Late Breaking Abstract - Reduction in frequency of pulmonary exacerbations (PE) with inhaled ARD-3150 in non-cystic fibrosis bronchiectasis (NCFB) patients is independent of Pseudomonas aeruginosa (PA) susceptibility at baseline

Abstract

Background: Patients (pts) with NCFB and chronic PA may have resistant isolates owing to frequent antibiotic use. High inhaled antibiotic concentrations in sputum may overcome resistance. In a post-hoc analysis of ARD-3150 treated pts from 2 identical, randomized, placebo-controlled trials (ORBIT-3, O3; ORBIT-4, O4), reduction in PEs was investigated with respect to baseline susceptibility of PA isolates to ciprofloxacin (CIP). Methods: Pts enrolled in O3 and O4 had NCFB, chronic PA lung infection, ≥2 PEs requiring antibiotic treatment in the prior year and identification of at least one CIP non-resistant PA isolate at screening. Nebulized ARD-3150 (liposome-encapsulated CIP 150mg/3mL and free CIP 60mg/3mL) or placebo was administered once-daily for 6 cycles of 28 days on and 28 days off treatment for 48 weeks. The frequency of PEs in pts with PA isolates with CIP minimum inhibitory concentration (MIC) Results: At baseline, 148 pts in O3 and 177 pts in O4 had PA isolates with CIP MIC Conclusion: The observed PE frequency with once-daily inhaled ARD-3150 during the double blind treatment period was similar regardless of PA susceptibility to CIP at baseline.