A Phase 1 interventional study of Xeruborbactam Oral Prodrug and Ceftibuten in Bacterial Infections, sponsored by Qpex Biopharma, Inc.. Completed at 1 site in Australia. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-12-12.
Sponsored by Qpex Biopharma, Inc. · Phase 1, Interventional, and Treatment
A Phase 1, Open-Label, Drug-drug Interaction, and Randomized, Double-blind, Controlled, Multiple-dose Pharmacokinetics and Safety Study of Xeruborbactam Oral Prodrug (QPX7831) in Combination with Ceftibuten in Healthy Adult Participants
Qpex Biopharma, Inc. is developing an oral dosage form that delivers Xeruborbactam, a new boron-based beta-lactamase inhibitor with activity against both serine and metallo-beta-lactamases, for oral treatment in combination with a beta-lactam antibiotic.
Ceftibuten is a cephalosporin antibiotic approved in the US for acute exacerbations of chronic bronchitis, acute bacterial otitis media and pharyngitis/tonsillitis.
This Phase 1 study will assess if a PK interaction exists between xeruborbactam oral prodrug and ceftibuten when given in combination at doses of each drug that have previously been shown to be safe. The study will also assess the safety of the combination with dosing over 10 days.
Study Objectives:
658 studies on the registry are indexed under Bacterial Infections; 100 are open to participants now.
This study's enrollment of 53 is below the median of 84 across 405 interventional studies indexed under Bacterial Infections.
Browse Bacterial Infections studies →Qpex Biopharma, Inc. is the lead sponsor of 10 studies on the registry; none are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
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Participants will be eligible to be included in the study only if all of the following criteria apply:
Age
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
Participants who are overtly medically healthy with clinically insignificant screening results (eg, laboratory profiles, medical histories, ECGs, physical examination) as assessed by the investigator, sub-investigator, or medical officer.
Weight
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 height in meters squared.
Sex and Contraceptive/Barrier Requirements
Contraceptive use by men and women should be consistent with local regulations regarding 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 of contraception (refer to inclusion criterion #5) when engaging in sexual activity from study check-in through 30 days following the last administration of the study drug, and to not donate sperm during this same period of time. If the sexual partner is surgically sterile, contraception is not necessary.
Female participants:
Females of childbearing potential must either be sexually abstinent for 14 days prior to Day 1 and agree to remain so through 30 days following the last administration of the study drug, OR have been using (or agree to use) 2 of the following acceptable methods of birth control for the times specified:
Informed Consent
Exclusion Criteria:
Participants will be excluded from the study if any of the following criteria apply:
Medical Conditions
Any other condition or prior therapy, which, in the opinion of the investigator, sub-investigator, or medical officer would make the participant unsuitable for this study.
Prior/Concomitant Therapy
Use of antacids, H2 receptor blockers or proton pump inhibitors 7 days prior to Day 1. This includes calcium carbonate.
Prior/Concurrent Clinical Study Experience
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
Any clinically significant abnormalities in laboratory values at screening or check-in (Day -1), in particular:
Other Exclusion Criteria
DDI crossover part of the study, subjects will be enrolled into 3 cohorts of 8 subjects each, Cohorts 1, 2, \& 3 respectively. All subjects in Cohorts 1, 2, and 3 will receive a single dose of xeruborbactam oral prodrug (XOP) on Day 1. On Day 6, they will receive a single dose of ceftibuten. On Day 9 they will receive a single combined dose of XOP and ceftibuten. During the MAD part of the study, subjects will be enrolled into 2 cohorts, Cohorts 4 \& 5 respectively. Subjects in Cohorts 4 (16 subjects) will receive either a combined dose of XOP and ceftibuten, active ceftibuten, or active XOP. Cohort 4 will be dosed BID on Days 1-9, with last dose on the morning of Day 10. Subjects in Cohort 5 (15 subjects) will receive active XOP in comb with active ceftibuten which will be admin orally either twice on Day 1 and QD on Days 2-10 (Group 1), BID on Days 1-9 and QD on Day 10 (Group 2), or TID on Days 1-9 and once on Day 10 (Group 3), based on group assignment.
Drug: Xeruborbactam Oral Prodrug · Drug: Ceftibuten
During Cohort 4, Xeruborbactam Oral Prodrug Placebo and Ceftibuten placebo will be used to maintain the blind. In Cohort 4, ten (10) subjects in each cohort will receive a combined dose of xeruborbactam oral prodrug and ceftibuten. Three (3) subjects in each cohort will receive active ceftibuten capsules with xeruborbactam oral prodrug placebo capsules. Three (3) subjects in each cohort will receive active xeruborbactam oral prodrug capsules with ceftibuten placebo capsules.
Drug: Xeruborbactam Oral Prodrug Placebo · Drug: Ceftibuten Placebo
Experimental
Also known as: QPX7831
Experimental
Placebo Comparator
Also known as: QPX7831 Placebo
Placebo Comparator
Incidence of Treatment -Emergent Adverse events by subject and by cohort (single dose, multiple doses)
Number of patients with Treatment-Emergent Adverse Events by subject, by cohort, severity and relationship to treatment
Time frame: 16 days
Number of patients with changes from baseline in safety parameters
Number of patients with changes in safety parameters before and after dosing by subject and cohort
Time frame: 16 days
Peak plasma Concentration measurements by subject and by cohort (Cmax)
Comparison will be performed between the cohorts for concentration measurements (Cmax). Mean graphical presentation of the data will be reported. Statistical analysis of exposure parameters will be performed.
Time frame: 16 days
Time concentration data measurements by subject and by cohort (Tmax)
Comparison will be performed between the cohorts for time concentration data measurements (Tmax)
Time frame: 16 days
Area under the plasma concentration versus time curve (AUC) between cohorts
Comparison will be performed between the cohorts for area under the plasma concentration versus time curve (AUC). Mean graphical presentation of the data will be reported. Statistical analysis of exposure parameters will be performed.
Time frame: 16 days
Urine Pharmacokinetic (PK) amount excreted by subject and by cohort
Urine Pharmacokinetic (PK) parameters such as amount excreted will be calculated from urinary excretion data
Time frame: 16 days
Urine Pharmacokinetic (PK) % dose excreted by subject and by cohort
Urine Pharmacokinetic (PK) parameters such as amount of % dose excreted will be calculated from urinary excretion data
Time frame: 16 days
Plan to share: No
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Qpex Biopharma, Inc.