Recruiting
Phase 2

Aztreonam & Avibactam

Sponsor:

Pfizer

Code:

NCT05639647

Conditions

Gram-negative Bacterial Infections

Eligibility Criteria

Sex: All

Age: 0 - 17

Healthy Volunteers: Not accepted

Interventions

ATM-AVI

BAT

Study Details

Brief summary:

The purpose of this study is to evaluate how Aztreonam (ATM) and Avibactam (AVI) are processed in pediatric participants. This study also aims to understand participant safety and effects in pediatric participants.

The study is seeking participants who are:

  • 9 months to less than 18 years of age
  • Hospitalized
  • Suspected/known to have a gram-negative infection
  • Receiving intravenous (iv, given directly into a vein) antibiotics
  • Being treated for complicated infections of various body parts that includes the abdomen, urinary tract, blood stream, and lungs.
  • Participants will receive either ATM-AVI or best available therapy (BAT).
  • Both therapies will be given through a vein.
  • Participants with complicated abdominal infections will also receive iv Metronidazole (MTZ). Patients with cIAI and Cockayne Syndrome are excluded due to a risk of severe hepatotoxicity with the use of MTZ. - Participants on ATM-AVI treatment who have anaerobic infections will also receive iv MTZ at the study doctor's discretion.
  • The iv dose of ATM-AVI will be based on the participant's weight and kidney function.
  • The study doctor will determine the iv dose of BAT.
  • During the first 2 study days, participants on ATM-AVI therapy will have 5 blood draws in small quantities.
  • Starting on day 4, the study doctor will decide if participants may be switched to oral therapy.
  • Participants will receive a maximum of 14 days of ATM-AVI treatment.
  • After discharge from the hospital, 1 study visit may be required.
  • Depending on the participant's response, the study duration will be from 33 to 50 days.
  • The investigator will contact participants by phone 28 to 35 days after the last study treatment to check participants health status.

Conditions

Gram-negative Bacterial Infections

Study ID

NCT05639647

Start date

Apr 18, 2023

Status verified date

Jun, 2026

Completion date

Mar 31, 2027

Anticipated

Primary completion date

Mar 31, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 0 - 17

Healthy Volunteers: Not accepted

Inclusion Criteria

Participants must meet the following key inclusion criteria to be eligible for enrollment into the study:

1. Participants ≥9 months to <18 years of age at Screening; Female (post-menarchal) participants must have a negative serum/urine pregnancy test (β hCG sensitivity ≥25 mIU/mL).
2. Suspected/confirmed cIAI, cUTI, HAP/VAP, or BSI with gram-negative pathogens.
3. Require hospitalization and IV antibiotic treatment.

Exclusion Criteria

Participants with any of the following characteristics/conditions will be excluded:

1. Other medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
2. Gram-negative species not expected to respond to ATM AVI ≤14 days.
3. Pregnant or breastfeeding; fertile male/female unwilling/unable to use effective contraception for at ≥7 days (males) or ≥28 days (females) after last ATM-AVI infusion.

(HAP/VAP only):
4. Microbiologically known or high likelihood of monomicrobial infection with a gram-positive organism, lung abscess, pleural empyema, or post-obstructive pneumonia, lung or heart transplant.
5. Received >24 hours of systemic antibiotics during the 48 hours before randomization unless participant has documented treatment failure after at least 48 hours of antibiotic therapy.
6. Current use of any prohibited concomitant medication(s) or unwilling/unable (Cockayne Syndrome patients with cIAI are excluded) to use MTZ or having received previous investigational drug(s) or vaccine ≤30 days or 5 half-lives before randomization (whichever is longer).
7. CrCL ≤15 mL/min/1.73 m2 (eCrCl or eGFR calculation based on age).
8. Non-infectious related screening ALT or AST >3 x ULN, ALP >3 x ULN and/or TBili >2 x ULN (> 3 x ULN for Gilbert's syndrome).
9. Investigator site staff directly involved in the conduct of the study and their family members, site staff otherwise supervised by the investigator, and sponsor and sponsor delegate employees directly involved in the conduct of the study and their family members.

Study Design

Enrollment

48 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: ATM-AVI

ATM-AVI administered iv every 6 or 8 hours and dosed according to participant's weight and kidney function for up to 14 days depending on response. At the investigator's discretion, the participant may be switched to oral therapy after 3 days of iv ATM-AVI therapy

active comparator: Best available therapy (BAT)

BAT will be selected by the investigator and administered iv. At the investigator's discretion, the participant may be switched to oral therapy after 3 days of iv BAT

Interventions

ATM-AVI

A drug specifically designed to treat resistant gam-negative bacterial infections

BAT

BAT will be selected by the investigator and administered iv as appropriate for the selected drug(s)

Primary outcome measure

  • Maximum Predicted Plasma Concentration (Cmax) of ATM and AVI [ Time Frame: Up to 15 Days ]
  • Minimum Predicted Trough Plasma Concentration (Cmin) of ATM and AVI [ Time Frame: Up to 15 Days ]
  • Area under the Concentration-Time Curve (AUC) of ATM-AVI [ Time Frame: Up to 15 Days ]
  • Plasma Decay Half-Life (t1/2) [ Time Frame: Up to 15 Days ]
  • Apparent Clearance (CL) [ Time Frame: Up to 15 Days ]
  • Proportion of Participants reporting Adverse Events (AE) [ Time Frame: Baseline up to Day 50 ]
  • Proportion of Participants reporting Serious Adverse Events (SAE) [ Time Frame: Baseline up to Day 50 ]
  • Proportion of Participants reporting AEs leading to discontinuation [ Time Frame: Baseline up to Day 50 ]
  • Proportion of Participants reporting AEs resulting in death [ Time Frame: Baseline up to Day 50 ]
  • Proportion of Participants reporting liver injury and acute kidney injury of ATM-AVI relative to Best Available Therapy (BAT) [ Time Frame: Baseline up to Day 50 ]

Central Contacts and Locations

Central contacts

Pfizer CT.gov Call Center

1-800-718-1021ClinicalTrials.gov_Inquiries@pfizer.com

Locations

Rady Children's Hospital

Recruiting

San Diego, California, United States, 92123

Weill Cornell Medicine-New York Presbyterian Hospital

Recruiting

New York, New York, United States, 10021

Icahn School of Medicine at Mount Sinai

Recruiting

New York, New York, United States, 10029

More Information

Sponsor

Pfizer

Last update posted

Jul 1, 2026

Last verified

Jun, 2026

Keywords

  • Gram-negative bacterial infections

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Pfizer on 2026-07-01.