Efficacy/Safety of Meropenem-Vaborbactam Compared to Piperacillin-Tazobactam in Adults With cUTI and AP

Inclusion Criteria

• A signed informed consent form, the ability to understand the study conduct and tasks that are required for study participation, and a willingness to cooperate with all tasks, tests, and examinations as required by the protocol.
• Male or female ≥18 years of age.
• Weight ≤185 kilograms (kg).
• Expectation, in the judgment of the Investigator, that the participant's cUTI or AP requires initial treatment with at least 5 days of IV antibiotics.
• Documented or suspected cUTI or AP as defined below:

cUTI

Signs or symptoms evidenced by at least 2 of the following:

• Chills, rigors, or fever (fever must be documented within 24 hours of the screening visit with a temperature of ≥38.0 degrees Celsius [°C] [≥100.4 degrees Fahrenheit (°F)] or rectal/core temperature ≥38.3°C [≥100.9°F], observed and documented by a health care provider);
• Elevated white blood cell count (>10, 000/ cubic millimeters [mm^3]) or left shift (>15% immature polymorphonuclear leukocytes [PMNs]);
• Nausea or vomiting;
• Dysuria, increased urinary frequency, or urinary urgency;
• Lower abdominal pain or pelvic pain

Pyuria evidenced by 1 of the following:

• Positive leukocyte esterase (LCE) on urinalysis;
• White blood cell count ≥10 cells/mm^3 in unspun urine;
• White blood cell count ≥10 cells/high-power field (hpf) in urine sediment

At least 1 of the following associated risks:

• Indwelling urinary catheter;
• Neurogenic bladder with presence or history of urine residual volume of ≥100 mL;
• Obstructive uropathy (such as, nephrolithiasis, tumor, fibrosis) that is expected to be medically or surgically treated within 48 hours post randomization;
• Azotemia due to intrinsic renal disease;
• Urinary retention in men due to previously diagnosed benign prostatic hypertrophy

AP

Signs or symptoms evidenced by at least 2 of the following:

• Chills, rigors, or fever (fever must be documented within 24 hours of the screening visit with a temperature of ≥38.0°C [≥100.4°F] or rectal/core temperature ≥38.3°C [≥100.9°F], observed and documented by a health care provider);
• Elevated white blood cell count (>10, 000/mm^3), or left shift (>15% immature PMNs);
• Nausea or vomiting;
• Dysuria, increased urinary frequency, or urinary urgency;
• Flank pain;
• Costo-vertebral angle tenderness on physical examination

Pyuria evidenced by 1 of the following:

• Positive LCE on urinalysis;
• White blood cell count ≥10 cells/mm^3 in unspun urine;
• White blood cell count ≥10 cells/hpf in urine sediment
• Expectation, in the judgment of the Investigator, that any indwelling urinary catheter or instrumentation (including nephrostomy tubes and/or indwelling stents) will be removed or replaced (if removal is not clinically acceptable) before or as soon as possible, but not longer than 12 hours, after randomization.
• Expectation, in the judgment of the Investigator that the participant will survive with effective antibiotic therapy and appropriate supportive care for the anticipated duration of the study.
• Women of childbearing potential must have a negative pregnancy test before randomization and be willing to use a highly effective method of contraception between randomization and for 7 days after the completion of the study. A highly effective method of contraception includes 2 of the following: hormonal implants/patch, injectable hormones, oral hormonal contraceptives, prior bilateral oophorectomy, prior hysterectomy, prior bilateral tubal ligation, intra-uterine device, approved cervical ring, condom, true abstinence (if approved by the Investigator), or a vasectomized partner.
• Willingness to comply with all the study procedures, whether in the hospital or after discharge, for the duration of the study.

Exclusion Criteria

• Presence of any of the following conditions:
• Perinephric abscess;
• Renal corticomedullary abscess;
• Uncomplicated urinary tract infection;
• Polycystic kidney disease;
• Chronic vesicoureteral reflux;
• Previou