A Study to Assess Sulbactam-durlobactam in Pediatric Patients With Acinetobacter Baumannii-calcoaceticus Complex Infection

A Multicenter, Open-label, Phase 1b Study to Assess the Pharmacokinetics, Safety, and Tolerability of Sulbactam-Durlobactam in Hospitalized Pediatric Patients From Birth to <18 Years Who Are Receiving Systemic Antibiotic Therapy for Suspected or Confirmed Acinetobacter Baumannii-calcoaceticus Complex Infection

The goal of this clinical trial is to investigate the use of Sulbactam-Durlobactam (SUL-DUR) in pediatric patients and is being conducted to collect pharmacokinetic (PK) and safety data to enable the identification of appropriate pediatric dosing regimens for patients with Acinetobacter baumannii-calcoaceticus complex (ABC) infections

Study Overview

• Status: Recruiting
• Conditions: Acinetobacter Baumannii-calcoaceticus Complex Infection (ABC)
• Intervention / Treatment: Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 6 hours); Drug: Sulbactam 20mg/kg-Durlobactam 20mg/kg (Every 8 hours); Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 8 hours); Drug: Sulbactam 20mg/kg-Durlobactam 20mg/kg (Every 12 hours)

• Study Type: Interventional
• Enrollment (Estimated): 48
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: ISTX Clinical Trials; Phone Number: 617-715-3600; Email: clinicaltrials@istx.com

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90095
      • Recruiting
      • UCLA Medical Center
    • San Diego, California, United States, 92123
      • Recruiting
      • Rady Children's Hospital
  • North Carolina
    • Greenville, North Carolina, United States, 27834
      • Recruiting
      • ECU Brody School of Medicine
  • Texas
    • Galveston, Texas, United States, 77555-5302
      • Recruiting
      • University Of Texas Medical Branch At Galveston

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patient from birth (defined as post-natal age of 7 days) to <18 years of age at the time of written informed consent (and assent, if applicable) and is hospitalized.
2. Patient and/or parent(s) or legal guardian(s) have provided the written informed consent and/or assent.
3. Patient has confirmed or suspected diagnosis of ABC infection and requires IV antibiotics for treatment.
4. Patient has expected survival of 30 days after enrollment in the study.
5. If patient is an individual of childbearing potential or reproductive potential, then the patient must remain abstinent OR must utilize one of the highly effective methods of contraception (ie, condom, combined oral contraceptive, implant, or injectable) from at least 30 days prior to screening until at least 30 days after administration of the last dose of study drug.

Exclusion Criteria:

1. Patient is a preterm infant, born at <28 weeks gestational age.
2. Patient has history of significant hypersensitivity or allergic reaction to any β-lactam, any contraindication to the excipients used in the formulation, or any contraindication to the use of β-lactam antibiotics. Note: For β-lactams, a history of a mild rash followed by uneventful re-exposure is not a contraindication to enrollment.
3. Patient is in refractory septic shock at the time of enrollment, defined as persistent hypotension despite adequate fluid resuscitation or vasopressive therapy.
4. Patient is pregnant, breastfeeding, or intends to become pregnant.
5. Patient is receiving peritoneal dialysis or cardiopulmonary bypass.
6. Patient has received blood transfusion within 24 hours of study drug administration.
7. Patient is a newborn with clinically significant anemia who, in the opinion of the investigator, will not be able to tolerate the necessary blood draws to complete the study activities.
8. Patient (or patient's mother, if the patient is being breastfed) is using or will need to use any medications known to inhibit organic anion transporter 1 (OAT1) (eg, probenecid).
9. Patient has clinically significant renal, hepatic, or hemodynamic instability.
10. For Cohorts 1 through 3 only: patient has weight outside of the 5th to 95th percentile based on age.
11. Patient has an age-appropriate estimated creatinine clearance that indicates renal impairment.

12. Patient has the following laboratory results at Screening:

    1. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) >3×upper limit of normal (ULN) and,
    2. Total bilirubin >2×ULN for age with conjugated/direct bilirubin >20% of the total. Note: Patients with AST or ALT up to 5×ULN are eligible if these elevations are acute and are documented as being directly related to the infectious process being treated.
13. Patient has clinically significant abnormal laboratory test results not related to the underlying infection that might expose the patient to risk by participating in the trial, confound the results of the trial, or interfere with the patient's participation for the full duration of the trial.
14. Patient (or patient's mother, if the patient is being breastfed) has participated in a clinical study involving investigational medication or an investigational device within the last 30 days or 5 half-lives, whichever is longer, prior to first dose of the study drug.
15. Patient has any condition that, in the opinion of the investigator, would compromise the safety of the patient or the quality of the data.
16. Patient is unable or unwilling, in the opinion of the investigator, to comply with the protocol.
17. Patient (or patient's mother, if the patient is being breastfed) has previously received durlobactam.
18. Patient (or patient's mother, if the patient is being breastfed) has received sulbactam and/or sulbactam-containing regimens (eg, Unasyn) within 72 hours of first dose of the study drug.
19. Patient (or patient's mother, if the patient is being breastfed) has received amphotericin B within 7 days of first dose of the study drug.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cohort 3; Pediatric patients 1 year to <6 years of age	Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 6 hours); 25mg/kg SUL and 25mg/kg DUR; Other Names: SUL-DUR
Experimental: Cohort 4; Pediatric patients 3 months to <1 year of age	Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 6 hours); 25mg/kg SUL and 25mg/kg DUR; Other Names: SUL-DUR
Experimental: Cohort 5 Subgroup 1; Aged 2 months to <3 months, term and preterm (gestational age >28 weeks) Term infants will receive 25mg/kg SUL and 25mg/kg DUR Preterm infants will receive 20mg/kg SUL and 20mg/kg DUR	Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 6 hours); 25mg/kg SUL and 25mg/kg DUR; Other Names: SUL-DUR; Drug: Sulbactam 20mg/kg-Durlobactam 20mg/kg (Every 8 hours); 20mg/kg SUL and 20mg/kg DUR; Other Names: SUL-DUR
Experimental: Cohort 5 Subgroup 2; Aged birth to <2 months, term and preterm (gestational age >28 weeks and post-natal age >7 days) Term infants will receive 25mg/kg SUL and 25mg/kg DUR Preterm infants will receive 20mg/kg SUL and 20mg/kg DUR	Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 8 hours); 25mg/kg SUL and 25mg/kg DUR; Other Names: SUL-DUR; Drug: Sulbactam 20mg/kg-Durlobactam 20mg/kg (Every 12 hours); 20mg/kg SUL and 20mg/kg DUR; Other Names: SUL-DUR
Experimental: Cohort 1; Pediatric patients 12 years to <18 years of age Sulbactam 25mg/kg -Durlobactam 25mg/kg, not to exceed 1g sulbactam - 1g durlobactam (Every 6 hours)	Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 6 hours); 25mg/kg SUL and 25mg/kg DUR; Other Names: SUL-DUR
Experimental: Cohort 2; Pediatric patients 6 years to <12 years of age Sulbactam 25mg/kg -Durlobactam 25mg/kg, not to exceed 1g sulbactam - 1g durlobactam (Every 6 hours)	Drug: Sulbactam 25mg/kg -Durlobactam 25mg/kg (Every 6 hours); 25mg/kg SUL and 25mg/kg DUR; Other Names: SUL-DUR

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Assess the pharmacokinetic (PK) parameters for maximum concentration (Cmax) of sulbactam and durlobactam	Day 1 and Day 3
Assess the PK parameters for area under the plasma concentration-time curve from 0 to 24 hours (AUC 0-24) of sulbactam and durlobactam	Day 1 and Day 3

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of serious TEAEs		28 days
Percentage of participants experiencing Treatment Emergent Adverse Events (TEAEs)	Defined as any adverse event occurring after exposure to the study drug or any AE that worsens in intensity or frequency	28 days
Percentage of TEAEs leading to study drug discontinuation		28 days
Incidence of related TEAEs		28 days
Change from baseline values of liver function measured by Comprehensive Metabolic Panel (CMP)		Baseline and Day 28
Change from baseline values of kidney function measured by CMP		Baseline and Day 28
Change from baseline values of hemoglobin		Baseline and Day 28
Change from baseline value of white blood cell count		Baseline and Day 28
Change from baseline value of platelets		Baseline and Day 28
Change from baseline value of diastolic blood pressure		Baseline and Day 28
Change from baseline value of systolic blood pressure		Baseline and Day 28
Change from baseline values of heart rate		Baseline and Day 28
Change from baseline value of respiration rate		Baseline through Day 28
Change from baseline value of temperature		Baseline and Day 28

Collaborators and Investigators

• Sponsor: Innoviva Specialty Therapeutics
• Collaborators: Entasis Therapeutics

Study record dates

Study Major Dates

• Study Start (Estimated): October 30, 2026
• Primary Completion (Estimated): May 5, 2028
• Study Completion (Estimated): May 20, 2028

Study Registration Dates

• First Submitted: January 16, 2025
• First Submitted That Met QC Criteria: January 22, 2025
• First Posted (Actual): January 30, 2025

Study Record Updates

• Last Update Posted (Actual): March 3, 2026
• Last Update Submitted That Met QC Criteria: February 27, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Acinetobacter; ABC infection; Acinetobacter baumannii-calcoaceticus complex infection; Ventilator-associated bacterial pneumonia; Sulbactam-durlobactam; Hospital-acquired bacteria pneumonia
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Infections; Communicable Diseases; Sulfur Compounds; Organic Chemicals; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Amides; beta-Lactams; Lactams; Penicillins; Sulbactam; durlobactam
• Other Study ID Numbers: CS2514-2023-002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Time Frame: Data requests may be submitted starting 6 months after primary article publication and the data will be made accessible for up to 24 months; extensions may be considered on a case-by-case basis. Access criteria: Subject to certain criteria, conditions, and exceptions and upon completion of the review
• IPD Sharing Access Criteria: Subject to certain criteria, conditions, and exceptions and upon completion of the review and approval of the Research Proposal and Statistical Analysis Plan, Qualified Researchers engaging in independent scientific research can be provided de-identified IPD following the execution of a Data Sharing Agreement
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No