To establish the pharmacokinetic profile of activated recombinant
coagulation factor VII (
rFVIIa;
NovoSeven in children with
haemophilia A, and to compare it with the pharmacokinetic profile in adults with
haemophilia A. Twelve children (2-12 years) received one single dose of
rFVIIa 90 and 180 micrograms kg(-1) in randomized order separated by a washout period of 48 h to 1 month. Six adults (18-55 years) received a single dose of
rFVIIa 90 micrograms kg(-1). The pharmacokinetic analyses were based on a non-compartmental method. In children, the plasma level of FVII increased proportionally with the dose. The total body clearance normalized for
body weight was significantly faster in children than in adults (
FVII:C, 58 vs. 39 mL kg(-1) h(-1) and FVIIa, 78 vs. 53 mL kg(-1) h(-1), P < 0.05). A trend towards a larger volume of distribution at steady-state in children than in adults was observed (P > 0.05). Dose proportionality was established for plasma concentrations of FVII in children with
haemophilia A at the dose levels investigated (90 and 180 micrograms kg(-1)
rFVIIa). Following administration of
rFVIIa 90 micrograms kg(-1), significantly faster clearance was observed in children compared with adults, suggesting that higher doses of
rFVIIa may be needed to achieve the same plasma levels as in adults.