Back to the future: inhaled drug products

Parenteral, Non-Intravenous Analgesia in Acute Traumatic Pain-A Narrative Review Based on a Systematic Literature Search

Traumatic pain is frequently encountered in emergency care and requires immediate analgesia. Unfortunately, most trauma patients report sustained pain upon arrival at and discharge from the Emergency Department. Obtaining intravenous access to administer analgesics can be time-consuming, leading to treatment delay. This review provides an overview of analgesics with both fast onset and parenteral, non-intravenous routes of administration, and also indicates areas where more research is required.

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.

Development of a Novel Bronchodilator Vaping Drug Delivery System Based on Thermal Degradation Properties

This work aims to investigate bronchodilator delivery with the use of different vaping drug delivery systems (VDDS) by determining the dose equivalence delivered in relation to different references: a clinical jet nebulizer, a pMDI (pressurized metered dose inhaler) and a DPI (dry powder inhaler). Three different bronchodilators were used (terbutaline, salbutamol hemisulfate, ipratropium bromide). The e-liquids contained the active pharmaceutical ingredient (API) in powder form. Two different VDDS were tested (JUUL and a GS AIR 2 atomizer paired with a variable lithium-ion battery (i-stick TC 40 W), 1.5 ohm resistance, and 15 W power). Samples were collected using a glass twin impinger (GTI). High-performance liquid chromatography (HPLC) was used to quantify the drugs. A next-generation impactor (NGI) was used to measure the particle size distribution. Terbutaline emerged as the optimal API for bronchodilator delivery in both VDDS devices. It achieved the delivery of a respirable dose of 20.05 ± 4.2 µg/puff for GS AIR 2 and 2.98 ± 0.52 µg/puff for JUUL. With these delivered doses, it is possible to achieve a dose equivalence similar to that of a jet nebulizer and DPI, all while maintaining a reasonable duration, particularly with the GS AIR 2. This study is the first to provide evidence that vaping bronchodilators work only with appropriate formulation, vaping technology, and specific drugs, depending on their thermal degradation properties.

Nebulized inhalation of LPAE-HDAC10 inhibits acetylation-mediated ROS/NF-κB pathway for silicosis treatment

Silicosis is a serious silica-induced respiratory disease for which there is currently no effective treatment. Irreversible pulmonary fibrosis caused by persistent inflammation is the main feature of silicosis. As an underlying mechanism, acetylation regulated by histone deacetylases (HDACs) are believed to be closely associated with persistent inflammation and pulmonary fibrosis. However, details of the mechanisms associated with the regulation of acetylated modification in silicosis have yet to be sufficiently established. Furthermore, studies on the efficient delivery of DNA to lung tissues by nebulized inhalation for the treatment of silicosis are limited. In this study, we established a mouse model of silicosis successfully. Differentially expressed genes (DEGs) between the lung tissues of silicosis and control mice were identified based on transcriptomic analysis, and HDAC10 was the only DEG among the HDACs. Acetylomic and combined acetylomic/proteomic analysis were performed and found that the differentially expressed acetylated proteins have diverse biological functions, among which 12 proteins were identified as the main targets of HDAC10. Subsequently, HDAC10 expression levels were confirmed to increase following nebulized inhalation of linear poly(β-amino ester) (LPAE)-HDAC10 nanocomplexes. The levels of oxidative stress, the phosphorylation of IKKβ, IκBα and p65, as well as inflammation were inhibited by HDAC10. Pulmonary fibrosis, and lung function in silicosis showed significant improvements in response to the upregulation of HDAC10. Similar results were obtained for the silica-treated macrophages in vitro. In conclusion, HDAC10 was identified as the main mediator of acetylation in silicosis. Nebulized inhalation of LPAE-HDAC10 nanocomplexes was confirmed to be a promising treatment option for silicosis. The ROS/NF-κB pathway was identified as an essential signaling pathway through which HDAC10 attenuates oxidative stress, inflammation, and pulmonary fibrosis in silicosis. This study provides a new theoretical basis for the treatment of silicosis.

Inhalation Dosage Forms: A Focus on Dry Powder Inhalers and Their Advancements

In this review, an extensive analysis of dry powder inhalers (DPIs) is offered, focusing on their characteristics, formulation, stability, and manufacturing. The advantages of pulmonary delivery were investigated, as well as the significance of the particle size in drug deposition. The preparation of DPI formulations was also comprehensively explored, including physico-chemical characterization of powders, powder processing techniques, and formulation considerations. In addition to manufacturing procedures, testing methods were also discussed, providing insights into the development and evaluation of DPI formulations. This review also explores the design basics and critical attributes specific to DPIs, highlighting the significance of their optimization to achieve an effective inhalation therapy. Additionally, the morphology and stability of 3 DPI capsules (Spiriva, Braltus, and Onbrez) were investigated, offering valuable insights into the properties of these formulations. Altogether, these findings contribute to a deeper understanding of DPIs and their development, performance, and optimization of inhalation dosage forms.

Preparation and characterization of lysozyme loaded liposomal dry powder inhalation using non-ionic surfactants

Delivering protein drugs through dry powder inhalation (DPI) remains a significant challenge. Liposomes offer a promising solution, providing protection for proteins from external environment and controlled release capabilities. Furthermore, the use of non-ionic surfactants plays a crucial role in protecting the activity of proteins because of how the surfactants positioning themselves at the liquid-gas interface during the spray-drying process. In this study, lysozyme-loaded liposomal DPI formulations were prepared using various non-ionic surfactants, including polysorbate 80, poloxamer 188, poloxamer 407, and sucrose stearate. Lysozyme solution and 1,2-distearoyl-sn-glycero-3-phosphatidylcholine liposomes were subjected through high-pressure homogenization to form lysozyme-loaded liposomes. Formulations of homogenized lysozyme liposomes were spray-dried and further characterized. The particle size of reconstituted liposomal lysozyme DPI was from 129.5 to 816.9 nm. The formulations showed encapsulation efficiency up to 32.5% with zeta potential value of around - 30 mV, and spherical structures were observed. The aerosol dispersion performance of the dry powder inhalers was evaluated with emitted doses reaching up to 103% and fine particle fractions up to 28.4%. Significantly higher lysozyme activity was confirmed in formulation with drug to PS 80 ratio of 1: 0.5 w/w (92.1%) compared to that of formulation containing no surfactant (59.8%). The formulation stood out as the only formulation that maintained protein activity while demonstrating good aerosol performance.

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.

HPLC-UV/VIS for Determination of Ipratropium Bromide Mixed with Salbuterol, Beclomethasone Propionate and Budesonide using Dual Wavelength-Detection Method

BACKGROUND

Inhalation preparation involves liquid or solid raw materials for delivering to lungs as aerosol or vapor. The liquid preparation for nebulizer is effective for convenient use and patient compliance and it has been extensively used in the treatment of clinical lung diseases. Clinical staff often mixes the compound ipratropium bromide with beclomethasone propionate and budesonide inhaler but reference values of inhalants for clinical use need to be established for simplifying the operation procedure. The high-performance liquid chromatography (HPLC) method of compound ipratropium bromide solution, beclomethasone propionate suspension and budesonide suspension after mixed atomization was studied.

METHODS

The specificity, linearity, recovery (accuracy), precision and stability of compound ipratropium bromide, beclomethasone propionate and budesonide were tested to verify the developed liquid phase method.

RESULTS

The developed liquid phase method had high specificity, linear R2≥0,999, recovery (accuracy) RSD (relative standard deviation) less than 2%, precision RSD less than 2,0%, and stability RSD less than 2,0%.

CONCLUSION

The liquid phase methodology developed in this study can be used for the determination of compound ipratropium bromide mixed with beclomethasone propionate and budesonide. The current methodology can also be used to provide a reference for the determination of its content after mixing, and further data support for its clinical medication.

Antivirals and the Potential Benefits of Orally Inhaled Drug Administration in COVID-19 Treatment

Coronavirus Disease 2019 (COVID-19) pandemic has been on the agenda of humanity for more than 2 years. In the meantime, the pandemic has caused economic shutdowns, halt of daily lives and global mobility, overcrowding of the healthcare systems, panic, and worse, more than 6 million deaths. Today, there is still no specific therapy for COVID-19. Research focuses on repurposing of antiviral drugs that are licensed or currently in the research phase, with a known systemic safety profile. However, local safety profile should also be evaluated depending on the new indication, administration route and dosage form. Additionally, various vaccines have been developed. But the causative virus, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), has undergone multiple variations, too. The premise that vaccines may suffice to eradicate new and all variants is unreliable, as they are based on earlier versions of the virus. Therefore, a specific medication therapy for COVID-19 is crucial and needed in order to prevent severe complications of the disease. Even though there is no specific drug that inhibits the replication of the disease-causing virus, among the current treatment options, systemic antivirals are the most medically appropriate. As SARS-CoV-2 directly targets the lungs and initiates lung damage, treating COVID-19 with inhalants can offer many advantages over the enteral/parenteral administration. Inhaled drug delivery provides higher drug concentration, specifically in the pulmonary system. This enables the reduction of systemic side effects and produces a rapid clinical response. In this article, the most frequently (systemically) used antiviral compounds are reviewed including Remdesivir, Favipiravir, Molnupiravir, Lopinavir-Ritonavir, Umifenovir, Chloroquine, Hydroxychloroquine and Heparin. A comprehensive literature search was conducted to provide insight into the potential inhaled use of these antiviral drugs and the current studies on inhalation therapy for COVID-19 was presented. A brief evaluation was also made on the use of inhaler devices in the treatment of COVID-19. Inhaled antivirals paired with suitable inhaler devices should be considered for COVID-19 treatment options.

A technology evaluation of CVT-301 (Inbrija): an inhalable therapy for treatment of Parkinson's disease

Introduction: The most widely used pharmacological treatment for Parkinson's disease is levodopa, the precursor for dopamine formation in the brain. Over time, the effectiveness of levodopa declines, and patients experience motor fluctuations, or OFF periods. A levodopa formulation administered via a capsule-based oral inhaler provides a new delivery mechanism for levodopa that provides rapid relief of OFF periods.Areas covered: CVT-301 is a dry powder formulation designed to supply levodopa to the systemic circulation via pulmonary absorption. The technology, pharmacokinetics, efficacy, and safety data of this formulation are presented.Expert opinion: Oral inhalation is a novel method of administration for levodopa that bypasses the gastrointestinal tract, allowing levodopa to enter the systemic circulation rapidly and more reliably than oral medications. Gastrointestinal dysfunction, a common feature of Parkinson's disease, can lead to impaired absorption of oral medications. Pulmonary delivery rapidly elevates levodopa plasma concentrations to provide relief of OFF periods for patients receiving oral levodopa.

Inhalation Delivery for the Treatment and Prevention of COVID-19 Infection

Coronavirus disease-2019 (COVID-19) is caused by coronavirus-2 (SARS-CoV-2) and has produced a global pandemic. As of 22 June 2021, 178 million people have been affected worldwide, and 3.87 million people have died from COVID-19. According to the Centers for Disease Control and Prevention (CDC) of the United States, COVID-19 virus is primarily transmitted between people through respiratory droplets and contact routes. Since the location of initial infection and disease progression is primarily through the lungs, the inhalation delivery of drugs directly to the lungs may be the most appropriate route of administration for treating COVID-19. This review article aims to present possible inhalation therapeutics and vaccines for the treatment of COVID-19 symptoms. This review covers the comparison between SARS-CoV-2 and other coronaviruses such as SARS-CoV/MERS, inhalation therapeutics for the treatment of COVID-19 symptoms, and vaccines for preventing infection, as well as the current clinical status of inhaled therapeutics and vaccines.

Inhaled antibodies: Quality and performance considerations

The use of antibodies in the treatment of lung diseases is of increasing interest especially as the search for COVID-19 therapies has unfolded. Historically, the use of antibody therapy was based on multiple targets including receptors involved in local hyper-reactivity in asthma, viruses and micro-organisms involved in a variety of pulmonary infectious disease. Generally, protein therapeutics pose challenges with respect to formulation and delivery to retain activity and assure therapy. The specificity of antibodies amplifies the need for attention to molecular integrity not only in formulation but also during aerosol delivery for pulmonary administration. Drug product development can be viewed from considerations of route of administration, dosage form, quality, and performance measures. Nebulizers and dry powder inhalers have been used to deliver protein therapeutics and each has its advantages that should be matched to the needs of the drug and the disease. This review offers insight into quality and performance barriers and the opportunities that arise from meeting them effectively.

Spray-Dried Inhalable Powder Formulations of Therapeutic Proteins and Peptides

Respiratory diseases are among the leading causes of morbidity and mortality worldwide. Innovations in biochemical engineering and understanding of the pathophysiology of respiratory diseases resulted in the development of many therapeutic proteins and peptide drugs with high specificity and potency. Currently, protein and peptide drugs are mostly administered by injections due to their large molecular size, poor oral absorption, and labile physicochemical properties. However, parenteral administration has several limitations such as frequent dosing due to the short half-life of protein and peptide in blood, pain on administration, sterility requirement, and poor patient compliance. Among various noninvasive routes of administrations, the pulmonary route has received a great deal of attention and is a better alternative to deliver protein and peptide drugs for treating respiratory diseases and systemic diseases. Among the various aerosol dosage forms, dry powder inhaler (DPI) systems appear to be promising for inhalation delivery of proteins and peptides due to their improved stability in solid state. This review focuses on the development of DPI formulations of protein and peptide drugs using advanced spray drying. An overview of the challenges in maintaining protein stability during the drying process and stabilizing excipients used in spray drying of proteins and peptide drugs is discussed. Finally, a summary of spray-dried DPI formulations of protein and peptide drugs, their characterization, various DPI devices used to deliver protein and peptide drugs, and current clinical status are discussed.

Report on biopharmaceutical profile of recent biotherapeutics and insilco docking studies on target bindings of known aptamer biotherapeutics

Accumulated Toxicity, disease recurrence and drug resistivity problems have been observed due to the synthetic and semisynthetic therapeutic practices, which alternatively led to focus on Bio-therapeutics production than xenobiotics. Quick plasma clearance and high potency are the reasons for trending research with huge pharma market of numerous Bio-therapeutics than ever before. Researchers proved that most of the nano and micro Bio-therapeutics have multiple beneficial therapeutic effects. We have analyzed the past, and present scenario of some notable clinically approved Bio-therapeutics to identify the future formulation needs with advanced techniques. Protein-related drugs are the foremost Bio-therapeutics such as antibodies, enzymes, and short, fragmented polypeptides show aggregation properties during storage, naked peptide moieties are resisted by the polar cell membrane, and also the antidrug antibodies were reported. Even though Nucleic acid nano-bodies are excellent target binders than proteins, they had only a few minutes of half-life. Maintaining homogeneousness upon storage of Bio-therapeutics is still a significant challenge in industrial-scale formulation. Notably, plant systems are identified as most useful cost-effective hosts to produce human enzymes than animal systems without any possible viral loads. Irrespective of numerous advancements in routes of administration and additives, subcutaneous is still a golden one to achieve better dynamics. Additionally, the interactions and effective bonds made by each class of well-known aptamer biotherapeutics which are considered as future drugs were studied.

State of the Art Review of Cell Therapy in the Treatment of Lung Disease, and the Potential for Aerosol Delivery

Respiratory and pulmonary diseases are among the leading causes of death globally. Despite tremendous advancements, there are no effective pharmacological therapies capable of curing diseases such as COPD (chronic obstructive pulmonary disease), ARDS (acute respiratory distress syndrome), and COVID-19. Novel and innovative therapies such as advanced therapy medicinal products (ATMPs) are still in early development. However, they have exhibited significant potential preclinically and clinically. There are several longitudinal studies published, primarily focusing on the use of cell therapies for respiratory diseases due to their anti-inflammatory and reparative properties, thereby hinting that they have the capability of reducing mortality and improving the quality of life for patients. The primary objective of this paper is to set out a state of the art review on the use of aerosolized MSCs and their potential to treat these incurable diseases. This review will examine selected respiratory and pulmonary diseases, present an overview of the therapeutic potential of cell therapy and finally provide insight into potential routes of administration, with a focus on aerosol-mediated ATMP delivery.

Curcumin loaded zinc oxide nanoparticles for activity-enhanced antibacterial and anticancer applications

Zinc oxide nanoparticles and curcumin have been shown to be excellent antimicrobial agents and promising anticancer agents, both on their own as well as in combination. Together, they have potential as alternatives/supplements to antibiotics and traditional anticancer drugs. In this study, different morphologies of zinc oxide-grafted curcumin nanocomposites (ZNP-Cs) were synthesized and characterized using SEM, TGA, FTIR, XRD and UV-vis spectrophotometry. Antimicrobial assays were conducted against both Gram negative and Gram-positive bacterial stains. Spherical ZnO-curcumin nanoparticles (SZNP-Cs) and rod-shaped ZnO-curcumin nanoparticles showed the most promising activity against tested bacterial strains. The inhibition zones for these curcumin-loaded ZnO nanocomposites were consistently larger than their bare counterparts or pure curcumin, revealing an additve effect between the ZnO and curcumin components. The potential anticancer activity of the synthesized nanocomposites was studied on the rhabdomyosarcoma RD cell line via MTT assay, while their cytotoxic effects were tested against human embryonic kidney cells using the resazurin assay. SZNP-Cs exhibited the best balance between the two, showing the lowest toxicity against healthy cells and good anticancer activity. The results of this investigation demonstrate that the nanomatrix synthesized can act as an effective, additively-enhanced combination delivery/therapeutic agent, holding promise for anticancer therapy and other biomedical applications.

Recent advances in the development of microparticles for pulmonary administration

Pulmonary drug delivery offers several benefits for the management of various conditions over other conventional routes. Inhalation of drugs can also be useful for targeting alveolar macrophages and for maintaining a higher drug concentration in the lung tissues to improve the efficacy of drugs and shorten the duration of treatment, thereby reducing drug toxicities. Thus, such an approach is useful in the treatment of various pulmonary and nonpulmonary diseases. Newer techniques and delivery devices have been used for the formulation of inhalable microparticles. Here. we not only focus on advances in inhalation therapy and in the preparation of microparticles, but also address the clinical development and regulatory aspects of such therapies.

In vitro, ex vivo and in vivo methods of lung absorption for inhaled drugs

The assessment and prediction of lung absorption and disposition are an increasingly essential preclinical task for successful discovery and product development of inhaled drugs for both local and systemic delivery. Hence, in vitro, ex vivo and in vivo preclinical methods of lung absorption continue to evolve with several technical, methodological and analytical refinements. As in vitro lung epithelial cell monolayer models, the air-liquid interface (ALI)-cultured Calu-3 cells have most frequently been used, but the NCI-H441 and hAELVi cells have now been proposed as the first immortalized human alveolar epithelial cells capable of forming highly-restricted monolayers. The primary ALI-cultured three-dimensional (3D) human lung cell barriers have also become available; efforts to incorporate aerosol drug deposition into the in vitro lung cell models continue; and stem cell-derived lung epithelial cells and "lung-on-a-chip" technology are emerging. The ex vivo isolated perfused rat lung (IPRL) methods have increasing been used, as they enable the kinetic determination of tissue/organ-level diffusive and membrane protein-mediated absorption and competing non-absorptive loss; the assessment of "pre-epithelial" aerosol biopharmaceutical events in the lung, such as dissolution and release; and the ex vivo-to-in vivo extrapolation and prediction. Even so, in vivo small rodent-based methods have been of mainstay use, while large animal-based methods find an additional opportunity to study region-dependent lung absorption and disposition. It is also exciting that human pharmacokinetic (PK) profiles and systemic exposures for inhaled drugs/molecules may be able to be predicted from these in vivo rodent PK data following lung delivery using kinetic modeling approach with allometric scaling. Overall, the value of these preclinical assessments appears to have shifted more to their translational capability of predicting local lung and systemic exposure in humans, in addition to rationalizing optimal inhaled dosage form and delivery system for drugs/molecules in question. It is critically important therefore to make appropriate selection and timely exploitation of the best models at each stage of drug discovery and development program for efficient progress toward product approval and clinical use.

In-vitro and in-vivo respiratory deposition of a developed metered dose inhaler formulation of an anti-migraine drug

Enhancement of zolmitriptan bioavailability through development of micronized zolmitriptan pressurized metered dose inhaler (MDI) as an alternative to its traditional drug delivery systems. A reversed phase HPLC method for zolmitriptan determination was developed and evaluated. Micronized zolmitriptan MDI formulations were prepared using two different propellants. The prepared formulations were evaluated for mean shot weight, drug content, and leakage rate in addition to in-vitro deposition using next generation impactor where mass median aerodynamic diameter (MMAD), geometric standard deviation (GSD), fine particle dose, fine particle fraction (FPF), emitted dose (ED), and dispersibility were determined. The selected formulation was evaluated for in-vivo bronchial absorption in rats. The physicochemical characters of the prepared formulations were found to be dependent mainly on the vapor pressure of the used propellant. MDI formulation prepared with HFA 134a propellant was found to have the lowest MMAD (3.47 ± 0.65) with GSD of 2.3 ± 0.4. It also had the highest FPF (41.9), ED (89.26 ± 2.35) with dispersibility of 46.9%. This formulation, when applied to rats, resulted in faster Tmax (27 ± 5 min) with higher Cmax (1236 ± 116 ng/mL) and AUC(0-12) (3375 ± 482 ng/mL·h) over the oral tablet. Its relative bioavailability was 72.7% which was 1.25 times higher than the oral tablet relative bioavailability. Zolmitriptan MDI formulation was developed using micronized zolmitriptan powder without further modification or particle engineering. The developed formulation using HFA 134a propellant could be favorable alternative, with enhanced bioavailability, to zolmitriptan oral tablet for acute migraine treatment.

Comparison of Oral, Intranasal and Aerosol Administration of Amiodarone in Rats as a Model of Pulmonary Phospholipidosis

‘Foamy’ alveolar macrophages (FAM) observed in nonclinical toxicology studies during inhaled drug development may indicate drug-induced phospholipidosis, but can also derive from adaptive non-adverse mechanisms. Orally administered amiodarone is currently used as a model of pulmonary phospholipidosis and it was hypothesized that aerosol administration would produce phospholipidosis-induced FAM that could be characterized and used in comparative inhalation toxicology. Han-Wistar rats were given amiodarone via (1) intranasal administration (6.25 mg/kg) on two days, (2) aerosol administration (3 mg/kg) on two days, (3) aerosol administration (10 mg/kg) followed by three days of 30 mg/kg or (4) oral administration (100 mg/kg) for 7 days. Alveolar macrophages in bronchoalveolar lavage were evaluated by differential cell counting and high content fluorescence imaging. Histopathology and mass-spectrometry imaging (MSI) were performed on lung slices. The higher dose aerosolised amiodarone caused transient pulmonary inflammation (p < 0.05), but only oral amiodarone resulted in FAM (p < 0.001). MSI of the lungs of orally treated rats revealed a homogenous distribution of amiodarone and a putative phospholipidosis marker, di-22:6 bis-monoacylglycerol, throughout lung tissue whereas aerosol administration resulted in localization of both compounds around the airway lumen. Thus, unlike oral administration, aerosolised amiodarone failed to produce the expected FAM responses.

Non-invasive delivery strategies for biologics

Biologics now constitute a significant element of available medical treatments. Owing to their clinical and commercial success, biologics are a rapidly growing class and have become a dominant therapeutic modality. Although most of the successful biologics to date are drugs that bear a peptidic backbone, ranging from small peptides to monoclonal antibodies (~500 residues; 150 kDa), new biologic modalities, such as nucleotide-based therapeutics and viral gene therapies, are rapidly maturing towards widespread clinical use. Given the rise of peptides and proteins in the pharmaceutical landscape, tremendous research and development interest exists in developing less-invasive or non-invasive routes for the systemic delivery of biologics, including subcutaneous, transdermal, oral, inhalation, nasal and buccal routes. This Review summarizes the current status, latest updates and future prospects for such delivery of peptides, proteins and other biologics.

Is there room for further innovation in inhaled therapy for airways disease?

Inhaled medication is the cornerstone in the treatment of patients across a spectrum of respiratory diseases including asthma and chronic obstructive pulmonary disease. The benefits of inhaled therapy have long been recognised but the most important innovations have occurred over the past 60 years, beginning with the invention of the pressurised metered dose inhaler. However, despite over 230 different device and drug combinations currently being available, disease control is far from perfect. Here we look at how innovation in inhaler design may improve treatments for respiratory diseases and how new formulations may lead to treatments for diseases beyond the lungs. We look at the three main areas where innovation in inhaled therapy is most likely to occur: 1) device engineering and design; 2) chemistry and formulations; and 3) digital technology associated with inhalers. Inhaler design has improved significantly but considerable challenges still remain in order to continually innovate and improve targeted drug delivery to the lungs. Healthcare professionals want see innovations that motivate their patients to achieve their goal of improving their health, through better adherence to treatment. Patients want devices that are easy to use and to see that their efforts are rewarded by improvements in their condition.

KEY POINTS

The dictionary definition of innovation is the introduction of new things, ideas or ways of doing something. We show how this definition can be applied to inhaled therapy.We take a look at the past to see what drove innovation in inhaler design and how this has led to the current devices.We look at the current drivers of innovation in engineering, chemistry and digital technology and predict how this may translate to new devices.Can innovation help the healthcare professional manage their patients better?What does the patient expect from innovation in their device?

EDUCATIONAL AIMS

To understand the importance of inhaled medication in the treatment of lung diseases.To understand how innovation has helped advance some of the devices patients use today from basic and inefficient designs.To understand the obstacles that prevent patients from receiving optimal treatment from their inhalers.To understand how innovation in inhaler design can lead to improved treatment for patients and widen the range of diseases that can be treated via the inhaled route.

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.

The Relationship Between the Permeability and the Performance of Carrier-Based Dry Powder Inhalation Mixtures: New Insights and Practical Guidance

The permeability of a powder bed reflects its particle size distribution, shape, packing, porosity, cohesivity, and tensile strength in a manner relevant to powder fluidization. The relationship between the permeability and the performance of carrier-based dry powder inhalation (DPI) mixtures has, however, aroused controversy. The current study sought to gain new insights into the relationship and to explore its potential applications. We studied eight lactose materials as DPI carriers. The carriers covered a broad permeability range of 0.42-13.53 D and moreover differed in particle size distribution, particle shape, crystal form, and/or porosity. We evaluated the performance of inhalation mixtures of each of these carriers and fluticasone propionate after aerosolization from an Aerolizer®, a model turbulent-shear inhaler, at a flow rate of 60 L/min. Starting from the high permeability side, the inhalation mixture performance increased as the carrier permeability decreased until optimum performance was reached at permeability of ~ 3.2 D. Increased resistance to air flow strengthens aerodynamic dispersion forces. The inhalation mixture performance then decreased as the carrier permeability further decreased. Very high resistance to air flow restricts powder dispersion. The permeability accounted for effects of carrier size, shape, and macroporosity on the performance. We confirmed the relationship by analysis of two literature permeability-performance datasets, representing measurements that differ from ours in terms of carrier grades, drug, technique used to determine permeability, turbulent-shear inhaler, and/or aerosolization flow rate. Permeability provides useful information that can aid development of DPI mixtures for turbulent-shear inhalers. A practical guidance is provided.

Calcium Phosphate Particles as Pulmonary Delivery System for Interferon-α in Mice

Systemically administered interferons are rapidly cleared from the circulation thus requiring frequent dosing to maintain the therapeutic levels of circulating interferon. This is particularly problematic for their use in the treatment of chronic diseases. The purpose of this study was to evaluate the potential of proprietary calcium phosphate (CaP) particles to deliver biologically active interferon alpha (IFNα) via the lungs into systemic circulation. Recombinant human IFNα-2a was formulated with proprietary CaP particles. In vitro biological activity of IFNα was assessed for its potential to activate IFN-induced cellular pathways in HEK-Blu-IFN α/β cell cultures. Antiviral activity was evaluated against vesicular stomatitis virus (VSV) infection of HeLa cells. Male BALB/c mice were used to evaluate the absorption of IFNα from CaP-IFNα across the lungs following intratracheal (IT) instillation. Serum IFNα concentrations up to 9 h post-treatment were determined. Data were analyzed to obtain pharmacokinetic (PK) parameters. Data from these studies indicated that IFNα formulated with CaP retains its biological activity, and it is transported into circulation in a dose-dependent manner. PK analysis showed larger than two-fold area under the serum concentration-time curve (AUC) for CaP-IFNα compared to non-formulated IFNα administered IT. The IFNα formulated with CaP had two-fold longer half-life (t1/2) and mean residence time (MRT) relative to IFNα alone administered by injection. Clearance of CaP-IFNα was slower than IFNα administered IM or IT. Relative bioavailability of CaP-IFNα was 1.3-fold of IFNα injection and twofold of IFNα administered IT. Furthermore, inhalation of aerosolized CaP did not indicate any lung toxicity in animals.

Delivery of Therapeutics to the Lung

Pulmonary delivery in animal models can be performed using either direct administration methods or by passive inhalation. Direct pulmonary delivery requires the animal to be endotracheally intubated, whereas passive delivery uses a nose-only or a whole-body chamber. Endotracheal delivery of therapeutics and vaccines allows investigators to deliver the payload directly into the lung without the limitations associated with passive pulmonary administration methods. Additionally, endotracheal delivery can achieve deep lung delivery without the involvement of other exposure routes and is more reproducible and quantitative than passive pulmonary delivery in terms of accurate dosing. Here we describe the endotracheal delivery of both liquids and dry powders for preclinical models of treatment and exposure.

In Vivo Pulmonary Delivery and Magnetic-Targeting of Dry Powder Nano-in-Microparticles

This brief communication evaluates the cytotoxicity and targeting capability of a dry powder chemotherapeutic. Nano-in-microparticles (NIMs) are a dry powder drug delivery vehicle containing superparamagnetic iron oxide nanoparticles (SPIONs) and either doxorubicin (w/w solids) or fluorescent nanospheres (w/v during formulation; as a drug surrogate) in a lactose matrix. In vitro cytotoxicity was evaluated in A549 adenocarcinoma cells using MTS and LDH assays to assess viability and toxicity after 48 h of NIMs exposure. In vivo magnetic-field-dependent targeting of inhaled NIMs was evaluated in a healthy mouse model. Mice were endotracheally administered fluorescently labeled NIMs either as a dry powder or a liquid aerosol in the presence of an external magnet placed over the left lung. Quantification of fluorescence and iron showed a significant increase in both fluorescence intensity and iron content to the left magnetized lung. In comparison, we observed decreased targeting of fluorescent nanospheres to the left lung from an aerosolized liquid suspension, due to the dissociation of SPIONs and nanoparticles during pulmonary administration. We conclude that dry powder NIMs maintain the therapeutic cytotoxicity of doxorubicin and can be better targeted to specific regions of the lung in the presence of a magnetic field, compared to a liquid suspension.

Regional Ventilation Is the Main Determinant of Alveolar Deposition of Coarse Particles in the Supine Healthy Human Lung During Tidal Breathing

BACKGROUND

To quantify the relationship between regional lung ventilation and coarse aerosol deposition in the supine healthy human lung, we used oxygen-enhanced magnetic resonance imaging and planar gamma scintigraphy in seven subjects.

METHODS

Regional ventilation was measured in the supine posture in a 15 mm sagittal slice of the right lung. Deposition was measured by using planar gamma scintigraphy (coronal scans, 40 cm FOV) immediately postdeposition, 1 hour 30 minutes and 22 hours after deposition of ^99mTc-labeled particles (4.9 μm MMAD, GSD 2.5), inhaled in the supine posture (flow 0.5 L/s, 15 breaths/min). The distribution of retained particles at different times was used to infer deposition in different airway regions, with 22 hours representing alveolar deposition. The fraction of total slice ventilation per quartile of lung height from the lung apex to the dome of the diaphragm at functional residual capacity was computed, and co-registered with deposition data-apices aligned-using a transmission scan as reference. The ratio of fractional alveolar deposition to fractional ventilation of each quartile (r) was used to evaluate ventilation and deposition matching (r > 1, regional aerosol deposition fraction larger than regional ventilation fraction).

RESULTS

r was not significantly different from 1 for all regions (1.04 ± 0.25, 1.08 ± 0.22, 1.03 ± 0.17, 0.92 ± 0.13, apex to diaphragm, p > 0.40) at the alveolar level (r_22h). For retention times r_0h and r_1h30, only the diaphragmatic region at r_1h30 differed significantly from 1.

CONCLUSIONS

These results support the hypothesis that alveolar deposition is directly proportional to ventilation for ∼5 μm particles that are inhaled in the supine posture and are consistent with previous simulation predictions that show that convective flow is the main determinant of aerosol transport to the lung periphery.

Nanomaterial Drug Products: Manufacturing and Analytical Perspectives

The increasing use of nanotechnology, including nanoparticles, in the preparation of drug products requires both manufacturing and analytical considerations in order to establish the quality metrics suitable for performance and risk assessment. A range of different nanoparticle systems exists including (but not limited to) nano-drugs, nano-additives, and nano-carriers. These systems generally require more complex production and characterization strategies than conventional pharmaceutical dosage forms. The advantage of using nanoparticle systems in pharmaceutical science is that the effective and desired function of the material can be designed through modern manufacturing processes. This paper offers a systematic nomenclature which allows for greater understanding of the drug product under evaluation based on available data from other nanoparticle reports. Analytical considerations of nano-drugs, nano-additives, and nano-carriers and the way in which they are measured are directly connected to quality control. Ultimately, the objective is to consider the entire nano-drug, nano-additive, and nano-carrier product life cycle with respect to its manufacture, use, and eventual fate. The tools and approaches to address the needs of these products exist; it should be the task of the pharmaceutical scientists and those in related disciplines to increase their understanding of nanomedicine and its novel products.

Inhaled Antibiotics for Gram-Negative Respiratory Infections

Gram-negative organisms comprise a large portion of the pathogens responsible for lower respiratory tract infections, especially those that are nosocomially acquired, and the rate of antibiotic resistance among these organisms continues to rise. Systemically administered antibiotics used to treat these infections often have poor penetration into the lung parenchyma and narrow therapeutic windows between efficacy and toxicity. The use of inhaled antibiotics allows for maximization of target site concentrations and optimization of pharmacokinetic/pharmacodynamic indices while minimizing systemic exposure and toxicity. This review is a comprehensive discussion of formulation and drug delivery aspects, in vitro and microbiological considerations, pharmacokinetics, and clinical outcomes with inhaled antibiotics as they apply to disease states other than cystic fibrosis. In reviewing the literature surrounding the use of inhaled antibiotics, we also highlight the complexities related to this route of administration and the shortcomings in the available evidence. The lack of novel anti-Gram-negative antibiotics in the developmental pipeline will encourage the innovative use of our existing agents, and the inhaled route is one that deserves to be further studied and adopted in the clinical arena.

Protection from Cigarette Smoke-Induced Lung Dysfunction and Damage by H2 Relaxin (Serelaxin)

Cigarette smoke (CS) is the major etiologic factor of chronic obstructive pulmonary disease (COPD), which is characterized by airway remodeling, lung inflammation and fibrosis, emphysema, and respiratory failure. The current therapies can improve COPD management but cannot arrest its progression and reduce mortality. Hence, there is a major interest in identifying molecules susceptible of development into new drugs to prevent or reduce CS-induced lung injury. Serelaxin (RLX), or recombinant human relaxin-2, is a promising candidate because of its anti-inflammatory and antifibrotic properties highlighted in lung disease models. Here, we used a guinea pig model of CS-induced lung inflammation, and remodeling reproducing some of the hallmarks of COPD. Animals exposed chronically to CS (8 weeks) were treated with vehicle or RLX, delivered by osmotic pumps (1 or 10 μg/day) or aerosol (10 μg/ml/day) during CS treatment. Controls were nonsmoking animals. RLX maintained airway compliance to a control-like pattern, likely because of its capability to counteract lung inflammation and bronchial remodeling. In fact, treatment of CS-exposed animals with RLX reduced the inflammatory recruitment of leukocytes, accompanied by a significant reduction of the release of proinflammatory cytokines (tumor necrosis factor α and interleukin-1β). Moreover, RLX was able to counteract the adverse bronchial remodeling and emphysema induced by CS exposure by reducing goblet cell hyperplasia, smooth muscle thickening, and fibrosis. Of note, RLX delivered by aerosol has shown a comparable efficacy to systemic administration in reducing CS-induced lung dysfunction and damage. In conclusion, RLX emerges as a new molecule to counteract CS-induced inflammatory lung diseases.

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

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

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

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

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

Inhaled insulin: A "puff" than a "shot" before meals

Diabetes is a metabolic disorder characterized by relative or absolute deficiency of insulin, resulting in hyperglycemia. The main treatment of diabetes relies on subcutaneous insulin administration by injection or continuous infusion to control glucose levels, besides oral hypoglycemic agents for type 2 diabetes. Novel routes of insulin administration are an area of research in the diabetes field as insulin injection therapy is burdensome and painful for many patients. Inhalational insulin is a potential alternative to subcutaneous insulin in the management of diabetes. The large surface area, good vascularization, immense capacity for solute exchange and ultra-thinness of the alveolar epithelium facilitates systemic delivery of insulin via pulmonary administration. Inhaled insulin has been recently approved by Food and Drug Administration (FDA). It is a novel, rapid-acting inhaled insulin with a pharmacokinetic profile that is different from all other insulin products and comparatively safer than the previous failed inhaled insulin (Exubera).

A Role for Low Density Lipoprotein Receptor-Related Protein 1 in the Cellular Uptake of Tissue Plasminogen Activator in the Lungs

PURPOSE

To gain knowledge of lung clearance mechanisms of inhaled tissue plasminogen activator (tPA).

METHODS

Using an in vivo mouse model and ex vivo murine whole organ cell suspensions, we examined the capability of the lungs to utilize LRP1 receptor-mediated endocytosis (RME) for the uptake of exogenous tPA with and without an LRP1 inhibitor, receptor associated protein (RAP), and quantitatively compared it to the liver. We also used a novel imaging technique to assess the amount LRP1 in sections of mouse liver and lung.

RESULTS

Following intratracheal administration, tPA concentrations in the bronchoalveolar lavage fluid (BALF) declined over time following two-compartment pharmacokinetics suggestive of a RME clearance mechanism. Ex vivo studies showed that lung and liver cells are similarly capable of tPA uptake via LRP1 RME which was reduced by ~50% by RAP. The comparable lung and liver uptake of tPA is likely due to equivalent amounts of LRP1 of which there was an abundance in the alveolar epithelium.

CONCLUSIONS

Our findings indicate that LRP1 RME is a candidate clearance mechanism for inhaled tPA which has implications for the development of safe and effective dosing regimens of inhaled tPA for the treatment of plastic bronchitis and other fibrin-inflammatory airway diseases in which inhaled tPA may have utility.

Intranasally administered serelaxin abrogates airway remodelling and attenuates airway hyperresponsiveness in allergic airways disease

BACKGROUND

The peptide hormone relaxin plays a key role in the systemic hemodynamic and renovascular adaptive changes that occur during pregnancy, which is linked to its antiremodelling effects. Serelaxin (a recombinant form of human gene-2 relaxin) has been shown to inhibit lung fibrosis in various disease models and reverse airway remodelling and airway hyperresponsiveness (AHR) in allergic airways disease (AAD).

OBJECTIVE

Although continuous systemic delivery of exogenous serelaxin alleviates allergic fibrosis and AHR, more direct routes for administration into the lung have not been investigated. Thus, intranasal administration of serelaxin was evaluated for its ability to reverse airway remodelling and AHR associated with AAD.

METHODS

Female Balb/c mice were subjected to a 9-week model of chronic AAD. Subgroups of animals (n = 12/group) were then treated intranasally with serelaxin (0.8 mg/mL) or vehicle once daily for 14 days (from weeks 9-11). Saline-sensitized/challenged mice treated with intranasal saline served as additional controls. Differential bronchoalveolar lavage (BAL) cell counts, ovalbumin (OVA)-specific IgE levels, tissue inflammation, parameters of airway remodelling and AHR were then assessed.

RESULTS

Chronic AAD was associated with significant increases in differential BAL cell counts, OVA-specific IgE levels, inflammation, epithelial thickening, goblet cell metaplasia, TGF-β1 expression, epithelial Smad2 phosphorylation (pSmad2), subepithelial collagen thickness, total lung collagen concentration and AHR (all P < 0.05 vs. respective measurements from saline-treated mice). Daily intranasal delivery of serelaxin significantly diminished AAD-induced epithelial thickening, epithelial pSmad2, subepithelial and total lung collagen content (fibrosis) and AHR (all P < 0.05 vs. vehicle-treated AAD mice).

CONCLUSIONS AND CLINICAL RELEVANCE

Intranasal delivery of serelaxin can effectively reduce airway remodelling and AHR, when administered once daily. Respirable preparations of serelaxin may have therapeutic potential for the prevention and/or reversal of established airway remodelling and AHR in asthma.

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.

Developing aerosol vaccines for Mycobacterium tuberculosis: Workshop proceedings: National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, USA, April 9, 2014

On April 9, 2014, Aeras and the National Institute of Allergy and Infectious Diseases convened a workshop entitled "Developing Aerosol Vaccines for Mycobacterium tuberculosis" in Bethesda, MD. The purpose of the meeting was to explore the potential for developing aerosol vaccines capable of preventing infection with M. tuberculosis (Mtb), preventing the development of active tuberculosis (TB) among those latently infected with Mtb, or as immunotherapy for persons with active TB. The workshop was organized around four key questions relevant to developing and assessing aerosol TB vaccines: (1) What is the current knowledge about lung immune responses and early pathogenesis resulting after Mtb infection and what are the implications for aerosol TB vaccine strategies? (2) What are the technical issues surrounding aerosol vaccine delivery? (3) What is the current experience in aerosol TB vaccine development? and (4) What are the regulatory implications of developing aerosol vaccines, including those for TB? Lessons learned from the WHO effort to develop an aerosol measles vaccine served as a case example for overall discussions at the meeting. Workshop participants agreed that aerosol delivery represents a potentially important strategy in advancing TB vaccine development efforts. As no major regulatory, manufacturing or clinical impediments were identified, members of the workshop emphasized the need for greater support to further explore the potential for this delivery methodology, either alone or as an adjunct to traditional parenteral methods of vaccine administration.