Journal of Aerosol Medicine and Pulmonary Drug DeliveryAhead of Print AbstractsFree AccessAbstracts from The Aerosol Society Drug Delivery to the Lungs 33Edinburgh International Conference Centre Edinburgh, Scotland, UK December 7–9, 2022Published Online:24 May 2023https://doi.org/10.1089/jamp.2023.ab01.abstractsAboutSectionsPDF/EPUB Permissions & CitationsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail Abstracts: Drug Delivery to the Lungs 3301. DRUG DELIVERY OVER THE LAST 100 YEARS...AND THE FUTUREFederico Lavorini, MD, PhDDepartment of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, Florence, 50134, ItalySummary: Inhalation therapy is one of the oldest approaches to the therapy of diseases of the respiratory tract. It is well recognised today that the most effective and safe means of treating the lungs is to deliver drugs directly to the airways. Surprisingly, the delivery of therapeutic aerosols has a rich history dating back more than 2000 years to ayurvedic medicine in India. In the late 18th and in the 19th century, earthenware inhalers were popular for the inhalation of air drawn through infusions of plants and other ingredients. Atomizers and nebulizers were developed in the mid‐1800s in France and were thought to be an outgrowth of the perfume industry as well as a response to the fashion of inhaling thermal waters. The marketing of the first pressurized metered‐dose inhaler for epinephrine and isoproterenol, by Riker Laboratories in 1956, was a milestone in the development of inhaled drugs. The first dry powder inhaler (DPI) was developed in the mid‐19th century, but DPIs did not gain market prominence until the 1990s. The signing of the Montreal Protocol in 1987 led to a surge in innovation that resulted in the diversification of inhaler technologies with significantly enhanced delivery efficiency, including modern pMDIs, dry powder inhalers, and nebuliser systems. There is also great interest in tailoring particle size and deliver to treat specific areas of the respiratory tract. One challenge that has been present since antiquity still exists, however, and that is ensuring that the patient has access to the medication and understands how to use it effectively. patient compliance will likely lead to market acceptance of smart inhalers. However, the desire for high‐tech inhalers will be countered by the increasing healthcare cost pressures and will likely ensure that MDI and DPI therapies remain important components of therapeutic aerosol delivery.02. CHANGE IS IN THE AIR ‐ THE NEW PRESSURIZED METERED‐DOSE INHALER PROPELLANTSJohn N Pritchard11Inspiring Strategies, Leicester, LE6 0AF, UKSummary: Climate change is increasingly at the forefront of public and political discussions. The fact that the hydrofluorocarbons (HFCs) currently used as propellants in pressurized metered‐dose inhalers (pMDIs) have relatively high global warming potential (GWP) has led to their usage becoming increasingly subject to legislation. Recent acceleration of the overall phase down of HFCs, notably in the European Union and in California, could put the availability of affordable pMDI medication at risk towards the end of this decade. At the same time, it is likely that the cost of bulk HFC‐134a and ‐227 propellants will rise substantially over the next few years as other industrial uses decline, and quota mechanisms further impact on availability. Taken together, this could lead to a shortage of affordable reliever medication, even if new exemptions for medical uses were to be introduced.Three companies have stated publicly that they are actively developing lower‐GWP pMDIs. However, only one is a major supplier of rescue medication, which accounts for more than 60% of all emissions from pMDIs. Whilst targeting first launches in 2025, these timelines are at risk if the health authorities require full clinical development programmes to be completed for a change of the propellant, when there are no other substantial changes in the formulation The pharmaceutical industry needs to respond with lower‐GWP alternatives whilst at the same time, regulators need to work with the industry to expedite the approval of such new products if essential patient medication is not to be put at risk in the Western world.03. IN‐SILICO PREDICTION OF PMDI PERFORMANCE WITH LOW‐GWP PROPELLANTS HFA‐152A AND HFO‐1234ZE(E)Daniel Duke1, Lingzhe Rao1, Nirmal Marasini2, Hui Xin Ong2, David Schmidt3, Benjamin Myatt4, Phil Cocks4 & Paul Young21Laboratory for Turbulence Research in Aerospace & Combustion (LTRAC), Department of Mechanical & Aerospace Engineering, Monash University, Clayton, 3800, Australia2Respiratory Technology, Woolcock Institute of Medical Research, Glebe, Sydney, NSW 2037, Australia3University of Massachusetts‐Amherst, Amherst, MA 01003, United States of America4Kindeva Drug delivery, Charnwood Campus, 10 Bakewell Road, Loughborough, United Kingdom, LE11 5RBSummary: The transition to low greenhouse warming potential propellants for pressurised metered dose inhalers will necessarily require a redesign of the nozzle orifice to compensate for changes in physicochemical properties such as reduced vapour pressure, density, and increased saturation temperature. New propellants have reduced spray momentum, reduced flash‐evaporation, altered spray morphology resulting in larger primary droplet size at the orifice. Investigating these phenomena is challenging due to the large parameter space for orifice and actuator design and multiple propellant candidates that must be searched in order to find an optimal arrangement. A cost‐effective solution to this problem is the use of in silico models which can search the parameter space quickly by running dozens of detailed computational fluid dynamics simulations on hundreds to thousands of processors. We present the first results of a parametric study of the effect of orifice diameter and length for solution formulations with propellants HFA‐134a, HFA‐152 and HFO‐1234ze(E). The simulations are capable of capturing trends in near‐orifice spray structure and accurately predicting droplet size. We show that manipulation of the orifice geometry may be able to compensate for the differences between propellants.04. CARBON FOOTPRINT IMPACT ON INHALERSChrister JansonDepartment of Medical Sciences: Respiratory, Allergy and Sleep Research, Uppsala University, Uppsala, SwedenThat inhalation therapy can harm the environment became apparent in the 1990s when pressurised metered dose inhalers (pMDI)s that used chlorofluorocarbons (CFC) had to be replaced because of the depleting effect of CFCs on atmospheric ozone. CFC‐containing pMDIs were replaced with dry powder inhalers (DPI), soft mist inhalers (SMI) and pMDIs that used HFCs as propellant. There were large differences between countries in how CFC‐ pMDIs were replaced, with DPI becoming the dominating type of device in Sweden while pMDIs dominated in the UK [1].It was recently discovered that HFCs also were problematic from an environmental perspective as the ones used in pMDIs (HFA 134a and HFA 227ea) had a considerable global warming potential of 1300 to 3000 times larger than that of CO2. Consequently, the carbon footprint of treating asthma or COPD with pMDIs is approximately 20 times higher than giving a similar treatment using DPIs [2] or SMIs [3]. A retrospective analysis of a pragmatic trial indicated that it is possible to switch asthmatics from pMDI to DPI and thereby significantly reduce carbon footprints without losing asthma control [4].05. EFFECT OF AIRWAY DISEASE ON DRUG DEPOSITION IN THE LUNGChantal Darquenne11University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093‐0623, USASummary: Drug inhalation is a mainstay in the management of respiratory diseases. Its success not only depends on the pharmacology of the drugs being inhaled but also on the site and extent of deposition in the respiratory tract. Such deposition is tightly related to the physical properties of the inhaled aerosols (shape, size, density, electrostatic charge) and to the characteristics of the subject (lung geometry and size, breathing pattern, disease state). The most relevant deposition mechanisms for pharmaceutical aerosols are inertial impaction, a velocity‐dependent mechanism, and gravitational sedimentation, a time‐dependent mechanism. Increasing airflow rates increase the efficiency of deposition by inertial impaction and decreases that by sedimentation while increasing tidal volumes allow particles to reach more distal regions of the lung, where deposition by sedimentation is likely to occur.06. EVALUATION OF TUMOUR EXPOSURE FOLLOWING THE ADMINISTRATION OF AN INNOVATIVE CISPLATIN DRY POWDER FOR INHALATION AT DIFFERENT DOSE LEVELS AND REGIMENSN. Wauthoz1, S. Chraibi1, T. Davenne1,2, P. Gérard2, R. Rosière1,2, K. Amighi11Unit of Pharmaceutics and Biopharmaceutics, Université libre de Bruxelles (ULB), boulevard du Triomphe, Campus plaine CP207, 1050 Brussels, Belgium – Nathalie.wauthoz@ulb.be2InhaTarget Therapeutics, Rue Antoine de Saint Exupéry 2, 6041 Gosselies, BelgiumSummary:Introduction: A cisplatin‐based dry powder for inhalation (CIS‐DPI‐50) was developed to be administered during the off‐cycles of conventional anticancer therapies to intensify tumour exposition to chemotherapy. The aim was to evaluate the exposure of lung tumour and organs to platinum after CIS‐DPI‐50 administration in lung tumour‐bearing mice.Methods: Pharmacokinetic and biodistribution studies were conducted following different cisplatin dose levels and regimens in the LLC1‐Luc model.Results: After a single administration of CIS‐DPI‐50 at 0.5 mg/kg, platinum concentrations in the lung tumour were immediately high and increased slowly until reaching Cmax 2h later (20 ± 17 ng/mg) before decreasing gradually. This led to an AUC0‐∞ of 10,683 ± 5,837 ng.min.mg‐1 in the lung tumour, which was nearly 10‐fold higher than the AUC0‐∞ in tumour‐free lungs (1,072 ± 825 ng.min.mg‐1). This trend was also observed at different dose levels and regimens within a week with platinum concentration in the lung tumour 2‐fold (with 0.5 mg/kg/day x 3 days), 4‐fold (with 0.5 mg/kg/day x 5 days) and up to 6‐ fold higher (with 1 mg/kg/day x 5 days) than in tumour‐free lungs. Moreover, it seemed that the higher the weekly dose was, the higher the concentration in the lung tumour, which tended to demonstrate a higher penetration within the lung tumour than in tumour‐free lungs due to a diffusion effect based on the gradient of concentration.Conclusion: Single and repeated.07. AEROSOLISED PHOSPHODIESTERASE 3 INHIBITOR ENOXIMONE IN THE TREATMENT OF COVID‐19 PNEUMONIA: IN VITRO EVALUATIONS SUPPORTING CLINICAL EVIDENCEA. M. Piras1, B. Grassiri1, C. Migone1, Y. Zambito1, A. M. Healy2,3, C. Ehrhardt3, P. Roncucci4 and B. Ferro41Department of Pharmacy, University of Pisa, Pisa/56126, Italy2SSPC, The Science Foundation Ireland Research Centre for Pharmaceuticals, Ireland3School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin 2, Ireland4Departments of Anesthesia and Critical Care, Spedali Riuniti Livorno Estav Nordovest, Livorno/57121, ItalySummary: Enoximone (ENOX) is a phosphodiesterase‐3 (PDE‐3) inhibitor, which is clinically applied in congestive heart failure, having vasodilating and positive inotropic activity. It is commercially available as an i.v. aqueous formulation (PERFAN®), containing ethanol and propylene glycerol as co‐solvents. The aim of this work is to support the encouraging clinical preliminary results observed with the off‐label pulmonary administration of PERFAN®, through the inhalation route, in patients affected by COVID‐19‐related acute respiratory distress syndrome (CARDS). PERFAN® aerosolisation was characterised in terms of delivered dose, aerodynamic droplet size distribution and applied to in vitro models dedicated to IVIV correlation. The results demonstrate that ENOX is capable of a local direct effect on human pulmonary epithelial cell line NCI‐H441, increasing intracellular cAMP levels and providing protection from oxidative stress. Furthermore, the delivered drug permeates across the in vitro monolayer model, suggesting good in vivo bioavailability to achieve a vasodilatory effect. It was also noted that the in vivo effect is due to about ∼30% of the delivered PERFAN® dose (50 mg), since ENOX precipitates rapidly in the nebuliser cup during the aerosolisation. However, the droplets produced on nebulisation have a MMAD of 5 μm and GSD of 2, indicating a favourable size and size distribution for deposition in the bronchi‐alveolar region. Beyond the beneficial exploitation of the off‐label PERFAN® administration, this research opens up future development of ENOX inhalable medicines.08. TRANSLATION OF INHALED EXPOSURE THROUGHOUT DRUG DEVELOPMENT: A CASE‐STUDY ON HOW TO DE‐RISK FORMULATION DEVELOPMENT AND SECURE CLINICAL EXPOSURERebecca Fransson1, Carolyn Stevensson2 & Ulrika Tehler11Advanced Drug Delivery, Pharmaceutical Science, R&D, AstraZeneca, 43183 Gothenburg, Sweden2Early Product Development & Manufacturing, Pharmaceutical Science, R&D, AstraZeneca, 43183 Gothenburg, SwedenSummary: Biopharmaceutics is a skill area residing within pharmaceutical sciences and relates the physicochemical properties of a drug in a dosage form to the pharmacology, toxicology, or clinical response observed after its administration. The major responsibility of a biopharmaceutics expert within the industrial setting is to ensure that the drug product reliably delivers the intended exposure in animal and clinical studies. Specialized inhalation biopharmaceutics focuses on drug delivery to, and sometimes, through the lungs. Inhaled drug delivery requires expert knowledge within several scientific disciplines, but the core technical skill areas for an inhaled biopharmaceutics researcher resides within the aerosol testing, dissolution and absorption area. Scientific understanding on how the formulation, the inhalation device and relevant physiology impacts the drug product performance is the mainstay of an inhaled biopharmaceutics representative assignment in the industrial setting.09. DELIVERY DEVICE AND METHOD FOR AEROSOL PATHOGEN EXPOSURE AND INHALED THERAPEUTIC IN A MACAQUE MODELJustina Creppy1,2, Benoit Delache1, Maria Cabrera2, Georges Roseau3, Cécile Herate1, Thibaut Naninck1, Asma Berriche1, Quentin Sconosciuti1, Eléana Navarre1, Frederic Ducancel1 & Laurent Vecellio2,31CEA/IDMIT, Fontenay aux Roses, France2CEPR, INSERM U1100, University of Tours, Tours, France3PST‐A, University of Tours, Tours, FranceSummary: The main objective of this study was to develop an inhalation delivery device for macaque allowing either pathogen and drug administration. Using an inhalation device close to human device, it will allow rapid transfer to clinical trial and will give a high level of confidence if human study is not possible. Aerosol deposition measurement in 3 macaques have been performed by gamma camera using five different nebulizers with a face mask: one standard jet nebulizer with a 0.4μm MMAD, one standard jet nebulizer with a 3.2μm MMAD, one standard jet nebulizer with a 13.9μm MMAD, one prototype of jet nebulizer with 3.9μm MMAD and a second prototype using mesh nebulizer with a 3.9μm MMAD. Results show a decrease of aerosol deposition variability when using prototypes in comparison with standard jet nebulizer (34% and 30% respectively for prototype 1 and 2 vs 54%, 61%, 75% for standard nebulizers). Mesh nebulizer has the higher efficiency in terms of total airways deposition (37% vs 2.5% in terms of nebulizer charge) and lung targeting. PET‐Scan measurement using prototype number 2 confirms its ability to target the whole macaque.10. CONSTRUCTION OF A FULL AIRWAY VOLUME “TOTAL INHALABLE DEPOSITION IN AN ACTUATED LUNG” (TIDAL) MODEL FOR APPROXIMATING SPATIAL DEPOSITION UNDER BREATHING PROFILESIan R Woodward1 & Catherine A Fromen11University of Delaware, Department of Chemical and Biomolecular Engineering, 150 Academy St. Newark, DE 19808, USASummary: New preclinical experimental approaches are needed to measure the spatial deposition of inhaled aerosols and improve evaluation of orally inhaled and nasal drug products, leading to the development of new vaccines and therapeutics, as well as bioequivalent assessments of generic options. To address this, our lab has created a multiscale dynamic preclinical tool to spatial measure deposition as a function of patient‐specific breathing, anatomy, and disease state. Coined the “total inhalable deposition in an actuated lung” (TIDAL) model, this platform leverages advances in additive manufacturing to recreate spatial aerosol collection efficiencies across the five lung lobes. TIDAL represents an innovative life‐ size physical model built of moving, modular, plug‐and‐play components that faithfully recreates the essential physical phenomena occurring in both inhaled formulation and the lung. A full TIDAL model representing an adult male has been fabricated and used to assess spatial deposition under physiological breathing conditions. Five sealed elastic lobe units filled with latticed parts actuated to create independent airflow by expansion and contraction under cycles of compression and release within the sealed compartment. We have successfully achieved breathing profiles with asymmetric lobe involvement, tunable flow rates and volume exchange, and breath holds. Aerosols are introduced at the mouth inlet and following designated breathing cycles, deposition is quantified on the latticed parts following a wash. Differential lattice structures provide spatial collection, where finer lattices increase the local deposition to benchmark to clinical observations. Overall, this work demonstrates important proof‐of‐concept towards developing the preclinical TIDAL model.11. CAN WE MAKE BETTER USE OF ROUTINE PHYSIOLOGICAL SIGNALS? USING MATHS TO IMPROVE THE SENSITIVITY OF DETECTING DRUG OR DISEASE‐INDUCED CHANGESManasi Nandi1, Miquel Serna Pascual1, Maria Volovaya1, Yujia Wu1, Rebecca D'Cruz2, Philip Aston3, Carolyn Lam1,4, Aileen Milne4, Mary McElroy41School and Cancer and Pharmaceutical Sciences, King's College London, Franklin Wilkins Building, 150 Stamford Street, London, U.K2Department of Mathematics, Centre for Mathematical and Computational Biology, University of Surrey, Guildford Surrey U.K3Lane Fox Respiratory Unit, Guys and St Thomas’ NHS Foundation Trust, London, U.K4Discovery Pharmacology and Toxicology, Charles River, Edinburgh, U.KSummary: Symmetric Projection Attractor Reconstruction (SPAR) is a newly developed mathematical technique. It quantifies the shape and variability changes of cyclic waveforms by using all the available digital data, most of which is typically discarded during conventional analysis. We demonstrate the additive value of this technique in more sensitively quantifying lung function changes in a preclinical lung fibrosis model and in patients with COPD.12. A TEST OF THE SAME DOSE OF A FINE AND A COARSE AEROSOL IN DOG SURPRISINGLY INDICATED NEGLIGIBLE INTRANASAL FILTRATIONMikael Brülls1, Steven Oag1 & Eva Lamm Bergström11AstraZeneca BioPharmaceuticals R&D, AstraZeneca R&D Gothenburg, Mölndal, SE‐431 83, SwedenSummary: A novel inhalation exposure system was developed to increase the efficiency of pharmacokinetic (PK) evaluations of inhaled drugs in a large species such as the dog by enabling simultaneous administration of multiple drugs to the same animal in a single experiment, facilitating a direct comparison of the same lung dose of different drugs using the same blood samples, which can be considered to be a refinement measure from an animal research perspective.When validating the system in vivo, which included a comparison of the same nebulized dose of a fine and coarse aerosol, no detectable difference in lung deposited dose was observed. We expected the aerosol droplet size to have an impact and were surprised by the results, which indicated negligible intranasal filtration.The intentionally extremely poorly soluble drugs selected for this study were developed for local treatment of the lung via inhalation. The three drugs were known to have low oral bioavailability and expected to also have low nasal bioavailability, because it has been shown [1‐3] that drugs such as mometasone furoate, fluticasone propionate and fluticasone furoate have low nasal bioavailability (<1%) due to poor solubility. The solubilities of the selected drugs are as low or even lower than the mentioned drugs. It was thus expected that the systemic exposure would be derived primarily from pulmonary absorption. This facilitated the determination of the lung deposited dose by a PK assessment.This finding disproves the assumption that a mouth tube is required in dog studies to eliminate the high filtration that is believed to occur during nasal inhalation. The option of using nasal breathing instead of a mouth tube in dog studies is less invasive and considered a refinement measure from an animal research perspective.13. DEVELOPMENT OF AN IMMUNOGENIC SPRAY‐FREEZE‐DRIED POWDER VACCINE AGAINST SARS‐COV‐2Harry W. Pan1, Jian‐Piao Cai2, Kwok‐Yung Yuen2, Jenny K.W. Lam1,31Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong2Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong3Department of Pharmaceutics, UCL School of Pharmacy, University College LondonSummary: After more than two years of experience with SARS‐CoV‐2, a suite of vaccines has become available as part of the global efforts to contain the rapid spread and devastating impact of the pandemic. Like many other liquid vaccines, currently approved COVID‐19 vaccines are intramuscular injections. While this invasive route of administration has acquired strong evidence of efficacy, other delivery methods may be more advantageous. In the context of COVID‐19, mucosal immunity in the respiratory tract would be highly beneficial, given that is it typically the first point of viral entry. In this study, a dry powder vaccine based on the receptor‐binding domain (RBD) of the SARS‐CoV‐2 spike protein was developed for intranasal inhalation. Spray‐freeze‐drying with an ultrasonic nozzle was applied to produce porous particles adequate for aerosolisation to the nasal airway. The formulation was a mixture of the antigen, aluminium hydroxide gel as adjuvant, and 2‐hydroxypropyl‐beta‐cyclodextrin as cryoprotective and lyoprotective agent. The spray‐freeze‐dried powder was characterised in terms of particle size by laser diffraction and morphology by scanning electron microscopy. The median volume diameter of the spherical particles was approximately 38 μm, which is suitable for nasal deposition in humans. The antigen‐adjuvant binding efficiency measured by polyacrylamide gel electrophoresis was 68%, a reduction from 87% before drying. Preliminary in vivo assessment of the vaccine delivered via intratracheal administration induced remarkable immune responses in mice. Together, the results indicate that this solid‐state vaccine possesses physical characteristics appropriate for intranasal delivery and is a promising alternative to parenteral COVID‐19 vaccines.14. NASAL POWDER DELIVERY – CHARACTERISATION OF THE INFLUENCE OF EXCIPIENTS ON DRUG ABSORPTIONMarie Trenkel & Regina ScherließKiel University, Department of Pharmaceutics and Biopharmaceutics, Grasweg 9a, 24118 Kiel, GermanySummary: The nasal physiology has high potential for systemic drug delivery, while at the same time the natural clearing mechanism poses a specific challenge. The formulation of nasal powders and the use of mucoadhesive excipients are possible strategies to overcome this hurdle. For a targeted selection of excipients, the knowledge of their influence in the process of drug absorption through the nasal mucosa is essential. For that purpose, the effects of two fillers (mannitol, microcrystalline cellulose) and three mucoadhesives (pectin, chitosan glutamate and hydroxypropyl cellulose) as excipients in nasal powder formulations with atenolol as model drug were investigated. We evaluated the ability of the formulations to prolong the nasal residence time of the drug by assessing their influence on the viscoelasticity of simulated nasal fluid. Undissolved drug particles increased the elasticity to an extent that slows down the mucociliary clearance. Characterisation of the dissolution and release of the drug on a wet surface in a Franz cell setup revealed a decrease in dissolution rate for formulations that contained insoluble or gelling excipients. This may be beneficial for drugs that show fast dissolution but low permeability, since undissolved or swollen particles, which slow mucociliary clearance, remain longer in the nasal cavity. In order to assess drug permeability, we used the nasal carcinoma cell line RPMI 2650 in an air‐liquid interface model. The separate evaluation of the dissolution and permeability processes is essential for the understanding of the influence of excipients in the nose and thus will enable an effective selection in product development.15. GENERATION AND CHARACTERISATION OF AN ORGANOTYPIC CELL KNOCKOUT MODEL TO STUDY PULMONARY MRP1Johannes A. Sake1, Lyubomyr Burtnyak2, Mohammed Ali Selo1,3, Severin Mairinger4,5, Henriette E. Dähnhardt1, Camelia Helbet1, Vincent P. Kelly2, Oliver Langer4,5, Carsten Ehrhardt11School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Dublin, Ireland2School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland3Faculty of Pharmacy, University of Kufa, AL‐Najaf, Iraq4Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria5Department of Biomedical Imaging and Image‐guided Therapy, Medical University of Vienna, Vienna, AustriaSummary: We recently reported a contribution of multidrug resistance‐associated protein 1 (MRP1/ABCC1) to pulmonary drug absorption in vivo. To study pulmonary MRP1 function in vitro, an organotypic knockout model based on the human NCI‐H441 distal lung epithelial cell line was generated and characterised.A CRISPR/Cas9 technique using the knock‐in/promoter trap method was employed. Pre‐assembled spCas9 protein/gRNA construct and repair template were delivered to NCI‐H441 cells by electroporation. Repair templates contained puromycin resistance and mCherry fluorescence genes. The successful knock‐in was evaluated by puromycin selection and mCherry detection via flow cytometry. In the thus generated clones ABCC1 gene and MRP1 protein expression were compared to wild‐type (WT) cells by real‐time polymerase chain reaction (qPCR) and immunoblot, respectively. Transporter activity was studied using 6‐bromo‐7‐methylpurine (BMP), a prodrug of the MRP1‐specific substrate S‐(6‐(7‐methylpurinyl))glutathione (MPG).Initially, eight KO clones (M1–M8) were generated, of which only M1 and M2 showed significantly (p ≤ 0.001) reduced ABCC1 mRNA levels, while MRP1 protein was undetectable in all clones. Transport studies in M2 revealed significantly (p ≤ 0.001) reduced release of MPG compared to WT cells. The inhibitory effect was comparable to the MRP1 inhibitor MK‐571.We successfully generated MRP1 KO clones, which can be used to study the potential influence of MRP1 on pulmonary drug disposition and physiology on mechanistic levels in vitro.16. SIMULTANEOUS NASAL AND LUNG DELIVERY OF AN ANTIVIRAL METALLODRUG USING A DUAL TARGETING POWDER FORMULATIONHan Cong Seow1, Suyu Wang2, Hongzhe Sun2 & Jenny K.W. Lam1,31Department of Pharmacology and Pharmacy, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR2Department of Chemistry, State Key Laboratory of Synthetic Chemistry, CAS‐HKU Joint Laboratory of Metallomics on Health and Environment, The University of Hong Kong, Pokfulam, Hong Kong SAR3Department of Pharmaceutics, UCL School of Pharmacy, University College London, UKSummary: In the fight against respiratory viral infections, new aerosol drug delivery strategies are developed to target the entire respiratory tract. As highly contagious and deadly viruses infect both the upper and lower respiratory tract, an antiviral therapy that can deliver to the target sites would be most effective. This study aimed to reformulate ranitidine bismuth citrate (RBC), an anti‐ulcer drug with broad‐spectrum coronavirus activity, as a dual particle size powder formulation that targets both the nasal cavity and deep lung by a single route of intranasal administration. Spray freeze drying (SFD) using appropriate atomising nozzles produces distinctly large (>10 μm) and small (<5 μm) particles for nasal and lung deposition, respectively. When dispersed from a nasal device, the aerosol performance of the powder was evaluated using the Next Generation Impactor (NGI) coupled with a glass expansion chamber. By blending two formulations with different particle sizes, a single powder formulation with bimodal size distribution and dual aerosol deposition characteristics was produced. The aerosol deposition profile can potentially be manipulated by varying the powder mixing ratio. Compared to orally administered unformulated RBC, intratracheal administration of a lower dose of SFD powder to mice resulted in significantly higher drug concentration in the lungs. Overall, a dual targeting powder formulation of RBC with customisable nasal and lung deposition profile was developed. This innovative formulation strategy may potentially be applied to deliver therapeutic agents to the human airways for respiratory diseases.17. DEVELOPMENT OF INHALED PLATELET‐BASED THERAPY TO REPAIR DAMAGED LUNGSZiru Xu, Ben Forbes, Simon Pitchford & Magda SwedrowskaKing's College London, Institute of Pharmaceutical Science, London SE1 9NH, UKSummary: As the firs