Comparative efficacy and safety of 4 randomized regimens to treat early Pseudomonas aeruginosa infection in children with cystic fibrosis

Objective: To investigate the efficacy and safety of 4 antipseudomonal treatments in children with cystic fibrosis with recently acquired Pseudomonas aeruginosa infection. Design: Randomized controlled trial. Setting: Multicenter trial in the United States. Participants: Three hundred four children with cystic fibrosis aged 1 to 12 years within 6 months of P aeruginosa detection. Interventions: Participants were randomized to 1 of 4 antibiotic regimens for 18 months (six 12-week quarters) between December 2004 and June 2009. Participants randomized to cycled therapy received tobramycin inhalation solution (300 mg twice a day) for 28 days, with oral ciprofloxacin (15-20 mg/kg twice a day) or oral placebo for 14 days every quarter, while participants randomized to culture-based therapy received the same treatments only during quarters with positive P aeruginosa cultures. Main Outcome Measures: The primary end points were time to pulmonary exacerbation requiring intravenous antibiotics and proportion of P aeruginosa - positive cultures. Results: The intention-to-treat analysis included 304 participants. There was no interaction between treatments. There were no statistically significant differences in exacerbation rates between cycled and culture-based groups (hazard ratio, 0.95; 95% confidence interval [CI], 0.54-1.66) or ciprofloxacin and placebo (hazard ratio, 1.45; 95% CI, 0.82-2.54). The odds ratios of P aeruginosa - positive culture comparing the cycled vs culture-based group were 0.78 (95% CI, 0.49-1.23) and 1.10 (95% CI, 0.71-1.71) comparing ciprofloxacin vs placebo. Adverse events were similar across groups. Conclusions: No difference in the rate of exacerbation or prevalence of P aeruginosa positivity was detected between cycled and culture-based therapies. Adding ciprofloxacin produced no benefits. Trial Registration: ClinicalTrials.gov Identifier: NCT00097773.