Re: One vs two compartments
From: "Sam Liao" <sliao@pharmaxresearch.com>
Subject: Re: One vs two compartments
Date: Fri, 27 Jul 2001 10:34:29 -0400
Pete:
The bias obviously will depend on the contribution of the second phase to
the total AUC. I did a simulation of the same case a year ago. In this
simulation, frequent PK samples were collected only during the absorption
phase and alpha phase (over 24 hr). Non-compartmental method (NCA) was used
to calculate clearance (CL) and volume of distribution (V). The same data
were also analyzed by NONMEM using a two-compartment model and fixed the V3
and Q to the mean parameter estimates obtained from historical data. The
results (see figure1 attached) showed that CL was significantly
over-estimated by NCA method, but not by NONMEM.
Best regards,
Sam Liao, Ph.D.
PharMax Research
270 Kerry Lane,
Blue Bell, PA 19422
phone: 215-6541151
efax: 1-720-2946783