The AIR-CF1 study was the pivotal trial for CAYSTON and assessed respiratory symptoms and lung function

Study Design chartStudy Design chart
  • AIR-CF11 (pivotal study) was a placebo-controlled trial that evaluated the efficacy and safety of CAYSTON.
  • AIR-CF22 was a placebo-controlled trial that contributed to the safety and microbiology profile for CAYSTON.
  • AIR-CF33 was an open-label follow-on trial that assessed the safety and microbiology profile for CAYSTON.

AIR-CF1: Study Design

AIR-CF1 was a Phase 3, double-blind, multicenter, international, randomized, placebo-controlled clinical trial of 164 patients >7 years old to evaluate CAYSTON in patients with CF and pulmonary Pseudomonas aeruginosa.

*1 course = 28 days on treatment, following 28 days off


  • Patients were randomized to receive 28 days of treatment with CAYSTON 75 mg or placebo 3 times a day.
  • All patients were required to take a dose of an inhaled bronchodilator (beta-agonist) prior to taking a dose of CAYSTON or placebo.
  • Patients received CAYSTON or placebo administered with the Altera® Nebulizer System.


  • Primary endpoint was improvement in respiratory symptoms on the last day of treatment as measured by the Respiratory Symptoms Scale of the Cystic Fibrosis Questionnaire-Revised (CFQ-R).1 Respiratory symptoms were also assessed 2 weeks after completion of treatment.
  • Secondary endpoint was the mean percent change in FEV1 (L).


  • Patients were required to have been off antibiotics for at least 28 days before treatment with study drug.
  • Patients were receiving standard care for CF, including drugs for obstructive airway diseases.

AIR-CF1: Baseline patient data (N=164)4

Mean age (SD)
30 (14) years
Age group
≥18 years
n=127 (77%)
<18 years
n=37 (23%)
% female
n=71 (43%)
Mean FEV1 % predicted (SD)
55% (14)
Disease severity
FEV1 >50% to ≤75% predicted
n=104 (63%)
FEV1 ≥25% to ≤50% predicted
n=60 (37%)
Mean tobramycin inhalation solution courses in previous 12 months (SD)
1.8 (2.2)
Baseline respiratory symptoms
Consistent with baseline disease