Inclusion Criteria:  Participant who is capable of giving signed, dated and timed informed consent (or by their legally acceptable representative) Participant aged 20 years or older Participant who is willing and able to comply with all scheduled visits, treatment plan, laboratory tests, and other study procedures Confirmation of infection by surgical intervention within 24 hours of entry: evidence of systemic inflammatory response; physical findings consistent with intra-abdominal infection; supportive radiologic imaging findings of intra-abdominal infections Intraoperative/postoperative enrollment with visual confirmation (presence of pus within the abdominal cavity) of an intra-abdominal infection associated with peritonitis  Exclusion Criteria:  Participant will undergo surgery for traumatic bowel perforation within 12 hours or perforation of gastroduodenal ulcers within 24 hours. Other intra-abdominal processes that are not infectious. Participant has abdominal wall abscess or bowel obstruction without perforation or ischemic bowel without perforation Participant whose surgery will include staged abdominal repair, or "open abdomen" technique, or marsupialization. Participant has evidence of sepsis with shock not responding to IV fluid challenge or anticipated to require the administration of vasopressors for >24 hours Participant has suspected intra-abdominal infections due to fungus, parasites (eg, amebic liver abscess), virus, or tuberculosis Participant is considered unlikely to survive the 6- to 8-week study period or has a rapidly progressive or terminal illness Participant is pregnant or breastfeeding. Participant has received systemic antibacterial agents within the 72-hour period prior to study entry except for cases specified in the protocol such that participant is considered to have failed the previous treatment regimen, or participant has received systemic antibiotic agents no more than 24 hours (no more than one daily dose) within the 72-hour period prior to study entry, etc. Estimated CrCL ≤50 mL/min calculated by Cockcroft-Gault method.