Oral Presentation Australian Society for Microbiology Annual Scientific Meeting 2019

Inhaled bacteriophage and endolysin therapy for respiratory infections (#80)

Hak-Kim Chan 1
  1. Advanced Drug Delivery Group, School of Pharmacy, University of Sydney, Sydney, NSW, Australia

Emergence of multidrug resistant (MDR) bacteria is causing a global medical challenge for treatment of respiratory infections. Inhaled bacteriophage (phage) and inhaled endolysin therapies are promising alternative treatment option that is gaining a renewed and increasing amount of attention for its ability to eradicate MDR bacteria. Biologics such as phages and endolysins can be delivered as aerosols using nebulizers (liquid formulations) or dry powder inhalers (dry powder formulations). Phage PEV20 was formulated in inhalable dry powders by spray drying the phages with suitable excipients, including lactose and leucine. Our PEV20 phage powder provided efficacious anti-Pseudomonal activities against clinical MDR isolate in a mouse lung infection model. Furthermore, the safety of phage powder formulation was validated using resazurin assay and histopathological examination in vitro and in vivo, respectively. This phage powder remained physically and biologically stable after one year of storage at ambient conditions. In a separate study, we assessed the aerosol performance and in vitro efficacy of nebulized endolysin Cpl-1 against Streptococcus pneumoniae. Vibrating mesh nebulizer maintained the antimicrobial activity of CpI-1, whereas air-jet nebulizer caused significant loss. Both nebulizers generated aerosol particles suitable for inhalation delivery. These two studies demonstrated the potential use of inhaled phages and endolysin for treatment of bacterial respiratory infections.