Study to Assess the Pharmacokinetics, Safety and Tolerability of Aztreonam-Avibactam in Healthy Chinese Participants.

Cmax was the maximum observed plasma concentration and was directly observed from data. Concentration values below the lower limit of quantification (LLQ) were set to zero. Geometric Mean analysis was on the log scale. Zero values were not included in geometric mean and geometric coefficient of variation calculation. The geometric coefficient of variation is expressed in percentage.

Cmax was the maximum observed plasma concentration and was directly observed from data. Concentration values below the lower limit of quantification (LLQ) were set to zero. Geometric Mean analysis was on the log scale. Zero values were not included in geometric mean and geometric coefficient of variation calculation. The geometric coefficient of variation is expressed in percentage.

The area under the plasma drug concentration-time curve (AUC) was estimated from time 0 to 6 hours post dose. AUC6 was computed using the Linear/Log trapezoidal method. The geometric coefficient of variation is expressed in percentage.

The area under the plasma drug concentration-time curve (AUC) was estimated from time 0 to 6 hours post dose. AUC6 was computed using the Linear/Log trapezoidal method. The geometric coefficient of variation is expressed in percentage.

AUClast is area under the plasma concentration time-curve from zero (pre-dose) to the last measured concentration. The geometric coefficient of variation is expressed in percentage.

AUClast is area under the plasma concentration time-curve from zero (pre-dose) to the last measured concentration. The geometric coefficient of variation is expressed in percentage.

AUC24 was defined as area under the plasma concentration-time profile from time zero to 24 hours post dose. The geometric coefficient of variation is expressed in percentage.

AUC24 was defined as area under the plasma concentration-time profile from time zero to 24 hours post dose. The geometric coefficient of variation is expressed in percentage.

AUCinf was defined as area under the plasma concentration-time curve from time zero to infinity. The geometric coefficient of variation is expressed in percentage.

AUCinf was defined as area under the plasma concentration-time curve from time zero to infinity. The geometric coefficient of variation is expressed in percentage.

AUCtau was defined as area under the concentration-time profile from time 0 to time tau. The geometric coefficient of variation is expressed in percentage.

AUCtau was defined as area under the concentration-time profile from time 0 to time tau. The geometric coefficient of variation is expressed in percentage.

AUC24,ss was defined as total daily area under the plasma concentration-time profile from time 0 to 24 hours at steady-state. The geometric coefficient of variation is expressed in percentage.

AUC24,ss was defined as total daily area under the plasma concentration-time profile from time 0 to 24 hours at steady-state. The geometric coefficient of variation is expressed in percentage.

CLr was calculated as cumulative amount of drug recovered unchanged in urine during the dosing interval (Ae) divided by area under the plasma concentration time-curve from time zero to end of dosing interval (AUCtau). AUCtau was defined as area under the concentration-time profile from time 0 to time tau. The geometric coefficient of variation is expressed in percentage.

CLr was calculated as cumulative amount of drug recovered unchanged in urine during the dosing interval (Ae) divided by area under the plasma concentration time-curve from time zero to end of dosing interval (AUCtau). AUCtau was defined as area under the concentration-time profile from time 0 to time tau. The geometric coefficient of variation is expressed in percentage.

Plasma terminal elimination half-life (T1/2) is the time measured for the plasma concentration to decrease by one half at the terminal phase.

Plasma terminal elimination half-life (T1/2) is the time measured for the plasma concentration to decrease by one half at the terminal phase.

Apparent volume of distribution (Vz) was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired blood concentration of a drug. Vss was the Vz at steady-state. The geometric coefficient of variation is expressed in percentage.

Vz was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired blood concentration of a drug. Vss was the Vz at steady-state. The geometric coefficient of variation is expressed in percentage.

Vz was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired blood concentration of a drug. The geometric coefficient of variation is expressed in percentage.

Vz was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired blood concentration of a drug. The geometric coefficient of variation is expressed in percentage.

CL was a quantitative measure of the rate at which a drug substance was removed from the body. The geometric coefficient of variation is expressed in percentage.

CL was a quantitative measure of the rate at which a drug substance was removed from the body. The geometric coefficient of variation is expressed in percentage.

Tmax was defined as time to reach maximum observed plasma concentration.

Tmax was defined as time to reach maximum observed plasma concentration.

Accumulation ratio based on maximum plasma concentration (Rac,cmax) was calculated as: Rac,Cmax = Cmax at steady state (Day 4) divided by Cmax at first dose (Day 1). The geometric coefficient of variation is expressed in percentage.

Accumulation ratio based on maximum plasma concentration (Rac,cmax) was calculated as: Rac,Cmax = Cmax at steady state (Day 4) divided by Cmax at first dose (Day 1). The geometric coefficient of variation is expressed in percentage.

Rac was obtained from AUCtau at steady state (Day 4) divided by AUCtau after single dose (Day 1). AUCtau was defined as area under the concentration-time profile from time 0 to time tau. The geometric coefficient of variation is expressed in percentage.

Rac was obtained from AUCtau at steady state (Day 4) divided by AUCtau after single dose (Day 1). AUCtau was defined as area under the concentration-time profile from time 0 to time tau. The geometric coefficient of variation is expressed in percentage.

An AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. Treatment-emergent adverse event (TEAE) means event between first dose of study treatment and up to 30 days after last dose that were absent before treatment or that worsened relative to pretreatment state. An SAE was an AE resulting in any of death; inpatient hospitalization; life-threatening experience; disability; congenital anomaly or deemed significant for any other reason. Symptoms of infusion-related reactions (IRRs) may include, but were not limited to, fever, chills, flushing, hypotension, dyspnea, wheezing, back pain, abdominal pain, and urticaria. Grade 3: severe or medically significant but not immediately life-threatening, hospitalization or prolongation of existing hospitalization indicated, disabling, limiting self-care ADL; Grade 4: life-threatening consequence, urgent intervention indicated; Grade 5: death related to AE.

Criteria for vital signs abnormalities: increase or decrease from baseline in supine Systolic Blood Pressure (SBP) >=30 mm Hg and increase or decrease from baseline in supine Diastolic Blood Pressure (DBP) >=20 mm Hg.

ECG categorical summarization criteria: 1. PR interval (the interval between the start of the P wave and the start of the QRS complex, corresponding to the time between the onset of the atrial depolarization and onset of ventricular depolarization): a) greater than or equal to (>=) 300 millisecond (msec), b) >=25% increase when baseline is > 200 msec or >=50% increase when baseline is less than or equal to (<=) 200 msec.

• QRS duration (time from ECG Q wave to the end of the S wave corresponding to ventricle depolarization): a) >=140 msec, b) >=50% increase from baseline.

• QTcF interval (QT corrected using the Fridericia formula): a) >450 msec and <=480 msec, b) >480 msec and <=500 msec, c) >500 msec, d) >30 msec and <=60 msec increase from baseline, e) >60 msec increase from baseline.

Following laboratory parameters were assessed against pre-defined abnormality criteria: hematology (basophils); clinical chemistry (urate); urinalysis (urine hemoglobin, nitrite, urine erythrocytes).