NONMEM Modeling of Plasma + Urine Data

From: Tarek M Abouel Leil Date: November 21, 2006 technical Source: cognigencorp.com
From: "Abouel Leil, Tarek M. Ph.D." AbouelLeil.Tarek@mayo.edu Subject: [NMusers] NONMEM Modeling of Plasma + Urine Data Date: Tue, 21 Nov 2006 09:37:00 -0600 Hello, I am trying to simultaneously model the PK of a drug and its metabolite using NONMEM. I have plasma observations for the parent compound (17-AAG) and the metabolite (17-AG). I also have 24hr urine collection data for both compounds. When I tried to model this using ADVAN7 in NONMEM, it stops almost immediately with the following error: MONITORING OF SEARCH: 0PRED EXIT CODE = 1 0INDIVIDUAL NO. 1 ID=0.10100000E+03 (WITHIN-INDIVIDUAL) DATA REC NO. 4 THETA= 1.43E+04 2.42E+04 8.44E+04 8.96E+04 1.24E+04 2.13E+04 5.00E+04 NUMERICAL DIFFICULTIES OBTAINING THE SOLUTION. THE COEFFICIENT MATRIX IS ALGORITHMICALLY SINGULAR. 0PROGRAM TERMINATED BY OBJ MESSAGE ISSUED FROM ESTIMATION STEP AT INITIAL OBJ. FUNCTION EVALUATION 1THERE ARE ERROR MESSAGES IN FILE PRDERR 2006.11.20.1820.57 Here is the NONMEM control stream that I am using: $INPUT ID AMT EVID RATE TIME DV UVOL CMT BW BSA SEX AGE CRCL BR AP AST DOSE $DATA ..\data.dta IGNORE=# $SUBROUTINE ADVAN7 $MODEL COMP=(CENTRAL, DEFDOSE, DEFOBS) COMP=PERIPH COMP=METAB COMP=("URINE", NODOSE, INITIALOFF) COMP=("METABUR", NODOSE, INITIALOFF) $PK TVCL = THETA(1) CL = TVCL*EXP(ETA(1)) TVV = THETA(2) V = TVV * EXP(ETA(2)) K14 = CL/V S1 = V TVQ = THETA(3) Q = TVQ * EXP(ETA(3)) TVV2 = THETA(4) V2 = TVV2 * EXP(ETA(4)) K12 = Q/V K21 = Q/V2 TVCLM = THETA(5) CLM = TVCLM * EXP(ETA(5)) K13 = CLM/V TVCLMO = THETA(6) CLMO = TVCLMO * EXP(ETA(6)) TVV3 = THETA(7) V3 = TVV3 * EXP(ETA(7)) K35 = CLMO/V3 S3 = V3 S0=UVOL $ERROR ASY1=0 IF (CMT.EQ.1) ASY1=1 ASY2=0 IF (CMT.EQ.3) ASY2=1 ASY3=0 IF (CMT.EQ.4) ASY3=1 IPRED = F W = 1 IF (F.EQ.0) W=1 IRES = DV-IPRED IWRES = IRES/W Y=IPRED+ASY1*ERR(1)+ASY2*ERR(2)+ASY3*ERR(3)+(1-ASY1)*(1-ASY2)*(1-ASY3)*ERR(4) $THETA (0,14300.,) ; TVCL $THETA (0,24200.,) ; TVV $THETA (0,84400.,) ; TVQ $THETA (0,89600.,) ; TVV2 $THETA (0,12400.,) ; TVCLM $THETA (0,21300.,) ; TVCLMO $THETA (0,50000.,) ; TVV3 $OMEGA 0.25 ; ETATVCL $OMEGA 0.25 ; ETATVV $OMEGA 0.25 ; ETATVQ $OMEGA 0.25 ; ETATVV2 $OMEGA 0.25 ; ETATVCLM $OMEGA 0.25 ; ETATVCLMO $OMEGA 0.25 ; ETATVV3 $SIGMA 100 ; ERRSD17AAG $SIGMA 100 ; ERRSD17AG $SIGMA 100 ; ERRSD17AAG URINE $SIGMA 100 ; ERRSD17AG URINE $EST METH=0 MAXEVAL=9999 NOABORT POSTHOC PRINT=5 SIGDIGITS=5 $COVARIANCE The data file looks like this: #ID AMT EVID RATE TIME DV UVOL CMT 101 31500000 1 31500000 0 0 0 1 101 0 2 0 0 0 0 4 101 0 2 0 0 0 0 5 101 0 0 0 0.5 20 0 3 101 0 0 0 0.5 231 0 1 101 0 0 0 0.92 51 0 3 101 0 0 0 0.92 300 0 1 101 0 0 0 1.08 47 0 3 101 0 0 0 1.08 146 0 1 101 0 0 0 1.25 40 0 3 101 0 0 0 1.25 109 0 1 101 0 0 0 1.5 55 0 3 101 0 0 0 1.5 121 0 1 101 0 0 0 2 42 0 3 101 0 0 0 2 119 0 1 101 0 0 0 3 25 0 3 101 0 0 0 3 75 0 1 101 0 0 0 5 17 0 3 101 0 0 0 5 25 0 1 101 0 0 0 9 0 0 1 101 0 0 0 9 0 0 3 101 0 0 0 17 0 0 1 101 0 0 0 17 0 0 3 101 0 0 0 24 1993.956 904 -4 101 0 0 0 24 609.6032 904 -5 I was able to model the above data without urine observations, so I feel there must be something wrong with the way I am coding the urine compartments. I would really appreciate any advice. Thanks, Tarek A. Leil, Ph.D. Department of Oncology, Guggenheim 1311 Mayo Clinic 200 First Street SW Rochester, MN 55905 ph: 507-538-4227 fax: 507-266-5146 pgr: 08189
Nov 21, 2006 Tarek M Abouel Leil NONMEM Modeling of Plasma + Urine Data
Nov 23, 2006 Partha Nandy RE: NONMEM Modeling of Plasma + Urine Data