Aztreonam for inhalation solution (AZLI) in patients with cystic fibrosis, mild lung impairment, and P. aeruginosa

Background: Previous aztreonam for inhalation solution (AZLI) studies included patients with cystic fibrosis, Pseudomonas aeruginosa (PA) airway infection, and forced expiratory volume in 1 s (FEV(1)) 25% to 75% predicted. This double-blind, multicenter, randomized, placebo-controlled trial enrolled patients (>= 6 years) with FEV(1) >75% predicted. Methods: AZLI 75 mg (n=76) or placebo (n=81) was administered 3-times daily for 28 days with a 14-day follow-up. Results: Day 28 treatment effects were 1.8 points for CFQ-R-Respiratory Symptoms Scale (95%CI: -2.8, 6.4; p = 0.443; primary endpoint); -1.2 for log(10) sputum PA colony-forming units (p=0.016; favoring AZLI), and 2.7% for relative FEV(1)% predicted (p=0.021; favoring AZLI). Treatment effects favoring AZLI were larger for patients with baseline FEV(1) <90% predicted compared to >= 90% predicted. AZL1 was well-tolerated. Conclusions: Effects on respiratory symptoms were modest; however, FEV(1) improvements and bacterial density reductions support a possible role for AZLI in these relatively healthy patients. ClinicalTrials.gov identifier: NCT00712166. (C) 2011 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.