From:"Kakkar, Tarundeep"
Subject:[NMusers] 2-cmpt PK model using ADVAN6
Date:Thu, 13 Jun 2002 15:17:26 -0400
Hi,
I'm trying to write a differential model using ADVAN6. However, I can't get
it to converge. I had initially fitted the same data to ADVAN4 TRANS4 and
the fits were fine. Also, when I tried to simulate using POSTHOC estimates
from the ADVAN4 fit, I got very different numbers. The model and input
files are as follows:
$PROB
$INPUT C DROP=ID TIME DV AMT II ADDL SS CMT
$DATA PK.csv IGNORE=C
$SUBROUTINE ADVAN6 TRANS=1 TOL=6
$MODEL NCOMP=3
COMP=(GUT)
COMP=(CENTRAL)
COMP=(PERIPH)
$PK
;PK parameters
TVCL=THETA(1)
TVV1=THETA(2)
TVQ=THETA(3)
TVV2=THETA(4)
TVKA=THETA(5)
CL=TVCL
V2=TVV1
Q=TVQ
V3=TVV2
KA=TVKA
$DES
C2=A(2)/V2
C3=A(3)/V3
DADT(1)=-KA*A(1)
DADT(2)=KA*A(1)+Q*(C3-C2)-CL*C2
DADT(3)=Q*(C2-C3)
$ERROR
Y=F*(1+ERR(1))
$THETA (30) ;CL
(780) ;V2
(1.09) ;Q
(141) ;V3
(1.45) ;KA
$OMEGA 0.1
$ESTIMATION MAXEVAL=9999 METHOD = 1 PRINT=1 NOABORT
;$COV
;$TABLE TIME DV PRED CL V2 Q V3 KA FILE=PK.tab NOPRINT ONEHEADER
C,ID,TIME,DV,AMT,II,ADDL,SS,CMT
,1,0,.,19500,12,17,.,1
,1,2,23.8,.,.,.,.,2
,1,3,20.6,.,.,.,.,2
,1,4,20.1,.,.,.,.,2
,1,6,19.9,.,.,.,.,2
,1,12,14,.,.,.,.,2
,1,48,28,.,.,.,.,2
,1,192,34.3,.,.,.,.,2
,1,216,37.1,.,.,.,.,2
,1,216,.,19500,12,.,1,1
,1,218,58.3,.,.,.,.,2
,1,219,71.4,.,.,.,.,2
,1,220,56.4,.,.,.,.,2
,1,222,54.7,.,.,.,.,2
,1,228,40.2,.,.,.,.,2
,1,264,8.03,.,.,.,.,2
,1,312,1.99,.,.,.,.,2
Thanks in advance for your help.
Tarun
2-cmpt PK model using ADVAN6
From:"Bachman, William"
Subject:RE: [NMusers] 2-cmpt PK model using ADVAN6
Date:Thu, 13 Jun 2002 15:42:38 -0400
Tarun,
At first glance, all that seems to be missing is a scaling factor:
S2=V2
Bill