Effect of inhalation profile and throat geometry on predicted lung deposition of budesonide and formoterol (BF) in COPD: An in-vitro comparison of Spiromax with Turbuhaler

The effect of exhalation before the inhalation of dry powder aerosol drugs on the breathing parameters, emitted doses and aerosol size distributions

Airway deposition of aerosol drugs is highly dependent on the breathing manoeuvre of the patients. Though incorrect exhalation before the inhalation of the drug is one of the most common mistakes, its effect on the rest of the manoeuvre and on the airway deposition distribution of aerosol drugs is not explored in the open literature. The aim of the present work was to conduct inhalation experiments using six dry powder inhalers in order to quantify the effect of the degree of lung emptying on the inhalation time, inhaled volume and peak inhalation flow. Another goal of the research was to determine the effect of the exhalation on the aerodynamic properties of the drugs emitted by the same inhalers. According to the measurements, deep exhalation before drug inhalation increased the volume of the inhaled air and the average and maximum values of the inhalation flow rate, but the extent of the increase was patient and inhaler specific. For different inhalers, the mean value of the relative increase in peak inhalation flow due to forceful exhalation was between 15.3 and 38.4% (min: Easyhaler®, max: Breezhaler®), compared to the case of normal (tidal) exhalation before the drug inhalation. The relative increase in the inhaled volume was between 36.4 and 57.1% (min: NEXThaler®, max: Turbuhaler®). By the same token, forceful exhalation resulted in higher emitted doses and smaller emitted particles, depending on the individual breathing ability of the patient, the inhalation device and the drug metered in it. The relative increase in the emitted dose varied between 0.2 and 8.0% (min: Foster® NEXThaler®, max: Bufomix® Easyhaler®), while the relative enhancement of fine particle dose ranged between 1.9 and 30.8% (min: Foster® NEXThaler®, max: Symbicort® Turbuhaler®), depending on the inhaler. All these effects and parameter values point toward higher airway doses due to forceful exhalation before the inhalation of the drug. At the same time, the present findings highlight the necessity of proper patient education on the importance of lung emptying, but also the importance of patient-specific inhaler-drug pair choice in the future.

Characterization of dry powder inhaler performance through experimental methods

Experimental methods provide means for the quality control of existing DPIs and for exploring the influence of formulation and device parameters well in advance of clinical trials for novel devices and formulations. In this review, we examine the state of the art of in vitro testing of DPIs, with a focus primarily on the development of accurate in vitro-in vivo correlations. Aspects of compendial testing are discussed, followed by the influence of flow profiles on DPI performance, the characterization of extrathoracic deposition using mouth-throat geometries, and the characterization of regional thoracic deposition. Additional experimental methods that can inform the timing of bolus delivery, the influence of environmental conditions, and the development of electrostatic charge on aerosolized DPI powders are reviewed. We conclude with perspectives on current in vitro methods and identify potential areas for future investigation, including the estimation of variability in deposition, better characterization of existing compendial methods, optimization of formulation and device design to bypass extrathoracic deposition, and the use of novel tracheobronchial filters that aim to provide more clinically relevant measures of performance directly from in vitro testing.

Narrative Review of the Role of Patient-Reported Outcomes and Inhaler Handling Errors in the Control of Asthma and COPD

Purpose of Review

Asthma and chronic obstructive pulmonary disease (COPD) are chronic respiratory diseases that remain uncontrolled in many patients, despite the wide range of therapeutic options available. This review analyzes the available clinical evidence on 3 budesonide/formoterol DPI devices, Spiromax^®, Turbuhaler^®, and Easyhaler^®, in terms of patient-reported outcomes (PROs), inhaler errors, and asthma and COPD control.

Recent Findings

The effectiveness of dry powder inhalers (DPI) depends largely on the device and the patient’s inhaler technique. Equally important are the patient’s perception of the inhaler and adherence. Given the high burden of these diseases, it is important that efforts be made to select the best DPI for each patient and to analyze the impact of these variables to help improve the health and quality of life of our patients.

Summary

This review provides a comprehensive overview of the present knowledge about PROs, inhaler handling errors, and asthma and COPD control achieved by Spiromax^®, Turbuhaler^®, and Easyhaler^®.

In Vitro Performance of the Wixela Inhub Inhaler Using Severe Chronic Obstructive Pulmonary Disease Patient Inhalation Profiles

Background: Wixela Inhub (trademarks of Viatris, Inc.) is a dry powder inhaler (DPI) that delivers a fixed-dose combination of fluticasone propionate and salmeterol and is approved as a generic equivalent to Advair Diskus (trademarks of GlaxoSmithKline plc) for the treatment of asthma and chronic obstructive pulmonary disease (COPD). The dosing performance of DPIs is dependent on the patient's inspiratory capability, which may be impacted in disease populations such as those with severe COPD. The objective of this study was to evaluate the in vitro dose delivery of fluticasone propionate and salmeterol from the Inhub inhaler with in vivo inhalation profiles of severe COPD patients, using two types of breathing simulator with different modes of operation. Materials and Methods: Two breathing simulators (Si-Plan and Copley BRS3100) were used with United States Pharmacopoeia (USP) <601> apparatus 5 (Next Generation Impactor and accessories) to measure the total emitted dose and fine particle mass of fluticasone propionate and salmeterol for Wixela Inhub (250/50 mcg) using 13 severe COPD patient inhalation profiles. Results: Wixela Inhub demonstrated low flow dependency across the range of COPD patient profiles tested (peak inspiratory flow rate 60.8-84.9 L minute^-1), when assessed by total emitted dose and fine particle mass. The results were similar to literature results reported for fluticasone propionate from the Diskus inhaler, tested using a proprietary breathing simulator and Andersen Cascade Impactor. Comparison between the breathing simulators showed no significant difference in fluticasone propionate results, but a small difference was observed between the breathing simulators for salmeterol total emitted dose and fine particle mass. Conclusions: This study demonstrates that severe COPD patients are likely to achieve a consistent inhaled dose from Wixela Inhub, with low flow dependency observed within this patient population. In addition, both breathing simulators, which differ significantly in design, produced similar results for fluticasone propionate, but yielded slightly (but statistically significant) different results for salmeterol.

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.

Modeling of Inhalation Profiles Through Dry Powder Inhaler in Healthy Adults and Asthma Patients As a Prerequisite for Further In Vitro and In Silico Studies

Background: The severity of airway obstruction may affect patient's ability to perform an effective drug inhalation from a dry powder inhaler (DPI). Also, an incorrect inhalation technique may negatively affect the efficacy of asthma treatment. The aims of the study were (1) to analyze and compare inhalation profiles recorded with the use of different inhalation techniques, and thus, (2) to establish model inhalation profiles representative for healthy subjects and subjects with mild and moderate-to-severe asthma. Methods: This study was performed in healthy volunteers, patients with mild and moderate-to-severe asthma. A modified flow-volume test to define two different expiratory levels (to residual volume and half-way to residual volume) was performed. Inspiratory flow parameters were extracted: peak inspiratory flow rate (PIF_inh), time at which peak inspiratory flow rate occurs (tPIF_inh), total inhalation time (T), and inhaled volume (V). Test of frequency for tPIF_inh100% and tPIF_inh50% by asthma severity was performed, to provide information about initial flow accelerations. The impact of two different expiratory levels preceding inhalation (with severity of asthma as a categorical factor) on inspiratory flow parameters was examined. Results: PIF_inh was dependent upon asthma severity (p = 0.046). Type of exhalation before inhalation had no effect on PIF_inh values. V value was significantly affected both by asthma severity (p = 0.024) and type of exhalation before inhalation (p < 0.0001). Mean T value was influenced by type of exhalation before inhalation (p = 0.0003), but not by asthma severity. Mean tPIF_inh value was affected by the type of exhalation before inhalation only in healthy subjects (p = 0.01). Conclusions: Both asthma severity and type of exhalation before inhalation have little impact on the dynamics of inhalation through a DPI. An alternative form of equation describing inhalation profiles demonstrating a relationship between lung mechanics and dynamics of inspiratory profile has been proposed.

Using Filters to Estimate Regional Lung Deposition with Dry Powder Inhalers

PURPOSE

To develop an in vitro method to rapidly evaluate regional lung doses delivered by pharmaceutical inhalers. Currently, cascade impactor measurements are used, but these are resource intensive and require significant post processing of in vitro data to arrive at regional deposition estimates.

METHODS

We present a specialized filter apparatus that mimics tracheobronchial (TB) deposition of pharmaceutical aerosols emitted by commercially available dry powder inhalers (DPIs). The filter housing includes an electrostatic neutralizer to eliminate artificial electrostatic filtration effects. Regional deposition (tracheobronchial and alveolar) for four DPIs (Onbrez Breezhaler, Flovent Diskus, Pulmicort Turbuhaler, and Asmanex Twisthaler) was estimated using cascade impactor measurements and an in silico regional deposition model. These estimates were compared to direct measurements of regional deposition as provided by the TB filter mimic and an absolute filter placed downstream of the TB filter housing, representing the alveolar dose.

RESULTS

The two methods were shown to provide similar estimates of extrathoracic, tracheobronchial, and alveolar deposition, as well as total recovery of active pharmaceutical ingredients.

CONCLUSIONS

Because of its design, the TB filter apparatus makes it possible to estimate regional deposition with inhalers directly using variable inhalation profiles without any additional equipment or changes to the experimental configuration. This method may be useful to expedite development of both innovative and generic drug products as it provides regional respiratory tract deposition estimates using fewer resources than exisiting methods.

Inhalation Profiles Through a Dry Powder Inhaler: Relation Between Inhalation Technique and Spirometric Measures

Background: The understanding of the real flow profiles through a dry powder inhaler (DPI), generated by asthma patients, is a prerequisite for satisfactory drug delivery to the lungs. The aims of the study were to assess the relationship between spirometric measures and inhalation profiles through a low-resistance DPI, and to compare parameters of those profiles between optimal and suboptimal inhalation technique type. Methods: Both healthy adult volunteers and patients with asthma were included in the study. Spirometry was conducted along with modified flow-volume test to detect expiratory levels (maximum "100%" exhalation to residual volume [RV] and halfway "50%" to RV). These were the reference levels of the depth of exhalation for each patient to simulate the effect of incomplete exhalation. Individual inhalation profiles were recorded using spirometry in-house software as the volumetric airflow through the inhaler versus time. Inspiratory flow parameters were extracted: time to peak inspiratory flow through inhaler (PIF_inh), time at which peak inspiratory flow occurs (tPIF_inh), total inhalation time (T), and inhaled volume during maneuver (V). Results and Conclusions: There are significant relationships between spirometric indices and parameters of inhalation through a low-resistance, cyclohaler-type DPI (assessed by single-factor analysis of Spearman's rank correlation coefficient). Multiple regression models were constructed, predicting inspiratory flow parameters (including spirometric indices, demographic parameters, and inhaler's usage history as determinants). The exhalation halfway to RV before inhalation did not affect significantly PIF_inh and tPIF_inh (and, thus, initial flow dynamics) in asthma patients. T and V parameters were then significantly decreased, but seemed sufficient for successful DPI performance. Both exhalation to RV and incomplete exhalation halfway to RV preceding inhalation allow for effective usage of low-resistance DPI.

In Vitro Effect of Different Airflow Rates on the Aerosol Properties of Nebulized Glycopyrrolate in the eFlow® Closed System and Tiotropium Delivered in the HandiHaler®

INTRODUCTION

Personalized therapy for patients with COPD requires appropriate choice of drug and delivery device. Inhalers and nebulizers vary in their drug delivery characteristics, particularly the need for passive or active patient inhalation for appropriate drug dispersal and delivery. In this in vitro analysis, we assessed the aerosol performance and drug delivery of two long-acting muscarinic antagonists, glycopyrrolate (GLY; 25 µg solution; 1 ml) and tiotropium (TIO; 18 µg powder) through their respective delivery systems: the eFlow® Closed System (CS) vibrating membrane nebulizer and the HandiHaler® dry-powder inhaler (DPI).

METHODS

The aerosol performances of the eFlow® CS nebulizer and the HandiHaler® were determined using the Next Generation cascade Impactor. The delivered dose of GLY and TIO was determined using different breathing patterns, which varied in tidal volume and peak inspiratory flow rate, respectively, to simulate breathing conditions ranging from normal to severe obstruction.

RESULTS

Aerodynamic particle analysis showed generally similar mass median aerodynamic diameter (MMAD, range, 3.6-4.6 µm) and fine particle fraction (FPF, range, 48.2%-63.7%) with GLY delivered using the eFlow® CS nebulizer under all breathing patterns tested. TIO, delivered via the HandiHaler®, showed variations in MMAD (range, 3.8-5.8 µm) and FPF (range, 16.1%-32.4%) under different inspiratory flow rates. The majority of GLY was deposited in stages 2-5 of the impactor, which corresponds with particle sizes in the respirable range (< 5 µm), whereas a large proportion of TIO was deposited in the throat/mouthpiece pre-separator, irrespective of test conditions. The median residual dose of GLY with eFlow® CS was notably lower compared to that of TIO with HandiHaler® (2.4%-4.4% vs. 40%-67%, respectively).

CONCLUSIONS

These simulation results highlight the different deposition patterns generated by a DPI device and a vibrating membrane nebulizer, which may help inform device selection and treatment decision in COPD management.

In vitro-in vivo correlations (IVIVCs) of deposition for drugs given by oral inhalation

Conventional in vitro tests to assess the aerodynamic particle size distribution (APSD) from inhaler devices use simple right-angle inlets ("mouth-throats", MTs) to cascade impactors, and air is drawn through the system at a fixed flow for a fixed time. Since this arrangement differs substantially from both human oropharyngeal airway anatomy and the patterns of air flow when patients use inhalers, the ability of in vitro tests to predict in vivo deposition of pharmaceutical aerosols has been limited. MTs that mimic the human anatomy, coupled with simulated breathing patterns, have yielded estimates of lung dose from in vitro data that closely match those from in vivo gamma scintigraphic or pharmacokinetic studies. However, different models of MTs do not always yield identical data, and selection of an anatomical MT and representative inhalation profiles remains challenging. Improved in vitro - in vivo correlations (IVIVCs) for inhaled drug products could permit increased reliance on in vitro data when developing new inhaled drug products, and could ultimately result in accelerated drug product development, together with reduced research and development spending.

The dry powder inhaler features of the Easyhaler that benefit the management of patients

Introduction: Inhaled therapies are likely to continue to dominate asthma and chronic obstructive pulmonary disease treatment. Dry powder inhalers (DPIs) have several advantages over pressurized metered-dose inhaler (pMDIs), that are most frequently marketed world-wide, but often difficult to use. This literature search focus on DPI features, with respect to Easyhaler, that may affect their use and patients' clinical benefit.Areas covered: DPIs are breath-actuated, easy to use, convenient to use, and more environmentally friendly. During inhalation, the formulation in a DPI is disaggregated by a turbulent airflow energy to generate particles with the greatest likelihood of deposition into the airways. The resistance among DPIs varies from low to high and those with high resistance are wrongly considered as difficult to use. Multidose reservoir-type DPIs have been developed to efficiently deliver a wide range of medications, including the fixed-dose combination of budesonide and formoterol. Easyhaler® shares a similar shape with pMDIs and, as other DPIs, its performance is unaffected by environmental and storage conditions. Due to Easyhaler internal design, dose emission is consistent irrespective of the inhalation flow used by each patient.Expert opinion: Easyhaler® may be considered one of the most convenient inhalers, for daily use, in patients with asthma or COPD.

Real-life budesonide and formoterol dose emission from the medium and high strength fixed dosed combinations in a Spiromax® dry powder inhaler using inhalation profiles from patients with chronic obstructive pulmonary disease

Dry powder inhalers (DPIs) are passive devices used to administer inhaled medication for the management of asthma and chronic obstructive pulmonary disease (COPD). DPIs require patients to generate a sufficient internal turbulent airflow force during each inhalation to deaggregate the powdered drug formulation into an emitted dose containing particles with the greatest likelihood of lung deposition. This internal force is generated by the interaction between the user's inhalation flow and the resistance of the DPI. Traditional compendial in vitro methods of measuring dose emission use a vacuum pump to simulate inhalation. We have adapted this in vitro method by replacing the square wave inhalation profile generated by a vacuum pump with the inhalation profiles of patients using an empty DPI. This method enables accurate assessment of the actual dose they would have inhaled. In the present study, real-life inhalation profiles were selected from 15 patients with COPD who inhaled through an empty placebo Spiromax® DPI. Ex vivo dose emissions were measured for the medium (emitted dose of 160 μg/4.5 μg) and high-strength (320 μg/9 μg) budesonide/formoterol formulations from the Spiromax DPI. These profiles were used to investigate the effect of the primary inhalation parameter-peak inhalation flow (PIF). Some profiles were modified to isolate other inhalation parameters (namely, inhaled volume [V_in] and acceleration rate of the inhalation maneuver [ACIM]). Both the medium-strength and high-strength DuoResp Spiromax displayed flow-dependent dose emission. When the PIF of a patient's inhalation maneuver increased from 26.8 L/min to 69.7 L/min, there was a significant (p < 0.05) effect on the dose-emission characteristics of the medium-strength and high-strength DuoResp Spiromax. At each PIF, an increase in V_in from approximately 500 mL to 2000 mL had no effect on the dose-emission characteristics of either strength. However, at each V_in there was a significant (p < 0.05) effect on the dose-emission characteristics as PIF increased. The effect of ACIM on the dose-emission characteristics was small. The ex vivo methodology used in this study provides a practical approach to identify the actual dose a patient might inhale during routine real-life use of the DuoResp Spiromax.

Evaluation of patients' real-world post-dispensing use and storage environments of tiotropium bromide Respimat® soft mist inhaler on its in vitro dose delivery and lung deposition

BACKGROUND

Oral inhalation is the main drug delivery route for treating obstructive lung conditions. Thus, many inhaler devices with various design and pharmaceutical formulation have been introduced. The fine particle dose (FPD) and mass median aerodynamic diameter (MMAD ≤ 5 μm) of the aerosol delivered dose (DD) dictate the therapeutically effective peripheral lung deposition. This study evaluated the in vitro aerosol emission performance of tiotropium bromide emitted from Spiriva® Respimat® soft mist inhalers (R) after living under patients' real-world, post-dispensing handling environments.

METHODS

This was a two-stage investigation. In the first clinical stage, research ethical approval was obtained to enrol patients already been using R for at least 3 months. Those who signed consent were given both new R to use and temperature and relative humidity (RH) handheld, portable data loggers to keep in the vicinity of the given R. The participants returned the given R and data loggers after 2 weeks. Patient recruitment took place in Amman, Jordan, during the summer (RS) and winter (RW). Subsequently, in the second laboratory stage, other R were strictly stored at an average of 21.0 °C and 46.9% RH as control (RC). The Next Generation Impactor (NGI) was used to evaluate the RS, RW and RC. The NGI was operated at a flow rate of 30 L/min.

RESULTS

The RS were exposed to an average (range) 23.6 °C (18.2-37.5 °C) and 43.8% RH (21.4-60.0% RH) that were statistically comparable (p > 0.05) to that of the RW; 17.3 °C (13.2-26.7 °C) and 52.8% RH (26.3-69.1% RH). The RW and RC retention environments were statistically different (p < 0.05), whilst the RS and RC had comparable (p > 0.05) conditions. No significant differences (p > 0.05) were found in the tiotropium bromide DD (2.39 vs 2.43 μg), FPD (0.88 vs 0.90 μg) and MMAD (5.1 vs 4.98 μm) between the RS and RW, respectively. Compared to the RC inhalers, both the RS and RW devices had significantly higher FPD and relatively smaller tiotropium bromide particles.

CONCLUSIONS

Using the R under the fluctuating summer and winter environments of our patients would not affect its overall tiotropium bromide emission performance. The significant increase in the respirable mass of the RS and RW might be offset by the increase in particles <1 μm particularly in patients with poor inhaler technique.

Aerosol delivery into small anatomical airway model through spontaneous engineered breathing

Pulmonary administration is a noninvasive drug delivery method that, in contrast to systemic administration, reduces drug dosage and possible side effects. Numerous testing models, such as impingers and impactors, have previously been developed to evaluate the fate of inhaled drugs. However, such models are limited by the lack of information regarding several factors, such as pulmonary morphology and breathing motion, which are required to fully interpret actual inhaled-drug deposition profiles within the human respiratory tract. In this study, a spontaneous breathing-lung model that integrates branched morphology and deformable alveolar features was constructed using a multilayered fabrication technology to mimic the complex environment of the human lower respiratory tract. The developed model could emulate cyclic and spontaneous breathing motions to inhale and exhale aerosols generated by a nebulizer under diseaselike conditions. Results of this research demonstrate that aerosols (4.2 μm) could reach up to the deeper lung regions (generation 19 of the branched lung structure) within the obstructivelike model, whereas lesser penetration (generation 17) was observed when using the restrictivelike model. The proposed breathing-lung model can serve as a testing platform to provide a comprehensive understanding of the pharmacokinetics of pulmonary drugs within the lower lungs.

Use of inspiratory profiles from patients with chronic obstructive pulmonary disease (COPD) to investigate drug delivery uniformity and aerodynamic dose emission of indacaterol from a capsule based dry powder inhaler

Most patients using dry powder inhalers (DPIs) are unable to achieve the inhalation parameters recommended for pharmacopoeial in-vitro dose emission testing. The dose emission characteristics of indacaterol Breezhaler (IB) have been measured using COPD patients' inhalation profiles (IPs) when using IB and replayed in-vitro using a breath simulator attached to an Andersen Cascade Impactor. The peak inhalation flow (PIF) of the profiles ranged from 28.3 to 87.8 L/min and inhaled volumes (Vin) from 0.7 to 3 L. The indacaterol total emitted doses (TED), fine particle dose (FPD) and mass median aerodynamic diameter (MMAD) were measured. TED varied between 61% to 83% of the 150 μg nominal dose, the FPD was found to vary between 19% and 30% and the MMAD from 3.7 μm to 2.3 μm with the increase of the profiles' PIF and Vin. The mean (SD) values were 113.4(8.9) μg, 39.7(5.0) μg and 2.7(0.5) μm, respectively. The quantity and the quality of the emitted dose from the indacaterol Breezhaler® are dependent on the capability of a patient generating an optimal inhalation profile. Therefore, when using the IB patients should be encouraged to inhale as fast as they can from the start of their inhalation and for as long as possible.

Determination of Passive Dry Powder Inhaler Aerodynamic Particle Size Distribution by Multi-Stage Cascade Impactor: International Pharmaceutical Aerosol Consortium on Regulation & Science (IPAC-RS) Recommendations to Support Both Product Quality Control and Clinical Programs

The multi-stage cascade impactor (CI) is the mainstay method for the determination of the aerodynamic particle size distribution (APSD) of aerosols emitted from orally inhaled products (OIPs). CIs are designed to operate at a constant flow rate throughout the measurement process. However, it is necessary to mimic an inhalation maneuver to disperse the powder into an aerosol when testing passive dry powder inhalers (DPIs), which constitute a significant portion of available products in this inhaler class. Methods in the pharmacopeial compendia intended for product quality assurance initiate sampling by applying a vacuum to the measurement apparatus using a timer-operated solenoid valve located downstream of the CI, resulting in a period when the flow rate through the impactor rapidly increases from zero towards the target flow rate. This article provides recommendations for achieving consistent APSD measurements, including selection of the CI, pre-separator, and flow control equipment, as well as reviewing considerations that relate to the shape of the flow rate-sampling time profile. Evidence from comparisons of different DPIs delivering the same active pharmaceutical ingredients (APIs) is indicative that the compendial method for APSD measurement is insensitive as a predictor of pharmacokinetic outcomes. Although inappropriate for product quality testing, guidance is therefore provided towards adopting a more clinically realistic methodology, including the use of an anatomically appropriate inlet and mimicking patient inhalation at the DPI while operating the CI at constant flow rate. Many of these recommendations are applicable to the testing of other OIP classes.

The impact of patients' real-life environmental temperature and humidity use conditions of tiotropium dry powder inhaler on its aerosol emission characteristics

INTRODUCTION

Many factors can affect dry powder inhalers' (DPIs) aerosol emission and lung deposition. The fluctuation of environmental temperature and relative humidity (RH) that inhalers experience in realistic daily use has not been extensively evaluated. This work aimed to evaluate the delivered dose (DD) and aerodynamic particle size distribution (APSD) of tiotropium Handihaler DPI (H) after exposure to patients' real-life use environments.

METHODS

Ethical approval was obtained to enrol adult patients already using H. Patients who gave written consent were given new H to use and HygroLog temperature and RH data loggers to keep in the vicinity of the given inhaler. The H and HygroLog were returned after 2 weeks. Patient recruitment was done during the summer (HS) and winter (HW). As control, other HC were stored as per the leaflet storage instructions. The Next Generation Impactor was used to evaluate the inhalers.

RESULTS

The HC were stored under an average of 21.0 °C and 46.9% RH. The patients' HS and HW lived in an average (range) temperature (°C) 23.2 (18.3-38.2) and 17.8 (13.5-24.6), respectively, and RH 50.8% (24.3-65.3%) and 50.4% (30.6-72.4%), respectively. All H groups had comparable environments (p > 0.05). The HC, HS and HW gave similar tiotropium DD (μg) 7.60, 8.01 and 7.61, respectively (p > 0.05). Moreover, the fine particle dose μg (median diameter (μm)) were HC 2.41 (3.84), HS 2.55 (3.81) and HW 2.37 (3.83) (p > 0.05).

CONCLUSIONS

The aerosol emission behaviour of tiotropium Handihaler was tolerant to real-life retention environments of patients in Amman, Jordan.

Patient Satisfaction and Clinical Outcomes with Budesonide plus Formoterol Spiromax for Asthma and Chronic Obstructive Pulmonary Disease: A Real-World, Observational Trial

BACKGROUND

The fixed-dose combination of budesonide/formoterol (B/F) has been available in the Spiromax® dry powder inhaler since 2014.

OBJECTIVES

To assess patient satisfaction, inhaler use errors, and disease control in patients with asthma or chronic obstructive pulmonary disease (COPD) treated with B/F Spiromax.

METHODS

This non-interventional, prospective, 12-week study enrolled consecutive asthma or COPD patients who had recently begun treatment with B/F Spiromax or were switched from another inhaled corticosteroid/long-acting β2-agonist combination to B/F Spiromax in routine clinical practice. Patients recruited from 243 specialist respiratory clinics or general practices in Germany were assessed for patient satisfaction (Satisfaction with Inhalers and Preference questionnaire), inhaler application errors (modified Easy Low Instruction over Time checklist), disease control, and safety.

RESULTS

The population included 3,943 patients: asthma n = 2,707 (68.7%); COPD n = 1,236 (31.3%). At baseline, 60.1% of patients were "satisfied" or "very satisfied" with their previous inhaler, and this increased to 88.8% at week 12 of B/F Spiromax use. Overall, 62.1% of pre-treated patients preferred B/F Spiromax to their old inhaler. The frequency of any handling error observed with B/F Spiromax at week 12 was lower than at baseline (11.9 vs. 25.5% of patients, respectively). After 12 weeks, 77.4% were assessed as having improved (minimally, much, or very much) overall health status versus baseline. Guideline-defined disease severity (as rated by physicians) and patient-reported symptom severity improved during the study in both asthma and COPD patients. B/F Spiromax was well tolerated.

CONCLUSION

B/F Spiromax was associated with high patient satisfaction, low device handling error rate, and improvements in clinical outcomes in real-world clinical practice.

Real-world effectiveness evaluation of budesonide/formoterol Spiromax for the management of asthma and chronic obstructive pulmonary disease in the UK

OBJECTIVES

Budesonide/formoterol (BF) Spiromax ® is an inhaled corticosteroid/long-acting β2-agonist fixed-dose combination (FDC) inhaler, designed to minimise common inhaler errors and provide reliable and consistent dose delivery in asthma and chronic obstructive pulmonary disease (COPD). We evaluated non-inferiority of BF Spiromax after changing from another FDC inhaler, compared with continuing the original inhaler.

METHODS

Patients with asthma and/or COPD who switched to BF Spiromax were matched (1:3) with non-switchers. Data were obtained from the Optimum Patient Care Research Database and Clinical Practice Research Datalink in the UK. The primary end point was the proportion of patients achieving disease control (using the risk domain control (RDC) algorithm); secondary end points were: exacerbation rate, short-acting β2-agonist (SABA) use and treatment stability (achieved RDC; no maintenance treatment change). Non-inferiority was defined as having 95% CI lower bound above -10%, using conditional logistic regression and adjusted for relevant confounders.

RESULTS

Comparing 385 matched patients (asthma 253; COPD 132) who switched to BF Spiromax with 1091 (asthma 743; COPD 348) non-switchers, non-inferiority of BF Spiromax in RDC was demonstrated (adjusted difference: +6.6%; 95% CI -0.3 to 13.5). Among patients with asthma, switchers to BF Spiromax versus BF Turbuhaler® reported fewer exacerbations (adjusted rate ratio (RR) 0.76;95% CI 0.60 to 0.99; p=0.044); were less likely to use high daily doses of SABA (adjusted OR 0.71;95% CI 0.52 to 0.98; p=0.034); used fewer SABA inhalers (adjusted RR 0.92;95% CI 0.86 to 0.99; p=0.019); and were more likely to achieve treatment stability (adjusted OR 1.44;95% CI 1.02 to 2.04; p=0.037). No significant differences in these end points were seen among patients with COPD.

CONCLUSIONS

Among UK patients with asthma and COPD, real-world use of BF Spiromax was non-inferior to BF Turbuhaler in terms of disease control. Among patients with asthma, switching to BF Spiromax was associated with reduced exacerbations, reduced SABA use and improved treatment stability versus continuing on BF Turbuhaler.

Comparison of correct technique and preference for Spiromax®, Easyhaler® and Turbuhaler®: a single-site, single-visit, crossover study in inhaler-naïve adult volunteers

Background: Many patients do not use inhalers correctly. Inhalers associated with good technique have the potential to improve symptom control and are often preferred by patients. Methods: Inhaler-naïve, adult volunteers were randomized to use empty Spiromax®, Easyhaler®, and Turbuhaler® dry powder inhalers (DPIs) in one of six possible sequences in this single-site, single-visit, crossover study conducted in Sweden. Randomization was stratified by age and gender. Participants attempted to use each device intuitively (no instructions) and after reading the instructions for use from the patient information leaflet. Device preference was surveyed after using all devices. Mastery of device handling (i.e. dose preparation) or inhalation was defined as having no healthcare-professional-observed errors. The primary endpoint was mastery of device handling after reading the instructions. Results: More participants mastered device handling with Spiromax vs Easyhaler or Turbuhaler, both intuitively (44%, 0%, and 10%, respectively) and after reading the instructions (99%, 56%, and 81%, respectively). Fewer participants had ≥1 device-handling error with Spiromax than with the other devices. The percentage of participants still showing inhalation errors after reading the instructions ranged between 21% for Spiromax and 40% for Easyhaler. After reading instructions, mastery of handling and inhalation was numerically lower among older (aged >60 years) vs younger participants across all devices. Most participants preferred Spiromax for device handling (59%) and intuitiveness/ease of use (61%). Conclusion: These findings highlight that important differences exist between DPI devices, which could have implications for disease control when selecting a device for a patient.

Evaluation of inhaler technique and achievement and maintenance of mastery of budesonide/formoterol Spiromax® compared with budesonide/formoterol Turbuhaler® in adult patients with asthma: the Easy Low Instruction Over Time (ELIOT) study

BACKGROUND

Incorrect inhaler technique is a common cause of poor asthma control. This two-phase pragmatic study evaluated inhaler technique mastery and maintenance of mastery with DuoResp® (budesonide-formoterol [BF]) Spiromax® compared with Symbicort® (BF) Turbuhaler® in patients with asthma who were receiving inhaled corticosteroids/long-acting β2-agonists.

METHODS

In the initial cross-sectional phase, patients were randomized to a 6-step training protocol with empty Spiromax and Turbuhaler devices. Patients initially demonstrating ≥1 error with their current device, and then achieving mastery with both Spiromax and Turbuhaler (absence of healthcare professional [HCP]-observed errors), were eligible for the longitudinal phase. In the longitudinal phase, patients were randomized to BF Spiromax or BF Turbuhaler. Co-primary endpoints were the proportions of patients achieving device mastery after three training steps and maintaining device mastery (defined as the absence of HCP-observed errors after 12 weeks of use). Secondary endpoints included device preference, handling error frequency, asthma control, and safety. Exploratory endpoints included assessment of device mastery by an independent external expert reviewing video recordings of a subset of patients.

RESULTS

Four hundred ninety-three patients participated in the cross-sectional phase, and 395 patients in the longitudinal phase. In the cross-sectional phase, more patients achieved device mastery after three training steps with Spiromax (94%) versus Turbuhaler (87%) (odds ratio [OR] 3.77 [95% confidence interval (CI) 2.05-6.95], p < 0.001). Longitudinal phase data indicated that the odds of maintaining inhaler mastery at 12 weeks were not statistically significantly different (OR 1.26 [95% CI 0.80-1.98], p = 0.316). Asthma control improved in both groups with no significant difference between groups (OR 0.11 [95% CI -0.09-0.30]). An exploratory analysis indicated that the odds of maintaining independent expert-verified device mastery were significantly higher for patients using Spiromax versus Turbuhaler (OR 2.11 [95% CI 1.25-3.54]).

CONCLUSIONS

In the cross-sectional phase, a significantly greater proportion of patients using Spiromax versus Turbuhaler achieved device mastery; in the longitudinal phase, the proportion of patients maintaining device mastery with Spiromax versus Turbuhaler was similar. An exploratory independent expert-verified analysis found Spiromax was associated with higher levels of device mastery after 12 weeks. Asthma control was improved by treatment with both BF Spiromax and BF Turbuhaler.

TRIAL REGISTRATION

EudraCT 2013-004630-14 (registration date 23 January 2014); NCT02570425 .

Modeling and optimization of nebulizers' performance in non-invasive ventilation using different fill volumes: Comparative study between vibrating mesh and jet nebulizers

BACKGROUNDS

Substituting nebulisers by another, especially in non-invasive ventilation (NIV), involves many process-variables, e.g. nebulizer-type and fill-volume of respirable-dose, which might affect patient optimum-therapy. The aim of the present work was to use neural-networks and genetic-algorithms to develop performance-models for two different nebulizers.

METHODS

In-vitro, ex-vivo and in-vivo models were developed using input-variables including nebulizer-type [jet nebulizer (JN) and vibrating mesh nebulizer (VMN)] fill-volumes of respirable dose placed in the nebulization chamber with an output-variable e.g. average amount reaching NIV patient. Produced models were tested and validated to ensure effective predictivity and validity in further optimization of nebulization process.

RESULTS

Data-mining produced models showed excellent training, testing and validation correlation-coefficients. VMN showed high nebulization efficacy than JN. JN was affected more by increasing the fill-volume. The optimization process and contour-lines obtained for in-vivo model showed increase in pulmonary-bioavailability and systemic-absorption with VMN and 2 mL fill-volumes.

CONCLUSIONS

Modeling of aerosol-delivery by JN and VMN using different fill-volumes in NIV circuit was successful in demonstrating the effect of different variable on dose-delivery to NIV patient. Artificial neural networks model showed that VMN increased pulmonary-bioavailability and systemic-absorption compared to JN. VMN was less affected by fill-volume change compared to JN which should be diluted to increase delivery.

Objective Assessment of Adherence to Inhalers by Patients with Chronic Obstructive Pulmonary Disease

RATIONALE

Objective adherence to inhaled therapy by patients with chronic obstructive pulmonary disease (COPD) has not been reported.

OBJECTIVES

To objectively quantify adherence to preventer Diskus inhaler therapy by patients with COPD with an electronic audio recording device (INCA).

METHODS

This was a prospective observational study. On discharge from hospital patients were given a salmeterol/fluticasone inhaler with an INCA device attached. Analysis of this audio quantified the frequency and proficiency of inhaler use.

MEASUREMENTS AND MAIN RESULTS

Patients with COPD (n = 244) were recruited. The mean age was 71 years, mean FEV₁ was 1.3 L, and 59% had evidence of mild/moderate cognitive impairment. By combining time of use, interval between doses, and critical technique errors, thus incorporating both intentional and unintentional nonadherence, a measure "actual adherence" was calculated. Mean actual adherence was 22.6% of that expected if the doses were taken correctly and on time. Six percent had an actual adherence greater than 80%. Hierarchical clustering found three equally sized well-separated clusters corresponding to distinct patterns. Cluster 1 (34%) had low inhaler use and high error rates. Cluster 2 (25%) had high inhaler use and high error rates. Cluster 3 (36%) had overall good adherence. Poor lung function and comorbidities were predictive of poor technique, whereas age and cognition with poor lung function distinguished those with poor adherence and frequent errors in technique.

CONCLUSIONS

These data may inform clinicians in understanding why a prescribed inhaler is not effective and to devise strategies to promote adherence in COPD.

Significance of breath-hold time in dry powder aerosol drug therapy of COPD patients

Aerosol drugs are effectively used to treat chronic respiratory diseases. The efficiency of the therapy depends also on the amount and distribution of drug deposited within the airways. The objective of this study is to apply numerical techniques to analyse the effect of the duration of breath-hold after the inhalation of six different commercialized dry powder drugs on their lung deposition. For this purpose a computational airway deposition model has been adapted and validated to the special case of therapeutic aerosols. Our results show that lung dose of the studied drugs can be enhanced by 11.3%-26.5% with a 5s breath-hold and by 20.7%-53% with a 25s breath-hold compared to the no-breath-hold case. Although this later duration may not be achieved by COPD patients, present results clearly show the importance of holding the breath as long as possible. Current computations also revealed that there is a strong positive correlation between the enhancement of lung dose as a result of breath-hold and the amount of fine particles in the drugs. Present tendencies aiming at producing drug particles of smaller and smaller sizes will lead to the further enhancement of the importance of producing a sufficiently long breath-hold time after the drug inhalation. In addition, higher lung deposition will be possible by the more correct use of inhalation devices, more precise and detailed patient information materials and personalized drug choice and therapy.

Real life dose emission characterization using COPD patient inhalation profiles when they inhaled using a fixed dose combination (FDC) of the medium strength Symbicort® Turbuhaler®

The dose emitted from dry powder inhalers (DPI) is inhalation flow dependent and so varies with the peak inhalation flow (PIF) of a patient's inhalation maneuver (IM). Dose emission could also be affected by other IM parameters-the inhaled volume (V_in) and the initial acceleration rate of the IM (ACIM). We have adapted the compendial method for in-vitro DPI determinations so that inhalation profiles replace the inhalation square profile generated by a vacuum pump. These real-life patient inhalation profiles were measured when 18 COPD patients inhaled through an empty placebo Symbicort^® Turbuhaler^®. They have been used to identify the dose emission characteristics from a fixed dosed combination of 200μg budesonide plus 6μg formoterol Turbuhaler^®. To isolate each inhalation parameter some profiles were modified to provide a further 9 profiles to study the influence of V_in and 27 to identify the effect of ACIM. The fine particle dose, total emitted dose and mass median aerodynamic diameter were significantly (p<0.05) influenced by PIF (p<0.05) whereas ACIM and V_in had only a small effect. The results show the value of this ex-vivo methodology to provide an insight into the dose that each patient would have inhaled during real-life use.

In vitro aerodynamic characteristics of aerosol delivered from different inhalation methods in mechanical ventilation

Aerodynamic characteristics of aerosol delivery during invasive mechanical ventilation (IMV) are mostly determined by inserting cascade impactor in the circuit. Impactor might have some effect on airflow within IMV. Hence, the aim of the present study was to develop and evaluate new in vitro aerodynamic characterization methodology without affecting airflow in IMV. Breathing simulator was set in standard adult IMV circuit with inspiratory and expiratory pressures of 20 and 5 cm H₂O, 1:3 inspiratory-expiratory ratio, 15 breaths min^-1, and tidal volume of 500 ml. Two ml of salbutamol solution containing 10,000 μg was nebulized using three different vibrating mesh nebulizers (VMNs) and Sidestream jet nebulizer (JET). Sixteen-metered doses, containing 100 μg salbutamol each, were delivered using three different spacers. Each device was placed in inspiration limb of Y-piece of ventilator tubing. Aerodynamic characteristics of aerosol delivered were measured using cooled Andersen cascade impactor, with mixing inlet connected to it. VMNs used had significantly more total mass in the impactor (p < .001) and fine particle dose (p < .001) compared to JET. Spacers used had higher total mass in the impactor percent (p < .001) and fine particle fraction compared to nebulizers. The in vitro IMV methodology setting suggested here showed encouraging results in comparison of different aerosol delivery systems in intubated patient.

Numerical simulation of emitted particle characteristics and airway deposition distribution of Symbicort(®) Turbuhaler(®) dry powder fixed combination aerosol drug

One of the most widespread dry powder fixed combinations used in asthma and chronic obstructive pulmonary disease (COPD) management is Symbicort(®) Turbuhaler(®). The aim of this study was to simulate the deposition distribution of both components of this drug within the airways based on realistic airflow measurements. Breathing parameters of 25 healthy adults (11 females and 14 males) were acquired while inhaling through Turbuhaler(®). Individual specific emitted doses and particle size distributions of Symbicort(®) Turbuhaler(®) were determined. A self-developed particle deposition model was adapted and validated to simulate the deposition of budesonide (inhaled corticosteroid; ICS) and formoterol (long acting β2 agonist; LABA) in the upper airways and lungs of the healthy volunteers. Based on current simulations the emitted doses varied between 50.4% and 92.5% of the metered dose for the ICS, and between 38% and 96.1% in case of LABA component depending on the individual inhalation flow rate. This variability induced a notable inter-individual spread of the deposited lung doses (mean: 33.6%, range: 20.4%-48.8% for budesonide and mean: 29.8%, range: 16.4%-42.9% for formoterol). Significant inter-gender differences were also observed. Average lung dose of budesonide was 29.2% of the metered dose for females and 37% for males, while formoterol deposited with 26.4% efficiency for females and 32.5% for males. Present results also highlighted the importance of breath-holding after inhalation of the drug. About a half of the total lung deposition occurred during breath-hold at 9.6s average breath-hold time. Calculated depositions confirmed appropriate lung deposition of Symbicort(®) Turbuhaler(®) for both genders, however more effort for optimal inhalation technique is advised for persons with low vital capacity. This study demonstrated the possibility of personalized prediction of airway deposition of aerosol drugs by numerical simulations. The methodology developed in this study will be applicable also to other marketed drugs in the future.

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.

Onset of action of budesonide/formoterol Spiromax(®) compared with budesonide/formoterol Turbuhaler(®) in patients with COPD

Budesonide/formoterol (BF) is available in two delivery systems, the dry powder inhaler (DPI) Turbuhaler and a pressurized metered dose inhaler (pMDI) for use in patients with asthma or chronic obstructive pulmonary disease (COPD). Spiromax DPI was recently developed as an alternative to Turbuhaler DPI. In the present study, we examined whether there is a difference in the onset of bronchodilatation between BF 320/9 μg delivered by Spiromax and BF 320/9 μg delivered by Turbuhaler in 16 outpatients with stable moderate-to-severe COPD. Our results confirm the rapid onset of action of formoterol when combined with budesonide in patients with COPD and indicate that the onset of bronchodilation induced by BF Spiromax is faster than that elicited by BF Turbuhaler. Furthermore, they show that BF fixed-dose combination does not induce a decrease in SpO2 or an increase in heart rate in patients with COPD, irrespective of the DPI used to deliver this combination. Given the evidence that both inhalers have an equal safety profile, BF Spiromax offers to prescribers and COPD patients an effective alternative to BF Turbuhaler depending also on their preference, availability and cost.

Budesonide + formoterol fumarate dihydrate for the treatment of asthma

INTRODUCTION

One of the most widely used fixed combinations in asthma management is dry powder budesonide+formoterol fumarate dihydrate which is commercially available as Symbicort Turbuhaler(®) (and generic products), Easyhaler Bufomix(®) and DuoRespSpiromax(®) inhaler. The aim of this paper was to review the fixed dry powder combination of inhaled budesonide+formoterol fumarate dihydrate for asthma treatment in adolescents and adults.

AREAS COVERED

A literature search using relevant search terms, reference lists for reviews and meta-analyses was performed.

EXPERT OPINION

In symptomatic adolescent and adult patients with asthma maintenance and reliever therapy with a single-inhaler fixed combination of dry powder budesonide+formoterol fumarate dihydrate is an evidenced option. The combination treatment is convenient to patients. It reduces the number of exacerbations requiring treatment with oral corticosteroids. In some patients the strategy may also reduce the total intake of inhaled corticosteroids over time. Whether important outcome measures of asthma treatment, such as hospital admission and emergency room visit rates, may be reduced is less well documented since the published studies may have been influenced by publication bias. Non-pharmaceutical company-sponsored research evaluating such measures is needed. There is no evidence for the use of single inhaler fixed combinations of inhaled corticosteroids+long-acting β(2)-agonists in children (<12 years of age), and budesonide+formoterol fumarate dihydrate should not be prescribed to the age group.

Concept review of dry powder inhalers: correct interpretation of published data

Dry powder inhalers (DPIs) are widely used in the clinical practice for delivering therapeutics to patients with lung diseases, such as chronic obstructive pulmonary disease. An overview of current DPIs available on the market from high resistance to low resistance has been reported in a recent review article. We assessed this concept review article and believe this letter provides important additional information regarding the correct interpretation of the data on low resistance DPIs.