Population Pharmacokinetics of Darbepoetin in Infants Following Single Intravenous and Subcutaneous Dosing.
Document Type
Article
Publication Date
6-1-2017
Abstract
Darbepoetin alfa (Darbe) is a hyperglycosylated analogue of recombinant human erythropoietin (Epo). The aim of this study was to develop a population pharmacokinetic model for Darbe following intravenous (i.v.) and subcutaneous (s.c.) administration to infants. Data from 2 infant clinical studies (a single i.v. dose study following a 4 μg/kg dose of Darbe, and a single s.c. dose study following 1 μg/kg or 4 μg/kg dose of Darbe) were combined and analyzed simultaneously using nonlinear mixed-effect modeling approach. Darbe population pharmacokinetics was well described by a 2-compartment model with first-order elimination. The covariate analysis identified significant impact of gender on clearance and bodyweight on volume of distribution. The clearance of Darbe was estimated to be 0.050 L/h/kg in male infants and 0.031 L/h/kg in female infants. The predicted population mean value of Vp is 0.84 L/kg, which is associated with the subject's bodyweight (p < 0.05). Following s.c. administration, the estimated absorption rate (i.e., ka) of Darbe was 0.062 L/h. The model provides a suitable starting point for the development of further pharmacokinetic-pharmacodynamic models in infants in a variety of disease settings. Because the covariate-pharmacokinetic parameter relationships were identified in only 22 infants, further investigation with larger sample size is warranted.
Publication Title
Journal of pharmaceutical sciences
ISSN
1520-6017
Volume
106
Issue
6
First Page
1644
Last Page
1649
Recommended Citation
An, Guohua; Robin K Ohls; Robert D Christensen; John A Widness; Donald M Mock; and Peter Veng-Pedersen.
"Population Pharmacokinetics of Darbepoetin in Infants Following Single Intravenous and Subcutaneous Dosing.."
Journal of pharmaceutical sciences