Comparing two antibiotics for treating bloodstream infections from resistant bacteria

Piperacillin Tazobactam Versus Meropenem for Treatment of Bloodstream Infections Caused by Cephalosporin-resistant Enterobacteriaceae- a Non-inferiority Randomized Controlled Trial

Phase 4 Interventional Rambam Health Care Campus · NCT03671967

This study is testing if a new antibiotic called piperacillin-tazobactam works as well as meropenem for treating bloodstream infections caused by resistant bacteria in adults.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment1084 (estimated)
Ages18 Years and up
SexAll
SponsorRambam Health Care Campus Academic / other
Locations14 sites (Calgary, Alberta and 13 other locations)
Trial IDNCT03671967 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the effectiveness of piperacillin-tazobactam compared to meropenem in treating bloodstream infections caused by cephalosporin-resistant Enterobacteriaceae. The study focuses on adult patients with new onset bacteremia due to E. coli or Klebsiella spp. and aims to determine if piperacillin-tazobactam is as effective as meropenem. Participants will be monitored for treatment outcomes to assess the non-inferiority of piperacillin-tazobactam. The trial includes both community and hospital-acquired infections.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with bloodstream infections caused by E. coli or Klebsiella spp. that are resistant to third-generation cephalosporins.

Not a fit: Patients with polymicrobial bacteremia or those who have had more than 72 hours since their initial blood culture may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide an effective alternative treatment option for patients with resistant bacterial infections.

How similar studies have performed: Other studies have shown mixed results when comparing similar antibiotic treatments, making this approach both relevant and necessary.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Adults (age ≥ 18 years)
2. New onset BSI due to E. coli or Klebsiella spp. in one or more blood cultures associated with evidence of infection.
3. The microorganism will have to be non-susceptible to third generation cephalosporins (ceftriaxone and ceftazidime) and susceptible to both PTZ and meropenem (see microbiological methods).
4. Both community and hospital-acquired bacteremias will be included.
5. We will permit the inclusion of bacteremias due to E. coli or Klebsiella spp. with concomitant growth in blood of skin commensals considered as contaminants.

Exclusion Criteria:

1. More than 72 hr. elapsed since initial blood culture taken, regardless of the time covering antibiotics were started (up to 72 hrs.).
2. Polymicrobial bacteremia. Polymicrobial bacteremia will be defined as either growth of two or more different species of microorganisms in the same blood culture, or growth of different species in two or more separate blood cultures within the same episode.
3. Patients with prior bacteremia or infection that have not completed antimicrobial therapy for the previous infectious episode.
4. Patients with septic shock at the time of enrollment and randomization, defined as at least 2 measurements of systolic blood pressure \< 90 mmHg and/or use of vasopressors (dopamine\>15μg/kg/min, adrenalin\>0.1μg/kg/min, noradrenalin\>0.1μg/kg/min, vasopressin any dose) in the 12 hours prior to randomization. In the absence of the use of vasopressors, a systolic blood pressure \<90 would need to represent a deviation for the patient's known normal blood pressure.
5. BSI due to specific infections known at the time of randomization:

   1. Endocarditis / endovascular infections
   2. Osteomyelitis (not resected)
   3. Central nervous system infections
6. Allergy to any of the study drugs confirmed by history taken by the investigator
7. Previous enrollment in this trial
8. Concurrent participation in another interventional clinical trial
9. Imminent death (researcher's assessment of expected death within 48 hrs. of recruitment)

Where this trial is running

Calgary, Alberta and 13 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Beta Lactam Resistant Bacterial InfectionEnterobacteriaceae InfectionsBacteremiabacteremiaenterobacteriaceaeextended spectrum beta-lactamasemeropenempiperacillin tazobactam
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.