NONMEM Users Network Archive

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two compartment nonlinear elimination

From: Chiaying Lin <cylin292>
Date: Tue, 8 Sep 2015 23:14:37 +0800

Dear NMusers
I'm modeling for a mAb. Below is 12 subjects's individual predicted plot ,
it seems that nonlinear elimination (Michaelis-Menten) model can fit the
data well. However, when running the control stream (two compartment models
with linear and non-linear elimination), the resulting Q THETA SE% and
OMEGA SE% are quite large even thought successful minimization.From the
Correlation Matrix , I find that THETA (1) (VMAX) and THETA(2) (KM)are
highly correlated (9.67E-01). Another problem is the .fit file can't be

 Does re-parameterization helpful ? or need to change to other models?

Any suggestions for solving the problems are highly appreciated.

(control stream will be send in another e-mail)

Received on Tue Sep 08 2015 - 11:14:37 EDT

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