Dosing recommendations

Application of Physiologically Based Pharmacokinetic Modeling to Characterize the Effects of Age and Obesity on the Disposition of Levetiracetam in the Pediatric Population

Posted on by Kayla Korzekwinski

Clinical Pharmacokinetics • June 2024

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Maglalang PD, Sinha J, Zimmerman K, McCann S, Edginton A, Hornik CP, Hornik CD, Muller WJ, Al-Uzri A, Meyer M, Chen L, Anand R, Perrin E, Gonzalez D., Best Pharmaceuticals for Children Act–Pediatric Trials Network Steering Committee

Levetiracetam is an antiseizure medication used for several seizure types in adults and children aged 1 month and older; however, due to a lack of data, pharmacokinetic (PK) variability of levetiracetam is not adequately characterized in certain populations, particularly neonates, children younger than 2 years of age, and children older than 2 years of age with obesity. PBPK modeling simulations revealed that the current US FDA-labeled pediatric dosing regimen listed in the prescribing information can produce the required exposure of levetiracetam in these target populations with dose adjustments for children with obesity aged 4 years to younger than 16 years.

Late-Onset Sepsis Evaluation and Empiric Therapy in Extremely Low Gestational Age Newborns

Posted on by Kayla Korzekwinski

Journal of the Pediatric Infectious Diseases Society • December 2023

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Speier RL, Cotton CM, Lewis K, Benajmin DK Jr, Keeler K, Kidimbu G, Roberts W, Clark RH, Zimmerman KO, Stark A, Greenberg RG

Little is known about late-onset sepsis (LOS) evaluations in extremely low gestational age newborns (ELGANs). This study describes frequencies of LOS evaluation in ELGANs, infant characteristics, and empiric therapy choices during evaluations.

Pharmacokinetics and Proposed Dosing of Levetiracetam in Children With Obesity

Posted on by Kayla Korzekwinski

The Journal of Pediatric Pharmacology and Therapeutics • December 2023

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Zimmerman KO, Wu H, Maharaj A, Turner A, Chen L, Hornik CD, Arnold S, Muller W, Al-Uzri A, Meyer M, Shiloh-Malawsky Y, Taravath S, Lakhotia A, Joshi C, Jackman J, Hornik CP; on behalf of the Best Pharmaceuticals for Children Act – Pediatric Trials Network

This study sought to characterize levetiracetam pharmacokinetics (PK) in children with obesity to inform dosing. Weight-tiered dosing for levetiracetam oral solution and tablets for children with obesity 4 to <16 years old results in more comparable exposures to children of normal weight.

Safety of sildenafil in premature infants at risk of bronchopulmonary dysplasia: Rationale and methods of a phase II randomized trial

Posted on by Kayla Korzekwinski

Contemporary Clinical Trials Communications • December 2022

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Lang JE, Hornik CD, Martz K, Jacangelo J, Anand R, Greenberg R, Hornik C, Zimmerman K, Smith PB, Benjamin DK, Laughon M
Bronchopulmonary dysplasia (BPD) is a disease of chronic respiratory insufficiency stemming from premature birth and iatrogenic lung injury leading to many complications. BPD is the most common pulmonary sequela of prematurity and is often fatal; however, there remains no FDA-approved therapies to treat or prevent BPD. Sildenafil is increasingly used off-label in premature infants despite scant safety and efficacy data. We developed the phase II SIL02 trial to describe the safety, pharmacokinetics and preliminary effectiveness of intravenous and enteral sildenafil in premature infants at risk for BPD.

Use of Real-World Data and Physiologically-Based Pharmacokinetic Modeling to Characterize Enoxaparin Disposition in Children With Obesity

Posted on by Kayla Korzekwinski

Clinical Pharmacology & Therapeutics • August 2022

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Gerhart JG, Carreño FO, Loop MS, Lee CR, Edginton AN, Sinha J, Kumar KR, Kirkpatrick CM, Hornik CP, Gonzalez D; Best Pharmaceuticals for Children Act – Pediatric Trials Network Steering Committee
Dosing guidance for children with obesity is often unknown despite the fact that nearly 20% of US children are classified as obese. Enoxaparin, a commonly prescribed low-molecular-weight heparin, is dosed based on body weight irrespective of obesity status to achieve maximum concentration within a narrow therapeutic or prophylactic target range. However, whether children with and without obesity experience equivalent enoxaparin exposure remains unclear. The study aimed to answer this clinical question. Enoxaparin exposure was better matched across age groups and obesity status using fat-free mass weight-based dosing.

Exposure-safety relationship for acyclovir in the treatment of neonatal herpes simplex virus disease

Posted on by Kayla Korzekwinski

Early Human Development • July 2022

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Ericson J, Benjamin DK Jr., Boakye-Agyeman F, Balevic SJ, Cotten MC, Adler-Shohet F, Laughon M, Poindexter B, Harper B, Payne EH, Kaneshige K, Smith PB; Best Pharmaceuticals for Children Act – Pediatric Trials Network
Neonatal herpes simplex virus (HSV) disease has been treated with high-dose (20 mg/kg/dose) acyclovir since 1991. This study aimed to determine the safety of acyclovir in infants with neonatal HSV treated with high-dose acyclovir and examine the association between acyclovir dose and exposure with adverse events (AEs). The odds of experiencing any clinical or laboratory AE did not differ by predicted acyclovir exposure. Although AEs were common with high-dose acyclovir exposure, severe AEs were rare. Acyclovir exposure was not associated with AEs.

Population Pharmacokinetics of Piperacillin/Tazobactam Across the Adult Lifespan

Posted on by Kayla Korzekwinski

Clinical Pharmacokinetics • January 2023

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Hemmersbach-Miller M, Balevic SJ, Winokur PL, Landersdorfer C, Gu K, Chan AW, Cohen-Wolkowiez M, Conrad T, An G, Kirkpatrick C, Swamy GK, Walter EB, Schmader KE

Piperacillin/tazobactam is one of the most frequently used antimicrobials in older adults. Using an opportunistic study design, we evaluated the pharmacokinetics of piperacillin/tazobactam as a probe drug to evaluate changes in antibacterial drug exposure and dosing requirements, including in older adults.

Extrapolation of Adult Efficacy Data to Pediatric Systemic Lupus Erythematosus: Evaluating Similarities in Exposure-Response

Posted on by Kayla Korzekwinski

Journal of Clinical Pharmacology • January 2023

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Balevic SJ, Niu J, Chen J, Green D, McMahon A, Hornik CP, Schanberg L, Glaser R, Doddapaneni S, Gonzalez D, Burckart GJ

To streamline drug development, the United States Food and Drug Administration (FDA) can consider the extrapolation of adult efficacy data to children when the disease and drug effects are sufficiently similar. This study explored whether the relationship between drug exposure and response for selected drugs in systemic lupus erythematosus (SLE) was sufficiently similar to support a consideration of the extrapolation of adult efficacy data to children of ≥5 years of age.

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

Posted on by Kayla Korzekwinski

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.

Use of physiologically-based pharmacokinetic modeling to inform dosing of the opioid analgesics fentanyl and methadone in children with obesity

Posted on by Kayla Korzekwinski

CPT: Pharmacometrics & Systems Pharmacology • June 2022

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Gerhart JG, Carreno FO, Ford JL, Edginton AN, Perrin EM, Watt KM, Muller WJ, Atz AM, Al-Uzri A, Delmore P, Gonzalez D; on behalf of the Best Pharmaceuticals for Children Act – Pediatric Trials Network Steering Committee
Children with obesity are commonly prescribed the opioids fentanyl and methadone, and accurate dosing is critical to reducing the risk of serious adverse events associated with overexposure. However, there is limited information to guide fentanyl and methadone dosing in these children. This study addresses the clinical knowledge gap using physiologically-based pharmacokinetic models of fentanyl and methadone developed in adults and scaled to children with and without obesity to explore the interplay of obesity, age, and pharmacogenomics.