder inhaler in Chinese chronic obstructive pulmonary disease patients

BACKGROUND

The incorrect handling of Diskus inhalers in Chinese patients with chronic obstructive pulmonary disease (COPD) is not well documented.

OBJECTIVE

The present study was conducted to evaluate in detail the handling errors related to the Diskus device, and to elucidate the importance of educating COPD patients on the proper use of the device.

METHODS

A total of 384 COPD patients from a pulmonary clinic in China over a period of 5 years were included in the study. The compliance of COPD patients to the 13 discrete steps of Diskus usage were scored and analyzed by three measures: (1) On day 0, patients were given only a package insert on Diskus, and the handling error rate was assessed. Then the patients were given instruction on the 13-step Diskus procedure until they could demonstrate the proper technique. (2) On days 1, 2, and 3, the observation group was continuously educated on a 13-step procedure, and the percentage of patients who scored 100% for each step was recorded. The control group had no such training. (3) On days 10, 20, and 30, the percentage of all subjects correctly performing the Diskus 13-step inhalation procedure was assessed.

RESULTS

Incorrect handling techniques on Diskus usage were widely distributed among Chinese COPD patients. Step 8 ("Inhale forcefully from the beginning, slowly, deeply, and uniformly during the inspiratory phase until the lungs are full") was the most commonly mishandled step (93.8%). The total score and individual step scores of the patients from the observation group were significantly improved during 3-day continuous education. There was also a significantly higher percentage of correctly performed steps in the observation group than in the control group upon assessment on day 10 (96.24% vs. 85.63%, respectively; p<0.01), day 20 (97.31% vs. 86.09%, respectively; p<0.01), and day 30 (98.19% vs. 87.39%, respectively; p<0.01).

CONCLUSION

Handling errors of the Diskus 13-step inhalation procedure were commonly observed in Chinese COPD patients. Continuous educational interventions and regular supervision by health-care providers are therefore crucial for the optimum use of the Diskus inhaler.

Improved laboratory test methods for orally inhaled products

Existing pharmacopeial methods for the in vitro testing of orally inhaled products (OIPs) are simplified representations of clinical reality, as their objective is to provide metrics that are discriminating of product quality. Attempts to correlate measures such as fine particle fraction <5 µm aerodynamic diameter with in vivo measures of lung deposition have therefore been notoriously difficult to achieve. Although particle imaging-based techniques may be helpful to link in vitro to in vivo data as surrogates for clinical responses, a reappraisal of the purposes for laboratory-based testing of OIPs is required. This article provides guidance on approaches that may be helpful to develop clinically appropriate methods to assess OIP performance in the laboratory, with the ultimate goal of developing robust in vitro–in vivo relationships for the major inhaled drug classes.

New therapeutic options for allergic rhinitis: back to the future with intranasal corticosteroid aerosols

BACKGROUND

Under current guidelines, intranasal corticosteroids (INSs) are considered the most effective first-line therapy to improve allergic rhinitis (AR) symptoms and burden of disease. In the late 1980s-1990s, chlorofluorocarbon (CFC)-propelled corticosteroid aerosol nasal sprays formed the standard of care for the treatment of AR. Because of environmental concerns, CFC aerosols were gradually phased out, and aqueous INS formulations of nasal sprays became the standard of care. Although many aqueous INS sprays are available, specific product-related factors can reduce patient adherence to an INS and subsequently reduce treatment efficacy. The purpose of this paper was to review the evolution of AR therapeutics and drug devices and how it may have an effect on patient adherence/compliance and patient satisfaction with current available therapies and show the unmet need to improve INS delivery systems.

METHODS

Although aqueous INSs are effective and well tolerated, use in some patients may be compromised because of patient sensory perception and device preference. A historical review of the evolution of intranasal delivery of INSs was undertaken to provide further insight into improving treatment options for patients with AR.

RESULTS

Although the various approved INSs appear to be equivalent in terms of reducing AR disease burden, the method in which an INS is delivered to a patient has significant bearing on the overall success of each specific drug product.

CONCLUSION

Hydrofluoroalkane-propelled INS drug products offer a back-to-the-future delivery approach that may be further tailored to the individual patient's needs. Past experiences and the development of new devices are paving the way toward further therapy choices, ultimately affording health care providers access to the most effective treatments for patients with AR.

Inhaled corticosteroid metered-dose inhalers: how do variations in technique for solutions versus suspensions affect drug distribution?

OBJECTIVE

To assess the literature that evaluates how variations in metered-dose inhaler (MDI) technique affect lung distribution for inhaled corticosteroids (ICSs) formulated as MDI suspensions and solutions.

DATA SOURCES

PubMed (up to November 2012) and Cochrane Library (up to November 2012) were searched using the terms metered-dose inhalers, HFA 134a, Asthma/*drug therapy, and inhaled corticosteroids. In addition, reference citations from publications identified were reviewed.

STUDY SELECTION AND DATA EXTRACTION

All articles in English from the data sources that assessed MDI technique comparing total lung distribution (TLD) of MDI solutions or suspensions formulated with ICSs were included in the review. Five relevant studies were identified.

DATA SYNTHESIS

Five controlled studies compared how variations in MDI technique affect TLD for ICS MDI solutions with suspensions. MDI solutions resulted in greater TLD compared with larger particle MDI suspensions. Delayed or early inspiration upon device actuation of MDI solutions resulted in less TLD than coordinated actuation, but with a 3- to 4-times greater TLD than MDI suspensions inhaled using a standard technique. A sixth study evaluated inspiratory flow rates (IFR) for small, medium, and large particles. Rapid and slow IFRs resulted in similar TLD for small particles, while far fewer particles reached the airways with medium and large particles at rapid, rather than slow, IFRs.

CONCLUSIONS

Based on the literature evaluated, standard MDI technique should be used for ICS suspensions. ICS MDI solutions can provide a higher average TLD than larger-particle ICS suspensions using standard technique, discoordinated inspiration and medication actuation timing, or rapid and slow IFRs. ICS MDI solutions allow for a more forgiving technique, which makes them uniquely suitable options for patients with asthma who have difficultly with MDI technique.

The use of computational fluid dynamics in inhaler design

INTRODUCTION

Computational fluid dynamics (CFD) has recently seen increased use in the design of pharmaceutical inhalers. The use of CFD in the design of inhalers is made difficult by the complex nature of aerosol generation. At present, CFD has provided valuable insight into certain aspects of inhaler performance, though limitations in computational power have prevented the full implementation of numerical methods in the design of inhalers.

AREAS COVERED

This review examines the application of CFD in the design of aerosol drug delivery technologies with a focus on pressurized metered-dose inhalers (pMDI), nebulizers and dry powder inhalers (DPIs). Challenges associated with the application of CFD in inhaler design are discussed along with relevant investigations in the literature. Discussions of discrete element modeling (DEM) and the simulation of pharmaceutical aerosol dispersion are included.

EXPERT OPINION

The extreme complexity of coupled fluid and aerosol dynamics associated with aerosol generation has somewhat limited the use of CFD in inhaler design. Combined CFD--DEM simulations provide a useful tool in the design of DPIs, though aerosol generation in pMDIs and nebulizers has eluded CFD modeling. The most beneficial use of CFD typically occurs when concurrent CFD and experimental analyses are performed, significantly enhancing the knowledge provided by experiment alone.

Comparative in vitro performance of three small-volume valved holding chambers with beclomethasone/formoterol pressurized metered dose inhaler

BACKGROUND

The use of valved holding chambers (VHCs) with pressurized metered dose inhalers (pMDIs) is reported to reduce the oral deposition of inhaled drugs and to facilitate the handling of these devices by patients, especially children. Although the number of commercially available VHCs is increasing, the correct choice of VHC in clinical practice is important, because VHCs are not equally effective regarding medication delivery. Hence, we aimed to evaluate the use of three small-volume VHCs-Vortex(®), AeroChamber(®) Plus (ACP), and Able Spacer™ (AS)-along with a commercial pMDI containing a combination of beclomethasone and formoterol (Innovair(®)) frequently used by asthma patients.

METHODS

Evaluation of the delivered dose of both drugs and analysis of particle size distribution of aerosols emitted for the inhaler were performed using the Next Generation Impactor with and without the tested VHCs.

RESULTS

The VHCs retained significant quantities of both drugs and dramatically reduced the quantity of drugs deposited in the throat of the impactor, indicating that particles with large size were preferably retained in the VHCs. Interestingly, although the delivered dose of both drugs was reduced by the use of VHCs, the use of the Vortex and the ACP resulted in comparable fine particle doses (FPDs) to that obtained when the pMDI was used alone, whereas the AS VHC significantly reduced the FPDs of both drugs. This may be due to the fact that, unlike the AS VHC, the Vortex and the ACP VHCs are made of antistatic materials that minimize the electrostatic interaction with emitted aerosols, enhancing medication delivery.

CONCLUSION

The Vortex and the ACP VHCs present interesting advantages over the AS VHC to be used with Innovair pMDI. However, these results are based on an in vitro evaluation and need to be validated in an in vivo study in order to clinically assess the performance of these VHCs.

Characterization of respiratory deposition of fluticasone-salmeterol hydrofluoroalkane-134a and hydrofluoroalkane-134a beclomethasone in asthmatic patients

BACKGROUND

Fixed combination fluticasone-salmeterol is the most used anti-inflammatory asthma treatment in North America, yet no studies report the actual respiratory tract dose or the distribution of drug within the lungs. Inflammation due to asthma affects all airways of the lungs, both large and small. Inhaled steroid delivery to airways results from a range of drug particle sizes, with emphasis on smaller drug particles capable of reaching the peripheral airways. Previous studies suggested that smaller drug particles increase pulmonary deposition and decrease oropharyngeal deposition.

OBJECTIVES

To characterize the dose of fluticasone-salmeterol hydrofluoroalkane-134a (HFA) (particle size, 2.7 μm) delivered to asthmatic patients and examine the drug distribution within the lungs. The results were compared with the inhalation delivery of HFA beclomethasone (particle size, 0.7 μm).

METHODS

A crossover study was conducted in asthmatic patients with commercial formulations of fluticasone-salmeterol and HFA beclomethasone radiolabeled with technetium Tc 99m. Deposition was measured using single-photon emission computed tomography/computed tomography gamma scintigraphy.

RESULTS

Two-dimensional planar image analysis indicated that 58% of the HFA beclomethasone and 16% of the fluticasone-salmeterol HFA were deposited in the patient's lungs. The oropharyngeal cavity and gut analyses indicated that 77% of the fluticasone-salmeterol HFA was deposited in the oropharynx compared with 35% of the HFA beclomethasone.

CONCLUSIONS

The decreased peripheral airway deposition and increased oropharyngeal deposition of fluticasone-salmeterol HFA was a result of its larger particle size. The smaller particle size of HFA beclomethasone allowed a greater proportion of lung deposition with a concomitant decrease in oropharyngeal deposition.

[Inhalation devices: characteristics, modeling, regulation and use in routine practice. GAT Aerosolstorming, Paris 2011]

Aerosoltherapy is a first-line treatment for chronic obstructive respiratory diseases such as asthma and COPD. Treatment modalities and devices are varied and the choice of the device must be adapted to and optimized for every patient. Spacers can be used for some categories of patients for whom the use of other devices turns out to be complicated. The improvement of these treatments requires the optimization of the lung deposition of inhaled particles; lung modeling plays an essential role in the understanding of the mechanisms of flow in the airways. Regulations must frame prescription of inhaled treatments to optimize its quality and, thus, the care for these chronic diseases. Many generally-accepted ideas concerning these treatments turn out to be false. Inhaled treatments are constantly evolving, both pharmacologically and technologically.

Updates on the use of inhaled corticosteroids in asthma

PURPOSE OF REVIEW

The purpose of this review is to compare and contrast the newer inhaled corticosteroid (ICS) ciclesonide with older ICSs in terms of pharmacodynamic and pharmacokinetic properties and how these affect comparative efficacy. In addition, clinical dosing strategies for ICSs including as-needed use will be explored.

RECENT FINDINGS

Ciclesonide has demonstrated similar efficacy to that of fluticasone propionate and mometasone furoate in equipotent doses with a potentially improved therapeutic index. Once-daily administration of ICSs is generally not as effective as twice-daily. Continuous administration of ICSs does not change the natural history of asthma in either children or adults. Long-term administration of medium dose ICSs does not increase the risk of cataracts or osteopenia in children and young adults. Studies of as-needed ICSs in mild persistent asthma in adults and children have demonstrated mixed results, with some showing equal efficacy to continuous therapy and others showing superiority of continuous therapy.

SUMMARY

Ciclesonide provides a newer ICS with favorable pharmacokinetics that may improve the therapeutic index, but assessment of its systemic effects such as growth await further studies. Continuous administration of ICSs in low to medium dose over many years is well tolerated. The use of as-needed ICSs in patients with mild persistent asthma is promising as a potential step-down therapy but awaits further studies.

Targeting small airways, a step further in asthma management

INTRODUCTION

During the last decade, small airway (SA) involvement in asthma and Chronic Obstructive Pulmonary Disease (COPD) have reached increasing attention. Originally referred to as the 'silent zone', SA may not be that silent after all. Important clinical correlates are asthma exacerbations and airways remodelling, exercise asthma and nocturnal asthma. Thus, to control pathology in the SA has become a desirable goal in asthma management.

OBJECTIVES

The scope of this review is to give a brief overview of the current status on SA in asthma, how to monitor and to diagnose SA inflammation and finally highlight some important treatment strategies.

RESULTS/CONCLUSION

New tools have been developed to monitor SA function; these implies the use of imaging techniques and respiratory physiology, targeting SA function. Fractional exhaled nitric oxide and the combined use of hyperresponsiveness testing with impulsoscillometry is another option. The introduction of ultrafine aerosols has provided new tools for to treat SA inflammation. The challenge for the future will be to define the optimal particle size and device for maximal deposition in entire lung, including the small airways. Moreover, we also need strategies for increasing the therapeutic ratio, i.e. increasing lung deposition without increasing systemic side effects. Another challenge is to design and to perform clinical trials, targeting effects in SA, proving the clinical importance of SA treatment in a large number of patients. The latter also imply education of our medical authorities, communicating that asthma is more than a beta-2 agonist responsive central airway disorder of the lungs.