A Phase 1b/2 Trial of the Safety and Microbiological Activity of Bacteriophage Therapy in Cystic Fibrosis Subjects Colonized With Pseudomonas Aeruginosa

This is a phase 1b/2, multicenter, randomized placebo-controlled double-blind study of a single dose of intravenous (IV) bacteriophage in males and non-pregnant females, at least 18 years old, diagnosed with Cystic Fibrosis (CF). This clinical trial is designed to assess the safety and microbiological activity of bacteriophage product Walter Reed Army Institute of Research- PAM-Cystic Fibrosis1 (WRAIR-PAM-CF1), directed at Pseudomonas aeruginosa (P. aeruginosa) in clinically stable CF individuals chronically colonized with P. aeruginosa. WRAIR-PAM-CF1 is a 4 component anti-pseudomonal bacteriophage mixture containing between 4 x 10\^7 and 4 x 10\^9 Plaque Forming Units (PFU) of bacteriophage. Enrollment will occur at up to 20 clinical sites in the United States. In stage 1, two sentinel subjects will be assigned to each of the three dosing arms receiving a single dosage of the IV bacteriophage therapy (4 x 10\^7 PFU, 4 x 10\^8 PFU, and 4 x 10\^9 PFU; total of 6 sentinel subjects), followed by 30 plus or minus 7 days observation period. If no Serious Adverse Events (SAEs) (related to the study product) are identified during the 96 hours after bacteriophage administration for all Sentinel Subjects in Stage 1, the study will proceed to Stage 2. In Stage 2a, 32 subjects will be enrolled into one of 4 arms (placebo IV, 4 x 10\^7 PFU, 4 x 10\^8 PFU, and 4 x 10\^9 PFU) in a 1:1:1:1 allocation. An interim analysis will be performed after all subjects have completed follow up visit 5 on Day 8+3 to select the IV bacteriophage dose with the most favorable safety and microbiological activity profile. During Stage 2b, subjects will be randomized into the bacteriophage (dose selected based on Interim Analysis following Stage 2a) or placebo arm. The final sample size is expected to be up to 72 subjects total with up to 25 subjects in the placebo arm and up to 25 subjects in the Stage 2b bacteriophage dose. The primary objectives of this study are to 1) describe the safety of a single dose of IV bacteriophage therapy in clinically stable CF subjects with P. aeruginosa in expectorated sputum; 2) describe the microbiological activity of a single dose of IV bacteriophage therapy in clinically stable CF subjects with P. aeruginosa in expectorated sputum; 3) describe the benefit to risk profile of a single dose of IV bacteriophage therapy in clinically stable CF subjects with P. aeruginosa in expectorated sputum.