Search Results (258)

This review summarizes innovative co-formulation strategies for non-marketed dry powder inhalers (DPIs), enabling the simultaneous pulmonary delivery of multiple active pharmaceutical ingredients (APIs). Key approaches include co-amorphous systems (COAMS) and co-crystals, which combine two APIs into a single particle, improving aerodynamic properties, solubility, dissolution, and patient compliance while reducing manufacturing complexity. Core–shell microparticles, produced via spray drying, allow spatial separation and controlled release of APIs, minimizing drug–drug interactions and enabling tailored pharmacokinetics. Co-spray drying of dual APIs can yield particles with superior aerosolization and stability, though examples remain limited. Nanoparticle-based systems offer enhanced lung deposition and cellular uptake but face challenges in device compatibility, scalability, and regulatory approval. Each technology presents unique advantages and limitations regarding manufacturability, dose flexibility, and clinical translation. This review also highlights advances in in vitro toxicity testing, including air–liquid interface cultures, organoids, lung-on-chip models, and precision-cut lung slices, which are increasingly important as alternatives to animal studies. The importance of using an aerosol exposure system for the testing is highlighted. Ultimately, the choice of co-formulation platform should balance scientific innovation with practical considerations of manufacturing and regulatory requirements to maximize therapeutic benefit and commercial viability for future DPI combination products. Full article

Background and objectives: Occupational and environmental inhalation exposures, including high-aspect-ratio carbon nanotubes, can trigger pulmonary fibrosis (PF). The relationship between exposure-specific fibrogenic pathways (granulomatous inflammation versus diffuse epithelial injury) and lung microbiome dysbiosis remains incompletely understood. We therefore compared lung microbiome alterations in rat PF models induced by multi-walled carbon nanotubes (MWCNTs) and bleomycin. Materials and Methods: Female Wistar rats received a single intratracheal instillation of vehicle, MWCNTs (750 μg/rat), or bleomycin (1 mg/rat). At day 28, fibrosis and inflammation were evaluated by histopathology and bronchoalveolar lavage fluid (BALF) profiling. Lung microbial communities were characterized by 16S rRNA gene sequencing (V3–V4). Seventeen lung samples passed stringent quality control and were analyzed (control n = 5; bleomycin n = 7; MWCNT n = 5). Results: Both agents induced PF with increased profibrotic signaling, but with distinct pathological signatures: MWCNTs produced localized granulomatous lesions and a robust neutrophilic response (25% of BALF cells), whereas bleomycin caused diffuse interstitial remodeling. Bleomycin increased microbial richness (alpha diversity; p < 0.05) and significantly shifted community structure (beta diversity; p < 0.05), while MWCNT exposure showed comparatively limited changes in global diversity. The relative abundance of Pseudogracilibacillus (including P. marinus) was higher in the bleomycin group than in controls, whereas Facklamia tabacinasalis and Corynebacterium maris were more abundant in the MWCNT group. Across samples, Proteobacteria abundance was inversely correlated with BALF TGF-β, MCP-1, and neutrophil proportion. At the species level, Pseudogracilibacillus marinus was positively correlated with BALF TGF-β, while Facklamia tabacinasalis and Corynebacterium maris were positively correlated with MCP-1, CINC-3, and neutrophil proportion (Spearman; p < 0.05). Conclusions: Mechanistically distinct fibrogenic exposures generate exposure-linked lung microbiome signatures that track with host inflammatory and profibrotic responses. These signatures may support biomarker development for environmentally and occupationally relevant PF and motivate longitudinal and functional studies to clarify causality. Full article

Background: Chronic Obstructive Pulmonary Disease (COPD) is a common condition that can cause dyspnea, pain, and biomechanical-postural alterations, especially when overlapping with Myofascial Pain Syndrome (MPS). Balneological rehabilitation medicine can help manage COPD and MPS, but it lacks homogeneity and detailed descriptions of effective therapeutic protocols. Therefore, we conducted a case series to preliminarily evaluate the clinical effects of a detailed and codified approach, called Bio-Physico-Metric Integrated Thermal Care (BPM-ITC), for COPD+MPS. Methods: 10 patients were observed while undergoing 20 sessions of BPM-ITC in 4 weeks. Patients were assessed before and after the protocol using the Medical Research Council (MRC) dyspnea scale, Numeric Pain Rating Scale (NPRS), and the Bio-Postural Questionnaire (BPQ) for bio-physical health status. Treatments included manual therapy of key myofascial trigger points combined with crenotherapy, steam inhalations, mud therapy, vascular path, and water-based motor re-education. Results: At the end of the protocol, clinically relevant improvements were observed in almost all parameters considered in single observed cases; overall statistical analysis of the data highlighted significant positive effects in concomitance with the BPM-ITC protocol. Conclusions: The BPM-ITC protocol was followed by significant clinical improvements in the observed cases, suggesting its potential as a complementary approach for COPD+MPS. Further studies on this topic are recommended. Full article

Background: Dental anxiety is common in pediatric dentistry and may hinder care, particularly in behaviorally challenging children. Most anxiety measures rely on verbal report, which can be unreliable in young patients. This study explored whether the Lüscher Color Test, a non-verbal psychological instrument, shows associations with established anxiety proxies in a pediatric dental sedation setting. Methods: In this single-center prospective observational study, 100 children aged 4–12 years referred for dental treatment in a conscious sedation unit were recruited; 80 completed the protocol (exclusion rate 20%). N₂O/O₂ inhalation sedation was not randomized and was selected by the clinician based on clinical judgement. Anxiety was assessed pre- and post-operative using the Lüscher Color Test, heart rate (HR) monitoring, and the Visual Facial Anxiety Scale (VFAS). The primary outcome was the pre–post change in the Lüscher anxiety index calculated as the pre-operative score minus the post-operative score (Δ = pre − post). Associations between changes in anxiety measures and demographic/clinical variables were examined. Results: Anxiety scores decreased after treatment for both the Lüscher Color Test and VFAS (both p < 0.001). Change in Lüscher scores was positively associated with HR reduction (Spearman r = 0.68; p < 0.01), whereas VFAS change showed a weaker association (r = 0.28; p < 0.05). In regression analyses, treatment-related variables were explored; however, given the observational design and subgroup imbalance, these findings should be interpreted cautiously. Conclusions: Although pre–post scores suggested a reduction in anxiety, the Lüscher Color Test should be considered an exploratory, complementary non-verbal measure rather than a validated diagnostic instrument. In the multivariable logistic regression, nitrous oxide sedation showed only a non-significant trend toward greater anxiety reduction (p = 0.07). Further studies with appropriate validation frameworks and stronger designs are needed before clinical implementation can be recommended. Full article

Background: Coronary artery disease (CAD) commonly coexists with chronic obstructive pulmonary disease (COPD), but may be under-recognised, since symptoms such as dyspnoea and chest discomfort are often attributed to lung disease. We hypothesised that coronary artery disease is highly prevalent in patients with COPD, even in the absence of typical angina symptoms. Methods: This study aimed to detect CAD in patients with COPD. We conducted a single-centre observational study, including 76 patients with no known previous cardiovascular events. To detect ischaemic heart disease, three methods were used, according to standard clinical indications: coronary angiography, coronary CT, and calcium score analysis on chest CT. The findings were categorised according to lesion severity and vessel involvement. Results: A substantial proportion of patients with COPD harboured previously undiagnosed atherosclerotic coronary disease (78%). However, most detected disease was non-obstructive atherosclerosis (56%), whereas severe stenosis was present in approximately one-third of patients (32%). Single-vessel disease accounted for 37% of cases, while the remaining patients exhibited multi-vessel involvement. Nevertheless, only a small proportion of patients had typical angina symptoms (11.8%), and the most frequent complaint was effort dyspnoea (50%). Patients not receiving inhaled corticosteroid therapy were more likely to have extensive coronary artery disease (χ² (6)= 14.228, p = 0.027). Conclusions: These findings support our hypothesis that atherosclerotic coronary disease is often under-recognised in patients with COPD. ICS-containing therapy appeared to be associated with less extensive coronary artery involvement; however, this observation should be interpreted cautiously. Full article

The majority of approved drug products comprise formulations of either chemically synthesized small molecules or large molecular entities derived from living cells, commonly referred to as biologics. Over the past two decades, there has been remarkable growth in the approval of biologics for a variety of disorders, including respiratory diseases. The preference for biologics stems from their high target specificity, strong binding affinity, and favorable safety profiles. Most approved biologics are peptides or proteins, which are unsuitable for oral administration due to negligible bioavailability, resulting from their large molecular size, polarity, and susceptibility to enzymatic degradation in the gastrointestinal tract. Consequently, the majority of biologics are administered parenterally, delivering the drug systemically to reach target sites. However, achieving therapeutic concentrations of locally acting respiratory drugs in the lungs via systemic delivery often requires high doses, which increases the risk of adverse effects. For respiratory disorders, nasal and pulmonary drug deliveries are the preferred noninvasive routes. These routes bypass gastrointestinal and first-pass metabolism and deliver therapeutic agents directly to their local site of action. This approach enables a faster onset of action, reduces the required dose by orders of magnitude, and significantly lowers the risk of systemic adverse effects. These advantages have driven the successful development of inhaled formulations for certain rescue and maintenance medications that were originally administered orally or parenterally. Despite this, treatment options for respiratory diseases remain largely limited to small molecules, with only a single inhaled biologic approved in 1993, even though several parenterally administered biologics have since been approved for pulmonary disorders. The scarcity of inhaled biologics is primarily due to the inherent complexity of these drug substances, which impacts all stages of product development, including manufacturing, characterization, purification, stability, formulation design, delivery, and preclinical and clinical evaluations of safety and efficacy. Additionally, sponsors’ interest in developing inhaled biologics may be tempered by the lack of regulatory guidance addressing the multidisciplinary and intricate nature of their development. This article, together with the accompanying review, addresses both regulatory considerations and scientific challenges in the development of inhaled biologics. To the authors’ knowledge, these works represent seminal efforts to examine available regulatory guidance and the applicable literature across various phases of product development beyond safety and efficacy evaluations. We examined the formal regulatory expectations and summarized the requirements as they apply to inhaled products and inhaled biologic protein therapeutics. In parallel, we explored scientifically relevant considerations in the development of inhalation-specific protein therapeutics for which regulatory guidance remains limited, evolving, or absent. While they should not be considered definitive, it is hoped that these contributions will stimulate scientific and regulatory interest, ultimately promoting the identification and resolution of gaps to advance the development of locally acting biologics and address unmet patient needs. Full article

Inhalation of foreign material is an uncommon condition that occurs more often in dogs than cats. The main aim of this study was to describe signalment, diagnostic investigation, management and outcomes of dogs and cats with tracheobronchial foreign bodies (TBFBs) in four UK referral centres. Ninety-two dogs and 14 cats with a diagnosis of intraluminal TBFBs between January 2012 and July 2019 were included. Labrador retriever was the most commonly represented canine breed (22/92). Cough was the most common presenting complaint, occurring in 89/92 dogs and 9/14 cats. Summer seasonality was recorded in 74/88 dogs, but no feline seasonality was observed. Radiographic suspected TBFB location agreed with definitive location in 15/22 dogs and 2/2 cats. CT-suspected TBFB location and definitive location agreed in 45/46 dogs and 4/5 cats. Most common TBFB location was right caudal lobe bronchus in dogs (35/97) and trachea in cats (6/14). One of 100 canine TBFBs and nine of 14 feline TBFBs were non-vegetal. Single-attempt bronchoscopic retrieval was successful in 88/92 dogs and 13/14 cats. Surgical retrieval was performed in 4/92 dogs. All patients survived to discharge. This study suggests a pattern of canine TBFB seasonality in the UK. Imaging was useful to guide localisation, and CT appeared more accurate at predicting TBFB location than radiography in dogs. Bronchoscopic TBFB removal was commonly successful, with excellent survival rates. Presenting signs, patterns of seasonality, imaging findings, and management outcomes are useful to help clinical reasoning and decision management in the practical setting. Full article

Legionella species are ubiquitous bacteria found worldwide in water, moist environments, soils, and compost. Infection occurs through the inhalation of aerosols, leading to either Pontiac fever or Legionnaires’ disease (LD). Current routine diagnostics typically combine culture-based isolation with Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for species identification and the Latex Agglutination Test (LAT) for serotyping. However, this workflow is fragmented: MALDI-TOF MS lacks serogroup-specific resolution, while LAT relies on subjective visual interpretation. Therefore, this study evaluated Fourier-transform infrared spectroscopy (FT-IR) as a rapid, high-resolution typing method for Legionella isolates to assess its potential as a single-step diagnostic tool. A total of 200 clinical and environmental Legionella isolates were analyzed using FT-IR, including L. pneumophila serogroups (SG) 1–15 and various non-pneumophila species. Spectral data were analyzed using Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA). While MALDI-TOF MS provided accurate species identification, FT-IR spectroscopy demonstrated superior typing capabilities by successfully distinguishing L. pneumophila SG 1 distinct from the SG 2–15 complex and allowing for clear discrimination of most non-pneumophila species. Additionally, FT-IR resolved isolates that showed ambiguous or non-reactive results in LAT. These findings demonstrate that FT-IR overcomes the serotyping limitations of MALDI-TOF MS and offers a more objective, cost-efficient extension to the current multi-step routine, potentially closing the diagnostic gap between simple species identification and deep strain characterization. Full article

Eosinophilic esophagitis (EoE) is a chronic, food-driven inflammatory disorder of the esophagus in which repeated exposure to dietary antigens plays a central role, yet identification of clinically relevant food triggers remains largely empirical. In this retrospective, single-center study, molecular IgE sensitization profiles were descriptively characterized in adult patients with EoE (n = 22) and compared with an allergic control group with chronic urticaria (CU; n = 29) using component-resolved diagnostics. IgE sensitization was common in both cohorts and predominantly reflected inhalant-related, cross-reactive components, particularly PR-10 proteins (63.6% in EoE vs. 37.9% in CU). In contrast, sensitization to structurally stable food allergen components, including lipid transfer proteins and plant storage proteins, was observed in a subset of patients with EoE (31.8%) and was not detected in the control group (0%; p = 0.0015). These food-derived components are characterized by resistance to thermal processing and gastrointestinal digestion and may reflect patterns of sustained dietary exposure rather than acute IgE-mediated reactions. Consistent with previous observations, component-resolved diagnostics showed limited utility for the direct identification of trigger foods in eosinophilic esophagitis. Accordingly, the observed molecular sensitization patterns should be interpreted as descriptive and hypothesis-generating signals rather than as indicators of pathogenic mechanisms or clinical decision-making tools. The findings highlight the importance of considering molecular properties of food allergen components when interpreting sensitization profiles in chronic, non-IgE-mediated inflammatory diseases and underscore the need for prospective studies integrating standardized clinical and dietary outcomes. Full article

Background/Objectives: Clinical remission (CR) is an ambitious and attainable treatment goal for asthma; however, CR definitions vary. Evidence of CR in Japanese patients with moderate-to-severe asthma on inhaled therapies is lacking and was evaluated based on three guideline definitions: the United States Workgroup consensus statement, Japanese Guidelines for adult asthma (JGL), and Practical Guidelines for Asthma Management (PGAM). Methods: Post hoc analysis of Phase III studies including Japanese participants: Japanese subpopulation of CAPTAIN (NCT02924688) and a 52-week Japanese long-term safety study (NCT03184987). CAPTAIN randomized participants to once-daily fluticasone furoate/vilanterol (FF/VI) regimens ± umeclidinium (UMEC). The long-term safety study allocated participants to once-daily FF/UMEC/VI based on asthma control status. All three CR definitions assessed systemic corticosteroid use, severe exacerbations, and asthma control (Asthma Control Questionnaire-5 <1.5 [Workgroup] or ≤0.75 [JGL/PGAM]); Workgroup and JGL also assessed lung function (change from baseline in trough forced expiratory volume in 1 s of ≥0 [stabilized] or ≥100 mL [optimized]). Results: CR attainability varied on definition and thresholds used. At Week 24 in the CAPTAIN Japanese subpopulation, 34–59% and 18–45% of participants (Workgroup; stabilized and optimized), and 21–34% and 8–24% (JGL; stabilized and optimized) met CR criteria across treatment arms. At Week 52 in the long-term safety study, equivalent figures for CR achievement were 33–60%, 22–45%, 11–28%, and 11–23%. Conclusions: This analysis demonstrates that CR, using different definitions and criteria, is an attainable treatment goal with inhaled therapy in Japanese patients with moderate-to-severe asthma not yet eligible for biologics. Full article

Airborne organic dust has rarely been subject to immunotoxicological analysis. A pilot study was undertaken to link exposure metrics (respirable crystalline silica (RCS), bacteria, fungi, endotoxins (END), peptidoglycans (PGN), (1 → 3)-β-D-glucans (GLU)) with in vitro cytotoxicity and cytokine responses based on analysis of airborne organic dust samples collected during a single work shift at six different facilities. The A549 and BEAS-2B cell lines were used to assess cytotoxicity and proinflammatory cytokine release. The general linear model (GLM) and taxonomic linear ordering were used to identify key determinants and rank facilities by the hazard level they pose. The highest cytotoxicity of organic dust was observed at the sewage treatment plant, while the lowest was at the poultry farm. The most hazardous agents present in organic dust included RCS, aerobic bacteria, fungi, PGN, and GLU. They significantly affected cytokine release, particularly of IL-6 and IL-8. The use of a synthetic measure showed that inhalable organic dust from the composting plant presented the highest potential to induce adverse effects on human health, while the lowest one was characterized by the biomass-fired power plant samples. The open-ended statistical method can significantly increase awareness of occupational hazards and promote more responsible protection for exposed workers. Full article

Following the discovery of therapeutic molecules and the identification of specific biological targets, preparation of regulatory dossiers entails extensive product development and characterization to support their safety, efficacy, and stability. We have examined the drug development and relevant regulatory considerations related to inhaled biological proteins in the accompanying article. This review focuses on the characterization of locally acting inhaled biological proteins. Drug product characterization is a regulatory requirement, and it ensures drug product safety, efficacy, stability, and usability by the target populations. Together, these two articles provide a comprehensive discussion based on our review and analysis of the available open literature. We have attempted to fill gaps and simulate discussion of challenges following sound scientific pathways. This approach has the prospect of addressing regulatory expectations leading to rapid solutions to unmet medical needs. The robustness of characterization strategies and the development of analytical methods used in the in vitro testing for the evaluation of drug product attributes is assured through application of the Design-of-Experiment (DOE) and Quality-by-Design (QBD) approaches. Drug product characterization entails a variety of in vitro studies evaluating drug products for purity and contamination, and determination of drug delivery by the intended route of administration. Measurement of the proportion of the labeled amount per dose and the form suitable for delivery to the intended target sites is central to this assessment. For respiratory Drug–Device combination products, the testing may vary with the product designs. However, determination of the single-dose content, delivered-dose uniformity, aerodynamic particle size distribution, and device robustness when used by the target populations is common to all combination products. Characterization of aerosol plumes is limited to inhalation aerosols that produce specific aerosol clouds upon actuation. The flow rate dependency of devices is also examined. Product characterization also includes safety-related product attributes such as degradation products and leachables. For inhaled biological proteins, safety-related in vitro testing includes additional testing to assure maintenance of the three-dimensional structural integrity and the sustained biological activity of the drug substance in the formulation, during aerosolization and upon deposition. This article discusses various tests employed for regulatory-compliant product characterization. In addition, the stability testing and handling of possible changes during product development and post-approval are discussed. Full article

The systems to manipulate a single particle in a microfluidic channel can be adopted to pharmacological and cytological experiments of single-cell observation. The common cell position systems use syringe pumps driven by piezoelectric devices, and these have a flow quantity limit. To achieve single-cell manipulation using actuators without limiting the flow quantity and with a low risk of contamination, we propose a particle control system that uses a sidewall-driven peristaltic micropump driven by pneumatic pressure. The adopted pump was integrated into a single-layer mold with a flow path and was simple to fabricate. Unlike syringe pumps, it not only pumps water forward, but also inhales from the back simultaneously, and can pump indefinitely. We developed a responsive and precise particle position control system using this pump in combination with a high-speed camera. In this system, the pumping pressure is operated by real-time adjustment of a pneumatic pressure supply to realize PID control. This approach moves the particle rapidly when it is far from a designated target position for a quick approach and slowly near the target position to position precisely. Full article

Background/Objective: Osimertinib (OSI) is a third-generation tyrosine kinase inhibitor approved for non-small cell lung cancer (NSCLC) therapy. OSI is administered orally; this route limits the amount of OSI reaching the tumor in the lungs and is associated with serious systemic toxicity. This study aimed to develop a dry powder inhalable formulation to provide tumor-targeted delivery and minimize systemic toxicity. To the best of our knowledge, this is the first study to prepare and evaluate a dry powder inhalation formulation of OSI. Methods: Chitosan-coated PLGA nanoparticles (PLGA-C NPs) encapsulating OSI were prepared using a single emulsion-solvent evaporation technique. PLGA-C NPs were assembled into respirable nanocomposite microparticles (NCMPs) via spray drying with L-leucine as a carrier. PLGA-C NPs were characterized for particle size, zeta-potential, encapsulation efficiency, and in vitro efficacy in A-549 cell line. NCMPs were evaluated for solid-state properties, aerosolization performance, stability and in vitro release. Results: PLGA-C NPs exhibited a particle size of 145.18 ± 3.0 nm, high encapsulation efficiency and a positive zeta potential. In vitro studies demonstrated a 3.6-fold reduction in IC50 compared to free OSI, superior antimigratory effects and enhanced cell cycle arrest. Solid-state characterization of NCMPs demonstrated drug encapsulation in the polymer without chemical interaction. NCMPs exhibited excellent aerosolization (mass median aerodynamic diameter of 1.09 ± 0.23 μm, fine particle fraction of 73.48 ± 8.6%) and sustained drug release (61.76 ± 3.9% at 24 h). Stability studies confirmed the physicochemical stability integrity. Conclusions: These findings suggest that this novel dry powder inhalable OSI formulation may improve therapeutic outcomes while reducing systemic toxicity. Full article

Titanium dioxide (TiO₂) nano- and submicrometric particles’ widespread use in different sectors raised concerns about human and environmental exposure. The validation of analytical methods is essential to ensure reliability in risk assessment studies. In this study, a single-particle inductively coupled plasma mass spectrometry (spICP-MS) method was validated for the detection, quantification, and dimensional characterization of TiO₂ particles in biological tissues. Tissue samples collected after exposure to TiO₂ particles underwent mild acidic digestion using a HNO₃/H₂O₂ mixture to achieve complete matrix decomposition while preserving particle integrity. The resulting digests were analyzed by ICP-MS operated in single-particle mode to quantify and size TiO₂ particles. Method validation was conducted according to ISO/IEC 17025:2017 and included linearity, repeatability, recovery, and detection limit assessments. The limit of detection for TiO₂ particles was 0.04 µg/g, and 55.7 nm was the size the detection limit. Repeatability was within 0.5–11.5% for both TiO₂ mass concentrations and particle size determination. The validated method was applied to tissues from inhalation-exposed subjects, showing TiO₂ levels of 80 ± 20 µg TiO₂/g and particle number concentrations of 5.0 × 10⁵ ± 1.2 × 10⁵ part. TiO₂/mg. Detected TiO₂ particles’ mean diameter ranged from 230 to 330 nm. The developed and validated spICP-MS method provides robust and sensitive quantification of TiO₂ particles in biological matrices, supporting its use in human biomonitoring and exposure assessment studies. Full article