Carbapenem-Sparing Therapy for ESBL Bacteremia: New Trials, Old Questions

Author(s)Ryan K. Shields, PharmD, MS, Jason M. Pogue, PharmD, BCPS, BCIDP

New data from the PETERPEN trial suggest that piperacillintazobactam may be noninferior to meropenem for early clinical outcomes in select patients with ESBL bloodstream infections, but carbapenems remain the standard of care until final mortality results are available and fully analyzed.

For nearly a decade, the landmark MERINO randomized controlled trial (RCT; NCT02176122) has shaped how clinicians treat bloodstream infections caused by ceftriaxone-resistant Escherichia coli and Klebsiella pneumoniae. Its main message was clear and practice-changing: For all-cause 30-day mortality, piperacillin-tazobactam did not achieve noninferiority compared with meropenem.¹Among randomly assigned patients included in the primary analysis, death occurred in 12.3% (23 of 187) of those assigned to piperacillintazobactam compared with 3.7% (7 of 191) of those assigned to meropenem.

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