Adverse events associated with meropenem versus imipenem/cilastatin therapy in a large retrospective cohort of hospitalized infants

The Pediatric Infectious Disease Journal • July 2013

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Hornik CP, Herring AH, Benjamin DK Jr, Capparelli EV, Kearns GL, van den Anker J, Cohen-Wolkowiez M, Clark RH, Smith PB; Best Pharmaceuticals for Children Act-Pediatric Trials Network.

Carbapenems are commonly used in hospitalized infants despite a lack of complete safety data and associations with seizures in older children. We compared the incidence of adverse events in hospitalized infants receiving meropenem versus imipenem/cilastatin. We conducted a retrospective cohort study of 5566 infants treated with meropenem or imipenem/cilastatin in neonatal intensive care units managed by the Pediatrix Medical Group between 1997 and 2010.

Determining population and developmental pharmacokinetics of metronidazole using plasma and dried blood spot samples from premature infants

The Pediatric Infectious Disease Journal • July 2013

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Cohen-Wolkowiez M, Sampson M, Bloom BT, Arrieta A, Wynn JL, Martz K, Harper B, Kearns GL, Capparelli EV, Siegel D, Benjamin DK Jr, Smith PB; Best Pharmaceuticals for Children Act–Pediatric Trials Network.

Limited pharmacokinetic (PK) data of metronidazole in premature infants have led to various dosing recommendations. Surrogate efficacy targets for metronidazole are ill-defined and therefore aimed to exceed minimum inhibitory concentration of organisms responsible for intra-abdominal infections. We evaluated the PK of metronidazole using plasma and dried blood spot samples from infants ≤32 weeks gestational age in an open-label, PK, multicenter (N = 3) study using population PK modeling (NONMEM).

Pharmacokinetics of Moxifloxacin in an Infant with Mycoplasma hominis Meningitis

The Pediatric Infectious Disease Journal February 2013

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Watt KM, Massaro MM, Smith B, Cohen-Wolkowiez M, Benjamin DK Jr, Laughon MM
Treatment of Mycoplasma hominis meningitis in infants is limited by a lack of consensus regarding therapy and limited pharmacokinetic data for agents to which M. hominis is susceptible. We report the successful treatment of a premature infant with M. hominis meningitis with doxycycline and moxifloxacin and provide a pharmacokinetic profile of moxifloxacin.

Safety and effectiveness of meropenem in infants with suspected or complicated intra-abdominal infections

Clinical Infectious Disease • December 2012

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Cohen-Wolkowiez M, Poindexter B, Bidegain M, Weitkamp JH, Schelonka RL, Randolph DA, Ward RM, Wade K, Valencia G, Burchfield D, Arrieta A, Mehta V, Walsh M, Kantak A, Rasmussen M, Sullivan JE, Finer N, Rich W, Brozanski BS, van den Anker J, Blumer J, Laughon M, Watt KM, Kearns GL, Capparelli EV, Martz K, Berezny K, Benjamin DK Jr, Smith PB; Meropenem Study Team.

Intra-abdominal infections are common in young infants and lead to significant morbidity and mortality. Meropenem is a broad-spectrum antimicrobial with excellent activity against pathogens associated with intra-abdominal infections. The purpose of this study was to determine the safety and effectiveness of meropenem in young infants with suspected or complicated intra-abdominal infections.

five kids laying in the grass.

DCRI researchers complete first drug study for Pediatric Trials Network

DCRI investigators have completed the study of metronidazole, an anti-microbial agent frequently administered to infants suffering from necrotizing enterocolitis.

The Duke Clinical Research Institute has completed its first drug trial conducted for the Pediatric Trials Network (PTN).

Late last year (2011), DCRI investigators completed their study of metronidazole, an anti-microbial agent frequently administered to infants suffering from necrotizing enterocolitis (NEC). The disease, which causes the victim’s intestinal lining to die, occurs frequently in premature infants and is often fatal.

Doctors have long prescribed metronidazole to infants suffering from NEC, even though there was no reliable information about dosage amounts for children. Metronidazole was not unique in that regard. Prescription medicines are rarely packaged with information about appropriate doses for children. That began to change in 2002, when Congress passed the Best Pharmaceuticals for Children Act (BPCA), a law designed to promote pediatric drug research. The PTN, an alliance of clinical research institutions working in concert with the Eunice Kennedy Shriver National Institute of Child Health and Human Development, was established shortly thereafter. Its goal is to provide doctors with pediatric dosing guidelines for widely prescribed medicines lacking that information. In September 2010, the National Institutes of Health awarded a $95 million contract to the DCRI’s Daniel Benjamin, MD, MPH, PhD, to oversee the first round of clinical trials under the PTN to determine appropriate dosing regimens for children. The metronidazole study began enrollment in January 2011.

The metronidazole study team, pictured above: Mickey Cohen-Wolkowiez, Jennifer Murphy, Debbe Blackwell, Barrie Harper, Ivra Bunn
The metronidazole study team, pictured above: Mickey Cohen-Wolkowiez, Jennifer Murphy, Debbe Blackwell, Barrie Harper, Ivra Bunn

The purpose of the metronidazole study was to determine the pharmacokinetics and safety of the drug in young children, and thereby determine an appropriate dosing regimen. The metronidazole trial was the first one to enroll patients and complete its study under the PTN contract. The DCRI’s Michael Cohen-Wolkowiez, MD, served as principal investigator. Barrie Harper, MT, was project leader.

The trial, which was conducted at three study centers, enrolled 24 premature infants with suspected infections. Researchers divided the infants into two groups based on their age. One group comprised infants younger than 14 days, the other included infants 14 days or older. Both groups received an equal dose of metronidazole at age-based frequencies over a period of several days. Researchers took blood samples from the infants during the trial to determine how the drug levels behaved within the infants’ bodies.

After analyzing the data, researchers intend to present their findings to the Food and Drug Administration. They hope to submit new dosing guidelines for metronidazole in infants to agency officials to update the metronidazole package insert.

“The goal of the entire PTN is to potentially modify the package inserts with meaningful dosing information for children, which doesn’t exist yet,” Harper said. “Children aren’t little adults, even though a lot of physicians dose them like little adults.”

Harper and Cohen-Wolkowiez agreed that the PTN aided the speed and efficiency of the metronidazole study. The improved communication and collaboration engendered by the network allows researchers to complete their studies on time and on budget, Harper said. The metronidazole study was finished within 18 months.

“We thought we would need a 12-month period [for enrollment],” Harper said. “We beat that.”

“The time line under which this study was completed was exceptional, and it was reached thanks to the professionalism and dedication of the DCRI team,” Cohen-Wolkowiez said. “This study will become a major player in the renewal of BPCA in 2012.”

Harper also credited the DCRI team and its partners at the Emmes Corporation, the NICHD’s data coordinating center, for the study’s success.

“Our people worked really hard on this project, and they were really excited about it,” she said. “It’s been a very collaborative effort.”

Population pharmacokinetics of meropenem in plasma and cerebrospinal fluid of infants with suspected or complicated intra-abdominal infections

The Pediatric Infectious Disease Journal • October 2011

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Smith PB, Cohen-Wolkowiez M, Castro LM, Poindexter B, Bidegain M, Weitkamp JH, Schelonka RL, Ward RM, Wade K, Valencia G, Burchfield D, Arrieta A, Bhatt-Mehta V, Walsh M, Kantak A, Rasmussen M, Sullivan JE, Finer N, Brozanski BS, Sanchez P, van den Anker J, Blumer J, Kearns GL, Capparelli EV, Anand R, Benjamin DK Jr; Meropenem Study Team.

Suspected or complicated intra-abdominal infections are common in young infants and lead to significant morbidity and mortality. Meropenem is a broad-spectrum antimicrobial agent with excellent activity against pathogens associated with intra-abdominal infections in this population. The purpose of this study was to determine the pharmacokinetics (PK) of meropenem in young infants as a basis for optimizing dosing and minimizing adverse events.

Innovative clinical trial design for pediatric therapeutics

Expert Review of Clinical Pharmacology • September 2011

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Laughon MM, Benjamin DK Jr, Capparelli EV, Kearns GL, Berezny K, Paul IM, Wade K, Barrett J, Smith PB, Cohen-Wolkowiez M.

Until approximately 15 years ago, sponsors rarely included children in the development of therapeutics. US and European legislation has resulted in an increase in the number of pediatric trials and specific label changes and dosing recommendations, although infants remain an understudied group.