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RE: Simultaneous vs sequential for modeling parent AND metabolites in pop PK

From: Hussein, Ziad <Ziad.Hussein>
Date: Tue, 9 Dec 2008 16:40:54 -0000

Hi Atul,

The emails must have crossed. However, this is not the FDA view based
on a recent experience where I have to repeat the analysis using the
simultaneous approach.

Kind regards,
Dr Ziad Hussein
Senior Director, Pharmacometrics
ICON Development Solutions
United Kingdom

-----Original Message-----
From: owner-nmusers
On Behalf Of Bhattaram, Atul
Sent: 09 December 2008 16:22
To: Xiao, Alan; nmusers
Subject: RE: [NMusers] Simultaneous vs sequential for modeling parent
AND metabolites in pop PK

Hello Alan

I have used a sequential approach in the past as the model was more
stable with lesser run time.


Venkatesh Atul Bhattaram
Office of Clinical Pharmacology
US Food and Drug Administration

"The contents of this message are mine personally and do not necessarily
reflect any position of the Government or the Food and Drug

-----Original Message-----
From: owner-nmusers
On Behalf Of Xiao, Alan
Sent: Tuesday, December 09, 2008 11:02 AM
To: nmusers
Subject: [NMusers] Simultaneous vs sequential for modeling parent AND
metabolites in pop PK

Dear All,

I know this is an old topic but would like to see the statistics.

When you have to develop a pop PK model for both parent and active
metabolites, which approach do you prefer or have you used most:
simultaneous or sequential? Which way do you think is more scientific? I
heard comments saying that the simultaneous approach is not scientific.


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Received on Tue Dec 09 2008 - 11:40:54 EST

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