Administration of Bacteriophages via Nebulization during Mechanical Ventilation: In Vitro Study and Lung Deposition in Macaques.

Bacteriophages have been identified as a potential treatment option to treat lung infection in the context of antibiotic resistance. We performed a preclinical study to predict the efficacy of delivery of bacteriophages against Pseudomonas aeruginosa (PA) when administered via nebulization during mechanical ventilation (MV). We selected a mix of four anti-PA phages containing two Podoviridae and two Myoviridae, with a coverage of 87.8% (36/41) on an international PA reference panel. When administered via nebulization, a loss of 0.30-0.65 log of infective phage titers was measured. No difference between jet, ultrasonic and mesh nebulizers was observed in terms of loss of phage viability, but a higher output was measured with the mesh nebulizer. Interestingly, Myoviridae are significantly more sensitive to nebulization than Podoviridae since their long tail is much more prone to damage. Phage nebulization has been measured as compatible with humidified ventilation. Based on in vitro measurement, the lung deposition prediction of viable phage particles ranges from 6% to 26% of the phages loaded in the nebulizer. Further, 8% to 15% of lung deposition was measured by scintigraphy in three macaques. A phage dose of 1 × 109 PFU/mL nebulized by the mesh nebulizer during MV predicts an efficient dose in the lung against PA, comparable with the dose chosen to define the susceptibility of the strain.

Aggregates Associated with Instability of Antibodies during Aerosolization Induce Adverse Immunological Effects.

BACKGROUND: Immunogenicity refers to the inherent ability of a molecule to stimulate an immune response. Aggregates are one of the major risk factors for the undesired immunogenicity of therapeutic antibodies (Ab) and may ultimately result in immune-mediated adverse effects. For Ab delivered by inhalation, it is necessary to consider the interaction between aggregates resulting from the instability of the Ab during aerosolization and the lung mucosa. The aim of this study was to determine the impact of aggregates produced during aerosolization of therapeutic Ab on the immune system. METHODS: Human and murine immunoglobulin G (IgG) were aerosolized using a clinically-relevant nebulizer and their immunogenic potency was assessed, both in vitro using a standard human monocyte-derived dendritic cell (MoDC) reporter assay and in vivo in immune cells in the airway compartment, lung parenchyma and spleen of healthy C57BL/6 mice after pulmonary administration. RESULTS: IgG aggregates, produced during nebulization, induced a dose-dependent activation of MoDC characterized by the enhanced production of cytokines and expression of co-stimulatory markers. Interestingly, in vivo administration of high amounts of nebulization-mediated IgG aggregates resulted in a profound and sustained local and systemic depletion of immune cells, which was attributable to cell death. This cytotoxic effect was observed when nebulized IgG was administered locally in the airways as compared to a systemic administration but was mitigated by improving IgG stability during nebulization, through the addition of polysorbates to the formulation. CONCLUSION: Although inhalation delivery represents an attractive alternative route for delivering Ab to treat respiratory infections, our findings indicate that it is critical to prevent IgG aggregation during the nebulization process to avoid pro-inflammatory and cytotoxic effects. The optimization of Ab formulation can mitigate adverse effects induced by nebulization.

Inhaled bacteriophage therapy in a porcine model of pneumonia caused by Pseudomonas aeruginosa during mechanical ventilation.

BACKGROUND AND PURPOSE 255: Pseudomonas aeruginosa is a main cause of ventilator-associated pneumonia (VAP) with drug-resistant bacteria. Bacteriophage therapy has experienced resurgence to compensate for the limited development of novel antibiotics. However, phage therapy is limited to a compassionate use so far, resulting from lack of adequate studies in relevant pharmacological models. We used a pig model of pneumonia caused by P. aeruginosa that recapitulates essential features of human disease to study the antimicrobial efficacy of nebulized-phage therapy. EXPERIMENTAL APPROACH: (i) Lysis kinetic assays were performed to evaluate in vitro phage antibacterial efficacy against P. aeruginosa and select relevant combinations of lytic phages. (ii) The efficacy of the phage combinations was investigated in vivo (murine model of P. aeruginosa lung infection). (iii) We determined the optimal conditions to ensure efficient phage delivery by aerosol during mechanical ventilation. (iv) Lung antimicrobial efficacy of inhaled-phage therapy was evaluated in pigs, which were anaesthetized, mechanically ventilated and infected with P. aeruginosa. KEY RESULTS: By selecting an active phage cocktail and optimizing aerosol delivery conditions, we were able to deliver high phage concentrations in the lungs, which resulted in a rapid and marked reduction in P. aeruginosa density (1.5-log reduction, p < .001). No infective phage was detected in the sera and urines throughout the experiment. CONCLUSION AND IMPLICATIONS: Our findings demonstrated (i) the feasibility of delivering large amounts of active phages by nebulization during mechanical ventilation and (ii) rapid control of in situ infection by inhaled bacteriophage in an experimental model of P. aeruginosa pneumonia with high translational value.

Controlled Heat and Humidity-Based Treatment for the Reuse of Personal Protective Equipment: A Pragmatic Proof-of-Concept to Address the Mass Shortage of Surgical Masks and N95/FFP2 Respirators and to Prevent the SARS-CoV2 Transmission.

Background: The coronavirus infectious disease-2019 (COVID-19) pandemic has led to an unprecedented shortage of healthcare resources, primarily personal protective equipment like surgical masks, and N95/filtering face piece type 2 (FFP2) respirators. Objective: Reuse of surgical masks and N95/FFP2 respirators may circumvent the supply chain constraints and thus overcome mass shortage. Methods, design, setting, and measurement: Herein, we tested the effects of dry- and moist-air controlled heating treatment on structure and chemical integrity, decontamination yield, and filtration performance of surgical masks and FFP2 respirators. Results: We found that treatment in a climate chamber at 70°C during 1 h with 75% humidity rate was adequate for enabling substantial decontamination of both respiratory viruses, oropharyngeal bacteria, and model animal coronaviuses, while maintaining a satisfying filtering capacity. Limitations: Further studies are now required to confirm the feasibility of the whole process during routine practice. Conclusion: Our findings provide compelling evidence for the recycling of pre-used surgical masks and N95/FFP2 respirators in case of imminent mass shortfall.

Protein stability during nebulization: Mind the collection step!

Inhaled protein therapeutics meet a growing interest for the treatment of respiratory diseases. In liquid aerosols, proteins face stresses that may generate instabilities, such as physicochemical denaturations, aggregation and loss of activity. Monitoring protein stability is thus crucial but implies collection of aerosol droplets before analysis. Many aerosol collection methods may be used, still their interference on protein stability is unknown. In this study, we compared the impact of six aerosol samplers on the stability of a model monoclonal antibody (Ig1), aerosolized with a mesh nebulizer. Ig1 stability was assessed for aggregation and biological activity. The six aerosol samplers generated distinct aggregation profiles for Ig1 at all size scales; counts of micron-sized particles varied by a factor of 100. The heterogeneity did not impact Ig1 activity, which was not significantly changed after nebulization. To extrapolate these results, we evaluated the impact of two samplers on three other proteins. Depending on the protein, samplers gave discordant aggregation and/or activity profiles, sometimes in the reverse trend as compared to Ig1. In conclusion, aerosol samplers interfere with protein stability; this impact depends both on the samplers and the protein, highlighting the importance of using the same collection device throughout the aerosol development process.

[Biosimilar monoclonal antibodies: comparative study of analytical and functional quality]. / Anticorps monoclonaux biosimilaires - Étude comparative des qualités analytique et fonctionnelle.

Biosimilars marketing authorization requires a strict demonstration of similarity with the reference antibody, through preclinical and clinical studies. This article reviews the panel of in vitro physicochemical and functional analyses, which are performed prior to clinical studies. For each critical attribute of the antibody, we detail the commonly used analytical techniques, their working principle and the type of information they may give.

TITLE: Anticorps monoclonaux biosimilaires - Étude comparative des qualités analytique et fonctionnelle. ABSTRACT: La mise sur le marché de biosimilaires requiert une démonstration stricte de la similarité avec l'anticorps de référence, au travers d'études précliniques et cliniques. Cet article synthétise l'ensemble des analyses physicochimiques et fonctionnelles mises en œuvre in vitro, préalables à la réalisation d'études cliniques. Pour chaque caractéristique critique de l'anticorps, nous avons détaillé les techniques analytiques communément employées, leur principe de fonctionnement, ainsi que le type d'informations que ces techniques permettent d'obtenir.

ERS International Congress 2018: highlights from best-abstract awardees.

A summary of the ERS International Congress 2018 from the best-abstract awardees for each ERS Assembly and their views on the evolving field of research of their respective Assemblies http://ow.ly/c0eq30ntKuw.

MAbDelivery: Administration routes for antibody therapy Third LabEx MAbImprove industrial workshop, July 2, 2015 Tours, France.

The annual "LabEx MAbImprove Industrial Workshops" are primarily intended to provide a comprehensive view about topics of interest for the pharmaceutical industry to scientists involved in research on therapeutic antibodies. The third workshop in this series, held July 2, 2015 in Tours, was dedicated to the optimization of delivery, namely all processes leading monoclonal antibodies to reach their target site. The commonly used intravenous (IV) route, although advantageous in terms of pharmacokinetics and pharmacodynamics, presents some disadvantages in terms of patients' convenience, therapeutic target access or treatment cost. Such problems led pharmaceutical companies to consider more straightforward and patient-friendly administration routes, bringing the need for specific formulations adapted to the specific inherent physicochemical challenges. In this context, the workshop provided an overview of these advances and opened discussion on new administration routes and formulation development. In the first session, the opportunities and challenges of 3 main routes of administration (IV, subcutaneous (SC), and pulmonary) were discussed, integrating protein stability issues. The next session was dedicated to medical devices intended for SC and pulmonary administration. The last session focused on specific formulations for monoclonal antibodies, particularly to successfully protect antibodies upon aerosolization, to develop highly concentrated formulations for SC administration, and to use formulation as a mean to overcome the barriers to oral protein delivery. As in the previous editions, this workshop gathered people from the academic and industrial spheres and allowed rich debates and discussions.

Inhaled phage therapy: a promising and challenging approach to treat bacterial respiratory infections.

INTRODUCTION: Bacterial respiratory tract infections (RTIs) are increasingly difficult to treat due to evolving antibiotic resistance. In this context, bacteriophages (or phages) are part of the foreseen alternatives or combination therapies. Delivering phages through the airways seems more relevant to accumulate these natural antibacterial viruses in proximity to their bacterial host, within the infectious site. Areas covered: This review addresses the potential of phage therapy to treat RTIs and discusses preclinical and clinical results of phages administration in this context. Recent phage formulation and aerosolization attempts are also reviewed, raising technical challenges to achieve efficient pulmonary deposition via inhalation. Expert opinion: Overall, the inhalation of phages as antibacterial treatment seems both clinically relevant and technically feasible. Several crucial points still need to be investigated, such as phage product pharmacokinetics and immunogenicity. Furthermore, given phage-specific features, appropriate regulatory and manufacturing guidelines will need to be defined. Finally, randomized controlled clinical trials should be carried out to establish phage therapy's clinical positioning in the antimicrobial arsenal against RTIs.