In vitro lung delivery of bacteriophages KS4-M and ΦKZ using dry powder inhalers for treatment of Burkholderia cepacia complex and Pseudomonas aeruginosa infections in cystic fibrosis.
OBJECTIVE
To determine the feasibility of formulating and aerosolizing powders containing bacteriophages KS4-M and ΦKZ for lung delivery and treatment of pulmonary Burkholderia cepacia complex and Pseudomonas aeruginosa infections.


RESULTS
Endotoxin-removed bacteriophages KS4-M and ΦKZ were lyophilized in lactose/lactoferrin 60 : 40 w/w matrix and deagglomerated in a mixer mill (without beads) to formulate respirable powders. The powders were then aerosolized using an Aerolizer(®) capsule inhaler. Mass median aerodynamic diameter (MMAD) of this inhalable aerosol was determined using Andersen cascade impactor at 60 l min(-1). Measured MMAD for both types of powders was 3·4 μm, and geometric standard deviation was 1·9-2·0. Viability of bacteriophages delivered distal to an idealized mouth-throat replica was determined from bioassays of samples collected on filters placed after the idealized replica. As a percentage of inhaler load, amount of powder delivered distal to the mouth-throat replica, which is a measure of lung delivery, was 33·7 ± 0·3% for KS4-M and 32·7 ± 0·9% for ΦKZ. Titres collected downstream of the mouth throat were (3·4 ± 2·5) × 10(6) PFU for KS4-M with an Aerolizer capsule load of (9·8 ± 4·8) × 10(6) and (1·9 ± 0·6) × 10(7) for ΦKZ with an Aerolizer capsule load of (6·5 ± 1·9) × 10(7).


CONCLUSIONS
Bacteriophages KS4-M and ΦKZ can be lyophilized without significant loss of viability in a lactose/lactoferrin 60 : 40 w/w matrix. The resulting powders can be aerosolized to deliver viable bacteriophages to the lungs.


CONCLUSIONS
Development of lactoferrin-based bacteriophage aerosol powders solidifies the ground for future research on developing novel formulations as an alternative to inhaled antibiotic therapy in patients with cystic fibrosis.
Golshahi
L
L
University of Alberta, Edmonton, AB, Canada.
Lynch
K H
KH
Dennis
J J
JJ
Finlay
W H
WH
D000336:Aerosols; D001435:Bacteriophages / Q000648:ultrastructure; D019121:Burkholderia Infections / Q000628:therapy*; D042602:Burkholderia cepacia complex; D003550:Cystic Fibrosis / Q000150:complications*; D058995:Dry Powder Inhalers; D005612:Freeze Drying; D006801:Humans; D007781:Lactoferrin / Q000032:analysis; D008168:Lung; D009330:Nebulizers and Vaporizers; D011552:Pseudomonas Infections / Q000628:therapy*; D011550:Pseudomonas aeruginosa
D000336:Aerosols; D007781:Lactoferrin