Azithromycin for Early Pseudomonas Infection in Cystic Fibrosis. The OPTIMIZE Randomized Trial

Rationale: New isolation of Pseudomonas aeruginosa (Pa) is generally treated with inhaled antipseudomonal antibiotics such as tobramycin inhalation solution (TIS). A therapeutic approach complementing traditional antimicrobial therapy by reducing the risk of pulmonary exacerbation (PEx) and inflammation may ultimately prolong time to Pa recurrence. Objectives: To test the hypothesis that the addition of azithromycin to TIS in children with CF and early Pa decreases the risk of PEx and prolongs time to Pa recurrence. Methods: The OPTIMIZE trial was a multicenter, double-blind, randomized, placebo-controlled, 18-month trial in children with CF ages 6 months-18 years with early Pa. Azithromycin or placebo was given 3x weekly with standardized TIS. Measurements: The primary endpoint was time to PEx requiring antibiotics and secondary endpoint time to Pa recurrence, in addition to other clinical and safety outcomes. Main Results: 221 participants (111 placebo, 110 azithromycin) out of a planned 274 were enroll...