Saturable absorption of sorafenib in patients with solid tumors: A population model - Abstract

Laboratoire de pharmacologie-toxicologie, Service de Pharmacie, Hôpital Cochin, 75014, Paris, France.

 

Sorafenib is an oral tyrosine kinase inhibitor approved for the treatment of advanced renal cell carcinoma and hepatocellular carcinoma. By using a population approach, this study aimed to characterise its pharmacokinetics. Plasma concentration-time data (n = 372) from 71 patients under sorafenib were analysed using nonlinear mixed-effect modelling to estimate population pharmacokinetic parameters, as well as relationships between these parameters and different covariates (demographic, biological). Simulations were done to compare different daily dosing regimens in a context of dose-escalation. A 1-compartment model with saturated absorption, first-order intestinal loss and elimination best described the pharmacokinetics of sorafenib. Absolute bioavailability significantly dropped with increasing daily doses of sorafenib. AUC increased less than proportionally with increasing doses [47.3 (41.3-63.3), 60.3 (56.3-64.4), 71.4 (51.3-99.1), 75.9 (45.5-100.9) mg/L.h for 400, 800, 1,200 and 1,600 mg/day, respectively]. According to the simulations, dividing the daily dose in three or four doses for daily dose >800 mg would significantly increase AUC compared with a twice daily dosing regimen (101.7 vs 81.6 mg/L.h for 400 mg q8h and 600 mg q12h respectively; 131.6 vs 91.5 mg/L.h for 400 mg q6h and 800 mg q12h, respectively). Thrice daily regimen may be most suitable in a context of dose-escalation (>800 mg/day) in non-responders to standard-dosing regimen.

Written by:
Hornecker M, Blanchet B, Billemont B, Sassi H, Ropert S, Taieb F, Mir O, Abbas H, Harcouet L, Coriat R, Dauphin A, Goldwasser F, Tod M.   Are you the author?

Reference: Invest New Drugs. 2011 Oct 18. Epub ahead of print.
doi: 10.1007/s10637-011-9760-z

PubMed Abstract
PMID: 22006162

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