The Diskus: a review of its position among dry powder inhaler devices

Once-daily fluticasone furoate/vilanterol vs once-daily fluticasone furoate in patients with asthma aged 5 to 17 years

BACKGROUND

Limited data exist comparing inhaled corticosteroid (ICS) plus adjunctive therapy vs ICS alone in pediatric asthma patients.

OBJECTIVE

To evaluate the efficacy and safety of fluticasone furoate/vilanterol (FF/VI) vs FF in children and adolescents with asthma.

METHODS

This phase 3, randomized, double-blind, multicenter study (NCT03248128) included participants aged 5 to 17 years with six months or more asthma history uncontrolled on ICS monotherapy. Participants received 4-week open-label fluticasone propionate (100 µg) twice daily before 1:1 randomization to 24-week double-blind FF (50 µg:100 µg) or FF/VI (50/25 µg:100/25 µg) once daily. Two populations with different primary endpoints were analyzed to meet United States (week 12 weighted mean forced expiratory volume in 1 second [FEV1; 0-4 hours]; participants aged 5-17 years) and European (change from baseline predose morning peak expiratory flow [ΔAM PEF] averaged over weeks 1-12; participants aged 5-11 years) regulatory requirements.

RESULTS

Overall, 902 participants, including 673 children aged 5 to 11 years, were randomized and treated. In participants aged 5 to 17, week 12 weighted mean FEV1 (0-4 hours) was greater with FF/VI vs FF (difference: 0.083 L; P < .001). In participants aged 5 to 11, ΔAM PEF over weeks 1 to 12 showed numerical improvement with FF/VI vs FF but was not statistically significant (difference: 3.2 L/min; P = .228). No drug-related serious adverse events or deaths were reported.

CONCLUSION

FF/VI significantly improved weighted mean FEV1 (0-4 hours; participants aged 5-17 years), but not ΔAM PEF (participants aged 5-11 years) vs FF. No new safety concerns were apparent.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03248128.

Mapping the evolution of inhaled drug delivery research: Trends, collaborations, and emerging frontiers

Inhaled drug delivery is a unique administration route known for its ability to directly target pulmonary or brain regions, facilitating rapid onset and circumventing the hepatic first-pass effect. To characterize current global trends and provide a visual overview of the latest trends in inhaled drug delivery research, bibliometric analysis of data acquired from the Web of Science Core Collection database was performed via VOSviewer and CiteSpace. Inhaled drug delivery can not only be utilized in respiratory diseases but also has potential in other types of diseases for both fundamental and clinical applications. Overall, we provide an overview of present trends, collaborations, and newly discovered frontiers of inhaled drug delivery.

Understanding the effects of inhaler resistance on particle deposition behaviour - A computational modelling study

BACKGROUND AND OBJECTIVE

Understanding the impact of inhaler resistance on particle transport and deposition in the human upper airway is essential for optimizing inhaler designs, thereby contributing to the enhancement of the therapeutic efficacy of inhaled drug delivery. This study demonstrates the potential effects of inhaler resistance on particle deposition characteristics in an anatomically realistic human oropharynx and the United States Pharmacopeia (USP) throat using computational fluid dynamics (CFD).

METHOD

Magnetic resonance (MR) imaging was performed on a healthy volunteer biting on a small mockup inhaler mouthpiece. Three-dimensional geometry of the oropharynx and mouthpiece were reconstructed from the MR images. CFD simulations coupled with discrete phase modelling were conducted. Inhaled polydisperse particles under two different transient flow profiles with peak inspiratory flow rates (PIFR) of 30 L/min and 60 L/min were investigated. The effect of inhaler mouthpiece resistance was modelled as a porous medium by varying the initial resistance (Ri) and viscous resistance (Rv). Three resistance values, 0.02 kPa0.5minL-1, 0.035 kPa0.5minL-1 and 0.05 kPa0.5 minL-1, were simulated. The inhaler outlet velocity was set to be consistent across all models for both flow rate conditions to enable a meaningful comparison of models with different inhaler resistances.

RESULT

The results from this study demonstrate that investigating the effect of inhaler resistance by solely relying on the USP throat model may yield misleading results. For the geometrically realistic oropharyngeal model, both the pressure and kinetic energy profiles at the mid-sagittal plane of the airway change dramatically when connected to a higher-resistance inhaler. In addition, the geometrically realistic oropharyngeal model appears to have a resistance threshold. When this threshold is surpassed, significant changes in flow dynamics become evident, which is not observed in the USP throat model. Furthermore, this study also reveals that the impact of inhaler resistance in a geometrically realistic throat model extends beyond the oral cavity and affects particle deposition downstream of the oral cavity, including the oropharynx region.

CONCLUSION

Results from this study suggest that key mechanisms underpinning the working principles of inhaler resistance are intricately connected to their complex interaction with the pharynx geometry, which affects the local pressure, local variation in velocity and kinetic energy profile in the airway.

In Vitro Comparison of Two Blister-Type Inhalers

BACKGROUND

Ellipta is a respiratory device that is a successor of the Diskus. A major difference between the devices is that Ellipta, especially the 2-strip type, includes a pair of blisters rather than a single blister as contained in Diskus. This study aimed to compare the particle-release properties and mechanical features of both devices.

METHODS

A pump was used to evacuate air from each dry powder inhaler (DPI) with either a ramp-up or triangular pattern. The particle release volume and peak inspiratory flow of the DPIs were compared. Then the resistance of each component was measured.

RESULTS

Both DPIs required specific threshold flows for particle release. Inspiratory flows exceeding the threshold values (Ellipta 11.3 ± 4.0 L/min and Diskus 29.7 ± 4.7 L/min using ramp-up inhalations; Ellipta 10.6 ± 2.1 L/min and Diskus 28.4 ± 5.2 L/min using triangular ones) did not further increase particle release volumes. The inspiratory flows required for Ellipta were significantly less than those for Diskus. The particle release volume exceeding threshold flow for Ellipta was approximately 2.62 (ramp-up) and 2.01 (triangular) times those of Diskus. The resistance of one blister was similar (0.44 cm H2O/L/min vs 0.42 cm H2O/L/min for Ellipta and Diskus, respectively). As Ellipta includes 2 parallel blisters, similar resistances suggest that Ellipta requires twice the flow of Diskus. The flow distributions for particle release in Ellipta and Diskus were 35.3 and 5.2% of the total inspiratory flow, respectively.

CONCLUSIONS

The Ellipta required lower inspiratory flow than Diskus, which arises from a higher distribution to blister flow. Ellipta may be preferable to Diskus for patients with impaired pulmonary function.

Advancements in the Design and Development of Dry Powder Inhalers and Potential Implications for Generic Development

Dry powder inhalers (DPIs) are drug-device combination products where the complexity of the formulation, its interaction with the device, and input from users play important roles in the drug delivery. As the landscape of DPI products advances with new powder formulations and novel device designs, understanding how these advancements impact performance can aid in developing generics that are therapeutically equivalent to the reference listed drug (RLD) products. This review details the current understanding of the formulation and device related principles driving DPI performance, past and present research efforts to characterize these performance factors, and the implications that advances in formulation and device design may present for evaluating bioequivalence (BE) for generic development.

Scientific and regulatory activities initiated by the U.S. food and drug administration to foster approvals of generic dry powder inhalers: Quality perspective

Regulatory science for generic dry powder inhalation products worldwide has evolved over the last decade. The revised draft guidance Metered Dose Inhaler (MDI) and Dry Powder Inhaler (DPI) Products - Quality Considerations [1] (Revision 1, April 2018) that FDA issued summarizes product considerations and potential critical quality attributes (CQAs). This guidance emphasizes the need to apply the principles of quality by design (QbD) and elements of pharmaceutical development discussed in the International Conference for Harmonisation of (ICH) guidelines. Research studies related to quality were used to support guidance recommendations, which preceded the first approval of a generic DPI product in the U.S. This review outlines scientific and regulatory hurdles that need to be surmounted to successfully bring a generic DPI to the market. The goal of this review focuses on relevant issues and various challenges pertaining to CMC topics of the generic DPI quality attributes. Furthermore, this review provides recommendations to abbreviated new drug application (ANDA) applicants to expedite generic approvals.

Dry powder inhalation, part 2: the present and future

INTRODUCTION

The manufacture of modern dry powder inhalers (DPIs), starting with the Spinhaler (Fisons) in 1967, was only possible thanks to a series of technological developments in the 20^th century, of which many started first around 1950. Not until then, it became possible to design and develop effective, cheap and mass-produced DPIs. The link between these technological developments and DPI development has never been presented and discussed before in reviews about the past and present of DPI technology.

AREAS COVERED

The diversity of currently used DPIs with single dose, multiple-unit dose and multi-dose DPIs is discussed, including the benefits and drawbacks of this diversity for correct use and the efficacy of the therapy. No specific databases or search engines otherwise than PubMed and Google have been used.

EXPERT OPINION

Considering the relatively poor efficacy regarding lung deposition of currently used DPIs, the high rates of incorrect inhaler use and inhalation errors and the poor adherence to the therapy with inhalers, much effort must be put in improving these shortcomings for future DPI designs. Delivered fine particle doses must be increased, correct inhaler handling must become more intuitive and simpler to perform, and the use of multiple inhalers must be avoided.

Pilot Study to Investigate the Benefits of the InnoSpire Go Mesh Nebulizer Compared to Jet Nebulizers in the Treatment of Stable COPD

Background: Nebulizers are widely used for the delivery of aerosols to patients with chronic obstructive pulmonary disease (COPD). The InnoSpire Go mesh nebulizer has been designed to improve upon the ease of use and convenience of existing nebulizers for the treatment of COPD. Methods: This was a pilot, single-center, randomized, open-label crossover study conducted over 2 months to investigate the use of the InnoSpire Go mesh nebulizer compared to the patient's own compressor driven jet nebulizer in ambulatory patients with stable COPD. Patient preference was assessed at the end of the study; quality of life, symptom scores, treatment time, and satisfaction were assessed at multiple points during the study. Results: Data for 17 patients were eligible for analysis, patients had a mean age of 64.6 years, and 64.7% were graded 3 on the modified Medical Research Council dyspnea scale. All patients preferred the InnoSpire Go mesh nebulizer over their own compressor driven jet nebulizer (p < 0.001). Nebulization of study drugs using the InnoSpire Go mesh nebulizer was associated with statistically significant increases in health-related quality of life over baseline (Dyspnea p = 0.003, Emotion p = 0.043, Mastery p = 0.011). A mixed model analysis of Borg dyspnea scores before and after exercise showed significantly (p = 0.043) lower scores for the InnoSpire Go mesh nebulizer compared with the compressor driven nebulizers. Patient satisfaction was statistically significantly higher for each of 10 questions covering ease of use, confidence, burden of use, satisfaction, and how well the device fit into their lifestyle. Treatment time was significantly shorter with the InnoSpire Go mesh nebulizer (p = 0.003). Conclusions: Patients preferred and were more satisfied with the InnoSpire Go mesh nebulizer. Nebulization of study drugs using the InnoSpire Go mesh nebulizer resulted in improved quality of life compared with baseline, and treatments were delivered in a shorter period than the compressor driven jet nebulizers. Clinical Trial Registration number: ClinicalTrials.gov: NCT03933462.

A Quality by Design Framework for Capsule-Based Dry Powder Inhalers

Capsule-based dry powder inhalers (cDPIs) are widely utilized in the delivery of pharmaceutical powders to the lungs. In these systems, the fundamental nature of the interactions between the drug/formulation powder, the capsules, the inhaler device, and the patient must be fully elucidated in order to develop robust manufacturing procedures and provide reproducible lung deposition of the drug payload. Though many commercially available DPIs utilize a capsule-based dose metering system, an in-depth analysis of the critical factors associated with the use of the capsule component has not yet been performed. This review is intended to provide information on critical factors to be considered for the application of a quality by design (QbD) approach for cDPI development. The quality target product profile (QTPP) defines the critical quality attributes (CQAs) which need to be understood to define the critical material attributes (CMA) and critical process parameters (CPP) for cDPI development as well as manufacturing and control.

Usability and Robustness of the Wixela Inhub Dry Powder Inhaler

Background: Wixela Inhub is a generic version of Advair Diskus recently approved by the U.S. Food and Drug Administration. The Inhub inhaler delivers fluticasone propionate (FP)/salmeterol in a dry powder formulation. The goals of our studies were to demonstrate that the Inhub inhaler can be used by representative end users and confirm the robustness of the Inhub inhaler. Methods: Study 1: A nondosing usability assessment, the device orientation study, confirmed that intended users (represented by patients diagnosed with asthma or chronic obstructive pulmonary disease [COPD] who were naive to dry powder inhalers and current Advair Diskus users) could use the Inhub inhaler safely and effectively. Subjects were provided with an Inhub inhaler in commercial packaging, including instructions for use, and were asked to undertake three dose simulations using the inhaler. Subjects were encouraged to interact with this new drug delivery device as they would at home. Subjects were not provided with training on the use of the device. Subjects were observed interacting with the Inhub inhaler, and those who currently use Diskus were also observed interacting with the Diskus to determine whether their mental model of the use of Diskus impacted their interaction with the Inhub device, this assessment was not a primary outcome of the study. Study 2: This is an open-label clinical study to confirm the robustness of the Inhub inhaler after at home patient use. Subjects diagnosed with asthma or COPD were provided Inhub inhaler training and subsequently self-administered 3 weeks of twice daily doses of Wixela Inhub 250 μg FP/50 μg salmeterol in the home environment. The Inhub inhalers were returned to the investigator after ∼3 weeks of outpatient use for in vitro tests on the drug remaining in each inhaler. Results: Study 1 enrolled 110 subjects, and all completed the study. Most subjects (100/110) held the Inhub inhaler in the correct orientation and of those who did not, 9 still achieved a peak inhalation flow rate of ≥30 L/min and a total inhaled volume of ≥1 L, thus meeting the requirements of the study success criteria. In Study 2, 111 pediatric, adult, and elderly subjects with asthma or COPD received the study drug. After ∼3 weeks of outpatient use of the Inhub inhaler by subjects, comprehensive in vitro testing demonstrated that the FP and salmeterol pharmaceutical performance in the Inhub inhaler was preserved. Conclusions: The majority of subjects demonstrated safe and effective use of the Inhub inhaler. In vitro testing and inspections confirmed the robustness of the Inhub inhaler after outpatient use. Clinical trial registration number: NCT02474017.

Emerging trends in inhaled drug delivery

Ideally, inhaled therapy is driven by the needs of specific disease management. Lung biology interfaces with inhaler performance to allow optimal delivery of therapeutic agent for disease treatment. Inhalation aerosol products consist of the therapeutic agent, formulation, and device. The manufacturing specifications on each of the components, and their combination, allow accurate and reproducible control of measures of quality and in-vitro performance. These product variables in combination with patient variables, including co-ordination skill during inhaler use, intrinsic lung biology, disease and consequent pulmonary function, contribute to drug safety and efficacy outcomes. Due to the complexity of pulmonary drug delivery, predicting biological outcomes from first principles has been challenging. Ongoing research appears to offer new insights that may allow accurate prediction of drug behavior in the lungs. Disruptive innovations were characteristic of research and development in inhaled drug delivery at the end of the last century. Although there were relatively few new inhaled products launched in the first decade of the new millennium it was evident that the earlier years of exploration resulted in maturation of commercially successful technologies. A significant increase in new and generic products has occurred in the last decade and technical, regulatory and disease management trends are emerging. Some of these developments can trace their origins to earlier periods of creativity in the field while others are a reflection of advances in other areas of basic and computer, sciences and engineering. Select biological and technical advances are highlighted with reflections on the potential to impact future clinical and regulatory considerations.

Patient Inspiratory Maneuver Performance; Peak Lungpower, Acceleration and Volume

Background: Use of drug delivery devices between nebulizers, dry powder inhalers (DPIs), or metered dose inhalers (MDIs), for treating patients with asthma and chronic obstructive pulmonary disease (COPD), is based on patients' capability of coordinating the inhalation maneuver and achieving sufficient airflow. There are limited data available with regard to how patients meet the requirements of successful inhalation performance, and how the concept of inspiratory lungpower could be applied. The aim of this work was to study the patient inspiratory airflow profile performance in large data sets. We analyzed how the Kamin-Haidl inhalation criteria were met by patients with DPIs such as Easyhaler for combination therapy (EH-combi), Easyhaler for monotherapy (EH-mono), Diskus, and Turbuhaler (TH), and applied peak lungpower instead of peak inspiratory flow rate as an indicator of patient performance. Materials and Methods: Data sets gathered in two previous studies for DPIs, that is, EH-combi, EH-mono, Diskus, and TH, were used to analyze how inspiratory lungpower representing inspiratory muscle power, flow acceleration, and volume after peak met the inhalation criteria. The measured patient airflow profiles through inhalers were assessed for patients with asthma or COPD. Results: Based on the Kamin-Haidl inhalation criteria, successful inhalation requirements were met with EH-combi in 96.1% and with EH-mono in 92.6% of patients. The success rates were 89.5% and 84.6% with Diskus and TH, respectively, (p < 0.0001 between devices). In patients with asthma or COPD, the mean lungpower was 7.51 and 6.15 W for EH-combi, 8.79 and 6.88 W for EH-mono, 7.18 and 4.36 W for Diskus, and 9.65 and 6.86 W for TH, respectively, when patients followed the manufacturer's written instructions. Conclusions: Lungpower applied to the Kamin-Haidl inhalation criteria concept could be an applicable method for reviewing patient performance for different DPIs despite DPIs' characteristic differences in airflow resistance. In light of these results, DPIs provide a feasible treatment option for a large majority of respiratory patients.

Advanced design and development of nanoparticle/microparticle dual-drug combination lactose carrier-free dry powder inhalation aerosols

Rationale: lactose is the only FDA-approved carrier for dry powder inhaler (DPI) formulations in the US. Lactose carrier-based DPI products are contraindicated in patients with a known lactose allergy. Hence, inhaler formulations without lactose will benefit lactose allergic asthmatics. Objectives: to rationally design and develop lactose carrier-free dry powder inhaler formulations of fluticasone propionate and salmeterol xinafoate that will benefit people with known lactose allergy. The study also aims at improving the aerosol deposition of the dry powder formulation through advanced particle engineering design technologies to create inhalable powders consisting of nanoparticles/microparticles. Methods: advanced DPI nanoparticle/microparticle formulations were designed, developed and optimized using organic solution advanced closed-mode spray drying. The co-spray dried (co-SD) powders were comprehensively characterized in solid-state and in vitro comparative analysis of the aerodynamic performance of these molecularly mixed formulations was conducted with the marketed formulation of Advair® Diskus® interactive physical mixture. Measurements and main results: comprehensive solid-state physicochemical characterization of the powders showed that the engineered co-SD particles were small and spherical within the size range of 450 nm to 7.25 μm. Improved fine particle fraction and lower mass median aerodynamic diameter were achieved by these DPI nanoparticles/microparticles. Conclusions: this study has successfully produced a lactose-free dry powder formulation containing fluticasone propionate and salmeterol xinafoate with mannitol as excipient engineered as inhalable DPI nanoparticles/microparticles by advanced spray drying. Further, co-spray drying with mannitol and using Handihaler® device can generate higher fine particle mass of fluticasone/salmeterol. Mannitol, a mucolytic agent and aerosol performance enhancer, is a suitable excipient that can enhance aerosol dispersion of DPIs.

Novel drug delivery systems and significance in respiratory diseases

Pulmonary drug delivery offers targeted therapy for the treatment of respiratory diseases such as asthma, lung cancer, and chronic obstructive pulmonary diseases. However, this route poses challenges like deposition mechanism, drug instability, and rapid clearance mechanism. Other factors like the type of inhaler device, patient compatibility, consistent delivery by device, and inhaler technique also affect the performance of pulmonary delivery systems. Thus, to overcome these issues, pulmonary delivery systems utilizing particle-based approaches (nano/microparticles) have emerged in the last two decades. This chapter provides insight into various mechanisms of pulmonary drug administration, the ideal requirements of a pulmonary system, and the general devices used for pulmonary delivery. An overview of new pulmonary delivery systems and their relevance in the treatment of respiratory diseases is provided. In the end, novel pulmonary technologies that have been patented and cleared clinical trials have been highlighted along with the advances in the inhaler device.

Prospective evAluatIon foR inhalation devices in Greek patients with COPD and asthma: The PAIR study

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) and asthma remain a major health burden. Adherence to inhaled therapy is critical in order to optimize treatment effectiveness. Properly designed questionnaires can assess patients' satisfaction with their inhaler devices.

PATIENTS AND METHODS

A total of 766 patients with COPD, asthma or Asthma-COPD Overlap (ACO) were initially enrolled. During their first visit, patients were classified into three groups (Diskus™, Elpenhaler®, Turbuhaler®). Patients completed the FSI-10 questionnaire on Day 0 and Day 60. Test-retest reliability was evaluated.

RESULTS

A total of 705 patients completed the study. FSI-10 questionnaire had good test-retest reliability (Total Intraclass Correlation Coefficient: 0.86). All dry powder inhaler (DPIs) yielded satisfactory results. Median score of FSI-10 questionnaire in first visit (FSI-10-I) was significantly higher for patients receiving Elpenhaler® (45, 95% CI: 44 to 46) than patients receiving Diskus™ (42, 95% CI: 41 to 43) and Turbuhaler® (42, 95% CI: 41 to 43) (p < 0.001). Accordingly, median score of FSI-10 questionnaire in the final visit (FSI-10-II) was significantly higher for patients receiving Elpenhaler® (46, 95% CI: 45 to 47) than patients receiving Diskus™ (42, 95% CI: 41 to 43) and Turbuhaler® (43, 95% CI: 42 to 44) (p < 0.001).

CONCLUSION

FSI-10 questionnaire had good test-retest reliability and thus can be used in the follow-up of patients with COPD, asthma and ACO. All DPIs were highly acceptable among all study groups. Elpenhaler® achieved significantly higher ratings than Diskus™ and Turbuhaler® in FSI-10 score and presented higher preference among patients with obstructive lung diseases.

Inhaled salbutamol from aerolizer and diskus at different inhalation flows, inhalation volume and number of inhalations in both healthy subjects and COPD patients

The aim of the present study was to demonstrate the effect of inhalation-flow, inhalation-volume and number of inhalations on aerosol-delivery of inhaled-salbutamol from two different dry powder inhalers (DPIs) in both healthy-subjects and chronic obstructive pulmonary disease (COPD) patients. Relative pulmonary-bioavailability and systemic-bioavailability of inhaled-salbutamol, delivered by Diskus and Aerolizer, was determined in 24-COPD patients and 24-healthy subjects. The healthy-subjects and the COPD-patients participated in the study for 7 days in which they received 4 study doses of 200 μg salbutamol (one slow-inhalation, two slow-inhalations, one fast-inhalation, and two fast-inhalations) in four alternative days with 24 hr washout period after each dose. Two urine-samples were collected from each study subjects. The first was provided 30 min post inhalation (USAL0.5), as an index of relative pulmonary-bioavailability, and the second was pooled to 24 hr post inhalation (USAL24), as an index of systemic-bioavailability. Fast-inhalation resulted in significantly higher USAL0.5 and USAL24 than slow-inhalation (p˂0.05) after one-inhalation in both healthy-subjects and COPD-patients but there was no significant difference between slow and fast-inhalation after two-inhalations. One-inhalation resulted in significantly higher USAL0.5 and USAL24 in healthy-subjects compared to COPD-patient at both slow and fast-inhalation (p˂0.05) except USAL0.5 with Diskus at slow-inhalation there was no significant difference. Also, two-inhalations resulted in significantly higher USAL0.5 and USAL24 compared to one-inhalation at slow-inhalation only (p˂0.05). No significant difference was found between Aerolizer and Diskus except in USAL0.5 of one slow-inhalation in both health-subjects and COPD-patients (p = 0.048 and 0.047, respectively). Device-formula relation is present at low inhalation-flow since Diskus resulted in significantly higher USAL0.5 and USAL24 in healthy-subjects compared to COPD-patient at slow inhalation than Aerolizer. It is essential to inhale-twice and as hard and deep as possible from each dose when using DPI especially with COPD-patients having poor inspiratory efforts such as elderly patients and children.

Inhalation technique and asthma outcomes with different corticosteroid-containing inhaler devices

Objective: Inhaler devices must be used correctly to ensure the effectiveness of the asthma treatment. This study evaluated inhalation technique across different types of corticosteroid-containing inhaler devices as well as health outcomes in patients with asthma. Methods: In a cross-sectional study, we evaluated inhaler technique by observing patients' handling of the inhaler devices and using checklists for four inhaler types, namely Diskus (n = 52), pressure metered dose inhalers (pMDIs; n = 41), Turbuhaler (n = 36) and Twisthaler (n = 16). We also collected data on patients' characteristics, asthma therapy, exacerbations, medication adherence (8-item Morisky Medication Adherence Scale), asthma control (Asthma Control Test) and quality of life (Saint George Respiratory Questionnaire). Results: In total, we included 145 patients. The mean (SD) age of the patients was 54.5 (18.9) years and 57% were female. The majority of the patients (70%) made at least one error in their inhalation technique. Patients using Turbuhaler performed the highest number of elements correctly, followed by pMDIs, Twisthaler and Diskus. Patients with Diskus or Twisthaler had better adherence compared with patients using pMDIs or Turbuhaler. Patients using Twisthaler had better asthma outcomes than patients using the other device types. Conclusions: Most patients with asthma made mistakes when handling their inhaler devices, especially those using Diskus. However, in addition to the device type being used, patients' characteristics, asthma therapy and medication adherence also played an important role in achieving good health outcomes.

Recent advances in aerosolised drug delivery

Pulmonary route is extensively studied for the diagnosis and treatment of pulmonary and extra pulmonary disease conditions such as asthma, tuberculosis, emphysema, and bronchitis. Formulation design, inhalation device and particle size play key role in determining the aerosol performance. The lack of desired clinical outcome along with the problem regarding efficacy or any adverse drug effect may arise due to improper training and education in use of the device to control the actuation and aerosol inhalation. This review summarizes the difference in the mechanistic features of current marketed aerosol delivery devices with respect to mechanism of aerosol generation with possible advancements in the aerosol design. The delivery options in the pulmonary route and its merits together with the limitations are also discussed. An update is provided regarding the current research and clinical outcome of the use of inhalational technology.

Chronic Obstructive Pulmonary Disease in Older Adults: Part II: Considerations for Inhaler Selection

Inhaler administration for patients with chronic obstructive pulmonary disease (COPD) can be challenging, as it requires correct recall and execution of multiple steps. Older adults may have a higher risk of incorrectly administering inhalers versus the general population due to age-related visual, cognitive, and functional impairments. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2018 report states that in addition to advanced age, use of multiple inhalers and lack of previous inhaler education can negatively impact technique. Improper inhaler use can lead to poor disease control, increased acute care utilization, and reduced quality of life. Therefore, regular evaluation of technique is emphasized by the GOLD guidelines to improve patient outcomes. Health care professionals on geriatric interdisciplinary teams can work together to achieve proper technique and evaluate for age-related limitations that may guide the choice of inhalers in older adults with COPD. [Journal of Gerontological Nursing, 44(10), 10-15.].

Pharmacokinetics and pharmacodynamics of high doses of inhaled dry powder drugs

For many years, administration of drugs by inhalation has been the mainstay treatment for obstructive respiratory disorders such as asthma and chronic obstructive pulmonary disease. Antibiotics and other drugs have been administered for decades as aerosols to treat other pulmonary disease in a clinical setting, but it was until the early 1980's that colistin was formally marketed as a solution for nebulization in Europe (Colomycin, Pharmax, Bexley). The solubility of other drugs and the size of the dose required to achieve therapeutic concentrations at the site of action, made treatment times long and difficult to be performed at home. High dose dry powder delivery is a potentially effective way to deliver low potency drugs such as antibiotics. There are three major barriers to achieving the desired pharmacodynamic effect with these compounds: aerosol delivery, lung deposition and clearance. The powder formulation and device technology influence aerosol generation and may influence the size of the dose that can be achieved by inhalation in one puff. The site of deposition in the lungs is dictated by mechanisms of deposition which are influenced by the aerosol properties, particularly aerodynamic particle size distribution and the anatomy and physiology of the lungs. Finally, mechanisms of clearance dictate the local and systemic disposition of the drug, which in turn affects its pharmacokinetics and ultimately the pharmacodynamic effect and efficacy of treatment. Each of these factors will be considered and the implications for antimicrobial agent delivery as a high dose delivery example will be given.

Co-suspension delivery technology in pressurized metered-dose inhalers for multi-drug dosing in the treatment of respiratory diseases

Technologies for long-term delivery of aerosol medications in asthma and chronic obstructive pulmonary disease have improved over the past 2 decades with advancements in our understanding of the physical chemistry of aerosol formulations, device engineering, aerosol physics, and pulmonary biology. However, substantial challenges remain when a patient is required to use multiple inhaler types, multiple medications, and/or combinations of medications. Combining multiple drugs into a single inhaler while retaining appropriate dosing of the individual agents in the combination may enhance patient adherence to therapy and reduce device errors that occur when patients are using multiple inhalers. Pressurized metered-dose inhaler (pMDI) devices are widely used by patients for acute symptom relief as well as maintenance treatment, so the pMDI may be a suitable option with which to explore medication combinations. However, optimizing drug formulation remains a key challenge for pMDI delivery systems. This article introduces a new pMDI formulation approach: co-suspension delivery technology, which uses drug crystals with porous, low-density phospholipid particles engineered to deliver combinations of drugs to the airways with accurate and consistent dosing via pMDIs, independent of medication types and combinations. We describe the key characteristics of pMDIs, and discuss the rationale for the co-suspension delivery technology platform based on the limitations associated with traditional formulations. Finally, we discuss the clinical implications of co-suspension delivery technology for developing combination drug therapies administered by pMDIs.

Proposed algorithm for healthcare professionals based on product characteristics and in vitro performances in different use conditions using formoterol-based marketed products for inhalation

Healthcare professionals require an easy algorithm for selecting the most appropriate inhalation product for each patient at the beginning of a treatment. As a case study, we selected five marketed formoterol products: Foradil^® and Formagal^®, capsule-based dry powder inhalers (DPIs), Novolizer^® Formoterol and Oxis^®, reservoir-based DPIs and Formoair^®, a pressurized metered dose inhaler. We generated an algorithm based on device properties (i.e. device handling, feedback and remaining dose/end of product indication) and in vitro aerodynamic performances (i) along the product use life in optimal conditions, (ii) at different airflows and (iii) after exposing pre-loaded doses to 40°C and 75% relative humidity for 4h. Based on these results, an algorithm was built where Formoair and Formagal can be proposed when there is high risk of humidity and for patients presenting suboptimal or optimal airflows. When no risk of humidity is present, Formoair, Foradil, Formagal and Novolizer Formoterol equipped with a trigger valve could be proposed for patients presenting suboptimal airflows. When no risk of humidity is present and for patients presenting optimal airflow, all products, including Oxis, could be proposed. Ultimately, the optimal inhalation product will be selected after checking the patient's preference and capacity for correct device handling and inhalation technique.

A Randomized, Crossover Trial Evaluating Patient Handling, Preference, and Ease of Use of the Fluticasone Propionate/Formoterol Breath-Triggered Inhaler

BACKGROUND

Appropriate inhaler selection is of fundamental importance in obstructive lung disease management. Key factors in device selection include a patient's capacity to operate a particular device and their preference for it.

METHODS

This randomized, open-label, two-period, crossover study (NCT01739387) compared the ability of adolescent and adult patients with obstructive lung disease to correctly handle the fluticasone propionate/formoterol fumarate (FP/FORM; Flutiform^®) pressurized metered-dose inhaler (pMDI) and FP/FORM K-haler^®, a novel breath-triggered inhaler (BTI), following a simple, standardized training regimen. The primary endpoint was the ability to perform all steps correctly at the first attempt. Secondary endpoints included the ability to perform all critical steps correctly at the first attempt, the requisite number of attempts to successfully use the inhaler, the ability to be trained within 15 minutes, and the ability to trigger the K-haler BTI to actuate at the first attempt. Ease of device use and device preference versus patients' usual maintenance inhalers were also assessed.

RESULTS AND CONCLUSIONS

At the first attempt, an identical proportion (77.2% [95% confidence interval [CI]: 72.1, 81.8]) of 307 patients performed all pMDI and K-haler BTI handling steps correctly, whereas the corresponding proportions performing all critical steps correctly were 82.4% (95% CIs: 77.7, 86.5) and 87.0% (95% CI: 82.7, 90.5), respectively. For both devices, >90% of patients required only two attempts to master device usage; >99% of patients could be trained to correctly use each device within 15 minutes. Virtually all patients (99.0% [95% CIs: 97.2, 99.8]) were able to successfully trigger the K-haler BTI's dose-release mechanism at first attempt. Ease of use and preference data for FP/FORM pMDI challenged the perceived wisdom that dry powder inhalers are necessarily simpler to use, whereas the corresponding data for FP/FORM K-haler strongly favored this novel BTI over the Turbuhaler^®, Accuhaler^®, and other pMDIs.

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.

Inhalation device requirements for patients' inhalation maneuvers

BACKGROUND

Inhaled drugs are the mainstay of treatment for lung diseases such as asthma and chronic obstructive pulmonary disease. However, failure to use inhalation devices correctly can lead to a poorly controlled status. A vast number of inhalation devices exist and each device has specific requirements to achieve optimum inhalation of the drug. Currently, there is no overview of inhalation requirements considering all devices. This article presents a review of the literature on different inhalation device requirements and incorporates the data into a new inhalation flow algorithm.

METHODS

Data from literature on commercially available inhalation devices were evaluated and parameters, such as inhalation flow rate, flow acceleration, inhalation volume, and inspiration time assessed for the required inhalation maneuver specific to the device. All agreed upon data points were used to develop an inhalation flow algorithm.

RESULTS

The literature analysis revealed availability of robust data for the required inhalation flow characteristics for most devices and thus for the development of an algorithm. For those devices for which these parameters are not published, the minimum required flow criteria were defined based on published data regarding individual aspects of aerosol quality.

CONCLUSIONS

This review provides an overview of inhalation devices available on the market regarding requirements for an acceptable inhalation maneuver and shows which goals should be achieved in terms of inhalation flows. The presented algorithm can be used to develop a new computer based measurement system which could help to test and train patients' individual inhalation maneuvers with their inhalation devices.

The economic burden of asthma and chronic obstructive pulmonary disease and the impact of poor inhalation technique with commonly prescribed dry powder inhalers in three European countries

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) are common chronic inflammatory respiratory diseases, which impose a substantial burden on healthcare systems and society. Fixed-dose combinations (FDCs) of inhaled corticosteroids (ICS) and long-acting β2 agonists (LABA), often administered using dry powder inhalers (DPIs), are frequently prescribed to control persistent asthma and COPD. Use of DPIs has been associated with poor inhalation technique, which can lead to increased healthcare resource use and costs.

METHODS

A model was developed to estimate the healthcare resource use and costs associated with asthma and COPD management in people using commonly prescribed DPIs (budesonide + formoterol Turbuhaler(®) or fluticasone + salmeterol Accuhaler(®)) over 1 year in Spain, Sweden and the United Kingdom (UK). The model considered direct costs (inhaler acquisition costs and scheduled and unscheduled healthcare costs), indirect costs (productive days lost), and estimated the contribution of poor inhalation technique to the burden of illness.

RESULTS

The direct cost burden of managing asthma and COPD for people using budesonide + formoterol Turbuhaler(®) or fluticasone + salmeterol Accuhaler(®) in 2015 was estimated at €813 million, €560 million, and €774 million for Spain, Sweden and the UK, respectively. Poor inhalation technique comprised 2.2-7.7 % of direct costs, totalling €105 million across the three countries. When lost productivity costs were included, total expenditure increased to €1.4 billion, €1.7 billion and €3.3 billion in Spain, Sweden and the UK, respectively, with €782 million attributable to poor inhalation technique across the three countries. Sensitivity analyses showed that the model results were most sensitive to changes in the proportion of patients prescribed ICS and LABA FDCs, and least sensitive to differences in the number of antimicrobials and oral corticosteroids prescribed.

CONCLUSIONS

The cost of managing asthma and COPD using commonly prescribed DPIs is considerable. A substantial, and avoidable, contributor to this burden is poor inhalation technique. Measures that can improve inhalation technique with current DPIs, such as easier-to-use inhalers or better patient training, could offer benefits to patients and healthcare providers through improving disease outcomes and lowering costs.

Inhalation devices: from basic science to practical use, innovative vs generic products

INTRODUCTION

Inhalation therapy is a convenient method of treating respiratory diseases. The key factors required for inhalation are the preparation of drug carriers (aerosol particles) allowing reproducible dosing during administration. These technical challenges are accomplished with a variety of inhalation devices (inhalers) and medicinal formulations, which are optimized to be easily converted into inhalable aerosols. Areas covered: This review is focused on the most important, but often overlooked, effects, which are required for the reliable and reproducible inhalable drug administration. The effects of patient-related issues that influence inhalation therapy, such as proper selection of inhalers for specific cases is discussed. We also discuss factors that are the most essential if generic inhalation product should be considered equivalent to the drugs with the clinically confirmed efficacy. Expert opinion: Proper device selection is crucial in clinical results of inhalation therapy. The patients' ability to coordinate inhalation with actuation, generation of optimal flow through the device, use of optimal inspiratory volume, all produces crucial effects on disease control. Also the severity of the disease process effects proper use of inhalers. Interchanging of inhalers can produce potentially conflicting problem regarding efficacy and safety of inhalation therapy.

Evaluation of dry powder inhalers with a focus on ease of use and user preference in inhaler-naïve individuals

Inhaler errors are common amongst inhaler users. Therefore, in the development work of new inhalation devices, it is important to characterize the ease of use of the inhalers. In this study four dry powder inhalers, Diskus, Easyhaler, Ellipta and Turbuhaler, were evaluated, focusing on ease of use and patient preference. The study used a triangular methodology. The sample consisted of 31 inhaler naïve individuals. Educational videos for all inhalers were watched, and afterwards, the use of all four inhalers was demonstrated in a random order. The demonstrations were videotaped. Thereafter they were checked against a predefined checklist and all mistakes were recorded. Only 33% of inhaler demonstrations were completed without the participants making any mistakes. The proportions of subjects who used the devices correctly were as follows: Diskus 48%, Easyhaler 19%, Ellipta 55% and Turbuhaler 16%. When comparing correct and incorrect inhaler technique for each inhaler pair the following differences were statistically significant: Diskus vs. Easyhaler (p<0.05), Ellipta vs. Easyhaler (p<0.01), Diskus vs. Turbuhaler (p<0.01), Ellipta vs. Turbuhaler (p<0.01). In the participants' ranking, the inhalers Ellipta, followed by Turbuhaler, were most often ranked as most preferred. Participants' preference of Ellipta over Easyhaler (p<0.01) and over Diskus (p<0.001) were statistically significant.

Evaluation of inhaler handling-errors, inhaler perception and preference with Spiromax, Easyhaler and Turbuhaler devices among healthy Finnish volunteers: a single site, single visit crossover study (Finhaler)

Introduction

Correct inhaler technique and device preference are positively correlated with improved adherence and clinical outcomes. This study was designed to investigate inhaler technique mastery and device preference for three different dry powder inhalers, Spiromax, Easyhaler and Turbuhaler.

Methods

This was a single site, single visit, crossover study assessing device mastery, handling errors and preference using empty Spiromax, Easyhaler and Turbuhaler devices in healthy adult Finnish volunteers. Inhaler naïve adult participants were observed by healthcare professionals (HCPs) to evaluate the proportion of participants achieving device mastery (defined as an absence of HCP observed errors) using a three-step approach: (1) intuitive use (with no instructions), (2) after reading the patient information leaflet and (3) after HCP instruction. HCPs monitored and recorded errors based on device-specific handling error checklists. At the end of the study, participants completed a device preference questionnaire and rated their satisfaction with the three devices.

Results

Spiromax was correctly used by 37.5% and 93.3% of participants in steps 1 and 2, respectively, compared with 0% and 58.3% with Easyhaler, and 9.2% and 76.7% with Turbuhaler. All three devices showed high mastery (>95%) in step 3. The most common error reported with Spiromax was related to the orientation of the device. Not shaking the device was the most common error with Easyhaler. Errors in priming the device were the most common with Turbuhaler. Spiromax, Easyhaler and Turbuhaler were rated as the ‘easiest device to use’ by 73.1%, 12.6% and 14.3% of participants, respectively. The HCP instructions clearly improved the use of all devices.

Conclusion

Higher levels of device mastery, including intuitive/ease of use, were reported by naïve users when using Spiromax compared with Easyhaler and Turbuhaler.

Characteristics of patients making serious inhaler errors with a dry powder inhaler and association with asthma-related events in a primary care setting

OBJECTIVE

Correct inhaler technique is central to effective delivery of asthma therapy. The study aim was to identify factors associated with serious inhaler technique errors and their prevalence among primary care patients with asthma using the Diskus dry powder inhaler (DPI).

METHODS

This was a historical, multinational, cross-sectional study (2011-2013) using the iHARP database, an international initiative that includes patient- and healthcare provider-reported questionnaires from eight countries. Patients with asthma were observed for serious inhaler errors by trained healthcare providers as predefined by the iHARP steering committee. Multivariable logistic regression, stepwise reduced, was used to identify clinical characteristics and asthma-related outcomes associated with ≥1 serious errors.

RESULTS

Of 3681 patients with asthma, 623 (17%) were using a Diskus (mean [SD] age, 51 [14]; 61% women). A total of 341 (55%) patients made ≥1 serious errors. The most common errors were the failure to exhale before inhalation, insufficient breath-hold at the end of inhalation, and inhalation that was not forceful from the start. Factors significantly associated with ≥1 serious errors included asthma-related hospitalization the previous year (odds ratio [OR] 2.07; 95% confidence interval [CI], 1.26-3.40); obesity (OR 1.75; 1.17-2.63); poor asthma control the previous 4 weeks (OR 1.57; 1.04-2.36); female sex (OR 1.51; 1.08-2.10); and no inhaler technique review during the previous year (OR 1.45; 1.04-2.02).

CONCLUSIONS

Patients with evidence of poor asthma control should be targeted for a review of their inhaler technique even when using a device thought to have a low error rate.

The ELLIPTA® Dry Powder Inhaler: Design, Functionality, In Vitro Dosing Performance and Critical Task Compliance by Patients and Caregivers

Dry powder inhalers (DPIs) are commonly used for the delivery of inhaled medications, and should provide consistent, efficient dosing, be easy to use correctly, and be liked by patients; these attributes can all affect patient compliance and therefore treatment efficacy. The ELLIPTA^® DPI was developed for the delivery of once-daily therapies for the treatment of asthma and chronic obstructive pulmonary disease. It has moderate resistance to airflow and can hold one or two blister strips, with each blister containing a sealed single dose of medication. Monotherapies can be delivered by the single-strip configuration and, in the two-strip configuration, one dose from each strip can be aerosolized simultaneously to allow combination therapies to be delivered, which enables the formulations for each product to be developed individually, since they are stored separately until the point of administration. There are three principal operating steps to administer a dose: open, inhale, close. This article summarizes the design, functionality, and in vitro dose-delivery characteristics of the ELLIPTA inhaler, and describes the results of human factors validation tests, designed to assess the performance of critical tasks required to use the inhaler. Results from the in vitro studies indicate that the ELLIPTA inhaler performs consistently with respect to in vitro dose delivery characteristics at a range of flow rates that can be achieved by the target population (≥30 L/min) and over its 30-day in-use life. Data from the human factors validation tests demonstrated that almost all participants (≥97%) were able to complete each of the steps required to prepare a dose for inhalation without error. Overall, the ELLIPTA inhaler has a versatile single- or two-strip design that allows it to be used for the delivery of a range of treatment options. It also improves patient ease-of-use when compared with the DISKUS^® DPI.

Effect of Flow Rate on In Vitro Aerodynamic Performance of NEXThaler(®) in Comparison with Diskus(®) and Turbohaler(®) Dry Powder Inhalers

Background: European and United States Pharmacopoeia compendial procedures for assessing the in vitro emitted dose and aerodynamic size distribution of a dry powder inhaler require that 4.0 L of air at a pressure drop of 4 kPa be drawn through the inhaler. However, the product performance should be investigated using conditions more representative of what is achievable by the patient population. This work compares the delivered dose and the drug deposition profile at different flow rates (30, 40, 60, and 90 L/min) of Foster NEXThaler^® (beclomethasone dipropionate/formoterol fumarate), Seretide^® Diskus^® (fluticasone propionate/salmeterol xinafoate), and Symbicort^® Turbohaler^® (budesonide/formoterol fumarate).

Methods: The delivered dose uniformity was tested using a dose unit sampling apparatus (DUSA) at inhalation volumes either 2.0 or 4.0 L and flow rates 30, 40, 60, or 90 L/min. The aerodynamic assessment was carried out using a Next Generation Impactor by discharging each inhaler at 30, 40, 60, or 90 L/min for a time sufficient to obtain an air volume of 4 L.

Results: Foster^® NEXThaler^® and Seretide^® Diskus^® showed a consistent dose delivery for both the drugs included in the formulation, independently of the applied flow rate. Contrary, Symbicort^® Turbohaler^® showed a high decrease of the emitted dose for both budesonide and formoterol fumarate when the device was operated at airflow rate lower that 60 L/min. The aerosolizing performance of NEXThaler^® and Diskus^® was unaffected by the flow rate applied. Turbohaler^® proved to be the inhaler most sensitive to changes in flow rate in terms of fine particle fraction (FPF) for both components. Among the combinations tested, Foster NEXThaler^® was the only one capable to deliver around 50% of extra-fine particles relative to delivered dose.

Conclusions: NEXThaler^® and Diskus^® were substantially unaffected by flow rate through the inhaler in terms of both delivered dose and fine particle mass.

Effect of Device Design and Formulation on the In Vitro Comparability for Multi-Unit Dose Dry Powder Inhalers

The focus of this investigation was to understand the design space to achieve comparable in vitro performance of two multi-unit dose dry powder inhalers (DPIs)—Flixotide® Accuhaler® (reference product) and MultiHaler® (test product). Flow field, pressure drop and particle trajectories within the test and reference DPI devices were modelled via computational fluid dynamics (CFD). Micronized fluticasone propionate (FP) was characterized to determine particle size distribution (PSD), specific surface area (SSA) and surface interfacial properties using cohesive-adhesive balance (CAB). CFD simulations suggested that the pressure drop and airflow velocity in the MultiHaler® were greater than Accuhaler®. Two modified test devices (MOD MH 1 and MOD MH 2) were manufactured with the introduction of by-pass channels in the airflow path, which achieved comparable specific resistance and airflow path between the test and reference devices. Assessment of reference product formulation in modified test devices suggested that MOD MH 2 achieved comparable in vitro performance to the reference product. CAB analysis suggested that adhesion of all FP batches to lactose was different, with batch D showing greatest and batch A least adhesion to lactose. Test DPI formulations were manufactured using four different batches of FP with milled or sieved lactose, and showed that batch A FP formulated with sieved lactose in MOD MH 2 device demonstrated the highest degree of similarity to the Accuhaler® in vitro deposition. Application of CFD modelling and material characterization of formulation raw materials enabled the modification of device and formulation critical material attributes to create an in vitro comparable device/formulation system to the reference product.

Identifying the features of an easy-to-use and intuitive dry powder inhaler for asthma and chronic obstructive pulmonary disease therapy: results from a 28-day device handling study, and an airflow resistance study

BACKGROUND

Many patients with asthma and chronic obstructive pulmonary disease (COPD) symptoms remain insufficiently controlled despite inhalation treatment, with poor inhaler technique recognized as a significant contributor. Dry powder inhalers (DPIs) need less coordination of actuation and inspiration than pressured metered dose inhalers.

OBJECTIVES

To assess whether consideration of 'ideal inhaler' features during design and development of a new DPI device (Forspiro® Sandoz AG, Switzerland) led to an easy-to-use and reliable inhaler.

METHODS

Two studies are reported here: i) 24 adult Accuhaler® users received either limited written instructions (n = 12) or fully illustrated instructions (n = 12) for the Forspiro device; and ii) peak inspiratory flow rates through the Forspiro device were assessed in 30 adult and 10 pediatric patients with asthma and 10 adult patients with COPD.

RESULTS

All subjects understood the correct sequence of actions for the Forspiro device and rated all aspects of handling the device as 'very easy' or 'fairly easy' (except one uninstructed subject who rated 'ease of determining number of doses left' as 'fairly difficult'). All patients achieved ≥ 35 l/min, thus demonstrating that the Forspiro device provides low-medium airflow resistance.

CONCLUSIONS

Inhaler design providing good drug delivery with maximum ease of use may lead to more reliable therapy and improved control of airway diseases.

Technological and practical challenges of dry powder inhalers and formulations

In the 50 years following the introduction of the first dry powder inhaler to the market, several developments have occurred. Multiple-unit dose and multi-dose devices have been introduced, but first generation capsule inhalers are still widely used for new formulations. Many new particle engineering techniques have been developed and considerable effort has been put in understanding the mechanisms that control particle interaction and powder dispersion during inhalation. Yet, several misconceptions about optimal inhaler performance manage to survive in modern literature. It is, for example still widely believed that a flow rate independent fine particle fraction contributes to an inhalation performance independent therapy, that dry powder inhalers perform best at 4 kPa (or 60 L/min) and that a high resistance device cannot be operated correctly by patients with reduced lung function. Nevertheless, there seems to be a great future for dry powder inhalation. Many new areas of interest for dry powder inhalation are explored and with the assistance of new techniques like computational fluid dynamics and emerging particle engineering technologies, this is likely to result in a new generation of inhaler devices and formulations, that will enable the introduction of new therapies based on inhaled medicines.

The acoustic features of inhalation can be used to quantify aerosol delivery from a Diskus™ dry powder inhaler

PURPOSE

Some patients are unable to generate the peak inspiratory flow rate (PIFR) necessary to de-agglomerate drug particles from dry powder inhalers (DPIs). In this study we tested the hypothesis that the acoustic parameters of an inhalation are related to the PIFR and hence reflect drug delivery.

METHODS

A sensitivity analysis of the relationship of the acoustics of inhalation to simultaneously recorded airflow, in a cohort of volunteers (n = 92) was performed. The Next Generation Impactor (NGI) was used to assess in vitro drug delivery from salmeterol/fluticasone and salbutamol Diskus™ DPIs. Fine particle fraction, FPF, (<5 μm) was measured at 30-90 l/min for 2-6 s and correlated with acoustically determined flow rate (IFRc). In pharmacokinetic studies using a salbutamol (200 μg) Diskus™, volunteers inhaled either at maximal or minimal effort on separate days.

RESULTS

PIFRc was correlated with spirometrically determined values (R (2) = 0.88). In in vitro studies, FPF increased as both flow rate and inhalation duration increased for the salmeterol/fluticasone Diskus™ (Adjusted R (2) = 0.95) and was proportional to flow rate only for the salbutamol Diskus™ (Adjusted R (2) = 0.71). In pharmacokinetic studies, blood salbutamol levels measured at 20 min were significantly lower when PIFRc was less than 60 l/min, p < 0.0001.

CONCLUSION

Acoustically-determined PIFR is a suitable method for estimating drug delivery and for monitoring inhalation technique over time.

Comparing usability of NEXThaler(®) with other inhaled corticosteroid/long-acting β2-agonist fixed combination dry powder inhalers in asthma patients

BACKGROUND

Inhaler mishandling is a common issue among patients suffering from asthma and is associated with poor clinical outcomes and greater consumption of health-care resources. Ease of use can improve inhaler technique and, possibly, patients' preference for their inhaler device, which in turn may lead to better adherence to therapy.

METHODS

This study investigated usability characteristics of NEXThaler(®) versus two other dry powder inhalers (DPIs; Diskus(®) and Turbuhaler(®)). Sixty-six adult patients with asthma (mean age 42.9±17.7 years) and with no previous experience of using a DPI were included in a randomized crossover comparison of the three devices. The main measures of usability were the number of steps failed for each device and the number of people who were able to use the device successfully (effectiveness), the time it took patients to set up the device and the time to read the instructions for use (IFU; efficiency), and patient preferences (satisfaction). Inhaler technique was evaluated after the IFU leaflet was read.

RESULTS

NEXThaler was found to be superior to the other two DPIs in terms of the number of device use failures (p<0.001), time to set up (p<0.001), and time to read IFU (p<0.001). Additionally, the proportion of participants who completed a successful inhalation without any errors at all was significantly higher for NEXThaler than for Diskus and Turbuhaler (p<0.001). Patients rated NEXThaler as the easiest to use and most preferred inhaler to own (p<0.001).

CONCLUSIONS

NEXThaler displayed better usability compared with Diskus and Turbuhaler. The improved usability and higher satisfaction with the device may contribute to increased patient adherence to asthma treatment.

Inhaled corticosteroid and long-acting β2-agonist pharmacological profiles: effective asthma therapy in practice

Fixed-dose combinations of inhaled corticosteroids (ICSs) and long-acting β2-agonists (LABAs) have been used to manage asthma for several years. They are the preferred therapy option for patients who do not achieve optimal control of their asthma with low-dose ICS monotherapy. In Europe, four ICS/LABA products are commercially available for asthma maintenance therapy (fluticasone propionate/formoterol fumarate, fluticasone propionate/salmeterol xinafoate, budesonide/formoterol fumarate and beclometasone dipropionate/formoterol fumarate), and other combinations are likely to be developed over the next few years (e.g. mometasone/formoterol fumarate, fluticasone furoate/vilanterol, mometasone/indacaterol). Data from randomized, controlled, clinical trials do not demonstrate a clear overall efficacy difference among ICS/LABA combinations approved for asthma therapy. Conversely, pharmacological data indicate that there may be certain advantages to using one ICS or LABA over another because of the specific pharmacodynamic and pharmacokinetic profiles associated with particular treatments. This review article summarizes the pharmacological characteristics oft he various ICSs and LABAs available for the treatment of asthma, including the potential for ICS and LABA synergy, and gives an insight into the rationale for the development of the latest ICS/LABA combination approved for asthma maintenance therapy.

Dose emission characteristics of placebo PulmoSphere® particles are unaffected by a subject's inhalation maneuver

BACKGROUND

Good compliance to the prescribed dosing regimen and inhaler instructions for use are critical for asthma/chronic obstructive pulmonary disease (COPD) patients to achieve good control of their disease. We investigated the extent to which a system comprising porous particles delivered with a passive dry powder inhaler could be designed to achieve significant reductions in dose inhalation errors.

METHODS

Porous placebo particles were prepared by an emulsion-based spray-drying method (PulmoSphere® technology). The formulations were administered as dry powders with a portable, blister-based dry powder inhaler (Simoon Inhaler). The inhalation profiles of 69 asthma/COPD subjects were determined with an inhaler simulator with resistance comparable to that of the Simoon Inhaler. Powder emptying from the device was assessed by laser photometry. Aerosol performance was assessed on a Next Generation Impactor, and with the idealized Alberta mouth-throat model using both square-wave and subject-inhalation profiles generated in the breathing study.

RESULTS

Virtually all subjects could achieve a pressure drop of at least 1 kPa and an inhaled volume of at least 500 mL with the Simoon Inhaler. In vitro measures of particle deposition were found to be largely independent of the inhalation maneuver (flow rate, inhaled volume, ramp time) across the broad range of inhalation profiles observed in the breathing study. The rapid emptying of powder from the Simoon Inhaler minimizes the impact of dose-related errors, such as failure to exhale before inhalation and failure to breath-hold post inhalation.

CONCLUSIONS

Inertial impaction that is largely independent of a subject's inhalation maneuver can be achieved with a drug/device combination product comprising a porous particle formulation and blister-based inhaler.

[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.