Improving inhaler technique, adherence to therapy and the precision of dosing: major challenges for pulmonary drug delivery

Design of dry powder inhalers to improve patient outcomes: it's not just about the device

INTRODUCTION

Up to 50% of asthma/COPD patients make critical errors in dose preparation and dose inhalation with current marketed DPIs which negatively impact clinical outcomes. Others fail to adhere to their chronic treatment regimen.

AREAS COVERED

For this review, we describe how a human-factors approach to design of a dry powder inhaler can be used to improve usability, proficiency, and functionality of DPIs, while effectively mitigating critical errors associated with DPIs. The review highlights the critical importance of utilizing improved formulations with monomodal aerodynamic particle size distributions to reduce variability associated with oropharyngeal filtering of particles, flow rate dependence, and co-formulation effects.

EXPERT OPINION

Much of the variability in dose delivery with DPIs is associated with limitations of the bimodal APSDs inherent in current lactose blend formulations. Evidence supports that improved lung targeting and dose consistency can be achieved with drug-device combination products comprising spray-dried powders. Unfortunately, no data exists to assess whether these advances observed in in vitro and in vivo dose delivery studies will translate into improved clinical outcomes. Given the significant percentage of patients that receive suboptimal drug delivery with current DPIs it would behoove the industry to assess the efficacy of new approaches.

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.

Advancements in Chitosan-Based Nanoparticles for Pulmonary Drug Delivery

The evolution of respiratory diseases represents a considerable public health challenge, as they are among the leading causes of death worldwide. In this sense, in addition to the high prevalence of diseases such as asthma, chronic obstructive pulmonary disease, pneumonia, cystic fibrosis, and lung cancer, emerging respiratory diseases, particularly those caused by members of the coronavirus family, have contributed to a significant number of deaths on a global scale over the last two decades. Therefore, several studies have been conducted to optimize the efficacy of treatments against these diseases, focusing on pulmonary drug delivery using nanomedicine. Thus, the development of nanocarriers has emerged as a promising alternative to overcome the limitations of conventional therapy, by increasing drug bioavailability at the target site and reducing unwanted side effects. In this context, nanoparticles composed of chitosan (CS) show advantages over other nanocarriers because chitosan possesses intrinsic biological properties, such as anti-inflammatory, antimicrobial, and mucoadhesive capacity. Moreover, CS nanoparticles have the potential to enhance drug stability, prolong the duration of action, improve drug targeting, control drug release, optimize dissolution of poorly soluble drugs, and increase cell membrane permeability of hydrophobic drugs. These properties could optimize the performance of the drug after its pulmonary administration. Therefore, this review aims to discuss the potential of chitosan nanoparticles for pulmonary drug delivery, highlighting how their biological properties can improve the treatment of pulmonary diseases, including their synergistic action with the encapsulated drug.

Drug combinations for inhalation: Current products and future development addressing disease control and patient compliance

Pulmonary delivery is an alternative route of administration with numerous advantages over conventional routes of administration. It provides low enzymatic exposure, fewer systemic side effects, no first-pass metabolism, and concentrated drug amounts at the site of the disease, making it an ideal route for the treatment of pulmonary diseases. Owing to the thin alveolar-capillary barrier, and large surface area that facilitates rapid absorption to the bloodstream in the lung, systemic delivery can be achieved as well. Administration of multiple drugs at one time became urgent to control chronic pulmonary diseases such as asthma and COPD, thus, development of drug combinations was proposed. Administration of medications with variable dosages from different inhalers leads to overburdening the patient and may cause low therapeutic intervention. Therefore, products that contain combined drugs to be delivered via a single inhaler have been developed to improve patient compliance, reduce different dose regimens, achieve higher disease control, and boost therapeutic effectiveness in some cases. This comprehensive review aimed to highlight the growth of drug combinations by inhalation over time, obstacles and challenges, and the possible progress to broaden the current options or to cover new indications in the future. Moreover, various pharmaceutical technologies in terms of formulation and device in correlation with inhaled combinations were discussed in this review. Hence, inhaled combination therapy is driven by the need to maintain and improve the quality of life for patients with chronic respiratory diseases; promoting drug combinations by inhalation to a higher level is a necessity.

Salbutamol transport and deposition in healthy cat airways under different breathing conditions and particle sizes

Salbutamol is a bronchodilatator commonly used for the treatment of feline inflammatory lower airway disease, including asthma or acute bronchospasm. As in humans, a pressurized metered dose inhaler (pMDI) is used in conjunction with a spacer and a spherical mask to facilitate salbutamol administration. However, efficacy of inhalation therapy is influenced by different factors including the non-cooperative character of cats. In this study, the goal was to use computational fluid dynamics (CFD) to analyze the impact of breathing patterns and salbutamol particle size on overall drug transport and deposition using a specific spherical mask and spacer designed for cats. A model incorporating three-dimensional cat airway geometry, a commercially available spherical mask, and a 10 cm spacer, was used for CFD analysis. Two peak inspiratory flows were tested: 30 mL/s and 126 mL/s. Simulations were performed with 30s breathing different inspiratory and expiratory times, respiratory frequencies and peaks. Droplet spray transport and deposition were simulated with different particle sizes typical of the drug delivery therapies (1, 5, 10, and 15 μm). The percentage of particle deposition into the device and upper airways decreased with increasing particle diameter during both flows imposed in this cat model. During increased mean ventilatory rate (MVR) conditions, most of the salbutamol was lost in the upper airways. And during decreased MVR conditions, most of the particles remained in suspension (still in hold-up) between the mask and the carina, indicating the need for more than 30 s to be transported. In both flows the percentage of particles traveling to the lung was low at 1.5%-2.3%. In conclusion, in contrast to what has been described in the human literature, the results from this feline model suggest that the percentage of particles deposited on the upper airway decreases with increasing particle diameter.

Evaluation of Peak Inspiratory Flow Rate in Hospitalized Palliative Care Patients with COPD

Dry powder inhalers are an effective yet costly COPD medication-delivery device. Patients must possess a minimum peak inspiratory flow rate (PIFR) for inhaled medication to be properly deposited into the lungs. Hospitalized palliative-care patients with diminished lung function due to advanced COPD may not possess the minimum PIFR (30 L/min) for adequate drug delivery. This study aims to quantify PIFR values for hospitalized palliative-care patients with advanced COPD to evaluate whether these patients meet the minimum PIFR requirements. Hospitalized patients ≥18 years old with a palliative-care consultation were eligible if they had a diagnosis of advanced COPD (GOLD C or D). Patients were excluded if they lacked decision-making capacity or had a positive COVID-19 test within the previous 90 days. Three PIFR values were recorded utilizing the In-Check^TM device, with the highest of the three PIFR attempts being utilized for statistical analysis. Eighteen patients were enrolled, and the mean of the highest PIFR readings was 72.5 L/min (±29 L/min). Post hoc analysis indicated 99.9% power when comparing the average best PIFR to the minimum PIFR (30 L/min) but only 51.4% power when compared to the optimal PIFR (60 L/min). This study found that palliative-care patients possess the minimum PIFR for DPI drug delivery.

Post-COVID Syndrome: The Research Progress in the Treatment of Pulmonary sequelae after COVID-19 Infection

Post-COVID syndrome or long COVID is defined as the persistence of symptoms after confirmed SARS-CoV-2 infection, the pathogen responsible for coronavirus disease. The content herein presented reviews the reported long-term consequences and aftereffects of COVID-19 infection and the potential strategies to adopt for their management. Recent studies have shown that severe forms of COVID-19 can progress into acute respiratory distress syndrome (ARDS), a predisposing factor of pulmonary fibrosis that can irreversibly compromise respiratory function. Considering that the most serious complications are observed in the airways, the inhalation delivery of drugs directly to the lungs should be preferred, since it allows to lower the dose and systemic side effects. Although further studies are needed to optimize these techniques, recent studies have also shown the importance of in vitro models to recreate the SARS-CoV-2 infection and study its sequelae. The information reported suggests the necessity to develop new inhalation therapies in order to improve the quality of life of patients who suffer from this condition.

Drug Therapies for COPD: A Bibliometric Review From 1980 to 2021

Objective: To analyze all chronic obstructive pulmonary disease (COPD) drugs-related articles that were indexed in the Web of Science Core Collection (WOSCC) database until August 28, 2021 using bibliometric analysis, in order to provide a reliable reference for the treatment of COPD.

Methods: A comprehensive search was conducted to analyze all COPD drugs-related articles using WOSCC database from inception to August 28, 2021. Abstracts and potentially eligible articles, which were retrieved during literature search, were screened by two reviewers. Besides, the CiteSpace (5.8.R1) software was utilized to analyze the overall structure of the network, the network clusters, the links between clusters, the key nodes or pivot points, and the pathways.

Results: A total of 2552 COPD-drugs related articles were retrieved. From the perspective of categorization of published articles based on country, the United States is the country with the largest number of published articles and completed clinical trials, highlighting the important role of this country in the treatment of COPD. However, in terms of the proportion of ongoing clinical trials, China has the highest proportion, suggesting that China will play a more pivotal role in the medication of COPD in the future. From the perspective of cooperation among countries, the cooperation among European countries was closer than that among Asian countries. In the recent three decades, the top 20 institutions, with a particular concentration on the treatment of COPD, were from North America and Europe. The co-citation analysis showed that, among 2,552 articles, 53154 citations were recorded, and the co-citation network indicated that 24 clusters could be achieved.

Conclusion: The administration of bronchodilators and pulmonary drug delivery systems, as well as consideration of elderly COPD patients remained the hotspots, while triple therapy and comorbidity of COPD, as well as the prevention and treatment of elderly COPD patients had been frontiers in recent years.

Understanding barriers to and strategies for medication adherence in COPD: a qualitative study

Background

Medication adherence in chronic obstructive pulmonary disease (COPD) is low, though not enough is known about the factors that affect adherence in COPD. This study uses qualitative methods to understand the patient perspective on facilitators and barriers to medication adherence in COPD as well as patient-reported strategies for self-management of disease.

Methods

Semi-structured interviews were conducted with 30 individuals (n = 30). Transcripts were analyzed using iterative qualitative coding by 2 independent coders, and codes were categorized using thematic analysis.

Results

Challenges with adherence reported were gaps in understanding, forgetfulness of the patient, physician availability, cost navigation, and overcoming substance use. Most commonly, the financial burden of COPD medications caused patients to source other countries to obtain medications, rely on sample medications collected during doctors’ visits, and to alter medication dosage and frequency to extend the length of a prescription. Tools and resources reported by patients to support self-management of COPD included pharmacist assistance, physician office information, and community resources. Individuals further reported that the use of logs or diaries to track medication usage, visual or temporal cues to take medications, and support from family members were helpful in promoting adherence to their COPD medication regimen.

Conclusions

Medication adherence in individuals with COPD is affected by challenges with self-management of disease and financial burden of medications. However, patients reported multiple tools and resources to support adherence. Physician recognition of these factors impacting self-management, as well as awareness of strategies to promote adherence and manage disease, may improve patient outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01892-5.

Fine Particle Fraction: The Good and the Bad

Fine particle fraction (FPF) is defined in general terms as the fraction or percentage of the drug mass contained in an aerosol cloud that may be small enough to enter the lungs and exert a clinical effect. An aerodynamic diameter of 5 μm represents the approximate border between "fine" and "coarse" particles, but there is no universally agreed upon definition of FPF in terms of an aerodynamic particle size range. FPF alone does not adequately describe a heterodisperse aerodynamic particle size distribution, and it needs to be combined with another measure or measures indicating the width of the distribution. When determined using techniques specified in United States and European Pharmacopeias, FPF is measured by cascade impactors that have straight-sided ninety degree inlets through which air is drawn at a constant rate. It is not the purpose of in vitro tests to predict in vivo behavior, and FPF is primarily a measure of aerosol quality. Despite this, FPF broadly predicts the amount of drug from an inhaler device depositing in the lungs, but it systematically overestimates whole lung deposition and may not correctly predict the relative lung depositions for two inhalers of different types. The relationship between FPF and both drug pharmacokinetics and clinical response is incompletely understood at the present time, and more studies are needed to investigate these relationships. Modifications to impactor technologies, including inlets that mimic the human extrathoracic airways and the use of realistic breathing patterns, would be expected to improve the predictive power of in vitro tests for drug delivery in vivo.

Concepts of advanced therapeutic delivery systems for the management of remodeling and inflammation in airway diseases

Chronic respiratory disorders affect millions of people worldwide. Pathophysiological changes to the normal airway wall structure, including changes in the composition and organization of its cellular and molecular constituents, are referred to as airway remodeling. The inadequacy of effective treatment strategies and scarcity of novel therapies available for the treatment and management of chronic respiratory diseases have given rise to a serious impediment in the clinical management of such diseases. The progress made in advanced drug delivery, has offered additional advantages to fight against the emerging complications of airway remodeling. This review aims to address the gaps in current knowledge about airway remodeling, the relationships between remodeling, inflammation, clinical phenotypes and the significance of using novel drug delivery methods.

Inhaled cytotoxic chemotherapy: clinical challenges, recent developments, and future prospects

INTRODUCTION

Since 1968, inhaled chemotherapy has been evaluated and has shown promising results up to phase II but has not yet reached the market. This is due to technological and clinical challenges that require to be overcome with the aim of optimizing the efficacy and the tolerance of drug to re-open new developments in this field. Moreover, recent changes in the therapeutic standard of care for treating the patient with lung cancer also open new opportunities to combine inhaled chemotherapy with standard treatments.

AREAS COVERED

Clinical and technological concerns are highlighted from the reported clinical trials made with inhaled cytotoxic chemotherapies. This work then focuses on new pharmaceutical developments using dry powder inhalers as inhalation devices and on formulation strategies based on controlled drug release and with sustained lung retention or based on nanomedicine. Finally, new clinical strategies are described in regard to the impact of the immunotherapy on the patient's standard of care.

EXPERT OPINION

The choice of the drug, inhalation device, and formulation strategy as well as the position of inhaled chemotherapy in the patient's clinical care are crucial factors in optimizing local tolerance and efficacy as well as in its scalability and applicability in clinical practice.

Inhaler Use Technique in Chronic Obstructive Pulmonary Disease Patients: Errors, Practices and Barriers

Background

Inhaled medications are the main therapeutic treatment of chronic obstructive pulmonary disease (COPD) and inhaler technique remained important that can increase medication efficacy, reducing dose and side effects. Poor inhaler technique is multi-factorial and the quality of inhaler technique has not previously assessed in Pakistan. We conducted a study to examine a range of competing factors that impact COPD patient willingness, practices, and preference in using their inhalers.

Methods

A cross-sectional of 765 patients with COPD were interviewed and assessed by qualitative questionnaires. Objective inhalation technique and steps assessment was performed; satisfaction, preferences, perception, and practice of different types of inhaler devices were evaluated at a single cross-sectional visit at the study enrolment.

Results

The study included 765 participants of mean age 58.7 years (SD ±7.8); 32% males and 68% females. Almost all of the females were exposed to biomass fuel smoke exposure (99%) and pipe (Huka) smokers 53%, while most male participants were cigarette smokers (92%). Only 6.3% of participants were able to perform correct steps of inhaler use, and few educated patients completed 7-steps. 66% of patients were using dry powder inhalers (DPI) inhaler devices and mostly performed the steps 1, 2, and 4 (98%) correctly, while 44% who were using metered-dose inhalers (MDI) completed only steps 2 and 4 correctly (88%). The majority of participants reported the particular inhaler devices was prescribed by the visiting consultants (54%). Interestingly, they were using two inhalers together (47%) relieving symptoms of dyspnea (83%) and cough (73%). The inhaler use technique was demonstrated to most of the patients by the pharmacy salesman (38.4%), while 15.8% reported that their doctors taught them the inhaler technique. 54.2% reported reason for poor adherence to inhaler use as they understand it might not work lately and 75.2% were not aware of any side effects associated with the regular use of an inhaler.

Conclusions

Poor inhaler technique is highly prevalent and the associated errors did not appear to be dependent on device type. Most of the participants had not receive proper training about the correct use and were not involved in decision making about the choice of inhaler device.

The Impact of a Forced Non-Medical Switch of Inhaled Respiratory Medication Among Patients with Asthma or Chronic Obstructive Pulmonary Disease: A Patient Survey on Experience with Switch, Therapy Satisfaction, and Disease Control

PURPOSE

Budesonide/formoterol pressurized metered-dose inhaler (pMDI) was removed from a Medicare Part D formulary, and patients switched to fluticasone-based dry powder inhaler (DPI) therapies. This study describes the experience, satisfaction, and disease control among patients with asthma or chronic obstructive pulmonary disease (COPD) who switched due to removal from the formulary.

PATIENTS AND METHODS

A patient survey was conducted among adults with asthma or COPD who used budesonide/formoterol pMDI for ≥3 months prior to the formulary block and the new medication for ≥3 weeks after switching, recruited by providers in a research panel. Survey comprised both validated instruments (PASAPQ, OEQ, ACQ-6, and CAT) and stand-alone questions. Patient characteristics, switch experience, device and treatment satisfaction, onset of effect, and disease control were compared between disease (asthma and COPD) and medication (once and twice daily) cohorts. Minimal significance for group differences: P≤0.05.

RESULTS

Among 100 patients, 93% received communication from their doctor or nurse about the switch and 73% received training on using the new inhaler. Patients used their new treatment for an average of 7 months prior to completing the survey. Patient satisfaction with the new therapy was high (PASAPQ; mean overall satisfaction: 6.2 for asthma; 6.0 for COPD; P=0.338). However, asthma was not well controlled (ACQ-6) in 62% of patients with asthma, and 56% of patients with COPD reported high/very high impact of their illness on their lives (CAT). Sixty-eight percent and 70% of patients with asthma and COPD, respectively, required reliever medication (≥3 puffs) most days during the week prior to the survey. There were no significant differences in disease control (ACQ-6, CAT) between once-daily and twice-daily treatments (P>0.05 for both asthma and COPD).

CONCLUSION

Even when reporting satisfaction with their new medication, objective measures showed substantial morbidity, regardless of DPI device or dosing regimen.

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.

Using web-based videos to improve inhalation technique in COPD patients requiring hospitalization: A randomized controlled trial

BACKGROUND

Inhalation errors frequently occur in patients receiving inhalation treatment, which can significantly impair treatment success. While this underscores the importance of inhalation training, the role of modern web-based instructional videos has not yet been investigated.

METHODS

A randomized controlled trial using standardized checklists (10 items: preparation, N = 3, inhalation routine, N = 6, and closure of inhalation, N = 1) was carried out to determine the relative effects of web-based, device-specific videos versus standard personal instruction on reducing multiple (≥2) inhalation errors in severe COPD patients requiring hospitalisation. Investigators assessing inhalation errors were blinded to the intervention.

RESULTS

Multiple handling errors were recorded at baseline in 152 out of 159 patients (95.6%). Each teaching method led to a similar reduction in errors (videos: from 4.2±1.6 to 1.5±1.5 errors; personal instruction: from 3.8±1.5 to 1.3±1.6; p<0.0001), although non-inferiority of web-based video teaching could not be confirmed statistically due to an unpredictably high number of patients in both groups still making multiple handling errors (44.0% versus 40.3%, mean difference 3.7%; 95%CI [-12.0-19.4%]).

CONCLUSION

Multiple inhalation errors regularly occur in severe COPD patients requiring hospitalisation. Web-based video teaching is capable of reducing inhalation errors. However, compared to personal instruction non-inferiority could not be established. This was due to an unexpectedly high number of patients with persisting inhalation errors despite training.

TRIAL REGISTRATION

Clinical trial Registration: German Clinical Trial Register, DRKS 00004320.

Delivering drugs to the lungs: The history of repurposing in the treatment of respiratory diseases

The repurposing of drug delivery by the pulmonary route has been applied to treatment and prophylaxis of an increasingly wide range of respiratory diseases. Repurposing has been most successful for the delivery of inhaled bronchodilators and corticosteroids in patients with asthma and chronic obstructive pulmonary disease (COPD). Repurposing utilizes the advantages that the pulmonary route offers in terms of more targeted delivery to the site of action, the use of smaller doses, and a lower incidence of side-effects. Success has been more variable for other drugs and treatment indications. Pulmonary delivery is now well established for delivery of inhaled antibiotics in cystic fibrosis (CF), and in the treatment of pulmonary arterial hypertension (PAH). Other inhaled treatments such as those for idiopathic pulmonary fibrosis (IPF), lung transplant rejection or tuberculosis may also become routine. Repurposing has progressed in parallel with the development of new drugs, inhaler devices and formulations.

Identifying Critical Errors: Addressing Inhaler Technique in the Context of Asthma Management

Medication use has always played a highly significant role in the overall management of asthma, with appropriate use being linked to good asthma control. However, while patients with asthma enjoy the 'luxury' of having medications delivered directly to the lungs via inhaler devices, with that comes the additional challenge of ensuring that inhaler devices are used correctly. Research and practice provides evidence to the challenges associated with inhaler use and the particular steps that patients perform incorrectly. While this problem is well documented, acknowledged and reported, little has changed in 40 years, and the proportion of patients using inhaler devices remains unacceptably high. This review focuses on aspects specific to the errors that patient's make, the significance of these errors, and the important considerations for health care practitioners in supporting patients in correctly using their inhalers. This review highlights the complexities associated with patient's making inhaler technique errors and highlights the opportunities that lie in future technological developments of inhaler devices. Now more than ever, in the era of precision medicine, it is important that we address inhaler technique use once and for all.

Drug delivery to the lungs: challenges and opportunities

Pulmonary drug delivery is relatively complex because the respiratory tract has evolved defense mechanisms to keep inhaled drug particles out of the lungs and to remove or inactivate them once deposited. In addition to these mechanical, chemical and immunological barriers, pulmonary drug delivery is adversely affected by the behavioral barriers of poor adherence and poor inhaler technique. Strategies to mitigate the effects of these barriers include use of inhaler devices and formulations that deliver drug to the lungs efficiently, appropriate inhaler technique and improved education of patients. Owing to the advantages offered by the pulmonary route, the challenges that the route poses are worth addressing, and if successfully addressed, the pulmonary route offers huge opportunities, often fulfilling unmet clinical needs.

Continued Innovation in Respiratory Care: The Importance of Inhaler Devices

When it comes to the use in inhalers in the management of chronic obstructive pulmonary diseases, there are many options, considerations and challenges, which health care professionals need to address. Considerations for prescribing and dispensing, administering and following up, education, and adherence; all of these factors impact on treatment success and all are intrinsically linked to the device selected. This review brings together relevant evidence, real-life data and practice tools to assist health care professionals in making decisions about the use of inhalers in the management of chronic obstructive pulmonary diseases. It covers some of the key technical device issues to be considered, the evidence behind the role of inhalers in disease control, population studies which link behaviors and adherence to inhaler devices as well as practice advice on inhaler technique education and the advantages and disadvantages in selecting different inhaler devices. Finally, a list of key considerations to aid health care providers in successfully managing the use of inhaler devices are summarized.

Advances in Audio-Based Systems to Monitor Patient Adherence and Inhaler Drug Delivery

Hundreds of millions of people worldwide have asthma and COPD. Current medications to control these chronic respiratory diseases can be administered using inhaler devices, such as the pressurized metered dose inhaler and the dry powder inhaler. Provided that they are used as prescribed, inhalers can improve patient clinical outcomes and quality of life. Poor patient inhaler adherence (both time of use and user technique) is, however, a major clinical concern and is associated with poor disease control, increased hospital admissions, and increased mortality rates, particularly in low- and middle-income countries. There are currently limited methods available to health-care professionals to objectively and remotely monitor patient inhaler adherence. This review describes recent sensor-based technologies that use audio-based approaches that show promising opportunities for monitoring inhaler adherence in clinical practice. This review discusses how one form of sensor-based technology, audio-based monitoring systems, can provide clinically pertinent information regarding patient inhaler use over the course of treatment. Audio-based monitoring can provide health-care professionals with quantitative measurements of the drug delivery of inhalers, signifying a clear clinical advantage over other methods of assessment. Furthermore, objective audio-based adherence measures can improve the predictability of patient outcomes to treatment compared with current standard methods of adherence assessment used in clinical practice. Objective feedback on patient inhaler adherence can be used to personalize treatment to the patient, which may enhance precision medicine in the treatment of chronic respiratory diseases.

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.

Practice makes perfect: self-reported adherence a positive marker of inhaler technique maintenance

Poor inhaler technique and non-adherence to treatment are major problems in the management of asthma. Patients can be taught how to achieve good inhaler technique, however maintenance remains problematic, with 50% of patients unable to demonstrate correct technique. The aim of this study was to determine the clinical, patient-related and/or device-related factors that predict inhaler technique maintenance. Data from a quality-controlled longitudinal community care dataset was utilized. 238 patients using preventer medications where included. Data consisted of patient demographics, clinical data, medication-related factors and patient-reported outcomes. Mixed effects logistic regression was used to identify predictors of inhaler technique maintenance at 1 month. The variables found to be independently associated with inhaler technique maintenance using logistic regression (Χ ² (3,n = 238) = 33.24, p < 0.000) were inhaler technique at Visit 1 (OR 7.1), device type (metered dose inhaler and dry powder inhalers) (OR 2.2) and self-reported adherent behavior in the prior 7 days (OR 1.3). This research is the first to unequivocally establish a predictive relationship between inhaler technique maintenance and actual patient adherence, reinforcing the notion that inhaler technique maintenance is more than just a physical skill. Inhaler technique maintenance has an underlying behavioral component, which future studies need to investigate.

ASTHMA

BEHAVIORAL ELEMENT TO CORRECT LONG-TERM INHALER TECHNIQUES: Patients who consciously make an effort to perfect asthma inhaler technique will maintain their skills long-term. Elizabeth Azzi at the University of Sydney, Australia, and co-workers further add evidence that there is a strong behavioral component to patients retaining correct inhaler technique over time. Poor inhaler technique can limit asthma control, affecting quality of life and increasing the chances of severe exacerbations. Azzi's team followed 238 patients to determine the key predictors of inhaler technique maintenance from factors including age, asthma knowledge and perceived future risks. Correct inhaler technique at initial assessment was the strongest predictor of long-term success, but this was strengthened further when patients reported good adherence to their own medication regimen. This suggests that maintaining correct inhaler technique is more than just a physical skill. Careful guidance towards this 'practice makes perfect' approach may improve patients' long-term technique maintenance.

Effectiveness and success factors of educational inhaler technique interventions in asthma & COPD patients: a systematic review

With the current wealth of new inhalers available and insurance policy driven inhaler switching, the need for insights in optimal education on inhaler use is more evident than ever. We aimed to systematically review educational inhalation technique interventions, to assess their overall effectiveness, and identify main drivers of success. Medline, Embase and CINAHL databases were searched for randomised controlled trials on educational inhalation technique interventions. Inclusion eligibility, quality appraisal (Cochrane's risk of bias tool) and data extraction were performed by two independent reviewers. Regression analyses were performed to identify characteristics contributing to inhaler technique improvement. Thirty-seven of the 39 interventions included (95%) indicated statistically significant improvement of inhaler technique. However, average follow-up time was relatively short (5 months), 28% lacked clinical relevant endpoints and all lacked cost-effectiveness estimates. Poor initial technique, number of inhalation procedure steps, setting (outpatient clinics performing best), and time elapsed since intervention (all, p < 0.05), were shown to have an impact on effectiveness of the intervention, explaining up to 91% of the effectiveness variation. Other factors, such as disease (asthma vs. chronic obstructive pulmonary disease), education group size (individual vs. group training) and inhaler type (dry powder inhalers vs. pressurised metered dose inhalers) did not play a significant role. Notably, there was a trend (p = 0.06) towards interventions in adults being more effective than those in children and the intervention effect seemed to wane over time. In conclusion, educational interventions to improve inhaler technique are effective on the short-term. Periodical intervention reinforcement and longer follow-up studies, including clinical relevant endpoints and cost-effectiveness, are recommended.

Optimizing drug delivery in COPD: The role of inhaler devices

BACKGROUND

Inhaled medication is the cornerstone of the pharmacological treatment for patients with asthma and chronic obstructive pulmonary disease (COPD). Several inhaler devices exist, and each device has specific characteristics to achieve the optimal inhalation of drugs. The correct use of inhaler devices is not granted and patients may incur in mistakes when using pressurized metered-dose inhalers (pMDIs) or dry-powder inhaler (DPIs). The incorrect use of inhaler devices can lead to a poorly controlled disease status. Unfortunately, guidelines provide limited guidance regarding the choice of devices. This article presents a review of the literature on different inhaler device requirements. Data from literature (PubMed and Google Scholar) on the commercially available inhaler devices have been evaluated and the history of inhaler medicine described. Furthermore, advantages and disadvantages of each type of device have been analyzed. The evaluation of literature indicated the availability of robust data on the devices characteristics and factors influencing selection of delivery devices. Each type of device has its own pro and cons. The age, cognitive status, visual acuity, manual dexterity, manual strength and ability to coordinate the inhaler actuation with inhalation may be as important as the disease severity in determining the correct approach to delivery of respiratory medication. The administration of effective therapies via a device that is simple to use and accepted by patients may help to improve treatment outcomes in patients with COPD.

Patients' perspectives and preferences in the choice of inhalers: the case for Respimat(®) or HandiHaler(®)

Poor inhaler technique hampers the efficacy of drug therapy in asthma and chronic obstructive pulmonary disease. Not only does this affect individual patient care, but it also impacts on the wider health care economics associated with these conditions. Treatment guidelines recommend a systematic approach to drug class selection; however, standardization of inhaler selection is currently difficult owing to the complexity of the interaction between the inhaler device and the patient. Specifically, individual patient preference can influence how successful a treatment is overall. This article reviews inhaler devices from the patient perspective, with a particular focus on the dry powder inhaler HandiHaler(®) and Respimat(®) Soft Mist™ Inhaler. It discusses factors that influence device preference and treatment compliance and reviews tools that can aid health care professionals to better match inhaler devices to individual patients' needs.

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.

Mapping the Asthma Care Process: Implications for Research and Practice

BACKGROUND

Whether people with asthma gain and maintain control over their condition depends not only on the availability of effective drugs, but also on multiple patient and health care professional (HCP) behaviors. Research in asthma rarely considers how these behaviors interact with each other and drug effectiveness to determine health outcomes, which may limit real-life applicability of findings.

OBJECTIVE

The objective of this study was to develop a logic process model (Asthma Care Model; ACM) that explains how patient and HCP behaviors impact on the asthma care process.

METHODS

Within a European research project on asthma (ASTRO-LAB), we reviewed asthma care guidelines and empirical literature, and conducted qualitative interviews with patients and HCPs. Findings were discussed with the project team and respiratory care experts and integrated in a causal model.

RESULTS

The model outlines a causal sequence of treatment events, from diagnosis and assessment to treatment prescription, drug exposure, and health outcomes. The relationships between these components are moderated by patient behaviors (medication adherence, symptom monitoring, managing triggers, and exacerbations) and HCP behaviors (medical care and self-management support). Modifiable and nonmodifiable behavioral determinants influence the behaviors of patients and HCPs. The model is dynamic as it includes feedback loops of behavioral and clinical outcomes, which influence future patient and HCP decision making. Key evidence for each relationship is summarized to derive research priorities and clinical recommendations.

CONCLUSIONS

The ACM model is of interest to both researchers and practitioners, and intended as a first version (ACM-v1) of a common framework for generating and translating research evidence in asthma care.

An acoustic method to automatically detect pressurized metered dose inhaler actuations

Chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) affect over 400 million people and are incurable. The pressurized metered dose inhaler (pMDI) has been the most popular inhaler device in inhaled therapy in recent times. However the pMDIs require good coordination between inhaling and actuating the inhaler to deliver the aerosolized drug most effectively. Poor coordination can greatly reduce the amount of drug delivered to a patient and therefore reducing the control of respiratory disease symptoms. Acoustic methods have been recently employed to monitor inhaler technique quite effectively. This study employs a noninvasive acoustic method to detect actuation sounds in a portable monitoring device. A total of 158 actuation sounds were obtained from a group of healthy subjects (n=5) and subjects suffering from respiratory diseases (n=15). The developed algorithm generated an overall accuracy of 99.7% demonstrating that this method may have clinical potential to monitor pMDI actuation coordination. The informative feedback from this method may also be employed in clinical training to highlight patient actuation technique.

About the Therapy of Laryngotracheitis (Croup): Significance of Rectal Dosage Forms

Glucocorticoids are drugs of choice for treatment of laryngotracheitis (croup). They may be administered orally as tablets or juice, locally as inhalation or rectally as suppository or capsule. If doctors decide to use a rectal administration for practical reasons, it is obvious from a pharmacokinetic and pharmacodynamic point of view that prednisolone capsules have an earlier and stronger anti-inflammatory effect than a prednisone suppository.

Generation of tailored aerosols for inhalative drug delivery employing recent vibrating-mesh nebulizer systems

Direct drug delivery to the lungs is considered the gold standard for the treatment of a variety of respiratory diseases, owing to the increased therapeutic selectivity of the inhalative approach. Airborne formulations with defined size characteristics are required to improve the deposition pattern within the airways. In this respect, different nebulizer systems have been conceived, which has enabled the generation of respirable medicament mists. Here, vibrating-mesh technology revealed significant potential to overcome the main shortcomings associated with ‘traditional’ devices. Tailored orifice dimensions and defined formulation characteristics are of special interest for the generation of suitable aerosol droplets for inhalative purposes. Ongoing developments in device and formulation design will optimize the clinical outcome of inhalative drug delivery under application of vibrating-mesh technology.

Opportunities in respiratory drug delivery

A wide range of asthma and chronic obstructive pulmonary disease products are soon to be released onto the inhaled therapies market and differentiation between these devices will help them to gain market share over their competitors. Current legislation is directing healthcare towards being more efficient and cost-effective in order to continually provide quality care despite the challenges of aging populations and fewer resources. Devices and drugs that can be differentiated by producing improved patient outcomes would, therefore, be likely to win market share. In this perspective article, the current and potential opportunities for the successful delivery and differentiation of new inhaled drug products are discussed.

Patient considerations in the treatment of COPD: focus on the new combination inhaler umeclidinium/vilanterol

Medication adherence among patients with chronic diseases, such as COPD, may be suboptimal, and many factors contribute to this poor adherence. One major factor is the frequency of medication dosing. Once-daily dosing has been shown to be an important variable in medication adherence in chronic diseases, such as COPD. New inhalers that only require once-daily dosing are becoming more widely available. Combination once-daily inhalers that combine any two of the following three agents are now available: 1) a long-acting muscarinic antagonist; 2) a long acting beta2 agonist; and 3) an inhaled corticosteroid. A new once-daily inhaler with both a long-acting muscarinic antagonist, umeclidinium bromide, and a long acting beta2 agonist, vilanterol trifenatate, is now available worldwide for COPD treatment. It provides COPD patients convenience, efficacy, and a very favorable adverse-effects profile. Additional once-daily combination inhalers are available or will soon be available for COPD patients worldwide. The use of once-daily combination inhalers will likely become the standard maintenance management approach in the treatment of COPD because they improve medication adherence.

Enhancing the buccal mucosal delivery of peptide and protein therapeutics

With continuing advances in biotechnology and genetic engineering, there has been a dramatic increase in the availability of new biomacromolecules, such as peptides and proteins that have the potential to ameliorate the symptoms of many poorly-treated diseases. Although most of these macromolecular therapeutics exhibit high potency, their large molecular mass, susceptibility to enzymatic degradation, immunogenicity and tendency to undergo aggregation, adsorption, and denaturation have limited their ability to be administered via the traditional oral route. As a result, alternative noninvasive routes have been investigated for the systemic delivery of these macromolecules, one of which is the buccal mucosa. The buccal mucosa offers a number of advantages over the oral route, making it attractive for the delivery of peptides and proteins. However, the buccal mucosa still exhibits some permeability-limiting properties, and therefore various methods have been explored to enhance the delivery of macromolecules via this route, including the use of chemical penetration enhancers, physical methods, particulate systems and mucoadhesive formulations. The incorporation of anti-aggregating agents in buccal formulations also appears to show promise in other mucosal delivery systems, but has not yet been considered for buccal mucosal drug delivery. This review provides an update on recent approaches that have shown promise in enhancing the buccal mucosal transport of macromolecules, with a major focus on proteins and peptides.

NEXThaler, an innovative dry powder inhaler delivering an extrafine fixed combination of beclometasone and formoterol to treat large and small airways in asthma

INTRODUCTION

Airway inflammation and remodelling in asthma occur in the large airways and also in the small airways. The small airways are those < 2 mm in diameter and are significant sites of chronic asthmatic inflammation. It is important, therefore, to target the small as well as the large airways in any strategy for effective treatment of this disease.

AREAS COVERED

The present review deals with the recently developed fixed dose drug combination of beclometasone dipropionate/formoterol fumarate that emits extrafine particles when delivered from an innovative dry powder inhaler (DPI), NEXThaler®. The aim is to present the technical and clinical aspects of aerosolized drug delivery to the lungs.

EXPERT OPINION

The data show that the NEXThaler DPI is an efficient device for the management of persistent asthma. The evaluation of the inhalation profiles through the NEXThaler DPI demonstrates that device activation and consistent dose delivery occurs at patient achievable inhalation flow rates, and supports the broad utility of the NEXThaler DPI in patients with asthma. Overall, all the effectiveness, efficiency and satisfaction outcomes demonstrate the NEXThaler DPI is easy to use.

New inhaler devices - the good, the bad and the ugly

Drug delivery to the lungs is an effective way of targeting inhaled therapeutic aerosols and treating obstructive airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD). In the past 10 years, several new drugs for the management of asthma and COPD have been marketed and more are under development. These new therapeutic respiratory drugs have been furthered by innovations in all categories of pulmonary drug delivery systems to ensure optimal aerosolisation performance, consistency in efficacy and satisfactory patient adherence. In this review, we discuss the technological advances and innovations in recent inhaler devices and the evolving roles of pressurised metered-dose inhalers, dry powder inhalers and nebulisers, as well as their impact on patient adherence to treatment.

Guidance on handheld inhalers in asthma and COPD guidelines

BACKGROUND

Inhaled therapy is the cornerstone of pharmacotherapy in patients with asthma and chronic obstructive pulmonary disease (COPD). Appropriate inhalation device selection is as important as drug choice but device-specific guidance appears to be lacking.

METHODS

To quantify the level of inhalation-device recommendations in clinical guidelines, a review was conducted by hand-searching national and international asthma and COPD guidelines (Global Initiative for Asthma [GINA] and Global initiative for chronic Obstructive Lung Disease [GOLD] guidelines) and an international guideline on device selection (the American College of Chest Physicians/American College of Asthma, Allergy, and Immunology [ACCP/ACAAI]). For each guideline, the number of pages, tables/figures and references relating to inhalation devices was identified.

RESULTS

GINA and GOLD guidelines contain very little inhalation device-specific guidance beyond recommendations for demonstrating and testing correct inhalation technique: <2% of pages or references and <3% of tables/figures are dedicated to devices. Device-related content in the ACCP/ACAAI device selection guideline was considerably higher with 54% of pages, 88% of tables/figures and 82% of references, respectively. Results in national guidelines reflect those on international guidelines.

CONCLUSIONS

These results indicate that there is a considerable lack of clear and specific guidance regarding inhalation devices in current asthma/COPD guidelines. More robust studies on the impact of inhalation devices are needed to increase the number of evidence statements and recommendations regarding inhalation devices.