P1, DDI & MAD PK and Safety Study of Xeruborbactam Oral Prodrug in Combo With Ceftibuten in Healthy Participants

Inclusion Criteria:

Participants will be eligible to be included in the study only if all of the following criteria apply:

Age

1. Participant must be a healthy adult male or female, 18 to 55 years of age (inclusive) at the time of screening. Type of Participant and Disease Characteristics

2. Participants who are overtly medically healthy with clinically insignificantscreening results (eg, laboratory profiles, medical histories, ECGs, physicalexamination) as assessed by the investigator, sub-investigator, or medical officer. Weight

3. Body mass index (BMI) ≥ 18.5 and ≤ 29.9 (kg/m2) and weight between 55.0 and 100.0 kg (inclusive). Note: BMI = kg/m2 where kg is a weight in kilograms and m2 is a heightin meters squared. Sex and Contraceptive/Barrier Requirements

4. Contraceptive use by men and women should be consistent with local regulationsregarding the methods of contraception for those participating in clinical studies. Male participants: If male, agree to be sexually abstinent or agree to use 2 approved methods ofcontraception (refer to inclusion criterion #5) when engaging in sexual activityfrom study check-in through 30 days following the last administration of the studydrug, and to not donate sperm during this same period of time. If the sexual partneris surgically sterile, contraception is not necessary.

5. Female participants: Females of childbearing potential must either be sexually abstinent for 14 daysprior to Day 1 and agree to remain so through 30 days following the lastadministration of the study drug, OR have been using (or agree to use) 2 of thefollowing acceptable methods of birth control for the times specified:

6. Intra-uterine device (IUD) in place for at least 3 months prior to Day 1through 30 days following the final dosing of the study drug

7. Barrier method (condom or diaphragm) for at least 14 days prior to Day 1through 30 days following the final dosing of the study drug

8. Stable hormonal contraceptive for at least 3 months prior to Day 1 and barriermethod (condom or diaphragm) for at least 14 days prior to Day 1 through 30days following final dosing of the study drug

9. Surgical sterilization (vasectomy) of partner at least 6 months prior to Day 1 Informed Consent

10. Capable of giving signed informed consent as described in Appendix 1 InformedConsent Form (Section 10.1.3) that includes compliance with the requirements andrestrictions listed in the informed consent form (ICF) and in this protocol.

Exclusion Criteria:

Participants will be excluded from the study if any of the following criteria apply:

Medical Conditions

1. History or presence of significant cardiovascular, pulmonary, hepatic, renal,hematological, gastrointestinal, endocrine, immunologic, dermatologic, neurological,or psychiatric disease.

2. Documented hypersensitivity reaction or anaphylaxis to any medication, includingceftibuten or other beta-lactam antibiotics (e.g. cephalosporins, penicillins,carbapenems or monobactams) or any excipients used in this formulation.

3. Positive testing for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), or hepatitis C virus (HCV).

4. Females who are pregnant or lactating.

5. Surgery within the past 3 months prior to Day 1 determined by the investigator,sub-investigator, or medical officer to be clinically relevant.

6. Any acute illness within 30 days prior to Day 1.

7. Any other condition or prior therapy, which, in the opinion of the investigator,sub-investigator, or medical officer would make the participant unsuitable for thisstudy. Prior/Concomitant Therapy

8. Use of any prescription medication (with the exception of hormonal contraceptives orhormone replacement therapy for females) within 14 days prior to Day 1.

9. Use of any over-the-counter medication, including herbal products, probiotics andvitamins, within the 7 days prior to Day 1. Up to 2 grams per day of paracetamol isallowed for acute events at the discretion of the investigator, sub-investigator, ormedical officer.

10. Use of antacids, H2 receptor blockers or proton pump inhibitors 7 days prior to Day

11. This includes calcium carbonate. Prior/Concurrent Clinical Study Experience

12. Participation in another investigational clinical trial within 30 days prior to Day 1 or within 5 half-lives of the previous investigational drug, whichever is longer. Diagnostic Assessments

13. QTc corrected according to Fridericia's formula (QTcF) interval > 450 msec for malesand > 470 for females or history of prolonged QT syndrome at screening or check-in (Day -1).

14. Calculated creatinine clearance < 80 mL/min (Cockcroft-Gault method) at screening orcheck-in (Day -1).

15. Any clinically significant abnormalities in laboratory values at screening orcheck-in (Day -1), in particular:

16. White blood cell count < 3,000/mm3, hemoglobin < 11g/dL

17. Absolute neutrophil count < 1,200/mm3 or platelet count < 120,000/mm3

18. Liver function abnormalities at screening or check-in (Day -1) (defined by anelevation in bilirubin, AST, or ALT > ULN for participants based on age andsex) Other Exclusion Criteria

19. Blood donation or significant blood loss (ie, > 500 mL) within 56 days prior to Day

21. Plasma donation within 7 days prior to Day 1.

22. Positive urine drug/alcohol testing at screening or check-in (Day -1).

23. History or presence of alcoholism or drug abuse within the 2 years prior to Day 1.

24. Use of more than 5 packs/week of cigarettes (or equivalent amount ofnicotine-containing product) within 6 months prior to Day 1. Use of all nicotinecontaining products 48 hours prior to admission to clinical research unit.Participants must agree to refrain from smoking for the duration of the study.

25. Excessive intake of alcohol, defined as an average daily intake of > 2 standarddrinks for women and > 4 standard drinks for men, (standard drink is the equivalentto 4 oz of wine (approximately 12% abv), 12 oz of regular beer (approximately 5%abv), or 1.5 oz of spirits (80 proof).