Early Methicillin-resistant Staphylococcus Aureus (MRSA) Therapy in Cystic Fibrosis (CF)

Inclusion Criteria

• •1. Male or female ≥ 4 and ≤ 45 years of age at the Screening Visit.
• •2. Documentation of a CF diagnosis as evidenced by one or more clinical features consistent with the CF phenotype and one or more of the following criteria:
• •* sweat chloride ≥ 60 mEq/liter by quantitative pilocarpine iontophoresis test (QPIT)
• •* two well-characterized mutations in the cystic fibrosis transmembrane conductive regulator (CFTR) gene
• •* Abnormal nasal potential difference (change in NPD in response to a low chloride solution and isoproteronol of less than -5 mV)
• •3. First OR early repeat MRSA colonization defined as:
• •* First MRSA colonization: first documented isolation of MRSA from respiratory tract occurred ≤ 6 months prior to screening
• •* OR Early repeat MRSA colonization:
• •MRSA was previously isolated from the respiratory tract (≤ 2 times), but this was followed by at least 1 year of documented negative cultures for MRSA as noted below:
• •\-- At least 2 cultures performed at least 3 months apart to document 1 year of culture negativity. Each of these cultures should be documented to have been collected at least 1 week after end of any antibiotic prescription with MRSA activity.
• •Patient again recently positive for MRSA from the respiratory tract (within 6 months prior to screening)
• •4. Clinically stable with no significant changes in health status within the 14 days prior to screening
• •5. Written informed consent (and assent when applicable) obtained from subject or subject's legal representative and ability for subject to comply with the requirements of the study
• •A repeat culture from the respiratory tract is obtained at screening but does not have to be positive to be able to enter the study.