Subjects must meet all of the below inclusion criteria to be eligible to participate in the study:

• Adult (>/= 18 years) at the time of screening.
  
• Confirmed CF diagnosis based on a compatible clinical syndrome confirmed by either an abnormal sweat chloride testing or two CFTR gene variations. (Can be obtained from documentation in medical records; actual test results not necessary.)
• Readily able to produce at least 2 mL of sputum during a 30-minute sputum collection following a hypertonic saline treatment or other approach to increase sputum production. (Determined by investigator or their designee judgment. Approaches for obtaining sputum may include, but are not limited to, inhaled hypertonic saline (e.g. 3%, 7%, or 10%), inhaled hypertonic bicarbonate, inhaled mannitol, or spontaneously expectorated sputum. The same approach should be used for all sputum collections for a given subject, refer to the MOP for further details.)
• P. aeruginosa (regardless of Colony Forming Units (CFU)/mL) isolated from a sputum, throat culture, or other respiratory specimen in the past 12 months.
• Confirmed P. aeruginosa isolation from a sample of expectorated sputum at the screening visit.
• Capable of providing informed consent.
• Capable and willing to complete all study visits and perform all procedures required by this protocol.

Subjects who meet any of the below exclusion criteria will not be enrolled in the study:

• Body weight < 30 kg.
• Forced Expiratory Volume 1< 20% of predicted value at screening, using the Hankinson equations.25
• Elevated LFTs obtained at screening. (a. Alanine aminotransferase (ALT) > 5 x the upper limit of normal (ULN) or aspartate transaminase (AST) > 5 x ULN or total bilirubin > 3 x ULN, OR b. Total bilirubin > 1.5 x ULN combined with either ALT > 3 x ULN or AST > 3 x ULN. ULN reflect local laboratory ranges.)
• Acute clinical illness requiring a new (oral, parenteral), or inhaled antibiotic(s) = 30 days prior to the baseline visit. (Does not include chronic suppressive medications or cyclic dosing medications such as inhaled antibiotics.)
• Women who are pregnant, planning to become pregnant during the study period, or breastfeeding. (Women of childbearing potential must have a negative serum Beta-Human chorionic gonadotropin test during screening and agree to use an effective method of contraception for the duration of the trial.
• A female is considered of childbearing potential unless postmenopausal, or surgically sterilized and at least 3 months has passed since sterilization procedure.)
• Female surgical sterilization procedures include tubal ligation, bilateral salpingectomy, hysterectomy, or bilateral oophorectomy
• Female is considered postmenopausal if she is >45 years old and has gone at least 12 months without a spontaneous menstrual period without other known or suspected cause.
• Effective methods of contraception include (a) abstinence, (b) partner vasectomy, (c) intrauterine devices, (d) hormonal implants (such as Implanon), or (e) other hormonal methods (birth control pills, injections, patches, vaginal rings).
• Active treatment of any nontuberculous mycobacteria or fungal organisms </=30 days prior to baseline. Chronic treatment for suppression of fungal populations is allowable.
• Anticipated need to change chronic antibiotic regimens during the study period. (Subjects on cyclic dosing medications such as inhaled antibiotics, must be able and express willingness to keep the therapies at the time of screening constant for the duration of the follow-up period (approximately 30 days). Subjects on chronic suppressive antimicrobial therapy must be able and express willingness to stay on the therapies for the duration of their follow-up period. This includes chronic azithromycin therapy.)
• Known allergy to any component of the study product.
• Any significant finding that, in the opinion of the investigator, would make it unsafe for the subject to participate in this study.
  
• Enrolled in a clinical trial within </=30 days of the baseline/dosing visit, or participating in a clinical trial while enrolled in this clinical trial (inclusive of prophylactic vaccine trials).
• Currently or previously enrolled in this trial.
  

California

Colorado

• National Jewish Health - Division of Pulmonary, Critical Care and Sleep Medicine; Denver, Colorado, United States, 80206

Florida

• University of South Florida Health - Internal Medicine; Tampa, Florida, United States, 33606
  

Georgia

• Emory University - Woodruff Health Sciences Center; Atlanta, Georgia, United States, 30324

Iowa

• University of Iowa Hospitals & Clinics - Department of Internal Medicine; Iowa City, Iowa, United States, 52242
  

Maryland            

• Johns Hopkins Children's Center - Pediatric Infectious Diseases    ; Baltimore, Maryland, United States, 21287-0011
  

Michigan

• University of Michigan - Infectious Disease Clinic at Taubman Center; Ann Arbor, Michigan, United States, 48109
  

Minnesota

• University of Minnesota - Pediatric Infectious Disease; Minneapolis, Minnesota, United States, 55455-0341
• University of Minnesota Medical Center, Fairview - Infectious Diseases and International Medicine; Minneapolis, Minnesota, United States, 55455-0341
  

Missouri              

• Washington University in St. Louis; Saint Louis, Missouri, United States, 63110-1010
  

North Carolina  

• Duke University School of Medicine - Duke Clinical Research Institute - Duke Clinical Research Unit; Durham, North Carolina, United States, 27701
  

Ohio

• Case Western Reserve University School of Medicine - Medicine - Infectious Diseases and HIV Medicine; Cleveland, Ohio, United States, 44106
  

Pennsylvania

• Children's Hospital of Pittsburgh of UPMC - Allergy, Immunology and Infectious Diseases; Pittsburgh, Pennsylvania, United States, 15213
  

Texas

• University of Texas Southwestern Medical Center - Internal Medicine - Infectious Diseases; Dallas, Texas, United States, 75390-8884
  

Wisconsin           

• Medical College of Wisconsin; Milwaukee, Wisconsin, United States, 53226
  

Brief Summary from Clinicaltrials.gov:

This clinical trial is designed to assess the safety and microbiologic activity of bacteriophage product WRAIR_PAM-CF1, directed at Pseudomonas aeruginosa in clinically stable CF individuals. WRAIR_PAM-CF1 is a 4 component anti-pseudomonal bacteriophage containing between >/= 4 x 10^7 and >/= 4 x 10^9 Plaque Forming Units (PFU) in the target dose.

In stage 1, two eligible 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 a 96-hour observation period.

Stage 2a will proceed if no serious adverse events (SAEs) related to the study product occur during the observation period of stage 1; 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 after all subjects have completed follow up visit 5 on Day 30 will be performed to select an IV bacteriophage dose with the most favorable safety and microbiologic 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.

If you believe you are eligible for this study, and would like to be screened for enrollment, please reach out to the cystic fibrosis center at the trial site nearest you.

You can search https://www.clinicaltrials.gov/ for other clinical trials for which you may be eligible. We also expect additional phage therapy clinical trials in the future, so you are welcome to check our website periodically for future trial announcements.