# RE: Generating Cmax at end of infusion

From: Steve Olson <steve.olson>
Date: Tue, 6 Apr 2010 10:26:32 -0700

Hi Paul,
Is DUR modeled or explicit? If explicit then it seems as easy approach woul=
d be to include an EVID=2 record at the stated end of infusion and calcul=
ate the anti-log as you and Nick indicate.
Steve

Stephen C. Olson
steve.olson
734 268 6867
www.clinpharmres.com

From: owner-nmusers
Behalf Of Nick Holford
Sent: Tuesday, April 06, 2010 1:03 PM
Cc: NMUSERS
Subject: Re: [NMusers] Generating Cmax at end of infusion

Paul,

TIME is the data record time in \$PK and \$ERROR.
T is the time between record TIMEs in \$DES.

In order to use your method you need to have a record with TIME in your dat=
a set that is equal to DUR.

In that case you can use this code which also sets CMAX to 0 if an individu=
al does not have DUR.EQ.TIME. If you don't do this then you will get the CM=
AX from the last individual who did have DUR.EQ.TIME.

IF (DUR.EQ.TIME) THEN
CMAX=EXP(Y)
ELSE
CMAX=0
ENDIF

Paul Hutson wrote:
G'day.
I would like to generate a concentration at the end of an infusion of durat=
ion DUR.
I am using ADVAN3 TRANS4 with log transformed data. Here is what I have t=
ried, but I am getting an error that the parameter 'T' that I understood to=
be the machine time is undefined. Can anyone suggest a proper way to give=
set Cmax=exp(Y) at the end of the infusion of length DUR?
Many thanks in advance.
Paul
\$PK
...
TT=TIME

\$ERROR
;I've also tried
;TT=TIME
;TT=T
IPRE=F
EDV=EXP(DV)
W=1
IF(F.GT.0) W=F
IRES=F-EDV
IWRE=IRES/W
LOGF=LOG(0.0001)
IF (F.GT.0) LOGF=LOG(F)
Y=LOGF+EPS(1)
;GENERATE CMAX AT END OF INFUSION (DUR)
IF(DUR.EQ.TT) CMAX=EXP(Y)
--

Paul R. Hutson, Pharm.D.
Associate Professor
UW School of Pharmacy
777 Highland Avenue
Tel 608.263.2496
Fax 608.265.5421
Pager 608.265.7000, p7856

--

Nick Holford, Professor Clinical Pharmacology

Dept Pharmacology & Clinical Pharmacology

University of Auckland,85 Park Rd,Private Bag 92019,Auckland,New Zealand

tel:+64(9)923-6730 fax:+64(9)373-7090 mobile:+64(21)46 23 53

email: n.holford

http://www.fmhs.auckland.ac.nz/sms/pharmacology/holford

Received on Tue Apr 06 2010 - 13:26:32 EDT

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