Inclusion Criteria:  Male or female >18 years of age Participant must have a diagnosis of an infection (HAP/VAP, cUTI, cIAI, BSI) due to confirmed carbapenem-resistant aerobic Gram-negative pathogens, requiring administration of IV antibacterial therapy Participant who had received appropriate prior empiric antibacterial therapy for a carbapenem-resistant pathogen must meet at least 1 of the following criteria: no or no more than 24h; worsening of objective symptoms or signs after at least 48 hours of antibacterial therapy; no change of objective symptoms or signs after at least 72 hours of antibacterial therapy. Capable of giving signed informed consent  Exclusion Criteria:  Other medical or psychiatric condition may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study. Participant is expected to require more than 21 days of treatment Participants who need more than 3 systemic antibiotics as part of best available treatment (BAT) Previous administration with an investigational drug within 30 days or 5 half lives preceding the first dose of study intervention used in this study (whichever is longer). Participant is pregnant or breastfeeding. Acute Physiology and Chronic Health Evaluation (APACHE) II score >30 or <10 using the most recent available data.