Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for creatinine clearance (CLCR), every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Cmax, maximum plasma concentration, of ceftolozane or tazobactam. Pharmacokinetic (PK) data analysis was performed by non-compartmental analysis (NCA) method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples and epithelial lining fluid (ELF) were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the epithelial lining fluid, ELF to plasma ratio of ceftolozane and tazobactam.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma and ELF drug concentrations were both determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Tmax, time of maximum plasma concentration, of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Clast, last quantifiable plasma concentration, of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Tlast, time of last quantifiable plasma concentration, of ceftolozane or tazobactam. PK data analysis was determined by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the AUC0-last, AUC from the first to time of the last dose, of ceftolozane or tazobactam. PK data analysis was determined by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the AUC0-∞, AUC from the time of the dose to infinity, of ceftolozane or tazobactam. PK data analysis was determined by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the t1/2, terminal elimination half-life, of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Vss, volume of distribution at steady state, of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

Mechanically ventilated participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the CL, plasma clearance, of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All mechanically ventilated participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Critically ill participants were not analyzed in this outcome measure.

An adverse event (AE) is any untoward medical occurrence in a participant administered a pharmaceutical product that does not necessarily have to have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product, whether or not related to the medicinal product.

All treated participants

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Cmax of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Tmax of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Clast of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Tlast of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the AUC0-last of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the AUC0-∞ of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the T1/2 of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the Vss of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.

Critically ill participants received a 60 minute infusion of ceftolozane/tazobactam, adjusted for CLCR, every 8 hours; then blood samples were collected at 1, 2, 4, 6, and 8 hours post start of the final infusion after the last dose of study drug in order to determine the CL of ceftolozane or tazobactam. PK data analysis was performed by NCA method using Phoenix WinNonlin version 6.3 or later.

All critically ill participants who received at least 1 dose of study drug at the correctly assigned dose level, and whose plasma drug concentration was determined. Mechanically ventilated participants were not analyzed in this outcome measure.