What are the pharmacokinetics of recombinant Factor VIIa?
  Lindley and colleagues investigated the single-dose pharmacokinetics of recombinant Factor VIIa in 15 patients with hemophilia A or hemophilia B with inhibitors. Three dose levels (17.5, 35.0, and 70.0 micrograms/kg) were evaluated in both the nonbleeding and bleeding state. FVII activity was determined at baseline; 10, 20, and 60 minutes; and 2, 4, 6, 12, and 24 hours after recombinant Factor VIIa administration. The elimination half-life for each dose level was from 2.6 to 2.84 hours based on dosing that ranged from 17.5 micrograms/kg to 70 micrograms /kg. The results show that the mean half-life of recombinant Factor VIIa is independent of dose level. Other data drawn from the pharmacokinetic study demonstrate that the volume of distribution of recombinant Factor VIIa, similar to the half-life of recombinant Factor VIIa, is dose independent. In addition, recombinant Factor VIIa was shown to distribute in a volume corresponding to two to three times that of the plasma volume. Lower mean in vivo plasma recovery was seen during bleeding episodes compared to nonbleeding states. This observed difference in recovery between bleeding (46.5%) and nonbleeding (48.7%) states was statistically significant (P=0.0006; 95% CI, 1.8% to 40%). However, the number of samples obtained was small, and further data should be obtained to corroborate these results. Overall, the data show that the pharmacokinetics of single-dose recombinant Factor VIIa were linear in the dose range evaluated. Lindley CM et al. Clin Pharmacol Ther 1994;55:638-648.
 
 
     
back to questions
Home
end of questions
Prescribing Info - Questions - Drug Info - Links - PDA Software - Article Summaries - Slideshows - Review Articles - What's New
 
© Copyright 1999-2017 DocMD.com. All Rights Reserved.