Variability in delivered dose and respirable delivered dose from nebulizers: are current regulatory testing guidelines sufficient to produce meaningful information?

Comparison of the Application of Vibrating Mesh Nebulizer and Jet Nebulizer in Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-analysis

Objective

To comparison of the application of Vibrating Mesh Nebulizer and Jet Nebulizer in chronic obstructive pulmonary disease (COPD).

Research Methods

This systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) statements. The primary outcome measures analyzed included: The amount of inhaler in the urine sample at 30 minutes after inhalation therapy (USAL0.5), The total amount of inhaler in urine sample within 24 hours (USAL24), Aerosol emitted, Forced expiratory volume in 1 second (FEV1), Forced vital capacity (FVC).

Results

Ten studies were included with a total of 314 study participants, including 157 subjects in the VMN group and 157 subjects in the JN group. The data analysis results of USAL0.5, MD (1.88 [95% CI, 0.95 to 2.81], P = 0.000), showed a statistically significant difference. USAL24, MD (1.61 [95% CI, 1.14 to 2.09], P = 0.000), showed a statistically significant difference. The results of aerosol emitted showed a statistically significant difference in MD (3.44 [95% CI, 2.84 to 4.04], P = 0.000). The results of FEV1 showed MD (0.05 [95% CI, -0.24 to 0.35], P=0.716), the results were not statistically significant. The results of FVC showed MD (0.11 [95% CI, -0.18 to 0.41], P=0.459), the results were not statistically significant. It suggests that VMN is better than JN and provides higher aerosols, but there is no difference in improving lung function between them.

Conclusion

VMN is significantly better than JN in terms of drug delivery and utilization in the treatment of patients with COPD. However, in the future use of nebulizers, it is important to select a matching nebulizer based on a combination of factors such as mechanism of action of the nebulizer, disease type and comorbidities, ventilation strategies and modes, drug formulations, as well as cost-effectiveness, in order to achieve the ideal treatment of COPD.

Evaluation of antibody drug delivery efficiency via nebulizer in various airway models and breathing patterns

BACKGROUND

Nebulizers are commonly used to treat respiratory diseases, which are a major cause of morbidity and mortality. While inhalation therapy with antibodies has been evaluated in preclinical studies and clinical trials for respiratory diseases, it has not yet been approved for treatment. Moreover, there is limited information regarding the delivery efficiency of therapeutic antibodies via nebulizer.

METHODS

In this study, the nebulization characteristics and drug delivery efficiencies were compared when immunoglobulin G (IgG) was delivered by five nebulizers using two airway models and five breathing patterns. The study confirmed that the delivered dose and drug delivery efficiency were reduced in the child model compared to those in the adult model and in the asthma pattern compared to those in the normal breathing pattern.

RESULTS

The NE-SM1 NEPLUS vibrating mesh nebulizer demonstrated the highest delivery efficiency when calculated as a percentage of the loading dose, whereas the PARI BOY SX + LC SPRINT (breath-enhanced) jet nebulizer had the highest delivery efficiency when calculated as a percentage of the emitted dose.

CONCLUSION

The results suggest that the total inspiration volume, output rate, and particle size should be considered when IgG nebulization is used. We, therefore, propose a method for evaluating the efficiency of nebulizer for predicting antibody drug delivery.

Nebulizers effectiveness on pulmonary delivery of alpha-1 antitrypsin

The nebulization of alpha-1 antitrypsin (AAT) for its administration to the lung could be an interesting alternative to parenteral infusion for patients suffering from AAT genetic deficiency (AATD). In the case of protein therapeutics, the effect of the nebulization mode and rate on protein conformation and activity must be carefully considered. In this paper two types of nebulizers, i.e., a jet and a mesh vibrating system, were used to nebulize a commercial preparation of AAT for infusion and compared. The aerosolization performance, in terms of mass distribution, respirable fraction, and drug delivery efficiency, as well as the activity and aggregation state of AAT upon in vitro nebulization were investigated. The two nebulizers demonstrated equivalent aerosolization performances, but the mesh nebulizer provided a higher efficiency in the delivery of the dose. The activity of the protein was acceptably preserved by both nebulizers and no aggregation or changes in its conformation were identified. This suggests that nebulization of AAT represents a suitable administration strategy ready to be translated to the clinical practice for delivering the protein directly to the lungs in AATD patients, either as a support therapy to parenteral administration or for subjects with a precocious diagnosis, to prevent the onset of pulmonary symptoms.

Good Practices for the Laboratory Performance Testing of Aqueous Oral Inhaled Products (OIPs): an Assessment from the International Pharmaceutical Aerosol Consortium on Regulation and Science (IPAC-RS)

Multiple sources must be consulted to determine the most appropriate procedures for the laboratory-based performance evaluation of aqueous oral inhaled products (OIPs) for the primary measures, dose uniformity/delivery, and aerodynamic particle (droplet) size distribution (APSD). These sources have been developed at different times, mainly in Europe and North America, during the past 25 years by diverse organizations, including pharmacopeial chapter/monograph development committees, regulatory agencies, and national and international standards bodies. As a result, there is a lack of consistency across all the recommendations, with the potential to cause confusion to those developing performance test methods. We have reviewed key methodological aspects of source guidance documents identified by a survey of the pertinent literature and evaluated the underlying evidence supporting their recommendations for the evaluation of these performance measures. We have also subsequently developed a consistent series of solutions to guide those faced with the various associated challenges when developing OIP performance testing methods for oral aqueous inhaled products.

Not all nebulizers are created equal: Considerations in choosing a nebulizer for aerosol delivery during mechanical ventilation

INTRODUCTION

Aerosol therapy is commonly prescribed in the mechanically ventilated patient. Jet nebulizers (JN) and vibrating mesh nebulizers (VMN) are the most common nebulizer types, however, despite VMN's well established superior performance, JN use remains the most commonly used of the two. In this review, we describe the key differentiators between nebulizer types and how considered selection of nebulizer type may enable successful therapy and the optimization of drug/device combination products.

AREAS COVERED

Following a review of the published literature up to February 2023, the current state of the art in relation to JN and VMN is discussed under the headings of in vitro performance of nebulizers during mechanical ventilation, respective compatibility with formulations for inhalation, clinical trials making use of VMN during mechanical ventilation, distribution of nebulized aerosol throughout the lung, measuring the respective performance of nebulizers in the patient and non-drug delivery considerations in nebulizer choice.

EXPERT OPINION

Whether for standard care, or the development of drug/device combination products, the choice of nebulizer type should not be made without consideration of the unique needs of the combination of each of drug, disease and patient types, as well as target site for deposition, and healthcare professional and patient safety.

Bronchodilator response after two methods of salbutamol nebulization in asthmatic children

Introduction

Salbutamol is used in bronchodilator response testing (BDRT), which is an important diagnostic tool in bronchial obstructive diseases. Most available studies compare the bronchodilator response of salbutamol administered with a pressurized metered-dose inhaler and salbutamol in a nebulization solution.

Aim

The spirometric evaluation of the bronchodilator response of two methods of salbutamol nebulization in asthmatic children.

Material and methods

A randomized, open, comparative study was conducted in which 132 children with partially controlled asthma and current bronchial obstruction determined by spirometry were enrolled. BDRT was conducted using salbutamol solution administered with either a continuous jet nebulizer (CON) or a breath-actuated jet nebulizer (BAN). The BAN group received half the dose of the drug compared to the CON group, i.e. 2.5 mg. Changes in FEV₁ and FEF25-75 after drug administration were calculated in relation to the baseline values.

Results

The change in FEV₁ after salbutamol administration was 16.9 ±9.7% in the BAN group and was statistically significantly higher than in the CON group (12.6 ±8.8%) (p = 0.026). The change in FEF25-75 was 37.7 ±23.2% in the BAN group and 32.7 ±25.5% in the CON group (p = 0.061). There were no statistically significant differences in the frequency of adverse events between the compared groups.

Conclusions

Salbutamol inhaled from BAN results in a better bronchodilator response than twice the nominal dose of this drug inhaled from CON, which is due to the absence of drug loss during the expiratory phase and therefore greater pulmonary deposition.

Reconciling Oxygen and Aerosol Delivery with a Hood on In Vitro Infant and Paediatric Models

This study aimed to evaluate optimal aerosol and oxygen delivery with a hood on an infant model and a paediatric model. A facemask and a hood with three inlets, with or without a front cover, were used. A small-volume nebuliser with a unit-dose of salbutamol was used for drug delivery and an air entrainment nebuliser was used to deliver oxygen at 35%. Infant and paediatric breathing patterns were mimicked; a bacterial filter was connected to the end of a manikin trachea for aerosol drug collection, and an oxygen analyser was used to measure the oxygen concentration. For the infant model, inhaled drug dose was significantly higher when the nebuliser was placed in the back of the hood and with a front cover. This was verified by complementary computational simulations in a comparable infant-hood model. For the paediatric model, the inhaled dose was greater with a facemask than with a hood. Oxygen delivery with a facemask and a hood with a front cover achieved a set concentration in both models, yet a hood without a front cover delivered oxygen at far lower concentrations than the set concentration.

Methacholine challenges: comparison of different tidal breathing challenge methods

Tidal-breathing methacholine challenges are now recommended by guidelines, to avoid the bronchoprotective effects of deep inhalation. This study compared different tidal breathing methacholine challenge methods; assessed the agreement between tidal dosimetric and continuous output challenges; and assessed challenge repeatability with different methods.

15 asthma patients performed dosimetric challenges and a continuous-output breath-actuated challenge, all ≥3 days apart. All subjects had a pre-bronchodilator forced expiratory volume in 1 s (FEV₁) ≥65% predicted, and a cumulative dose causing a 20% reduction in FEV₁ (PD₂₀) <1.2 mg.

Of the dosimetric challenges, one method increased methacholine concentration (standard dosimetric challenge), and one adjusted nebuliser output time to increase dose (adjusted dosimetric challenge). The adjusted dosimetric and continuous output challenges were performed twice on separate days to assess for repeatability. All challenges were matched for dose at each dose step. The mean PD₂₀ ratio of the standard dosimetric challenge to the adjusted dosimetric challenge was 0.90 (95% CI 0.66–1.23, p=0.49) and intraclass correlation coefficient (ICC) was 0.82. Repeated adjusted dosimetric challenges had an ICC 0.62 for PD₂₀. Repeated continuous output challenges had an ICC 0.74 for PD₂₀. The adjusted dosimetric and continuous output challenges correlated (r=0.69, p=0.0043; ICC 0.65), but PD₂₀ was higher for the adjusted dosimetric challenge (mean PD₂₀ ratio 2.31, 95% CI 1.57–3.40; p=0.0004).

Tidal dosimetric methacholine challenge using adjustment of nebuliser output produces results with good repeatability. The results of this adjusted dosimetric method differed from the continuous output method, underscoring that the results of different methacholine challenge methodologies may not be directly comparable.

Tidal breathing challenges are now the preferred method to administer a methacholine challenge. This study reports a tidal dosimetric methacholine challenge method that adjusts nebuliser output, which can be used to obtain results with good repeatability.https://bit.ly/3fX0F3f

In vitro delivery efficiencies of nebulizers for different breathing patterns

BACKGROUND

Nebulizers are medical devices that deliver aerosolized medication directly to lungs to treat a variety of respiratory diseases. However, breathing patterns, respiration rates, airway diameters, and amounts of drugs delivered by nebulizers may be respiratory disease dependent.

METHOD

In this study, we developed a respiratory simulator consisting of an airway model, an artificial lung, a flow sensor, and an aerosol collecting filter. Various breathing patterns were generated using a linear actuator and an air cylinder. We tested six home nebulizers (jet (2), static (2), and vibrating mesh nebulizers (2)). Nebulizers were evaluated under two conditions, that is, for the duration of nebulization and at a constant output 1.3 mL using four breathing patterns, namely, the breathing pattern specified in ISO 27427:2013, normal adult, asthmatic, and COPD.

RESULTS

One of the vibrating mesh nebulizers had the highest dose delivery efficiency. The drug delivery efficiencies of nebulizers were found to depend on breathing patterns.

CONCLUSION

We suggest a quantitative drug delivery efficiency evaluation method and calculation parameters that include considerations of constant outputs and residual volumes. The study shows output rates and breathing patterns should be considered when the drug delivery efficiencies of nebulizers are evaluated.

Aerosolization Performance of Jet Nebulizers and Biopharmaceutical Aspects

In this work, 13 jet nebulizers, some of which in different configurations, were investigated in order to identify the biopharmaceutical constraints related to the quality attributes of the medicinal products, which affect their safety, efficiency, compliance, and effectiveness. The aerosolization parameters, including the aerosol output, aerosol output rate, mass median aerodynamic diameter, and fine particle fraction, were determined according to the European Standard EN 13544-1, using sodium fluoride as a reference formulation. A comparison between the aerosol output nebulization time and the fine particle fraction displayed a correlation between the aerosol quality and the nebulization rate. Indeed, the quality of the nebulization significantly increased when the rate of aerosol emission was reduced. Moreover, the performance of the nebulizers was analyzed in terms of respirable delivered dose and respirable dose delivery rate, which characterize nebulization as the rate and amount of respirable product that could be deposited into the lungs. Depending on which of these two latter parameters was used, the nebulizers showed different performances. The differences, in terms of the rate and amount of delivered aerosol, could provide relevant information for the appropriate choice of nebulizer as a function of drug product, therapy, and patient characteristics.

Subunit-based mucosal vaccine delivery systems for pulmonary delivery - Are they feasible?

Pulmonary infections are the most common cause of death globally. However, the development of mucosal vaccines that provide protective immunity against respiratory pathogens are limited. In contrast to needle-based vaccines, efficient vaccines that are delivered via noninvasive mucosal routes (such as via the lungs and nasal passage) produce both antigen-specific local mucosal IgA and systemic IgG protective antibodies. One major challenge in the development of pulmonary vaccines using subunit antigens however, is the production of optimal immune responses. Subunit vaccines therefore rely upon use of adjuvants to potentiate immune responses. While the lack of suitable mucosal adjuvants has hindered progress in the development of efficient pulmonary vaccines, particle-based systems can provide an alternative approach for the safe and efficient delivery of subunit vaccines. In particular, the rational engineering of particulate vaccines with optimal physicochemical characteristics can produce long-term protective immunity. These protect antigens against enzymatic degradation, target antigen presenting cells and initiate optimal humoral and cellular immunity. This review will discuss our current understanding of pulmonary immunology and developments in fabricating particle characteristics that may evoke potent and durable pulmonary immunity.