Trial Outcomes & Findings for A Study to Determine the Efficacy, Safety and Tolerability of Aztreonam-Avibactam (ATM-AVI) ± Metronidazole (MTZ) Versus Meropenem (MER) ± Colistin (COL) for the Treatment of Serious Infections Due to Gram Negative Bacteria. (NCT NCT03329092)

Results Overview

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% confidence interval (CI) was based on Jeffrey's method.

Recruitment status

COMPLETED

Study phase

PHASE3

Target enrollment

422 participants

Primary outcome timeframe

At TOC visit (Day 28)

Results posted on

2024-12-10

Participant Flow

Participants who were hospitalized with a diagnosis of complicated intra-abdominal infection (cIAI) or nosocomial pneumonia (NP) including hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) were enrolled. This study was conducted across 20 countries from 05-Apr-2018 to 23-Feb-2023.

A total of 461 participants were screened of which 38 failed screening and 1 participant was not randomized due to lack of study drug at the site. A total of 422 participants were randomized in the study.

Participant milestones

Participant milestones
Measure	Aztreonam-avibactam ± Metronidazole Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Overall Study STARTED	282	140
Overall Study Participants With cIAI	208	104
Overall Study Participants With HAP/VAP	74	36
Overall Study COMPLETED	242	122
Overall Study NOT COMPLETED	40	18

Reasons for withdrawal

Reasons for withdrawal
Measure	Aztreonam-avibactam ± Metronidazole Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Overall Study Other	2	2
Overall Study Withdrawal by Subject	16	3
Overall Study Physician Decision	1	0
Overall Study Death	17	11
Overall Study Adverse Event	3	1
Overall Study Lost to Follow-up	1	1

Baseline Characteristics

A Study to Determine the Efficacy, Safety and Tolerability of Aztreonam-Avibactam (ATM-AVI) ± Metronidazole (MTZ) Versus Meropenem (MER) ± Colistin (COL) for the Treatment of Serious Infections Due to Gram Negative Bacteria.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.	Total n=422 Participants Total of all reporting groups
Age, Continuous	55.2 Years STANDARD_DEVIATION 17.84 • n=5 Participants	54.0 Years STANDARD_DEVIATION 16.30 • n=7 Participants	54.8 Years STANDARD_DEVIATION 17.33 • n=5 Participants
Sex: Female, Male Female	96 Participants n=5 Participants	39 Participants n=7 Participants	135 Participants n=5 Participants
Sex: Female, Male Male	186 Participants n=5 Participants	101 Participants n=7 Participants	287 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	58 Participants n=5 Participants	21 Participants n=7 Participants	79 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	213 Participants n=5 Participants	113 Participants n=7 Participants	326 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	11 Participants n=5 Participants	6 Participants n=7 Participants	17 Participants n=5 Participants
Race/Ethnicity, Customized White	164 Participants n=5 Participants	64 Participants n=7 Participants	228 Participants n=5 Participants
Race/Ethnicity, Customized Black or African American	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Race/Ethnicity, Customized Asian	107 Participants n=5 Participants	69 Participants n=7 Participants	176 Participants n=5 Participants
Race/Ethnicity, Customized American Indian or Alaska Native	7 Participants n=5 Participants	2 Participants n=7 Participants	9 Participants n=5 Participants
Race/Ethnicity, Customized Mixed	2 Participants n=5 Participants	1 Participants n=7 Participants	3 Participants n=5 Participants
Race/Ethnicity, Customized Other	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Race/Ethnicity, Customized Not reported	1 Participants n=5 Participants	2 Participants n=7 Participants	3 Participants n=5 Participants

PRIMARY outcome

Timeframe: At TOC visit (Day 28)

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% confidence interval (CI) was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at Test of Cure (TOC) Visit: Intent-To-Treat (ITT) Analysis Set	68.4 Percentage of participants Interval 62.8 to 73.7	65.7 Percentage of participants Interval 57.6 to 73.2

PRIMARY outcome

Timeframe: At TOC visit (Day 28)

Population: Analysis was performed on CE analysis set.

Clinical cure = improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method. CE analysis set:all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=213 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=105 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at TOC Visit: Clinically Evaluable (CE) Analysis Set	77.0 Percentage of participants Interval 71.0 to 82.3	74.3 Percentage of participants Interval 65.3 to 81.9

SECONDARY outcome

Timeframe: At TOC visit (Day 28)

Population: The microbiological Intent-To-Treat (micro-ITT) analysis set was a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at TOC Visit: Microbiological Intent-To-Treat (Micro-ITT) Analysis Set	72.9 Percentage of participants Interval 66.0 to 79.0	72.3 Percentage of participants Interval 62.7 to 80.6

SECONDARY outcome

Timeframe: At TOC visit (Day 28)

Population: ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at TOC Visit: Microbiologically Evaluable (ME) Analysis Set	78.5 Percentage of participants Interval 71.4 to 84.5	75.9 Percentage of participants Interval 65.7 to 84.3

SECONDARY outcome

Timeframe: At TOC visit (Day 28)

Population: ITT analysis set included all randomized participants regardless of receipt of study drug. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at TOC Visit by Type of Infection: ITT Analysis Set cIAI	76.4 Percentage of participants Interval 70.3 to 81.8	74.0 Percentage of participants Interval 65.0 to 81.7
Percentage of Participants With Clinical Cure at TOC Visit by Type of Infection: ITT Analysis Set HAP/VAP	45.9 Percentage of participants Interval 34.9 to 57.3	41.7 Percentage of participants Interval 26.7 to 57.9

SECONDARY outcome

Timeframe: At TOC visit (Day 28)

Population: CE analysis set. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure = improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method. CE analysis set:all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=213 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=105 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at TOC Visit by Type of Infection: CE Analysis Set cIAI	85.1 Percentage of participants Interval 79.2 to 89.9	79.5 Percentage of participants Interval 69.9 to 87.1
Percentage of Participants With Clinical Cure at TOC Visit by Type of Infection: CE Analysis Set HAP/VAP	46.7 Percentage of participants Interval 32.7 to 61.1	54.5 Percentage of participants Interval 34.3 to 73.7

SECONDARY outcome

Timeframe: At TOC visit (Day 28)

Population: Micro-ITT analysis set was a subset of the ITT analysis and included all participants who had at least 1 Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. Here, 'Overall Number of Participants Analyzed' signifies number of participants evaluable for this outcome measure.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=7 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=3 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure in Participants With Metallo-beta-lactamase (MBL) Positive Pathogen at TOC Visit: Micro-ITT Analysis Set	28.6 Percentage of participants	66.7 Percentage of participants

SECONDARY outcome

Timeframe: At TOC visit (Day 28)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. Here, 'Overall Number of Participants Analyzed' signifies number of participants evaluable for this outcome measure.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=4 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=1 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure in Participants With MBL Positive Pathogen at TOC Visit: ME Analysis Set	50.0 Percentage of participants	0 Percentage of participants

SECONDARY outcome

Timeframe: At TOC visit day (28)

Population: Micro-ITT analysis set was a subset of the ITT analysis sets and included all participants who had at least 1 Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. Participants with a per participant response of indeterminate were excluded from this analysis. Here, 'Overall Number of Participants Analyzed' signifies number of participants evaluable for this outcome measure.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=169 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=92 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Participant Microbiological Response at TOC Visit: Micro- ITT Analysis Set	75.7 Percentage of participants	73.9 Percentage of participants

SECONDARY outcome

Timeframe: At TOC Visit (Day 28)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Participant Microbiological Response at TOC Visit: ME Analysis Set	77.2 Percentage of participants	75.9 Percentage of participants

SECONDARY outcome

Timeframe: From randomization up to 28 days

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug.

Percentage of participants who died on or before 28 days after randomization is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants Who Died on or Before 28 Days After Randomization: ITT Analysis Set	4.3 Percentage of participants	7.1 Percentage of participants

SECONDARY outcome

Timeframe: From randomization up to 28 days

Population: Micro-ITT analysis set was a subset of the ITT analysis set and included all participants who had at least 1 Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment.

Percentage of participants who died on or before 28 days after randomization is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants Who Died on or Before 28 Days After Randomization: Micro-ITT Analysis Set	2.8 Percenatge of participants	6.4 Percenatge of participants

SECONDARY outcome

Timeframe: Anytime between 25 to 30 minutes, 3.25 to 3.5 hours, 5.5 to 6.5 hours, 7.5 to 8.5 hours post start of infusion on Day 1; 2.75 to 3 hours, 3.5 to 4.5 hours, 5 to 6 and 7 to 8 hours post start of infusion on Day 4

Population: PK analysis set included all participants who had at least 1 plasma concentration data assessment available for ATM or AVI. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Plasma concentration for aztreonam according to renal function (augmented, normal and mild, moderate and severe is presented in this outcome measure. Augmented = Creatinine clearance (CrCL) \> 150 milliliters per minute (mL/min); Normal \& Mild = CrCL \> 50 to \<=150 mL/min; Moderate = CrCL \> 30 to ≤ 50 mL/min; Severe = CrCL \> 15 to ≤ 30 mL/min.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=253 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Plasma Concentration of Aztreonam Renal Function: Moderate: 2.75 to 3 hours post start of infusion on Day 4	73.33 Milligram/Liter Geometric Coefficient of Variation 183.2	—
Plasma Concentration of Aztreonam Renal Function: Augmented:25 to 30 minutes post start of infusion on Day 1	43.3 Milligram/Liter Geometric Coefficient of Variation 339.08	—
Plasma Concentration of Aztreonam Renal Function: Augmented:3.25 to 3.5 hours post start of infusion on Day 1	55.99 Milligram/Liter Geometric Coefficient of Variation 287.36	—
Plasma Concentration of Aztreonam Renal Function: Augmented: 5.5 hours to 6.5 hours post loading infusion on Day 1	26.11 Milligram/Liter Geometric Coefficient of Variation 338.5	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild: 25 to 30 min post start of infusion on Day 1	33.85 Milligram/Liter Geometric Coefficient of Variation 234.46	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild:3.25 to 3.5 hours post start of infusion on Day 1	56.24 Milligram/Liter Geometric Coefficient of Variation 222.32	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild:5.5 hours to 6.5 hours post start of infusion on Day 1	25.03 Milligram/Liter Geometric Coefficient of Variation 115.83	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild:7.5 to 8.5 hours post start of infusion on Day 1	34.62 Milligram/Liter Geometric Coefficient of Variation 54.42	—
Plasma Concentration of Aztreonam Renal Function: Moderate: 25 to 30 min post start of infusion on Day 1	54.49 Milligram/Liter Geometric Coefficient of Variation 313.99	—
Plasma Concentration of Aztreonam Renal Function: Moderate: 3.25 to 3.5 hours post start of infusion on Day 1	73.72 Milligram/Liter Geometric Coefficient of Variation 259.64	—
Plasma Concentration of Aztreonam Renal Function: Moderate: 5.5 hours to 6.5 hours post start of infusion on Day 1	52.45 Milligram/Liter Geometric Coefficient of Variation 139.9	—
Plasma Concentration of Aztreonam Renal Function: Moderate: 7.5 to 8.5 hours post start of infusion on Day 1	34 Milligram/Liter Geometric Coefficient of Variation NA Geometric coefficient of variation could not be estimated as only 1 participant was analyzed.	—
Plasma Concentration of Aztreonam Renal Function: Severe: 25 to 30 min post start of infusion on Day 1	48.98 Milligram/Liter Geometric Coefficient of Variation 187.86	—
Plasma Concentration of Aztreonam Renal Function: Severe: 3.25 to 3.5 hours post start of infusion on Day 1	50.31 Milligram/Liter Geometric Coefficient of Variation 30.13	—
Plasma Concentration of Aztreonam Renal Function: Severe: 5.5 hours to 6.5 hours post start of infusion on Day 1	48.54 Milligram/Liter Geometric Coefficient of Variation 46.87	—
Plasma Concentration of Aztreonam Renal Function: Severe: 7.5 to 8.5 hours post start of infusion on Day 1	29.42 Milligram/Liter Geometric Coefficient of Variation 34.88	—
Plasma Concentration of Aztreonam Renal Function: Augmented: 2.75 to 3 hours post start of infusion on Day 4	46.11 Milligram/Liter Geometric Coefficient of Variation 234.31	—
Plasma Concentration of Aztreonam Renal Function: Augmented: 3.5 to 4.5 hours post start of infusion on Day 4	33.56 Milligram/Liter Geometric Coefficient of Variation 204.99	—
Plasma Concentration of Aztreonam Renal Function: Augmented: 5 to 6 hours post start of infusion on Day 4	19.56 Milligram/Liter Geometric Coefficient of Variation 205.84	—
Plasma Concentration of Aztreonam Renal Function: Augmented: 7 to 8 hours post start of infusion on Day 4	14.1 Milligram/Liter Geometric Coefficient of Variation NA Geometric coefficient of variation could not be estimated as only 1 participant was analyzed.	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild: 2.75 to 3 hours post start of infusion on Day 4	56.59 Milligram/Liter Geometric Coefficient of Variation 404.54	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild: 3.5 to 4.5 hours post start of infusion on Day 4	35.69 Milligram/Liter Geometric Coefficient of Variation 422.52	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild: 5 to 6 hours post start of infusion on Day 4	21.75 Milligram/Liter Geometric Coefficient of Variation 271.62	—
Plasma Concentration of Aztreonam Renal Function: Normal & Mild: 7 to 8 hours post start of infusion on Day 4	42.98 Milligram/Liter Geometric Coefficient of Variation 62.54	—
Plasma Concentration of Aztreonam Renal Function: Moderate: 3.5 to 4.5 hours post start of infusion on Day 4	58 Milligram/Liter Geometric Coefficient of Variation 129.36	—
Plasma Concentration of Aztreonam Renal Function: Moderate: 5 to 6 hours post start of infusion on Day 4	44.72 Milligram/Liter Geometric Coefficient of Variation 59.15	—
Plasma Concentration of Aztreonam Renal Function: Moderate: 7 to 8 hours post start of infusion on Day 4	19.8 Milligram/Liter Geometric Coefficient of Variation NA Geometric coefficient of variation could not be estimated as only 1 participant was analyzed.	—
Plasma Concentration of Aztreonam Renal Function: Severe: 2.75 to 3 hours post start of infusion on Day 4	54.91 Milligram/Liter Geometric Coefficient of Variation 45.17	—
Plasma Concentration of Aztreonam Renal Function: Severe: 3.5 to 4.5 hours post start of infusion on Day 4	45.17 Milligram/Liter Geometric Coefficient of Variation 34.89	—
Plasma Concentration of Aztreonam Renal Function: Severe: 5 to 6 hours post start of infusion on Day 4	45.11 Milligram/Liter Geometric Coefficient of Variation 57.13	—
Plasma Concentration of Aztreonam Renal Function: Severe:7 to 8 hours post start of infusion on Day 4	32.69 Milligram/Liter Geometric Coefficient of Variation 55.56	—

SECONDARY outcome

Timeframe: Anytime between 25 to 30 minutes, 3.25 to 3.5 hours, 5.5 to 6.5 hours, 7.5 to 8.5 hours post start of infusion on Day 1; 2.75 to 3 hours, 3.5 to 4.5 hours, 5 to 6 and 7 to 8 hours post start of infusion on Day 4

Population: PK analysis set included all participants who had at least 1 plasma concentration data assessment available for ATM or AVI. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Plasma concentration for avibactam according to renal function (augmented, normal and mild, moderate and severe is presented in this outcome measure. Augmented = CrCL \> 150 mL/min; Normal \& Mild = CrCL \> 50 to \<=150 mL/min; Moderate = CrCL \> 30 to ≤ 50 mL/min; Severe = CrCL \> 15 to ≤ 30 mL/min.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=235 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Plasma Concentration of Avibactam Renal Function: Augmented:25 to 30 minutes post start of infusion on Day 1	10.77 Milligram/Liter Geometric Coefficient of Variation 353.86	—
Plasma Concentration of Avibactam Renal Function: Augmented:3.25 to 3.5 hours post start of infusion on Day 1	12.6 Milligram/Liter Geometric Coefficient of Variation 299.27	—
Plasma Concentration of Avibactam Renal Function: Augmented: 5.5 hours to 6.5 hours post start of infusion on Day 1	4.75 Milligram/Liter Geometric Coefficient of Variation 366.33	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild: 25 to 30 min post start of infusion on Day 1	8.81 Milligram/Liter Geometric Coefficient of Variation 338.73	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild:3.25 to 3.5 hours post start of infusion on Day 1	13.76 Milligram/Liter Geometric Coefficient of Variation 242.67	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild:5.5 hours to 6.5 hours post start of infusion on Day 1	4.85 Milligram/Liter Geometric Coefficient of Variation 209.49	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild:7.5 to 8.5 hours post start of infusion on Day 1	7.18 Milligram/Liter Geometric Coefficient of Variation 62.62	—
Plasma Concentration of Avibactam Renal Function: Moderate: 25 to 30 min post start of infusion on Day 1	13.56 Milligram/Liter Geometric Coefficient of Variation 383.79	—
Plasma Concentration of Avibactam Renal Function: Moderate: 3.25 to 3.5 hours post start of infusion on Day 1	20.28 Milligram/Liter Geometric Coefficient of Variation 262.6	—
Plasma Concentration of Avibactam Renal Function: Moderate: 5.5 hours to 6.5 hours post start of infusion on Day 1	13.47 Milligram/Liter Geometric Coefficient of Variation 160.75	—
Plasma Concentration of Avibactam Renal Function: Moderate: 7.5 to 8.5 hours post start of infusion on Day 1	7.91 Milligram/Liter Geometric Coefficient of Variation NA Geometric coefficient of variation could not be estimated as only 1 participant was analyzed.	—
Plasma Concentration of Avibactam Renal Function: Severe: 25 to 30 min post start of infusion on Day 1	14.11 Milligram/Liter Geometric Coefficient of Variation 202.08	—
Plasma Concentration of Avibactam Renal Function: Severe: 3.25 to 3.5 hours post start of infusion on Day 1	13.62 Milligram/Liter Geometric Coefficient of Variation 39.68	—
Plasma Concentration of Avibactam Renal Function: Severe: 5.5 hours to 6.5 hours post start of infusion on Day 1	11.6 Milligram/Liter Geometric Coefficient of Variation 54.34	—
Plasma Concentration of Avibactam Renal Function: Severe: 7.5 to 8.5 hours post start of infusion on Day 1	8 Milligram/Liter Geometric Coefficient of Variation 57.91	—
Plasma Concentration of Avibactam Renal Function: Augmented: 2.75 to 3 hours post start of infusion on Day 4	9.75 Milligram/Liter Geometric Coefficient of Variation 289.96	—
Plasma Concentration of Avibactam Renal Function: Augmented: 3.5 to 4.5 hours post start of infusion on Day 4	6.23 Milligram/Liter Geometric Coefficient of Variation 263.94	—
Plasma Concentration of Avibactam Renal Function: Augmented: 5 to 6 hours post start of infusion on Day 4	3.19 Milligram/Liter Geometric Coefficient of Variation 265.65	—
Plasma Concentration of Avibactam Renal Function: Augmented: 7 to 8 hours post start of infusion on Day 4	2.72 Milligram/Liter Geometric Coefficient of Variation NA Geometric coefficient of variation could not be estimated as only 1 participant was analyzed.	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild: 2.75 to 3 hours post start of infusion on Day 4	11.46 Milligram/Liter Geometric Coefficient of Variation 504.77	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild: 3.5 to 4.5 hours post start of infusion on Day 4	6.29 Milligram/Liter Geometric Coefficient of Variation 493.48	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild: 5 to 6 hours post start of infusion on Day 4	3.48 Milligram/Liter Geometric Coefficient of Variation 382.3	—
Plasma Concentration of Avibactam Renal Function: Normal & Mild: 7 to 8 hours post start of infusion on Day 4	6.19 Milligram/Liter Geometric Coefficient of Variation 51.22	—
Plasma Concentration of Avibactam Renal Function: Moderate: 2.75 to 3 hours post start of infusion on Day 4	16.98 Milligram/Liter Geometric Coefficient of Variation 208.63	—
Plasma Concentration of Avibactam Renal Function: Moderate: 3.5 to 4.5 hours post start of infusion on Day 4	12.86 Milligram/Liter Geometric Coefficient of Variation 156.96	—
Plasma Concentration of Avibactam Renal Function: Moderate: 5 to 6 hours post start of infusion on Day 4	9.23 Milligram/Liter Geometric Coefficient of Variation 72.89	—
Plasma Concentration of Avibactam Renal Function: Moderate: 7 to 8 hours post start of infusion on Day 4	4.35 Milligram/Liter Geometric Coefficient of Variation NA Geometric coefficient of variation could not be estimated as only 1 participant was analyzed.	—
Plasma Concentration of Avibactam Renal Function: Severe: 2.75 to 3 hours post start of infusion on Day 4	14.35 Milligram/Liter Geometric Coefficient of Variation 44.72	—
Plasma Concentration of Avibactam Renal Function: Severe: 3.5 to 4.5 hours post start of infusion on Day 4	11.68 Milligram/Liter Geometric Coefficient of Variation 42.15	—
Plasma Concentration of Avibactam Renal Function: Severe: 5 to 6 hours post start of infusion on Day 4	9.99 Milligram/Liter Geometric Coefficient of Variation 67.87	—
Plasma Concentration of Avibactam Renal Function: Severe: Moderate: 7 to 8 hours post start of infusion on Day 4	8.97 Milligram/Liter Geometric Coefficient of Variation 47.28	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Population PK predicted maximum plasma concentration for a dosing interval at steady-state (Cmax,ss) for participants who received aztreonam-avibactam in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Clinical response categories included, clinical cure=improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Failure was defined as participants who met any of the following criteria like death (after receiving at least 48 hours of study treatment) and participants who received treatment with further antibiotics for the index infection. Indeterminate was defined as death (after receiving less than 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=262 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Clinical cure	52.47 Milligram per liter (mg/L) Geometric Coefficient of Variation 37.49	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Failure	56.71 Milligram per liter (mg/L) Geometric Coefficient of Variation 62.52	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Indeterminate	66.21 Milligram per liter (mg/L) Geometric Coefficient of Variation 12.7	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam HAP:Clinical cure	85.24 Milligram per liter (mg/L) Geometric Coefficient of Variation 48.49	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam HAP: Failure	64.57 Milligram per liter (mg/L) Geometric Coefficient of Variation 33.97	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam HAP: Indeterminate	61.79 Milligram per liter (mg/L) Geometric Coefficient of Variation 27.2	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Clinical Cure	54.89 Milligram per liter (mg/L) Geometric Coefficient of Variation 30.42	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Failure	56.5 Milligram per liter (mg/L) Geometric Coefficient of Variation 31.1	—
Maximum Plasma Concentration for a Dosing Interval at Steady-State (Cmax, ss) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Indeterminate	85.34 Milligram per liter (mg/L) Geometric Coefficient of Variation NA Standard deviation (SD) was not estimated because of less number of participants in this event.	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Population PK predicted (%fT\>MIC ATM of 8 mg/L) for participants who received aztreonam-avibactam in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Clinical response categories included, clinical cure=improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Failure was defined as participants who met any of the following criteria like death (after receiving at least 48 hours of study treatment) and participants who received treatment with further antibiotics for the index infection. Indeterminate was defined as death (after receiving less than 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=262 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Clinical cure	90.4 Percentage of time Geometric Coefficient of Variation 41.9	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Failure	73.81 Percentage of time Geometric Coefficient of Variation 134.39	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Indeterminate	100 Percentage of time Geometric Coefficient of Variation 0	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam HAP:Clinical cure	97.87 Percentage of time Geometric Coefficient of Variation 7.67	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam HAP: Failure	97.2 Percentage of time Geometric Coefficient of Variation 8.4	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam HAP: Indeterminate	100 Percentage of time Geometric Coefficient of Variation 0	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Clinical Cure	95.29 Percentage of time Geometric Coefficient of Variation 8.94	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Failure	96.38 Percentage of time Geometric Coefficient of Variation 10.02	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Indeterminate	100 Percentage of time Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: 0 to 24 hours at TOC (Day 28)

Population: Analysis population included participants from PK and ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Population PK predicted (AUC24,ss) for participants who received aztreonam-avibactam in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Clinical response categories included, clinical cure=improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Failure was defined as participants who met any of the following criteria like death (after receiving at least 48 hours of study treatment) and participants who received treatment with further antibiotics for the index infection. Indeterminate was defined as death (after receiving less than 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=262 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Clinical cure	816.18 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 41.83	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Failure	877.5 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 85.91	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam cIAI: Indeterminate	1069.1 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 15.82	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam HAP:Clinical cure	1420.1 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 54.62	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam HAP: Failure	1079.4 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 34.1	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam HAP: Indeterminate	1056.8 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 35.68	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Clinical cure	858.39 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 32.49	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Failure	912.23 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation 38.1	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss ) According to Clinical Response by Infection Type at TOC: Aztreonam VAP: Indeterminate	1084.6 Milligramhours per liter (mgh/L) Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and micro-ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Number Analyzed=participants evaluable for the specified rows.

Population PK predicted (Cmax,ss) for participants who received ATM-AVI in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Microbiological response included Favorable =baseline pathogens for participant had a favorable outcome. Eradication: Absence of causative pathogen from an appropriately obtained specimen at site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Unfavorable=persistence, persistence with increasing MIC, or presumed persistence. Persistence= Causative organism still present from appropriately obtained specimen at site of infection. Presumed persistence= Participant assessed as a clinical failure and repeat culture of specimens were not performed/clinically indicated. Indeterminate = death (after receiving \< 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=174 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Favorable	53.26 Milligram per liter (mg/L) Geometric Coefficient of Variation 34.03	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Unfavorable	53.71 Milligram per liter (mg/L) Geometric Coefficient of Variation 67.14	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Indeterminate	62.97 Milligram per liter (mg/L) Geometric Coefficient of Variation 9.49	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP:Favorable	86.9 Milligram per liter (mg/L) Geometric Coefficient of Variation 71.56	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP: Unfavorable	55.48 Milligram per liter (mg/L) Geometric Coefficient of Variation 38.83	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP: Indeterminate	66.2 Milligram per liter (mg/L) Geometric Coefficient of Variation 33.87	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Favorable	50.71 Milligram per liter (mg/L) Geometric Coefficient of Variation 37.56	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Unfavorable	59.77 Milligram per liter (mg/L) Geometric Coefficient of Variation 31.52	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Indeterminate	85.34 Milligram per liter (mg/L) Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: 0 to 24 hours at TOC (Day 28)

Population: Analysis population included participants from PK and micro-ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' =participants evaluable for the specified rows.

Population PK predicted (AUC24,ss) for participants who received ATM-AVI in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Microbiological response included Favorable =baseline pathogens for participant had a favorable outcome. Eradication: Absence of causative pathogen from an appropriately obtained specimen at site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Unfavorable=persistence, persistence with increasing MIC, or presumed persistence. Persistence= Causative organism still present from appropriately obtained specimen at site of infection. Presumed persistence= Participant assessed as a clinical failure and repeat culture of specimens were not performed/clinically indicated. Indeterminate = death (after receiving \< 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=174 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Favorable	830.23 Milligram*hours per liter Geometric Coefficient of Variation 38.42	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Unfavorable	826.63 Milligram*hours per liter Geometric Coefficient of Variation 95.22	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Indeterminate	1010.2 Milligram*hours per liter Geometric Coefficient of Variation 9.17	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP:Favorable	1446.1 Milligram*hours per liter Geometric Coefficient of Variation 82.6	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP: Unfavorable	909.59 Milligram*hours per liter Geometric Coefficient of Variation 45.06	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP: Indeterminate	1237.9 Milligram*hours per liter Geometric Coefficient of Variation 38.16	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Favorable	760.26 Milligram*hours per liter Geometric Coefficient of Variation 40.54	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Unfavorable	974.21 Milligram*hours per liter Geometric Coefficient of Variation 37.82	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Indeterminate	1084.6 Milligram*hours per liter Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and micro-ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' =participants evaluable for the specified rows.

Population PK predicted (%fT\>MIC ATM of 8 mg/L) for participants who received ATM-AVI in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Microbiological response included Favorable =baseline pathogens for participant had a favorable outcome. Eradication: Absence of causative pathogen from an appropriately obtained specimen at site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Unfavorable=persistence, persistence with increasing MIC, or presumed persistence. Persistence= Causative organism still present from appropriately obtained specimen at site of infection. Presumed persistence= Participant assessed as a clinical failure and repeat culture of specimens were not performed/clinically indicated. Indeterminate = death (after receiving \< 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=174 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Favorable	92.57 Percentage of time Geometric Coefficient of Variation 17.66	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Unfavorable	68.02 Percentage of time Geometric Coefficient of Variation 171.87	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam cIAI: Indeterminate	100 Percentage of time Geometric Coefficient of Variation 0	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP:Favorable	95.53 Percentage of time Geometric Coefficient of Variation 11.05	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP: Unfavorable	93.9 Percentage of time Geometric Coefficient of Variation 14.14	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam HAP: Indeterminate	100 Percentage of time Geometric Coefficient of Variation 0	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Favorable	90.8 Percentage of time Geometric Coefficient of Variation 12.3	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Unfavorable	97.42 Percentage of time Geometric Coefficient of Variation 9.54	—
Percentage of Time That Free Plasma Concentrations Are Above the Minimum Inhibitory Concentration Over a Dosing Interval (%fT>MIC Aztreonam (ATM) of 8 mg/L) According to Microbiological Response by Infection Type at TOC: Aztreonam VAP: Indeterminate	100 Percentage of time Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: 0 to 24 hours at TOC (Day 28)

Population: Analysis population included participants from PK and ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Population PK predicted (AUC24,ss) for participants who received aztreonam-avibactam in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Clinical response categories included, clinical cure=improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Failure was defined as participants who met any of the following criteria like death (after receiving at least 48 hours of study treatment) and participants who received treatment with further antibiotics for the index infection. Indeterminate was defined as death (after receiving less than 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=262 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Clinical cure	164.92 Milligram*hour per liter Geometric Coefficient of Variation 45.91	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Failure	187.41 Milligram*hour per liter Geometric Coefficient of Variation 96.93	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Indeterminate	213.92 Milligram*hour per liter Geometric Coefficient of Variation 20.81	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam HAP:Clinical cure	291.47 Milligram*hour per liter Geometric Coefficient of Variation 61.75	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam HAP: Failure	214.99 Milligram*hour per liter Geometric Coefficient of Variation 36.09	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam HAP: Indeterminate	257.37 Milligram*hour per liter Geometric Coefficient of Variation 71.75	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Clinical cure	176.95 Milligram*hour per liter Geometric Coefficient of Variation 31.43	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Failure	178.68 Milligram*hour per liter Geometric Coefficient of Variation 38.99	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Indeterminate	218.09 Milligram*hour per liter Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Population PK predicted (Cmax,ss) for participants who received aztreonam-avibactam in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Clinical response categories included, clinical cure=improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Failure was defined as participants who met any of the following criteria like death (after receiving at least 48 hours of study treatment) and participants who received treatment with further antibiotics for the index infection. Indeterminate was defined as death (after receiving less than 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=262 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Clinical cure	11.01 Milligram per liter (mg/L) Geometric Coefficient of Variation 42.14	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Failure	12.48 Milligram per liter (mg/L) Geometric Coefficient of Variation 72.59	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Indeterminate	14.04 Milligram per liter (mg/L) Geometric Coefficient of Variation 16.52	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam HAP:Clinical cure	18.41 Milligram per liter (mg/L) Geometric Coefficient of Variation 55.07	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam HAP: Failure	13.46 Milligram per liter (mg/L) Geometric Coefficient of Variation 33.52	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam HAP: Indeterminate	15.24 Milligram per liter (mg/L) Geometric Coefficient of Variation 49.1	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Clinical Cure	11.64 Milligram per liter (mg/L) Geometric Coefficient of Variation 31.01	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Failure	11.44 Milligram per liter (mg/L) Geometric Coefficient of Variation 32.65	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss ) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Indeterminate	18.93 Milligram per liter (mg/L) Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies participants evaluable for the specified rows.

Population PK predicted (%fT\>CT of 2.5mg/L) for participants who received aztreonam-avibactam in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Clinical response categories included, clinical cure=improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Failure was defined as participants who met any of the following criteria like death (after receiving at least 48 hours of study treatment) and participants who received treatment with further antibiotics for the index infection. Indeterminate was defined as death (after receiving less than 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=262 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Clinical cure	85.53 Percentage of time Geometric Coefficient of Variation 43.26	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Failure	71.92 Percentage of time Geometric Coefficient of Variation 133.68	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam cIAI: Indeterminate	98.52 Percentage of time Geometric Coefficient of Variation 2.81	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam HAP:Clinical cure	95.99 Percentage of time Geometric Coefficient of Variation 11.57	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam HAP: Failure	95.28 Percentage of time Geometric Coefficient of Variation 12.12	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam HAP: Indeterminate	92.75 Percentage of time Geometric Coefficient of Variation 11.19	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Clinical Cure	92 Percentage of time Geometric Coefficient of Variation 13.01	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Failure	94.08 Percentage of time Geometric Coefficient of Variation 12.93	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval (%fT>CT of 2.5mg/L) According to Clinical Response by Infection Type at TOC: Avibactam VAP: Indeterminate	100 Percentage of time Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: 0 to 24 hours At TOC (Day 28)

Population: Analysis population included participants from PK and micro-ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' =participants evaluable for the specified rows.

Population PK predicted (AUC24,ss) for participants who received ATM-AVI in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Microbiological response included Favorable =baseline pathogens for participant had a favorable outcome. Eradication: Absence of causative pathogen from an appropriately obtained specimen at site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Unfavorable=persistence, persistence with increasing MIC, or presumed persistence. Persistence= Causative organism still present from appropriately obtained specimen at site of infection. Presumed persistence= Participant assessed as a clinical failure and repeat culture of specimens were not performed/clinically indicated. Indeterminate = death (after receiving\<48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=174 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Favorable	166.4 Milligram*hours per liter Geometric Coefficient of Variation 40.88	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Unfavorable	177.65 Milligram*hours per liter Geometric Coefficient of Variation 106.25	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Indeterminate	197.01 Milligram*hours per liter Geometric Coefficient of Variation 7.31	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam HAP:Favorable	293.49 Milligram*hours per liter Geometric Coefficient of Variation 95.13	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam HAP: Unfavorable	196.38 Milligram*hours per liter Geometric Coefficient of Variation 61.95	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam HAP: Indeterminate	359.31 Milligram*hours per liter Geometric Coefficient of Variation 71.12	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Favorable	157.79 Milligram*hours per liter Geometric Coefficient of Variation 43.71	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Unfavorable	192.85 Milligram*hours per liter Geometric Coefficient of Variation 38.42	—
Area Under the Plasma Concentration-time Curve Over 24 Hours at Steady-state (AUC24,ss) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Indeterminate	218.09 Milligram*hours per liter Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and micro-ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' =participants evaluable for the specified rows.

Population PK predicted (Cmax,ss (mg/L)) for participants who received ATM-AVI in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Microbiological response included Favorable =baseline pathogens for participant had a favorable outcome. Eradication: Absence of causative pathogen from an appropriately obtained specimen at site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Unfavorable=persistence, persistence with increasing MIC, or presumed persistence. Persistence= Causative organism still present from appropriately obtained specimen at site of infection. Presumed persistence= Participant assessed as a clinical failure and repeat culture of specimens were not performed/clinically indicated. Indeterminate = death (after receiving\<48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=174 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Favorable	11.1 Milligram per liter (mg/L) Geometric Coefficient of Variation 37.2	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Unfavorable	11.83 Milligram per liter (mg/L) Geometric Coefficient of Variation 76.48	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Indeterminate	13.03 Milligram per liter (mg/L) Geometric Coefficient of Variation 8.01	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam HAP:Favorable	18.55 Milligram per liter (mg/L) Geometric Coefficient of Variation 84.68	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam HAP: Unfavorable	12.31 Milligram per liter (mg/L) Geometric Coefficient of Variation 51.34	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam HAP: Indeterminate	18.72 Milligram per liter (mg/L) Geometric Coefficient of Variation 55.03	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Favorable	10.75 Milligram per liter (mg/L) Geometric Coefficient of Variation 42.72	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Unfavorable	12.28 Milligram per liter (mg/L) Geometric Coefficient of Variation 32.85	—
Maximum Plasma Concentration for a Dosing Interval at Steady-state (Cmax,ss (mg/L)) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Indeterminate	18.93 Milligram per liter (mg/L) Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: At TOC (Day 28)

Population: Analysis population included participants from PK and micro-ITT analysis set. All participants reported under 'Overall Number of Participants Analyzed' included participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' =participants evaluable for the specified rows.

Population PK predicted (%fT\>CT of 2.5 mg/L) for participants who received ATM-AVI in studies C3601002 (NCT03329092) and C3601009 (NCT03580044). Microbiological response included Favorable =baseline pathogens for participant had a favorable outcome. Eradication: Absence of causative pathogen from an appropriately obtained specimen at site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Unfavorable=persistence, persistence with increasing MIC, or presumed persistence. Persistence= Causative organism still present from appropriately obtained specimen at site of infection. Presumed persistence= Participant assessed as a clinical failure and repeat culture of specimens were not performed/clinically indicated. Indeterminate = death (after receiving \< 48 hours of study treatment) and for cIAI participants inadequate infection source control at time of initial surgical procedure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=174 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Favorable	87.93 Percentage of time Geometric Coefficient of Variation 21.78	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Unfavorable	66.43 Percentage of time Geometric Coefficient of Variation 170.59	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam cIAI: Indeterminate	99.24 Percentage of time Geometric Coefficient of Variation 1.52	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam HAP:Favorable	92.26 Percentage of time Geometric Coefficient of Variation 16.44	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam HAP: Unfavorable	90.03 Percentage of time Geometric Coefficient of Variation 18.83	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam HAP: Indeterminate	100 Percentage of time Geometric Coefficient of Variation 0	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Favorable	87.47 Percentage of time Geometric Coefficient of Variation 16.8	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Unfavorable	95.52 Percentage of time Geometric Coefficient of Variation 11.79	—
Percent of Time That Free Plasma Concentrations Are Above the Threshold Concentration Over a Dosing Interval; (%fT>CT of 2.5 mg/L) According to Microbiological Response by Infection Type at TOC: Avibactam VAP: Indeterminate	100 Percentage of time Geometric Coefficient of Variation NA SD was not estimated because of less number of participants in this events.	—

SECONDARY outcome

Timeframe: From start of study treatment until end of late follow-up (Up to Day 45)

Population: Safety analysis set included all participants who received any amount of study treatment. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

An adverse event (AE) was any untoward medical occurrence in a study participant administered medicinal product,; the event need not necessarily have a causal relationship with product treatment or usage. A serious adverse event (SAE) was any untoward medical occurrence at any dose that: resulted in death; was life-threatening; required inpatient hospitalization or prolongation of hospitalization; resulted in persistent or significant disability/incapacity (substantial disruption of the ability to conduct normal life functions); resulted in congenital abnormal/birth defect or considered an important medical event.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=275 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=137 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Adverse Events (AEs) and Serious AEs AEs	177 Participants	87 Participants
Number of Participants With Adverse Events (AEs) and Serious AEs SAEs	53 Participants	25 Participants

SECONDARY outcome

Timeframe: From start of study treatment until TOC visit (Up to Day 28)

Population: Safety analysis set included all participants who received any amount of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants available for specified rows.

Criteria for potential clinically significant hematology results were as follows: hemoglobin, hematocrit and erythrocyte \<0.7\*lower limit of normal \[LLN\] and \>30% decrease from Baseline (DFB); \>1.3\*upper limit of normal (ULN) and \>30% increase from Baseline (IFB). Platelet count \<0.65\*LLN and \> 50% decrease from baseline; \> 1.5 \* ULN and \> 100% increase from baseline. leukocyte: \< 0.65\* LLN and \> 60% decrease from baseline; \> 1.5\* ULN and 100% increase from baseline. Neutrophils/leukocytes \< 0.65 \* LLN and \>75% decrease from baseline; \> 1.6\*ULN and \> 100% increase from baseline. Lymphocytes/leukocytes \< 0.25\* LLN and \> 75% decrease from baseline;\> 1.5\* ULN and \> 100% increase from baseline, Eosinophils/leukocytes, Monocytes/leukocytes, Basophils/leukocytes \> 4.0\* ULN and \> 300% increase from baseline.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=275 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=137 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Hematocrit < 0.7*LLN and > 30% Decrease from Baseline	6 Participants	3 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Hematocrit > 1.3* ULN and > 30% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Hemoglobin< 0.7* LLN and > 30% Decrease from Baseline	8 Participants	3 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Hemoglobin > 1.3* ULN and > 30% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Erythrocytes < 0.7* LLN and > 30% Decrease from Baseline	7 Participants	3 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Erythrocytes > 1.3* ULN and > 30% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Leukocytes < 0.65* LLN and > 60% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Leukocytes > 1.5* ULN and > 100% Increase from Baseline	12 Participants	5 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Neutrophils/Leukocytes < 0.65* LLN and > 75% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Neutrophils/Leukocytes > 1.6* ULN and > 100% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Monocytes/Leukocytes > 4.0* ULN and > 300% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Lymphocytes/Leukocytes < 0.25* LLN and > 75% Decrease from Baseline	1 Participants	1 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Lymphocytes/Leukocytes > 1.5* ULN and > 100% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Eosinophils/Leukocytes > 4.0* ULN and > 300% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Basophils/Leukocytes > 4.0* ULN and > 300% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Platelets < 0.65* LLN and > 50% Decrease from Baseline	3 Participants	2 Participants
Number of Participants With Potentially Clinically Significant Hematology Abnormalities Platelets > 1.5* ULN and > 100% Increase from Baseline	12 Participants	7 Participants

SECONDARY outcome

Timeframe: From start of study treatment until At TOC visit (Up to Day 28)

Population: Safety analysis set included all participants who received any amount of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants available for specified rows.

Albumin \< 0.5\* LLN and\> 50% decrease from baseline (DFB);\> 1.5 \* ULN and\> 50% increase from baseline (IFB). Alkaline phosphatase \< 0.5 \* LLN and\> 80% DFB;\> 3.0 \* ULN and\> 100%. Alanine and Aspartate aminotransferase \> 3.0 \* ULN and\> 100% IFB. Bicarbonate \< 0.7 \* LLN and \> 40% DFB;\> 1.3 \* ULN and\> 40% IFB. Blood urea nitrogen \< 0.2 \* LLN and \> 100% DFB; \> 3.0 \* ULN and \> 200% IFB. Calcium \< 0.7 \* LLN and \> 30% DFB;\> 1.3 \* ULN and\> 30% IFB. Chloride \< 0.8 \* LLN \>and 20% DFB; \> 1.2 \* ULN and \> 20% IFB. Creatinine \> 2.0 \* ULN and\> 100% IFB; Glucose \< 0.6 \* LLN and\> 40% DFB; \> 3.0 \* ULN and\> 200% IFB. Potassium \< 0.8 \* LLN and \> 20% DFB; \> 1.2 \* ULN and\> 20% IFB. Sodium \< 0.85 \* LLN and\> 10% DFB;\> 1.1 \* ULN and \>10% IFB. Bilirubin \> 1.5 \* ULN and \> 100% IFB.; Direct bilirubin \> 2.0 \* ULN and \> 150% IFB.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=275 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=137 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Aspartate Aminotransferase >3.0* ULN and > 100% Increase from Baseline	25 Participants	14 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Alanine Aminotransferase > 3.0* ULN and > 100% Increase from Baseline	24 Participants	10 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Alkaline Phosphatase < 0.5* LLN and > 80% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Alkaline Phosphatase > 3.0* ULN and > 100% Increase from Baseline	5 Participants	4 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Bilirubin > 1.5* ULN and > 100% Increase from Baseline	2 Participants	3 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Direct Bilirubin > 2.0* ULN and > 150% Increase from Baseline	2 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Creatinine > 2.0* ULN and > 100% Increase from Baseline	0 Participants	3 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Sodium < 0.85* LLN and > 10% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Sodium> 1.1* ULN and > 10% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Potassium < 0.8* LLN and > 20% Decrease from Baseline	6 Participants	1 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Potassium > 1.2* ULN and > 20% Increase from Baseline	5 Participants	4 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Chloride< 0.8* LLN and > 20% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Chloride > 1.2* ULN and > 20% Increase from Baseline	1 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Bicarbonate < 0.7* LLN and > 40% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Bicarbonate > 1.3* ULN and > 40% Increase from Baseline	3 Participants	1 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Calcium < 0.7* LLN and > 30% Decrease from Baseline	2 Participants	1 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Calcium > 1.3* ULN and > 30% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Albumin < 0.5* LLN and > 50% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Albumin > 1.5* ULN and > 50% Increase from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Glucose < 0.6* LLN and > 40% Decrease from Baseline	0 Participants	1 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Glucose > 3.0* ULN and > 200% Increase from Baseline	2 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Urea Nitrogen < 0.2* LLN and > 100% Decrease from Baseline	0 Participants	0 Participants
Number of Participants With Potentially Clinically Significant Clinical Chemistry Abnormalities Urea Nitrogen > 3.0* ULN and > 200% Increase from Baseline	0 Participants	0 Participants

SECONDARY outcome

Timeframe: From start of study treatment until TOC visit (Up to Day 28)

Population: Safety analysis set included all participants who received any amount of study treatment. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure and 'Number Analyzed' signifies participants evaluable for the specified rows.

Vitals signs, included blood pressure and, heart rate. Blood pressure (BP) and heart rate were measured using a semiautomatic BP recording device with the participant in a supine position after at least 10 minutes of rest. Criteria for abnormalities included: Systolic BP (millimeters of mercury \[mmHg\]): value more than (\>) 150 and increase from baseline more than equal (\>= 30) or value less than (\<) 90 and decrease from baseline \>= 30; DBP: value \> 100 and increase from baseline \>=20 or Value \< 50 and decrease from baseline \>= 20; Heart Rate (beats per minute \[BPM\]): value \< 40 or \> 120.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=271 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=136 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Abnormalities in Vital Signs Diastolic BP (mmHg) Value < 50 and decrease from baseline ≥ 20	10 Participants	5 Participants
Number of Participants With Abnormalities in Vital Signs Systolic BP (mmHg) Value more than (>) 150 and increase from baseline more than equal (≥ to 30)	35 Participants	16 Participants
Number of Participants With Abnormalities in Vital Signs Systolic BP (mmHg) Value less than (<) 90 and decrease from baseline more than equal (≥) 30	8 Participants	3 Participants
Number of Participants With Abnormalities in Vital Signs Diastolic BP (mmHg) Value > 100 and increase from baseline ≥ 20	8 Participants	0 Participants
Number of Participants With Abnormalities in Vital Signs Heart Rate (BPM) Value < 40 or > 120	265 Participants	135 Participants

SECONDARY outcome

Timeframe: Screening, End of treatment (up to 24 hours post infusion on Day 14) and Test of Cure (Day 28)

Population: The safety analysis set included all participants who received any amount of study treatment. Here, 'Number Analyzed' signifies number of participants available for specified rows.

A complete physical examination was performed and included an assessment of the following: general appearance including site of infection, skin, head and throat (head, eyes, ears, nose, and throat), lymph nodes, lungs, cardiovascular (CV), abdomen, musculoskeletal, and neurological systems.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=275 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=137 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Abnormal Physical Examination Finding Abdomen: Screening	184 Participants	103 Participants
Number of Participants With Abnormal Physical Examination Finding Abdomen: End of Treatment	56 Participants	30 Participants
Number of Participants With Abnormal Physical Examination Finding Abdomen: Test of Cure	31 Participants	12 Participants
Number of Participants With Abnormal Physical Examination Finding Cardiovascular: Screening	50 Participants	22 Participants
Number of Participants With Abnormal Physical Examination Finding Cardiovascular: End of Treatment	27 Participants	14 Participants
Number of Participants With Abnormal Physical Examination Finding Cardiovascular: Test of Cure	20 Participants	10 Participants
Number of Participants With Abnormal Physical Examination Finding Ears: Screening	1 Participants	1 Participants
Number of Participants With Abnormal Physical Examination Finding Ears: End of Treatment	0 Participants	1 Participants
Number of Participants With Abnormal Physical Examination Finding Ears:Test of Cure	0 Participants	1 Participants
Number of Participants With Abnormal Physical Examination Finding Eyes: Screening	13 Participants	4 Participants
Number of Participants With Abnormal Physical Examination Finding Eyes End of Treatment	7 Participants	1 Participants
Number of Participants With Abnormal Physical Examination Finding Eyes: Test of Cure	6 Participants	1 Participants
Number of Participants With Abnormal Physical Examination Finding General appearance: Screening	77 Participants	35 Participants
Number of Participants With Abnormal Physical Examination Finding General appearance: End of Treatment	34 Participants	15 Participants
Number of Participants With Abnormal Physical Examination Finding General appearance: Test of Cure	16 Participants	8 Participants
Number of Participants With Abnormal Physical Examination Finding Head: Screening	12 Participants	4 Participants
Number of Participants With Abnormal Physical Examination Finding Head: End of Treatment	10 Participants	5 Participants
Number of Participants With Abnormal Physical Examination Finding Head: Test of Cure	6 Participants	2 Participants
Number of Participants With Abnormal Physical Examination Finding Lungs: Screening	70 Participants	37 Participants
Number of Participants With Abnormal Physical Examination Finding Lungs: End of Treatment	45 Participants	15 Participants
Number of Participants With Abnormal Physical Examination Finding Lungs: Test of Cure	22 Participants	8 Participants
Number of Participants With Abnormal Physical Examination Finding Lymph nodes: Screening	1 Participants	0 Participants
Number of Participants With Abnormal Physical Examination Finding Lymph nodes: End of Treatment	1 Participants	0 Participants
Number of Participants With Abnormal Physical Examination Finding Lymph nodes: Test of Cure	0 Participants	0 Participants
Number of Participants With Abnormal Physical Examination Finding Musculoskeletal: Screening	21 Participants	10 Participants
Number of Participants With Abnormal Physical Examination Finding Musculoskeletal: End of Treatment	17 Participants	9 Participants
Number of Participants With Abnormal Physical Examination Finding Musculoskeletal: Test of Cure	9 Participants	3 Participants
Number of Participants With Abnormal Physical Examination Finding Neurological: Screening	37 Participants	13 Participants
Number of Participants With Abnormal Physical Examination Finding Neurological: End of Treatment	34 Participants	9 Participants
Number of Participants With Abnormal Physical Examination Finding Neurological: Test of Cure	17 Participants	6 Participants
Number of Participants With Abnormal Physical Examination Finding Nose: Screening	4 Participants	3 Participants
Number of Participants With Abnormal Physical Examination Finding Nose: End of Treatment	2 Participants	0 Participants
Number of Participants With Abnormal Physical Examination Finding Nose: Test of Cure	1 Participants	0 Participants
Number of Participants With Abnormal Physical Examination Finding Skin: Screening	47 Participants	25 Participants
Number of Participants With Abnormal Physical Examination Finding Skin: End of Treatment	33 Participants	22 Participants
Number of Participants With Abnormal Physical Examination Finding Skin: Test of Cure	21 Participants	12 Participants
Number of Participants With Abnormal Physical Examination Finding Throat: Screening	9 Participants	0 Participants
Number of Participants With Abnormal Physical Examination Finding Throat: End of Treatment	10 Participants	1 Participants
Number of Participants With Abnormal Physical Examination Finding Throat: Test of Cure	4 Participants	1 Participants

SECONDARY outcome

Timeframe: Baseline (latest non-missing value before start of treatment) and Day 3

Population: The safety analysis set included all participants who received any amount of study treatment.

Standard 12-lead ECGs were recorded with the participants in the supine position after the participant had rested in this position for 10 minutes. Clinically significant findings were based on investigators assessment.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=275 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=137 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Abnormal Clinically Significant Electrocardiogram (ECG) Findings Baseline	16 Participants	5 Participants
Number of Participants With Abnormal Clinically Significant Electrocardiogram (ECG) Findings Day 3	11 Participants	6 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: The ITT analysis set included all randomized participants regardless of the treatment received.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at End of Treatment (EOT) Visit: ITT Analysis Set	75.9 Percentage of participants Interval 70.6 to 80.6	73.6 Percentage of participants Interval 65.8 to 80.3

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: Micro-ITT analysis set was a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. For cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at EOT Visit: Micro-ITT Analysis Set	79.7 Percentage of participants Interval 73.3 to 85.1	80.9 Percentage of participants Interval 72.0 to 87.8

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: Analysis was performed on CE analysis set.

Clinical cure = improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method. CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=213 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=105 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at EOT Visit: CE Analysis Set	82.2 Percentage of participants Interval 76.6 to 86.8	81.9 Percentage of participants Interval 73.7 to 88.4

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who have at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure at EOT Visit: ME Analysis Set	84.6 Percentage of participants Interval 78.1 to 89.7	83.5 Percentage of participants Interval 74.2 to 90.4

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: The ITT analysis set included all randomized participants regardless of the treatment received. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure by Type of Infection at EOT Visit: ITT Analysis Set cIAI	81.7 Percentage of participants Interval 76.1 to 86.5	79.8 Percentage of participants Interval 71.3 to 86.6
Percentage of Participants With Clinical Cure by Type of Infection at EOT Visit: ITT Analysis Set HAP/VAP	59.5 Percentage of participants Interval 48.1 to 70.1	55.6 Percentage of participants Interval 39.4 to 70.8

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 24)

Population: CE analysis set. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure = improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. 95% CI was based on Jeffrey's method. CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=213 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=105 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure by Type of Infection at EOT Visit: CE Analysis Set cIAI	88.7 Percentage of participants Interval 83.2 to 92.8	85.5 Percentage of participants Interval 76.8 to 91.8
Percentage of Participants With Clinical Cure by Type of Infection at EOT Visit: CE Analysis Set HAP/VAP	57.8 Percentage of participants Interval 43.2 to 71.4	68.2 Percentage of participants Interval 47.4 to 84.5

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: Micro-ITT analysis set was a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. Percentage of participants with clinical cure by pathogen resistance type (ATM non-susceptible and Meropenem non-susceptible based on European Committee on Antimicrobial Susceptibility Testing \[EUCAST\] criteria and Clinical and Laboratory Standards Institute \[CLSI\] criteria, Extended spectrum beta-lactamases \[ESBL\]-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ESBL-positive	72.0 Percentage of participants	75.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ATM non-susceptible, EUCAST	74.5 Percentage of participants	75.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ATM non-susceptible, CLSI	68.4 Percentage of participants	74.2 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Meropenem non-susceptible, EUCAST	57.9 Percentage of participants	72.7 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Meropenem non-susceptible, CLSI	58.8 Percentage of participants	75.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Carbapenemase-positive	61.5 Percentage of participants	50.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Serene Carbapenemase	57.1 Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Metallo-beta-lactamase-positive	57.1 Percentage of participants	66.7 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC (Day 28)

Population: Micro-ITT analysis set was a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. Percentage of participants with clinical cure by pathogen resistance type (ATM non-susceptible and Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ATM non-susceptible, EUCAST	63.6 Percentage of participants	55.6 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ATM non-susceptible, CLSI	60.5 Percentage of participants	61.3 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Meropenem non-susceptible,	42.1 Percentage of participants	45.5 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Meropenem non-susceptible, CLSI	41.2 Percentage of participants	50.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ESBL-positive	68.0 Percentage of participants	70.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Carbapenemase-positive	30.8 Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Serene Carbapenemase	28.6 Percentage of participants	0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Metallo-beta-lactamase-positive	28.6 Percentage of participants	66.7 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT (Within 24 hours after last infusion on Day 14)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. Percentage of participants with clinical cure by pathogen resistance type (ATM non-susceptible and Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set ATM non-susceptible, EUCAST	81.1 Percentage of participants	78.6 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set ATM non-susceptible, CLSI	76.7 Percentage of participants	76.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set Meropenem non-susceptible, EUCAST	69.2 Percentage of participants	62.5 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set Meropenem non-susceptible, CLSI	69.2 Percentage of participants	62.5 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set ESBL-positive	77.3 Percentage of participants	82.4 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set Carbapenemase-positive	80.0 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set Serene Carbapenemase	66.7 Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at EOT Visit: ME Analysis Set Metallo-beta-lactamase-positive	100.0 Percentage of participants	0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC visit (Day 28)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Clinical cure was defined as improvement in baseline signs and symptoms such that after study treatment, no further antimicrobial treatment for the index infection (i.e., cIAI or HAP/VAP) was required. Additionally, for cIAI participants, no unplanned drainage or surgical intervention was necessary since the initial procedure. Clinical cure was determined by the Independent Clinical Adjudication Committee. Percentage of participants with clinical cure by pathogen resistance type (ATM non-susceptible and Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set ATM non-susceptible, EUCAST Criteria	70.3 Percentage of participants	60.7 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set ATM non-susceptible, CLSI Criteria	66.7 Percentage of participants	64.0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set Meropenem non-susceptible, EUCAST Criteria	46.2 Percentage of participants	37.5 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set Meropenem non-susceptible, CLSI Criteria	46.2 Percentage of participants	37.5 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set ESBL-positive	72.7 Percentage of participants	76.5 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set Carbapenemase-positive	40.0 Percentage of participants	0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set Serene Carbapenemase	33.3 Percentage of participants	0 Percentage of participants
Percentage of Participants With Clinical Cure by Pathogen Resistance Type at TOC Visit: ME Analysis Set Metallo-beta-lactamase-positive	50.0 Percentage of participants	0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: Micro-ITT analysis set is a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. Participants with a per participant response of indeterminate were excluded from this analysis. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=169 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=93 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per Participant Microbiological Response at EOT Visit: Micro-ITT Analysis Set	84.6 Percentage of participants	83.9 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT visit (Within 24 hours after last infusion on Day 14)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per Participant Microbiological Response at EOT Visit : ME Analysis Set	85.9 Percentage of participants	86.1 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT (Within 24 hours after last infusion on Day 14)

Population: Micro-ITT analysis set is a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Only those pathogens are reported which had more than or equal to 10 isolates for either treatment group.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: Micro-ITT Analysis Set Escherichia coli	95 Participants	48 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: Micro-ITT Analysis Set Klebsiella pneumoniae	19 Participants	18 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: Micro-ITT Analysis Set Pseudomonas aeruginosa	14 Participants	5 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: Micro-ITT Analysis Set Streptococcus anginosus group	13 Participants	4 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: Micro-ITT Analysis Set Bacteroides fragilis	13 Participants	7 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: Micro-ITT Analysis Set Bacteroides thetaiotaomicron	8 Participants	1 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC visit (Day 28)

Population: Micro-ITT analysis set is a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Only those pathogens are reported which had more than or equal to 10 isolates for either treatment group.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Favorable Microbiological Response Per-Pathogen at at TOC Visit: Micro-ITT Analysis Set Escherichia coli	91 Participants	44 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at at TOC Visit: Micro-ITT Analysis Set Klebsiella pneumoniae	14 Participants	15 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at at TOC Visit: Micro-ITT Analysis Set Pseudomonas aeruginosa	12 Participants	3 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at at TOC Visit: Micro-ITT Analysis Set Streptococcus anginosus group	12 Participants	4 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at at TOC Visit: Micro-ITT Analysis Set Bacteroides fragilis	14 Participants	7 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at at TOC Visit: Micro-ITT Analysis Set Bacteroides thetaiotaomicron	8 Participants	1 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT (Within 24 hours after last infusion on Day 14)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Only those pathogens are reported which had more than or equal to 10 isolates for either treatment group.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: ME Analysis Set Escherichia coli	90 Participants	44 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: ME Analysis Set Klebsiella pneumoniae	17 Participants	17 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: ME Analysis Set Streptococcus anginosus group	13 Participants	3 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: ME Analysis Set Bacteroides fragilis	13 Participants	6 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at EOT Visit: ME Analysis Set Bacteroides thetaiotaomicron	8 Participants	1 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC visit (Day 28)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Only those pathogens are reported which had more than or equal to 10 isolates for either treatment group.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Favorable Microbiological Response Per-Pathogen at TOC Visit: ME Analysis Set Escherichia coli	86 Participants	40 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at TOC Visit: ME Analysis Set Klebsiella pneumoniae	13 Participants	14 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at TOC Visit: ME Analysis Set Streptococcus anginosus group	12 Participants	3 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at TOC Visit: ME Analysis Set Bacteroides fragilis	14 Participants	6 Participants
Number of Participants With Favorable Microbiological Response Per-Pathogen at TOC Visit: ME Analysis Set Bacteroides thetaiotaomicron	8 Participants	1 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT (Within 24 hours after last infusion on Day 14)

Population: Micro-ITT analysis set=subset of ITT analysis set \& included all participants who had at least 1 Gram-negative baseline pathogen from an adequate specimen obtained prior to start of study treatment.Here, 'Overall Number of Participants Analyzed' signifies participants included in micro-ITT analysis set and contributed data to table. Number Analyzed=number of participants evaluable for specified rows and participants with per participant response of indeterminate were excluded from analysis.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable microbiological response by pathogen resistance type (ATM non-susceptible and Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ATM non-susceptible: CLSI	68.8 Percentage of participants	78.6 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ATM non-susceptible : EUCAST	76.2 Percentage of participants	80.6 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Meropenem non-susceptible : CLSI	57.1 Percentage of participants	66.7 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Meropenem non-susceptible : EUCAST	57.1 Percentage of participants	66.7 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ESBL-positive	78.3 Percentage of participants	84.2 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Carbapenamase-positive	50.0 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Serene Carbapenamase-positive	33.3 Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Metallo-beta-lactamase-positive	75.0 Percentage of participants	0.0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC visit (Day 28)

Population: Micro-ITT analysis set=subset of ITT analysis set \& included all participants who had at least 1 Gram-negative baseline pathogen from an adequate specimen obtained prior to start of study treatment. Here, 'Overall Number of Participants Analyzed' signifies participants included in micro-ITT analysis set and contributed data to table. Number Analyzed=number of participants evaluable for specified rows and participants with per participant response of indeterminate were excluded from analysis.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable microbiological response by pathogen resistance type (ATM non-susceptible and Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ATM non-susceptible: CLSI	59.4 Percentage of participants	59.3 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ATM non-susceptible: EUCAST	66.7 Percentage of participants	60.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Meropenem non-susceptible: CLSI	28.6 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Meropenem non-susceptible : EUCAST	28.6 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ESBL-positive	73.9 Percentage of participants	73.7 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Carbapenamase-positive	20.0 Percentage of participants	0.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Serene Carbapenamase-positive	16.7 Percentage of participants	0.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Metallo-beta-lactamase-positive	25.0 Percentage of participants	0.0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT (Within 24 hours after last infusion on Day 14)

Population: ME analysis set =all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable microbiological response by pathogen resistance type (ATM non-susceptible, Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set ATM non-susceptible: CLSI	70.0 Percentage of participants	80.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set ATM non-susceptible: EUCAST	75.0 Percentage of participants	82.1 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Meropenem non-susceptible: CLSI	53.8 Percentage of participants	62.5 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Meropenem non-susceptible: EUCAST	53.8 Percentage of participants	62.5 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set ESBL-positive	77.3 Percentage of participants	88.2 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Carbapenamase-positive	44.4 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Serene Carbapenamase-positive	33.3 Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Metallo-beta-lactamase-positive	66.7 Percentage of participants	0.0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC visit (Day 28)

Population: ME analysis set =all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable microbiological response by pathogen resistance type (ATM non-susceptible, Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set ATM non-susceptible: CLSI	60.0 Percentage of participants	60.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set ATM non-susceptible: EUCAST	66.7 Percentage of participants	60.7 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Meropenem non-susceptible: CLSI	30.8 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Meropenem non-susceptible: EUCAST	30.8 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set ESBL-positive	72.7 Percentage of participants	76.5 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Carbapenamase-positive	22.2 Percentage of participants	0.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Serene Carbapenamase-positive	16.7 Percentage of participants	0.0 Percentage of participants
Percentage of Participants With Favorable Per-Participant Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Metallo-beta-lactamase-positive	33.3 Percentage of participants	0.0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT (Within 24 hours after last infusion on Day 14)

Population: Micro-ITT analysis set is a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable per-pathogen microbiological response by pathogen resistance type (ATM non-susceptible, Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ATM non-susceptible: CLSI	68.3 Percentage of participants	77.4 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ATM non-susceptible: EUCAST	73.3 Percentage of participants	78.4 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Meropenem non-susceptible: CLSI	60.0 Percentage of participants	75.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Meropenem non-susceptible : EUCAST	59.1 Percentage of participants	72.7 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set ESBL-positive	72.0 Percentage of participants	80.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Carbapenemase-positive	61.5 Percentage of participants	50.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Serine-carbapenemase-positive	42.9 Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: Micro-ITT Analysis Set Metallo-beta-lactamase-positive	71.4 Percentage of participants	66.7 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC visit (Day 28)

Population: Micro-ITT analysis set is a subset of the ITT analysis set and included all participants who had at least one Gram-negative baseline pathogen from an adequate specimen obtained prior to the start of study treatment. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable per-pathogen microbiological response by pathogen resistance type (ATM non-susceptible, Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=177 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=94 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ATM non-susceptible: CLSI	58.5 Percentage of participants	58.1 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ATM non-susceptible: EUCAST	63.3 Percentage of participants	56.8 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Meropenem non-susceptible: CLSI	30.0 Percentage of participants	41.7 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Meropenem non-susceptible: EUCAST	31.8 Percentage of participants	36.4 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set ESBL-positive	72.0 Percentage of participants	70.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Carbapenemase-positive	23.1 Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Serine-carbapenemase-positive	14.3 Percentage of participants	0.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: Micro-ITT Analysis Set Metallo-beta-lactamase-positive	28.6 Percentage of participants	66.7 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At EOT (Within 24 hours after last infusion on Day 14)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable per-pathogen microbiological response by pathogen resistance type (ATM non-susceptible, Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Serine-carbapenemase-positive	50. Percentage of participants	33.3 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set ATM non-susceptible: CLSI	75.8 Percentage of participants	80.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set ATM non-susceptible: EUCAST	78.6 Percentage of participants	82.8 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Meropenem non-susceptible: CLSI	62.5 Percentage of participants	62.5 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Meropenem non-susceptible: EUCAST	62.5 Percentage of participants	62.5 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set ESBL-positive	77.3 Percentage of participants	88.2 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Carbapenemase-positive	70.0 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at EOT Visit: ME Analysis Set Metallo-beta-lactamase-positive	100.0 Percentage of participants	0.0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: At TOC visit (Day 28)

Population: The ME analysis set included all participants commonly included in both micro-ITT and CE analysis sets and included participants who had at least 1 etiologic pathogen from an adequate baseline culture regardless of susceptibility to study agents. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Participants were determined to have a favorable microbiological response if all baseline pathogens for that participant had a favorable outcome (eradicated or presumed eradicated). Eradication: Absence of causative pathogen from an appropriately obtained specimen at the site of infection. Presumed eradication: repeat culture of specimens were not performed/clinically indicated in a participant who had a clinical response of cure. Percentage of participants with favorable per-pathogen microbiological response by pathogen resistance type (ATM non-susceptible, Meropenem non-susceptible based on EUCAST criteria and CLSI criteria, ESBL-positive, Carbapenemase-positive, Serene Carbapenemase and Metallo-beta-lactamase-positive) is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=149 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=79 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set ATM non-susceptible: CLSI	63.6 Percentage of participants	60.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set ATM non-susceptible: EUCAST	66.7 Percentage of participants	62.1 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Meropenem non-susceptible: CLSI	31.3 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Meropenem non-susceptible : EUCAST	31.3 Percentage of participants	25.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set ESBL-positive:	77.3 Percentage of participants	76.5 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Carbapenemase-positive:	30.0 Percentage of participants	0.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Serine-carbapenemase-positive	16.7 Percentage of participants	0.0 Percentage of participants
Percentage of Participants With Favorable Per-Pathogen Microbiological Response by Pathogen Resistance Type at TOC Visit: ME Analysis Set Metallo-beta-lactamase-positive:	50.0 Percentage of participants	0.0 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to Day 28

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug. A composite scoring system was never developed and therefore there is no data to report for this outcome measure.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to Day 28

Population: CE analysis set. A composite scoring system was never developed and therefore there is no data to report for this outcome measure.

CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization up to 14 days

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug.

Percentage of participants who died on or before 14 days from randomization is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Percentage of Participants Who Died on or Before 14 Days From Randomization: ITT Analysis Set	2.8 Percentage of participants	3.6 Percentage of participants

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization up to Day 28

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

The total length of hospital stay was defined as the total number of calendar days on which the participant was in the hospital from the date of randomization up to and including the specified time point of TOC.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=281 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=139 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Total Length of Hospital Stay up to TOC Visit: ITT Analysis Set	13.6 Days Standard Deviation 9.42	12.9 Days Standard Deviation 8.05

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization up to Day 28

Population: CE analysis set.

The total length of hospital stay was defined as the total number of calendar days on which the participant was in the hospital from the date of randomization up to and including the specified time point of TOC. CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=213 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=105 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Total Length of Hospital Stay up to TOC Visit: CE Analysis Set	13.0 Days Standard Deviation 8.55	12.3 Days Standard Deviation 7.29

OTHER_PRE_SPECIFIED outcome

Timeframe: From first dose of study treatment until last dose of treatment (Up to 14 days)

Population: The safety analysis set included all participants who received any amount of study treatment.

The duration of therapy in calendar days were calculated as follows: Date of last dose of study drug - date of first dose of study drug +1.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=275 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=137 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Duration of Study Treatment	8.5 Days Standard Deviation 3.52	8.9 Days Standard Deviation 3.17

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

The total length of ICU stay was defined as the total number of calendar days on which the participant was in ICU for the period from date of randomization until the TOC visit.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=80 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=39 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Length of Intensive Care Unit (ICU) Stay: ITT Analysis Set	11.6 Days Standard Deviation 9.10	12.5 Days Standard Deviation 9.45

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: CE analysis set. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

The total length of ICU stay was defined as the total number of calendar days on which the participant was in ICU for the period from date of randomization until the TOC visit. CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=54 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=24 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Length of Intensive Care Unit (ICU) Stay: CE Analysis Set	12.1 Days Standard Deviation 9.23	12.4 Days Standard Deviation 9.38

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug.

Number of participants admitted to the ICU up to TOC were reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=282 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=140 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants Admitted to the ICU: ITT Analysis Set	80 Participants	39 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: CE analysis set.

The number of participants admitted to the ICU were reported in this outcome measure. CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=213 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=105 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants Admitted to the ICU: CE Analysis Set	54 Participants	24 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Number of participants with mechanical ventilation were reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=74 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=36 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Mechanical Ventilation: ITT Analysis Set	43 Participants	21 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: CE analysis set. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Number of participants with mechanical ventilation were reported in this outcome measure. CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=45 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=22 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Mechanical Ventilation: CE Analysis Set	24 Participants	13 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Duration of mechanical ventilation was defined as the total number of calendar days on which the participant required mechanical ventilation from the date of randomization up to TOC.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=43 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=21 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Duration of Mechanical Ventilation in HAP/VAP Participants: ITT Analysis Set	14.2 Days Standard Deviation 9.94	16.7 Days Standard Deviation 11.16

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: CE analysis set. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Duration of mechanical ventilation was defined as the total number of calendar days on which the participant required mechanical ventilation from the date of randomization up to TOC. CE analysis set: all participants in ITT analysis set; met criteria for cIAI, or HAP/VAP; received at least 48 hours of study treatment or \<48 hours of treatment before discontinuing study drug due to AE; no concomitant antibiotics for any baseline pathogens between first dose and TOC (except protocol-allowed antibiotics); no prior antibiotics other than allowed per protocol; no important protocol deviations; no clinical outcome of indeterminate at TOC; no monomicrobial infections due to non-eligible pathogens and did not have only Gram-positive pathogens.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=24 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=13 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Duration of Mechanical Ventilation in HAP/VAP Participants: CE Analysis Set	17.4 Days Standard Deviation 8.99	19.5 Days Standard Deviation 11.16

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: The ITT analysis set included all randomized participants regardless of receipt of study drug. All participants reported under 'Overall Number of Participants Analyzed' contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Unplanned surgical interventions was defined as those occurring after the initial qualifying surgical intervention and prior to the TOC visit. Number of cIAI participants with unplanned surgical intervention according to clinical response categories of cure and failure is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=193 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=100 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Unplanned Surgical Interventions in Complicated Intra-abdominal Infections (cIAI) Participants: ITT Analysis Set Cure	1 Participants	1 Participants
Number of Participants With Unplanned Surgical Interventions in Complicated Intra-abdominal Infections (cIAI) Participants: ITT Analysis Set Failure	5 Participants	10 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: From randomization until TOC visit (Up to Day 28)

Population: CE analysis set. All participants reported under 'Overall Number of Participants Analyzed' include participants evaluable for this outcome measure and contributed data to the table but may not have evaluable data for every row. Here, 'Number Analyzed' signifies number of participants evaluable for specified rows.

Unplanned surgical interventions was defined as those occurring after the initial qualifying surgical intervention and prior to the TOC visit. Number of cIAI participants with unplanned surgical intervention according to clinical response categories of cure and failure is reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Aztreonam-avibactam ± Metronidazole n=168 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=83 Participants Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Number of Participants With Unplanned Surgical Interventions in cIAI Participants: CE Analysis Set Cure	1 Participants	1 Participants
Number of Participants With Unplanned Surgical Interventions in cIAI Participants: CE Analysis Set Failure	5 Participants	9 Participants

Adverse Events

Aztreonam-avibactam ± Metronidazole

Serious events: 53 serious events

Other events: 113 other events

Deaths: 20 deaths

Meropenem± Colistimethate

Serious events: 25 serious events

Other events: 45 other events

Deaths: 11 deaths

Serious adverse events

Other adverse events

Additional Information

Pfizer ClinicalTrials.gov Call Center

Pfizer Inc.

Phone: 1-800-718-1021

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee Pfizer has the right to review disclosures, requesting a delay of less than 60 days. Investigator will postpone single center publication until after disclosure of pooled data (all sites), less than 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential information other than study results.
Publication restrictions are in place

Restriction type: OTHER

Measure	Aztreonam-avibactam ± Metronidazole n=275 participants at risk Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive a loading dose of aztreonam-avibactam (ATM-AVI) by intravenous (IV) infusion over 30 minutes, immediately followed by an extended loading dose of ATM-AVI by IV infusion over 3 hours on Day 1. Participants were administered a maintenance dose of ATM-AVI by IV infusion over 3 hours on Days 2 to 14. Participants with cIAI also received metronidazole (MTZ) 500 milligrams (mg) IV every 8 hours.	Meropenem± Colistimethate n=137 participants at risk Participants hospitalized with cIAI or NP (including HAP and VAP) were randomized to receive 1000 mg meropenem every 8 hours by IV infusion. A higher dose of 2000 mg was given by IV infusion over 180 minutes if carbapenem resistant pathogen was strongly suspected. Participants were administered colistimethate sodium at investigator's discretion.
Blood and lymphatic system disorders Anaemia	7.3% 20/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	5.1% 7/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Cardiac disorders Atrial fibrillation	2.2% 6/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	0.73% 1/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Gastrointestinal disorders Abdominal distension	1.8% 5/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.2% 3/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Gastrointestinal disorders Abdominal pain	2.2% 6/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.9% 4/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Gastrointestinal disorders Constipation	2.9% 8/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	1.5% 2/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Gastrointestinal disorders Diarrhoea	5.8% 16/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	3.6% 5/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Gastrointestinal disorders Nausea	3.6% 10/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.2% 3/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Gastrointestinal disorders Vomiting	3.6% 10/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	1.5% 2/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
General disorders Injection site reaction	0.36% 1/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.9% 4/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
General disorders Pyrexia	5.1% 14/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	3.6% 5/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Hepatobiliary disorders Hepatic function abnormal	4.0% 11/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.2% 3/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Hepatobiliary disorders Hypertransaminasaemia	2.2% 6/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	0.73% 1/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Investigations Alanine aminotransferase increased	6.5% 18/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	5.1% 7/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Investigations Aspartate aminotransferase increased	5.5% 15/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	3.6% 5/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Investigations Blood alkaline phosphatase increased	0.36% 1/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.2% 3/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Metabolism and nutrition disorders Hypokalaemia	5.8% 16/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.9% 4/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Respiratory, thoracic and mediastinal disorders Pleural effusion	2.5% 7/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	0.73% 1/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Skin and subcutaneous tissue disorders Decubitus ulcer	2.2% 6/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	0.73% 1/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Skin and subcutaneous tissue disorders Rash	2.5% 7/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	0.00% 0/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Vascular disorders Hypertension	1.8% 5/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	2.2% 3/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.
Vascular disorders Phlebitis	2.2% 6/275 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.	0.00% 0/137 • All-cause mortality: From signing of informed consent until end of late follow up visit (Day 45); non-SAEs and SAEs: From start of study treatment until end of late follow-up visit (Up to Day 45). All-cause mortality is presented for ITT analysis set and non-SAEs and SAEs are presented for Safety analysis set.