Study With Phage for CF Subjects With Pseudomonas Lung Infection

Key Inclusion Criteria:

* Cystic fibrosis patients with chronic Pseudomonas aeruginosa pulmonary infection receiving standard of care inhaled antibiotics (cycling or continuous regimen) or no inhaled antibiotics
* Age ≥ 18 years
* FEV1 40%-80% predicted
* Clinically stable lung disease
* Willing and able to provide adequate sputum samples, using any method (spontaneously expectorated, induced, from home or clinic) at designated study visits.

Key Exclusion Criteria:

* Known hypersensitivity to bacteriophages or excipients in the formulation.
* Receipt of prior bacteriophage therapy within the 6 months prior to Screening or Day 1
* Detection of Burkholderia cenocepacia from respiratory tract within 1 year prior to Screening or from Screening culture
* Currently receiving systemic treatment for allergic bronchopulmonary aspergillosis
* Currently receiving treatment for active infection with non-tuberculous mycobacteria or prior detection of Mycobacterium abscessus in 12 months prior to Screening
* History of severe neutropenia
* History of lung transplant
* History of solid organ transplant
* Acquired or primary immunodeficiency syndrome
* Initiation or change in type of CFTR modulator less than 3 months prior to Screening
* Pregnant or breastfeeding female