Ease of Use and Microbial Contamination of Tobramycin Inhalation Powder (TIP) Versus Nebulised Tobramycin Inhalation Solution (TIS) and Nebulised Colistimethate (COLI)

Key Inclusion Criteria: * Provide written informed consent, HIPAA authorization, and assent (as appropriate for minors) prior to the performance of any study-related procedure * Confirmed diagnosis of Cystic Fibrosis (CF) * Male and female patients 6 years of age or older at screening * Forced Expiratory Volume in 1 second (FEV1) at screening (Visit 1) must be at least 25% and less than or equal to 90% of normal predicted values for age, sex, and height based on the NHANES III values (Hankinson, 1999) for patients 18 years of age or greater, and based on values from Wang (Wang 1993) for patients less than 18 years of age. * Documented use of any of the nebulized antibiotics based on local practice: * Tobramycin Inhalation Solution, colistimethate, or Tobramycin Inhalation Powder for at least 1 cycle within the last 6 months or * Colistimethate continuous use for at least 8 weeks within the last 6 months This cycle of treatment (or continuous colistimethate treatment period) is in addition to the treatment cycle during which the subject is being screened. * P. aeruginosa must be present in a sputum or deep cough throat swab culture or bronchoalveolar lavage (BAL) (only for BAL a threshold level of 10\^3 CFU/mL is required) within 6 months prior to screening, and in the sputum or deep cough throat swab culture at screening or rescreening (Visit 1); Key Exclusion Criteria: * History of sputum culture or deep cough throat swab (or BAL) culture yielding Burkholderia cenocepacia…