The primary objective of this study is to evaluate the safety and tolerability of a single dose of KB001 in Cystic Fibrosis patients infected with Pseudomonas aeruginosa (Pa)

CF patients often have lung infections. Pseudomonas aeruginosa (Pa) is the most significant bacteria in CF, with up to 80% of CF patients eventually becoming infected. These patients are often treated with antibiotics with variable results. This study will examine the impact of a single-dose of an investigational drug, KB001, on Pa bacteria in the CF lung.

Inclusion Criteria:

• Written informed consent
• Confirmed diagnosis of CF based on the following criteria:

Positive sweat chloride greater than 60mEq/liter, and/or a genotype with 2 identifiable mutations consistent with CF, and one or more clinical features consistent with the CF phenotype

• Age >/= 18 years of age with the potential for age 12 >/=
• Screening Pa sputum culture
• FEV1% predicted >/= 40 (based on Wang's equations for Males aged 12-17 and females 12-15 years, and Hankinson's equations for all other patients)

Exclusion Criteria:

• Evidence of an acute respiratory infection or pulmonary exacerbation within 4 weeks prior to day 0
• Use of systemic corticosteroids or antibiotics within 4 weeks prior to day 0, or cyclic inhaled antibiotics within 14 days prior to day 0.
• History of positive B. cepacia complex, organ transplantation, hepatic disease or venal dysfunction
• Current cigarette smoker, history of drug addiction or alcohol abuse
• Use of investigational medication or participation in an investigational study within 4 weeks prior to day 0
• Women who are pregnant or breastfeeding and patients and/or partner unwilling to use an effective form of barrier contraception throughout the study