Skip Navigation LinksHome > January 2014 - Volume 33 - Issue 1 > Population Pharmacokinetics of Intravenous Acyclovir in Pret...
Pediatric Infectious Disease Journal:
doi: 10.1097/01.inf.0000435509.75114.3d
Antimicrobial Reviews

Population Pharmacokinetics of Intravenous Acyclovir in Preterm and Term Infants

Sampson, Mario R. PharmD*†; Bloom, Barry T. MD; Lenfestey, Robert W. MD, MHS*; Harper, Barrie BSMT (ASCP)*; Kashuba, Angela D. PharmD; Anand, Ravinder PhD§; Benjamin, Daniel K. MD, PhD, MPH*; Capparelli, Edmund PharmD; Cohen-Wolkowiez, Michael MD, PhD*; Smith, P. Brian MD, MPH, MHS*

Collapse Box

Abstract

Background:

Acyclovir is used to treat herpes infections in preterm and term infants; however, the influence of maturation on drug disposition and dosing requirements is poorly characterized in this population.

Methods:

We administered intravenous acyclovir to preterm and term infants <31 days postnatal age and collected plasma samples. We performed a population pharmacokinetic analysis. The primary pharmacodynamic target was acyclovir concentration ≥3 mg/L for ≥50% of the dosing interval. The final model was simulated using infant data from a clinical database.

Results:

The analysis included 28 infants (median 30 weeks gestation). Acyclovir pharmacokinetics was described by a 1-compartment model: clearance (L/h/kg) = 0.305 × [postmenstrual age (PMA)/31.3 weeks]3.02. This equation predicts a 4.5-fold increase in clearance from 25 to 41 weeks PMA. With proposed dosing, the pharmacodynamic target was achieved in 91% of infants: 20 mg/kg every 12 hours in infants <30 weeks PMA; 20 mg/kg every 8 hours in infants 30 to <36 weeks PMA and 20 mg/kg every 6 hours in infants 36–41 weeks PMA.

Conclusions:

Acyclovir clearance increased with infant maturation. A dosing strategy based on PMA accounted for developmental changes in acyclovir disposition to achieve the surrogate pharmacodynamic target in many infants.

Copyright © 2014 by Lippincott Williams & Wilkins

Login

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.