RE: modeling of total concentration of two drugs with different kinetics in NONMEM

From: Bill Denney Date: April 25, 2012 technical Source: mail-archive.com
Hi Yaming, This simplifies things significantly. The first dose will (hopefully fully) define the PK of drug 1. The dose of drug 2 will be modeled as the sum of the two. Since you have only drug 1 at the beginning, you should be able to model the full time course with: F=A(2)/V2 + A(3)/V3 Then for the first few days, A(3)/V3 (concentration of drug 2) will be zero. Thanks, Bill
Quoted reply history
From: [email protected] [mailto:[email protected]] On Behalf Of Yaming Hang Sent: Wednesday, April 25, 2012 10:43 AM To: Retsilisitsoe Moholisa; [email protected] Subject: RE: [NMusers] modeling of total concentration of two drugs with different kinetics in NONMEM Hi Retsilisitsoe, The two drugs are given at different time (a few days apart). The first drug is a maintenance drug without dosing history, but subjects are assumed to wash out the drug sufficiently. In period 1, subjects were given a single IV infusion of first drug, a few days later, subjects were given the second drug (IV infusion again), where the first drug is not necessarily completely cleared. Thanks, Yaming From: Retsilisitsoe Moholisa [mailto:[email protected]] Sent: Wednesday, April 25, 2012 10:23 AM To: Yaming Hang; [email protected] Subject: Re: [NMusers] modeling of total concentration of two drugs with different kinetics in NONMEM Dear Yaming I have two questions. 1.Were the drugs given at the same time as a fixed dose combination? 2. Do you have PK when the drugs are give separately? >>> Yaming Hang <[email protected]<mailto:[email protected]>> >>> 2012/04/25 03:22 PM >>> Dear All, I’m trying to model in NONMEM the kinetics of two drug entities co-existing in the blood. Since the assay cannot differentiate these two entities, I only have the total concentration of these two in the blood. Does anyone has similar experience? Can you please share the NONMEM code? Thanks, Yaming Yaming Hang, Ph.D. Pharmacometrics Biogen Idec 14 Cambridge Center Cambridge, MA 02142 Office: 781-464-1741 Fax: 617-679-3463 Email: [email protected]<mailto:[email protected]> ### UNIVERSITY OF CAPE TOWN This e-mail is subject to the UCT ICT policies and e-mail disclaimer published on our website at http://www.uct.ac.za/about/policies/emaildisclaimer/ or obtainable from +27 21 650 9111. This e-mail is intended only for the person(s) to whom it is addressed. If the e-mail has reached you in error, please notify the author. If you are not the intended recipient of the e-mail you may not use, disclose, copy, redirect or print the content. If this e-mail is not related to the business of UCT it is sent by the sender in the sender's individual capacity. ###
Apr 25, 2012 Yaming Hang modeling of total concentration of two drugs with different kinetics in NONMEM
Apr 25, 2012 Retsilisitsoe Moholisa Re: modeling of total concentration of two drugs with different kinetics in NONMEM
Apr 25, 2012 Leonid Gibiansky Re: modeling of total concentration of two drugs with different kinetics in NONMEM
Apr 25, 2012 Bill Denney RE: modeling of total concentration of two drugs with different kinetics in NONMEM