Primary end-points: time to first exacerbation and frequency of exacerbations# in patients treated with ciprofloxacin dry powder for inhalation (DPI) versus placebo over 48 weeks
| Primary end-point | HR or IRR¶ (95.1% or 99.9% CI+) | p-value (Wald-type test) |
| Time to first exacerbation | ||
| Ciprofloxacin DPI 14 days on/off versus pooled placebo | 0.8662 (0.62–1.21) | 0.3965 |
| Ciprofloxacin DPI 28 days on/off versus pooled placebo | 0.7062 (0.39–1.27) | 0.0511 |
| Frequency of exacerbations | ||
| Ciprofloxacin DPI 14 days on/off versus matching placebo | 0.8313 (0.59–1.17) | 0.2862 |
| Ciprofloxacin DPI 28 days on/off versus matching placebo | 0.5493 (0.30–1.02) | 0.0014 |
HR: hazard ratio; IRR: incidence rate ratio. #: for the primary end-points, an exacerbation (stringent definition) was required to meet three criteria: 1) worsening in at least three signs or symptoms (dyspnoea, wheezing, cough, 24-h sputum volume or sputum purulence) beyond normal day-to-day variation for at least 2 consecutive days, 2) fever (body temperature >38.0°C) or malaise/fatigue, and 3) systemic antibiotic treatment; ¶: HRs were calculated for time to first exacerbation; IRRs were calculated for frequency of exacerbations; +: the confidence interval is 95.1% for comparisons of ciprofloxacin DPI 14 days on/off versus placebo and 99.9% for comparisons of ciprofloxacin DPI 28 days on/off versus placebo.