From: Niurys.CS <*amaranthfan*>

Date: Tue, 23 Apr 2019 07:34:17 -0500

Dear All,

I'm working on the population pharmacokinetics of a mAb, in this study

4 dose levels (50, 100, 200 and 400 mg) were evaluated. I tested

different models, but none of them fit well; that's why I decided to

find for each dose level the best model. I found the two lower dose

levels fitted to Michaelis Menten + CL linear model and the two higher

dose levels fitted to QSS Rtot model.

I think if I use this code, I'll find the best model for my data, so I

appreaciate your suggestions:

$PK

TVCL= THETA(1)

TVV1= THETA(2)

TVQ = THETA(3)

TVV2 = THETA (4)

TVKM = 0

TVVM = 0

IF(DOS.LT.200) THEN

TVKM = THETA (5)

TVVM = THETA (6)

TVKSS = 0

TVKINT = 0

TVKDEG = 0

TVRMAX = 0

IF(DOS.GT.100) THEN

TVKSS = THETA (7)

TVKKINT = THETA(8)

TVRMAX = THETA(9)

ENDIF

K = CL/V1

K12 = Q/V1

K21 = Q/V2

S1 = V1

;----------------------------------

$DES

CONC=0.5*(A(1)/V1-RMAX-KSS)+0.5*SQRT((A(1)/V1-RMAX-KSS)**2+4*KSS*A(1)/V1)

DADT(1) = -(K+K12)*CONC*V1+K21*A(2)-KINT*RMAX*CONC*V1/(KSS+CONC)-VM*CONC*=

V1/(KM+CONC)

DADT(2) = K12*CONC*V1-K21*A(2)

Thank you,

Regards,

Niurys de Castro

--

MSc Niurys de Castro SuĂˇrez

Profesor Asistente FarmacometrĂa

Investigador Agregado

Departamento Farmacia

Instituto de Farmacia y Alimentos, Universidad de La Habana

Cuba

Received on Tue Apr 23 2019 - 08:34:17 EDT

Date: Tue, 23 Apr 2019 07:34:17 -0500

Dear All,

I'm working on the population pharmacokinetics of a mAb, in this study

4 dose levels (50, 100, 200 and 400 mg) were evaluated. I tested

different models, but none of them fit well; that's why I decided to

find for each dose level the best model. I found the two lower dose

levels fitted to Michaelis Menten + CL linear model and the two higher

dose levels fitted to QSS Rtot model.

I think if I use this code, I'll find the best model for my data, so I

appreaciate your suggestions:

$PK

TVCL= THETA(1)

TVV1= THETA(2)

TVQ = THETA(3)

TVV2 = THETA (4)

TVKM = 0

TVVM = 0

IF(DOS.LT.200) THEN

TVKM = THETA (5)

TVVM = THETA (6)

TVKSS = 0

TVKINT = 0

TVKDEG = 0

TVRMAX = 0

IF(DOS.GT.100) THEN

TVKSS = THETA (7)

TVKKINT = THETA(8)

TVRMAX = THETA(9)

ENDIF

K = CL/V1

K12 = Q/V1

K21 = Q/V2

S1 = V1

;----------------------------------

$DES

CONC=0.5*(A(1)/V1-RMAX-KSS)+0.5*SQRT((A(1)/V1-RMAX-KSS)**2+4*KSS*A(1)/V1)

DADT(1) = -(K+K12)*CONC*V1+K21*A(2)-KINT*RMAX*CONC*V1/(KSS+CONC)-VM*CONC*=

V1/(KM+CONC)

DADT(2) = K12*CONC*V1-K21*A(2)

Thank you,

Regards,

Niurys de Castro

--

MSc Niurys de Castro SuĂˇrez

Profesor Asistente FarmacometrĂa

Investigador Agregado

Departamento Farmacia

Instituto de Farmacia y Alimentos, Universidad de La Habana

Cuba

Received on Tue Apr 23 2019 - 08:34:17 EDT