Study design (if review, criteria of inclusion for studies)
Randomized controlled trial. Multicenter trial in the United States. Intention-to-treat analysis
Participants
304 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.
Outcome measures
exacerbation rates, P aeruginosa- positive culture. Adverse events
Main results
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.
Authors' 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.