Efficacy, Safety, and Tolerability of ATM-AVI in the Treatment of Serious Infection Due to MBL-producing Gram-negative Bacteria

This is a prospective, randomized, multicenter, open-label, parallel group, comparative study to determine the efficacy, safety, and tolerability of aztreonam- avibactam (ATM- AVI) versus best available therapy (BAT) in the treatment of hospitalized adults with complicated intra-abdominal infections (cIAI), nosocomial pneumonia (NP) including hospital acquired pneumonia (HAP) and ventilator associated pneumonia (VAP), complicated urinary tract infections (cUTI), or bloodstream infections (BSI) due to metallo-β-lactamase (MBL)- producing Gram-negative bacteria. The study will randomize approximately 60 subjects in a 2:1 randomization scheme (ATM-AVI: BAT) with infections due to MBL-producing Gram-negative bacteria. Molecular testing at the central microbiology laboratory will be performed to confirm the MBL status of the organism upon study completion or at pre-designated intervals. The study will consist of a Screening Visit (Visit 1), a Baseline visit (Visit 2) on Day 1 of the study treatment, ongoing treatment visits (Visits 3 to 15) from Day 2 to Day 14, an End of Treatment (EOT) visit (Visit 16) within 24 hours after the last infusion, a Test of Cure (TOC) visit (Visit 17) on Day 28 (±3 days) and a Late Follow Up (LFU) visit (Visit 18) on Day 45 (±3 days). Subjects will be stratified at randomization based on infection type (cIAI, HAP/VAP, cUTI or BSI). The number of subjects with cUTI will be no more than approximately 75% of the study population. After obtaining written informed consent and confirming eligibility, subjects will be randomized in a 2:1 ratio to the ATM AVI treatment arm or the BAT treatment arm according to a central randomization schedule (approximately 40 (ATM AVI) and approximately 20 (BAT) subjects per group). The duration of treatment is 5 to 14 days for cIAI, cUTI and BSI and 7 to 14 days for HAP/VAP. Each subject is expected to complete the study, including the LFU visit. The precise duration of treatment will be determined by the investigator based on the subject's severity of infection and subsequent response to treatment. For subjects randomized to ATM AVI treatment arm, sparse blood samples will be collected for population pharmacokinetic (PK) assessments and PK/pharmacodynamic (PD) relationships will be evaluated in subjects where plasma samples and microbiological response data have been collected.