Safety, tolerability and pharmacokinetics following repeated doses (15-day dosing)

Inclusion Criteria:

• Male or female ≥ 6 years (pediatric 6 - 17 years inclusive; adult ≥ 18 years); minimum weight requirement of 20 kg
• Confirmed diagnosis of CF (positive sweat chloride ≥ 60 milliequivalents (mEq)/liter (by pilocarpine iontophoresis) and/or a genotype with two identifiable mutations consistent with CF accompanied by one or more clinical features with the CF phenotype
• Forced expiratory volume in one second (FEV1) > 25% predicted (using prediction equation's of Knudson et al)
• Clinically stable with no evidence of acute upper or lower respiratory tract infection or current pulmonary exacerbation within 2 weeks of screening
• Females of child bearing potential must have a negative pregnancy test at screening and, if sexually active, must be willing to use a double-barrier form of contraception for the duration of the study
• The patient or the patient's legally acceptable representative must be able to give informed consent in accordance with International Conference on Harmonization (ICH) Good Clinical Practice (GCP) guidelines and local legislation
• The patient must be able to swallow the BIIL 284 tablet whole
• Patients taking a chronic medication must be willing to continue this therapy for the entire duration of the study

Exclusion Criteria:

• Patients with a history of allergy/hypersensitivity (including medication allergy) which is deemed relevant to the trial as judged by the Investigator
• Patients who have participated in another study with an investigational drug (including BI Trial 543.36) within one month or 6 half-lives (whichever is greater) preceding the screening visit
• Patients with known substance abuse, including alcohol or drug abuse, within 30 days prior to screening
• Female patients who are pregnant or lactating
• Patients who are unable to comply with breakfast requirements prior to dosing
• Patients who have received IV, oral or inhaled antibiotics or corticosteroids for a pulmonary exacerbation within 2 weeks of screening
• Patients who have started a new chronic medication for CF within 2 weeks of screening
• Patients with documented persistent colonization with B. cepacia (defined as more than one positive culture within the past year)
• Patients with clinically significant findings on chest x-ray which in the opinion of the Investigator precludes the patient's participation in the trial
• Patients with oxyhemoglobin saturation in room air < 90% by pulse oximetry
• Patients with hemoglobin < 9.0 g/dL; platelets < 100x10**9/L; prothrombin time (PT) > 1.5 times the upper limit of normal, serum glutamic-oxaloacetic transaminase (ALT) or serum glutamic-pyruvic transaminase (AST) > 2 times the upper limit of normal; creatinine > 1.8 mg/dL (adults) or > 1.4 mg/dL (pediatrics) at screening
• Clinically significant disease or medical condition other than CF or CF-related conditions that, in the opinion of the Investigator, would compromise the safety of the patient or the quality of the data. This includes significant hematological, hepatic, renal, cardiovascular, and neurologic disease. Patients with diabetes may participate if their disease is under good control prior to screening.