The purpose of this study is to evaluate an investigational drug called AP-PA02 as a possible treatment for individuals with cystic fibrosis (CF) and chronic pulmonary Pseudomonas aeruginosa (Pa) infection. There are 2 main parts to this study, Part 1 and Part 2. If you choose to take part in the study, whether you enroll in Part 1 or Part 2 will be determined by which part is ongoing at the time you enroll. The goals for both parts are to learn how safe the study drug is and how well it is tolerated compared with placebo when used 1 or more times at different doses. For both Part 1 and Part 2, the study is divided into 4 time periods: a screening period, a baseline period, a treatment period, and a follow-up period. During the screening period, you will be at the study center for approximately 3-4 hours. The screening procedures and tests may be done over more than one day if needed. The baseline visit will last approximately 3-4 hours. On days you receive treatment with the study drug, your visit will last approximately 9-10 hours. Your doctor will follow you for several weeks after study drug administration. Follow-up visits will last between 2 and 4 hours, depending on procedures required at each visit. Maximum reimbursement for completion of all study visits up to $3,720.

You may be eligible for this study if you meet the following criteria:

• Conditions: Cystic Fibrosis,Pulmonary Pseudomonas aeruginosa
• Age: 18 years - 99 years
• Gender: All