• History of UTI in the past 12 months and prior or current uUTI caused by AMR E. coli (as single pathogen or part of polymicrobial infection where E. coli is the predominant pathogen). Please note that the current infection can be used to meet the requirement of AMR E. coli documentation.

• Able to supply a mid-stream, clean catch urine sample for microbiological analysis.

• Active acute uUTI infection defined by:

• a. Evidence of pyuria: i. \>10 white blood cell (WBC)/mL3 on microscopic evaluation of spun, clean, mid-stream urine specimen or \>3 WBC/high power field on unspun clean, mid-stream urine specimen, AND/OR ii. Dipstick analysis of a clean, mid-stream urine specimen positive for leukocytes, AND b. At least 2 of the following signs or symptoms of UTI: dysuria, urinary frequency, urinary urgency, or suprapubic pain

• Willing to comply with all aspects of study design including study restrictions, blood, urine, and stool sampling, and scheduled study visits.

• All sexually active female patients of childbearing potential must use highly effective contraception during the study and until 2 weeks after the last dose of study drug treatment.

• Agrees to STOP continuous low dose antimicrobial prophylaxis and/or will maintain the same practices for post-coital antimicrobial prophylaxis to prevent UTI, as during the prior 12-months, for the entire study duration (throughout the 6-month follow-up period or study discharge).

• Agrees to not use any prescription or non-prescription medication for the microbiological or symptomatic treatment of the presenting acute uUTI for the first 10 days of the study.

• Capable of providing their own signed informed consent form (ICF) prior to any study-related procedures being performed.

• If participating in Part 1 of the study, agrees to fast for ≥2 h prior to first dose of study drug on Day 1/Visit 1 except for drinking 240 mL of water with study drug administration.