Assessment of Inflammatory Mediators (AIM)

Inclusion Criteria: Male or female 10 years of age or older. Confirmed diagnosis of CF based on the following criteria: positive sweat chloride >= 60 mEq/liter (by pilocarpine iontophoresis) and/or a genotype with two identifiable mutations consistent with CF, and accompanied by one or more clinical features consistent with the CF phenotype FEV1 >= 50% predicted value (subjects >= 10 - <18 years of age) or >= 40% predicted value (subjects >= 18 years of age) Clinically stable with no evidence of acute upper or lower respiratory tract infection or current pulmonary exacerbation within the 14 days prior to Visit 1 (Day 0) Ability to reproducibly perform spirometry and peak flow measurements Ability to understand and sign a written informed consent or assent and comply with the requirements of the study Exclusion Criteria: Use of an investigational agent within the 4-week period prior to Visit 1 (Day 0) Chronic daily use of ibuprofen, celecoxib, or other selective COX-2 inhibitors, other NSAIDs, or systemic or inhaled corticosteroids within the 4 weeks prior to Visit 1 (Day 0) or acute usage within 72 hours prior to Visit 1 (Day 0) History of hypersensitivity to beta-agonists History of hypersensitivity to sulfonamides, aspirin, or other NSAIDs Oxygen saturation < 92% on room air at Visit 1 (Day 0) Pregnant, breastfeeding, or unwilling to practice birth control during participation in the study History of hemoptysis >= 30 cc per episode during the 30 days prior to Visit 1 (Day 0) Significant history of hepatic, cardiovascular, renal, neurological, hematologic, or peptic ulcer disease SGOT (ALT) or SGPT (AST) > 3 times the upper limit of normal at screening, documented biliary cirrhosis, or portal hypertension Creatinine > 1.8 mg/dL at screening Inability to swallow pills Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the subject or the quality of the data