Ampicillin dosing in premature infants for early-onset sepsis: exposure-driven efficacy, safety, and stewardship

Journal of Perinatology July 2022

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Le J, Greenberg RG, Yoo Y, Clark RH, Benjamin DK Jr., Zimmerman KO, Cohen-Wolkowiez M, Wade K
This study simulated ampicillin concentrations in newborns to define optimal ampicillin dosing for empiric early-onset sepsis (EOS) therapy in preterm neonates. For EOS in preterm infants, two ampicillin doses (50 mg/kg) provided optimal bactericidal exposures, while minimizing potential toxicity.

Prolonged Post-Discontinuation Antibiotic Exposure in Very Low Birth Weight Neonates at Risk for Early-Onset Sepsis

Journal of the Pediatric Infectious Diseases Society May 2021

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Le J, Greenberg RG, Benjamin DK Jr, Yoo Y, Zimmerman KO, Cohen-Wolkowiez M, Wade KC; on behalf of the Administrative Core Committee of the Best Pharmaceuticals for Children Act – Pediatric Trials Network
Premature, very low birth weight neonates are at risk for early-onset sepsis and receive ampicillin and gentamicin post-birth. Antimicrobial stewardship supports short-course antibiotics, but how long antibiotic concentrations remain therapeutic post-last dose is unknown. This study used simulations to examine antibiotic exposures in 34,689 neonates. Therapeutic exposure for ampicillin and gentamicin was evaluated relative to the minimum inhibitory concentration for common pathogens. Ampicillin exposure remains therapeutic long after the last dose. Short-course ampicillin provided therapeutic exposures throughout the typical blood culture incubation period.

Medication Use in the Neonatal Intensive Care Unit and Changes from 2010 to 2018

The Journal of Pediatrics January 2022

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Stark A, Smith PB, Hornik CP, Zimmerman KO, Hornik CD, Pradeep S, Clark RH, Benjamin DK, Laughon M, Greenberg RG.

The goal of this study was to provide up-to-date medication prescribing patterns in US neonatal intensive care units (NICUs) and to examine trends in prescribing patterns over time. The most frequently prescribed medications included ampicillin, gentamicin, caffeine citrate, poractant alfa, morphine, vancomycin, furosemide, fentanyl, midazolam, and acetaminophen. Of the top 50 medications used in infants with extremely low birth weight, only 20 (40%) are FDA-labeled for use in infants. Trends of medication use in the NICU change substantially over time. It is imperative to identify changes in medication use in the NICU to better inform further prospective studies.

Antibiotic Safety and Effectiveness in Premature Infants With Complicated Intraabdominal Infections

The Pediatric Infectious Disease Journal June 2021

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Smith MJ, Boutzoukas A, Autmizguine J, Hudak M, Zinkhan E, Bloom BT, Heresi G, Lavery A, Courtney S, Sokol GR, Cotton CM, Bliss J, Mendley S, Bendel C, Dammann C, Weitkamp JH, Saxonhouse MA, Mundakel GT, Debski J, Lewandowski A, Erinjeri J, Gao J, Benjamin DK, Hornik C, Smith PB, Cohen-Wolkowiez M, on behalf of the Best Pharmaceuticals for Children Act – Pediatric Trials Network
In premature infants, complicated intraabdominal infections (cIAIs) are a leading cause of morbidity and mortality. Although universally prescribed, the safety and effectiveness of commonly used antibiotic regimens have not been established in this population. One hundred eighty infants ≤33 weeks gestational age and <121 days postnatal age with cIAI were randomized to ≤10 days of ampicillin, gentamicin, and metronidazole (group 1); ampicillin, gentamicin, and clindamycin (group 2); or piperacillin-tazobactam and gentamicin (group 3). There were no differences in safety outcomes between antibiotic regimens. Each of the antibiotic regimens are safe in premature infants with cIAI.

Comparative Analysis of Ampicillin Plasma and Dried Blood Spot Pharmacokinetics in Neonates

Therapeutic Drug Monitoring • February 2018

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Le J, Poindexter B, Sullivan JE, Laughon M, Delmore P, Blackford M, Yogev R, James LP, Melloni C, Harper B, Mitchell J, Benjamin DK Jr, Boakye-Agyeman F, Cohen-Wolkowiez M.

Dried blood spot (DBS) is a practical sampling strategy for pharmacokinetic studies in neonates. The utility of DBS to determine the population pharmacokinetics (pop-PK) of ampicillin, as well as accuracy versus plasma samples, was evaluated. An open-label, multicenter, opportunistic, prospective study was conducted in neonates.

Electronic Health Records and Pharmacokinetic Modeling to Assess the Relationship between Ampicillin Exposure and Seizure Risk in Neonates

Journal of Pediatrics • August 2016

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Hornik CP, Benjamin DK Jr, Smith PB, Pencina MJ, Tremoulet AH, Capparelli EV, Ericson JE, Clark RH, Cohen-Wolkowiez M; Best Pharmaceuticals for Children Act—Pediatric Trials Network.

This was a retrospective observational cohort study of electronic health record (EHR) data combined with pharmacokinetic model derived drug exposure predictions. We used the EHR from 348 Pediatrix Medical Group neonatal intensive care units from 1997 to 2012. We included all infants 24-41 weeks gestational age, 500-5400 g birth weight, first exposed to ampicillin prior to 25 days postnatal age. In this cohort of hospitalized infants, higher ampicillin exposure was associated with seizures as documented in the EHR.

Characterization of the population pharmacokinetics of ampicillin in neonates using an opportunistic study design

Antimicrobial Agents and Chemotherapy • June 2014

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Tremoulet A, Le J, Poindexter B, Sullivan JE, Laughon M, Delmore P, Salgado A, Ian-U Chong S, Melloni C, Gao J, Benjamin DK Jr, Capparelli EV, Cohen-Wolkowiez M; Administrative Core Committee of the Best Pharmaceuticals for Children Act-Pediatric Trials Network.

Although ampicillin is the most commonly used drug in neonates, developmental pharmacokinetic (PK) data to guide dosing are lacking. Ampicillin is primarily renally eliminated, and developmental changes are expected to influence PK. We conducted an open-label, multicenter, opportunistic, prospective PK study of ampicillin in neonates stratified by gestational age (GA) (≤ 34 or >34 weeks) and postnatal age (PNA) (≤ 7 or >7 days).