RESPIRE 1: a phase III placebo-controlled randomised trial of ciprofloxacin dry powder for inhalation in non-cystic fibrosis bronchiectasis

We evaluated the efficacy and safety of ciprofloxacin dry powder for inhalation (DPI) in patients with non-cystic fibrosis bronchiectasis, two or more exacerbations in the previous year and pre-defined bacteria in sputum. In this phase III, double-blind, placebo-controlled trial, patients were randomised 2: 1 to twice-daily ciprofloxacin DPI 32.5 mg or placebo in two treatment regimens consisting of on/off treatment cycles of 14 or 28 days for 48 weeks. The primary end-points were time to first exacerbation and frequency of exacerbations. A total of 416 patients were randomised to the 14-day on/off regimen (ciprofloxacin DPI (n=137) and placebo (n=68)) or the 28-day on/off regimen (ciprofloxacin DPI (n=141) and placebo (n=70)). Ciprofloxacin DPI 14 days on/off significantly prolonged time to first exacerbation versus pooled placebo (median time >336 versus 186 days; hazard ratio 0.53, 97.5% CI 0.36-0.80; p=0.0005) and reduced the frequency of exacerbations compared with matching placebo by 39% (mean number of exacerbations 0.6 versus 1.0; incidence rate ratio 0.61, 97.5% CI 0.40-0.91; p=0.0061). Outcomes for ciprofloxacin DPI 28 days on/off were not statistically significantly different from placebo. The safety profile of ciprofloxacin DPI was favourable. Ciprofloxacin DPI was well tolerated and has the potential to be an effective treatment option in non-cystic fibrosis bronchiectasis.