indirect response model

From: "kai wu" kaiwu77@yahoo.com Subject: [NMusers] indirect response model Date: Wed, August 18, 2004 9:50 pm Dear NONMEM users, I am trying to use ADVAN6 to fit a indirect response model for a endogenous substance suppression by drug. $DES DADT(1)=-KA*A(1) DADT(2)=KA*A(1)+K21*A(3)-K12*A(2)-K10*A(2) DADT(3)=K12*A(2)-K21*A(3) CP=A(2)/S2 EFF=1-CP*0.1/(EC50+CP*0.1) DADT(4)=Rcort*EFF-KE*A(4) The baseline follow a circadian rhythm, this rhythm (Rcort) is controlled by four parameters which I want to estimate. I do have baseline profile for each subject. The question is how should I set up the data records and control stream to incorparate the baseline into my dataset. I was able to fit the data without baseline data, but the prediction for time 0 is all 0. Since in my case Rcort is not a parameter to estimate, the F4 method does not work for me. Thanks in advnace! Kai Kai Wu Department of Pharmaceutics University of Florida Gainesville, Fl Office phone #: 352-846-2730