ABSTRACT
INTRODUCTION: TOBI® Podhaler™ is a capsule-based drug-device combination (tobramycin inhalation powder [TIP] 28 mg capsules via unit-dose dry powder T-326 Inhaler [Podhaler™]) developed for treatment of Pseudomonas aeruginosa infection in cystic fibrosis (CF). We explored how inspiratory flow profiles and mouth-throat geometries affect drug delivery with the T-326 Inhaler. METHODS: Inspiratory flow profiles were recorded from 38 subjects aged 6-71 who had CF and varying degrees of lung function impairment. Ten of the inspiratory flow profiles were simulated in the laboratory using a custom breath simulator to determine delivered dose (DD) from the T-326 Inhaler. In vitro total lung dose (TLDin vitro ) was measured using four anatomical throat models, ranging from a child to a large adult. RESULTS: Aerosol performance was assessed across a range of inspiratory flow profiles. Mean DD ranged from 88.8% to 97.0% of declared capsule content. TLDin vitro ranged from 54.8% to 72.4% of capsule content between the flow profile/throat options tested, and the mean TLDin vitro across the range of flow profiles and anatomical throats tested was 63 ± 5%. CONCLUSIONS: Our findings indicate that the T-326 Inhaler provides reliable drug delivery at flow rates likely to be achieved by a broad spectrum of patients with CF. Importantly, forceful inhalation was not required to achieve a robust TLDin vitro . Pediatr Pulmonol. 2016;51:1159-1167. © 2016 Wiley Periodicals, Inc.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Cystic Fibrosis/microbiology , Lung/microbiology , Models, Biological , Pharynx , Pseudomonas Infections/drug therapy , Tobramycin/therapeutic use , Administration, Inhalation , Adult , Anti-Bacterial Agents/administration & dosage , Child , Cystic Fibrosis/physiopathology , Dry Powder Inhalers , Female , Humans , Lung/physiopathology , Male , Pseudomonas Infections/complications , Pseudomonas Infections/physiopathology , Tobramycin/administration & dosage , Young AdultABSTRACT
Abstract At present, the only approved inhaled antipseudomonal antibiotics for chronic pulmonary infections in patients with cystic fibrosis (CF) are nebulized solutions. However, prolonged administration and cleaning times, high administration frequency, and cumbersome delivery technologies with nebulizers add to the high treatment burden in this patient population. PulmoSphere™ technology is an emulsion-based spray-drying process that enables the production of light porous particle, dry-powder formulations, which exhibit improved flow and dispersion from passive dry powder inhalers. This review explores the fundamental characteristics of PulmoSphere technology, focusing on the development of a dry powder formulation of tobramycin for the treatment of chronic pulmonary Pseudomonas aeruginosa (Pa) infection in CF patients. This dry powder formulation provides substantially improved intrapulmonary deposition efficiency, faster delivery, and more convenient administration over nebulized formulations. The availability of more efficient and convenient treatment options may improve treatment compliance, and thereby therapeutic outcomes in CF.
