Efficacy and Safety Study of AeroVanc for the Treatment of Persistent MRSA Lung Infection in Cystic Fibrosis Patients

This is a Phase 2a randomized, multicenter, double-blind, placebo-controlled, parallel group study to examine the safety and efficacy of AeroVanc in the treatment of persistent MRSA lung infection in CF patients. Pharmacokinetics will be evaluated in a subgroup by measuring plasma and sputum concentrations of vancomycin. Prior to treatment, patients will be randomized to receive either AeroVanc twice daily (bid), or placebo bid. Patients will be stratified based on the presence of a Pseudomonas aeruginosa (P. aeruginosa) co-infection that is being treated with a chronic suppression regimen. Patients with P. aeruginosa co-infection can be on any chronic inhaled suppression regimen (or nothing if the patient is considered stable in the opinion of the investigator despite the lack of treatment). Regardless of treatment regimen, if there is an off month, screening should be scheduled so that AeroVanc or placebo administration can be given during this time. Patients with no off month should be screened so that the AeroVanc or placebo administration period coincides with a treatment cycle other than TOBI (e.g., Cayston or colistin). All patients must have at least a 24-hour washout period after stopping their anti-Pseudomonas therapy and prior to the Visit 2 (Baseline) pre-dose microbiology sputum sample. The AeroVanc or placebo treatment duration is 28 days, during which efficacy and safety parameters will be measured, and after which patients will be followed up for 56 days. There will be two treatment cohorts in this study, each comprised of 40 randomized (1:1 active to placebo) and treated patients (adults ≥18 and children ≥12 years of age). In Cohort 1, patients will be enrolled and randomized to receive the 32 mg dose of AeroVanc bid or placebo bid. Prior to starting enrollment in Cohort 2, a safety evaluation will be carried out by the Data Monitoring Committee (DMC) based on treatment data from the first 20 patients in Cohort 1. Subject to the Sponsor's written communication of the DMC's opinion of acceptable safety, the dose for the active arm in Cohort 2 will be escalated to 64 mg bid. Optionally, the active arm for Cohort 2 may also be kept the same (32 mg bid), or reduced to 16 mg bid, depending on the outcome of the DMC's safety evaluation.