title: Microparticles for inhalational delivery of antipseudomonal antibiotics.
abstract: Chronic pseudomonal bronchopulmonary infections in cystic fibrosis patients are frequently controlled with inhaled antibiotics. Dry-powder inhalable antibiotics are an attractive alternative to nebulized medications. We produced and evaluated microparticles composed of dipalmitoylphosphatidylcholine, albumin, and lactose as a model system for intrapulmonary delivery of ceftazidime, ciprofloxacin, and several combinations of the two, none of which is presently available for inhalation. Microparticles containing one or both antibiotics were prepared by spray-drying. Their Anderson cascade impactor deposition profiles showed 10-30% fine particle fractions of the nominal dose. Microparticles containing varying amounts of each antibiotic showed statistically different deposition profiles. Aerodynamics and deposition of microparticles co-encapsulating both antibiotics were similar to those of single-drug microparticles with the same proportion of ciprofloxacin alone. The antipseudomonal activities of microparticles co-encapsulating half of the 50% effective concentration (EC(50)) of both ceftazidime and ciprofloxacin (5 mg of particles containing 5% ceftazidime and 10% ciprofloxacin) were at least additive compared to particles containing the EC(50) of each antibiotic separately (5 mg of particles containing 10% ceftazidime or 5 mg of particles containing 20% ciprofloxacin). Co-encapsulation of the antibiotics in microparticles ensures co-deposition at desired ratios, improves the particles' aerodynamics and fine particle fraction, as compared to microparticles with equivalent amounts of ceftazidime alone, and achieves additive antipseudomonal activity.
authors.affiliation: Department of Pediatrics, Division of Pediatric Intensive Care Medicine, Lutheran General Children's Hospital, 1775 Dempster St., Park Ridge, Illinois, 60068, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Tsifansky
authors.forename: Yoon
authors.initials: Y
authors.lastname: Yeo
authors.forename: Oleg V
authors.initials: OV
authors.lastname: Evgenov
authors.forename: Evangelia
authors.initials: E
authors.lastname: Bellas
authors.forename: John
authors.initials: J
authors.lastname: Benjamin
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Kohane
mesh_terms: D000280:Administration, Inhalation; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D001991:Bronchitis / Q000188:drug therapy; D002442:Ceftazidime / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid; D002939:Ciprofloxacin / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D004337:Drug Carriers / Q000737:chemistry; D004338:Drug Combinations; D006801:Humans; D008855:Microscopy, Electron, Scanning; D009330:Nebulizers and Vaporizers; D010316:Particle Size; D018410:Pneumonia, Bacterial / Q000188:drug therapy; D011552:Pseudomonas Infections / Q000188:drug therapy; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013499:Surface Properties
chemical_list: D000900:Anti-Bacterial Agents; D004337:Drug Carriers; D004338:Drug Combinations; D002939:Ciprofloxacin; D002442:Ceftazidime