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

BackgroundPrevious aztreonam for inhalation solution (AZLI) studies included patients with cystic fibrosis, Pseudomonas aeruginosa (PA) airway infection, and forced expiratory volume in 1 s (FEV1) 25% to 75% predicted. This double-blind, multicenter, randomized, placebo-controlled trial enrolled patients (≥ 6 years) with FEV1 > 75% predicted.MethodsAZLI 75 mg (n = 76) or placebo (n = 81) was administered 3-times daily for 28 days with a 14-day follow-up.ResultsDay 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 log10 sputum PA colony-forming units (p = 0.016; favoring AZLI), and 2.7% for relative FEV1% predicted (p = 0.021; favoring AZLI). Treatment effects favoring AZLI were larger for patients with baseline FEV1 < 90% predicted compared to ≥ 90% predicted. AZLI was well-tolerated.ConclusionsEffects on respiratory symptoms were modest; however, FEV1 improvements and bacterial density reductions support a possible role for AZLI in these relatively healthy patients. ClinicalTrials.gov identifier: NCT00712166.