Study to Assess the Efficacy, Safety and Pharmacokinetics of Orally Administered Tebipenem Pivoxil Hydrobromide (SPR994) Compared to Intravenous Ertapenem in Participants With Complicated Urinary Tract Infection (cUTI) or Acute Pyelonephritis (AP)

Inclusion Criteria

• Male and female participants at least 18 years of age.
• Able to provide informed consent.
• Able to ingest oral tablets for the anticipated treatment duration. If present at baseline, nausea and/or vomiting should have been mild or well-controlled with antiemetic therapy, in order to tolerate oral study drug.
• Have a diagnosis of cUTI or AP as defined below:

a. cUTI definition:

At least Two of the following signs and symptoms:

i. Chills, rigors, or fever; fever must be observed and documented by a health care provider (oral, tympanic, rectal or core temperature >38.0°C [>100.4°F])

ii. Dysuria, urgency to void, or increased urinary frequency

iii. Nausea or vomiting, as reported by the participants

iv. Lower abdominal, suprapubic, or pelvic pain

And at least One of the following risk factors for cUTI:

i. Implanted urinary tract instrumentation (e.g., nephrostomy tube, ureteric stents, or other urinary tract prosthetic material), ongoing intermittent bladder catheterization, or presence of an indwelling bladder catheter (Note: bladder catheters that have been in place for >24 hours prior to Screening must be removed or replaced prior to collection of the Screening urine for urinalysis and culture, unless removal or replacement is considered unsafe or contraindicated).

ii. Current known functional or anatomical abnormality of the urogenital tract, including anatomic abnormalities of the urinary tract, neurogenic bladder, or post-void residual urine volume of ≥ 100 mL within the past 6 months.

iii. Complete or partial obstructive uropathy (e.g., nephrolithiasis, tumor, fibrosis, urethral stricture) that is expected to be medically or surgically treated during study drug therapy (prior to end of the treatment [EOT]).

iv. Known intrinsic renal disease with blood urea nitrogen (BUN) >20 mg/deciliter (dL), or blood urea >42.8 mg/dL, or serum creatinine (Cr) >1.4 mg/dL.

v. Urinary retention, including urinary retention in men due to previously diagnosed benign prostatic hyperplasia (BPH).

b. AP definition: Acute flank pain (onset within 7 days prior to randomization) or costovertebral angle tenderness on physical examination.

And at least One of the following signs and symptoms:

i. Chills, rigors, or fever; fever must be observed and documented by a health care provider (oral, tympanic, rectal or core temperature >38.0°C [>100.4°F]).

ii. Peripheral white blood cell count (WBC) >10,000/mm3 or bandemia (≥15% immature polymorphonuclear neutrophils (PMNs), regardless of WBC count).

iii. Nausea or vomiting, as reported by the participants.

iv. Dysuria, urgency to void, or increased urinary frequency.

Note: Participants who meet the definition for cUTI (Inclusion Criterion 4a) and also have flank pain or costovertebral tenderness should be randomized as cUTI rather than AP.

• Have an adequate urine specimen for evaluation and culture obtained within 24 h prior to randomization with evidence of pyuria that includes at least one of the following:
• At least 10 WBCs per high power field (hpf) in urine sediment.
• At least 10 WBCs per cubic millimeter (mm3) in unspun (non-centrifuged) urine.
• Positive leukocyte esterase (LE) on urinalysis. Note: Participants could be randomized and administered investigational product (IP) prior to knowledge of urine culture results.
• Expectation, in the judgment of the Investigator, that the participant would survive with effective antibiotic therapy and appropriate supportive care for the anticipated duration of the study.
• Willing to comply with all the study activities and procedures throughout the duration of the study.
• Participants were required to use a highly-effective method of birth control; male participants were required to use an effective barrier method of contraception from Screening through LFU and for 90 days following the last dose if sexually active with a female of childbearing potential (FOCP); female participants must not have been