7 replies to this topic

[Senka Radosevic]

Hi,

I am working on IVIVC case for modified release product, and I am able to get only linear correlation FraAbs vs FraDiss (using IVIVC Toolkit).

However, it’s likely that there is a correlation, but not linear.

 

Questions:

Is there a possibility to get non-linear equation using IVIVC Toolkit?

How to do that?

Is it possible to set one correlation equation up to e.g. 20% dissolved, and another correlation equation for later ?

 

Thanks in advance

Senka

[Simon Davis]

Sure Senka it's possible;  Select the User Specified option button to create a custom correlation model using the WinNonlin ASCII modeling language.  There is some info in the Phoenix IVIVC Toolkit 2.2 User's Guide.pdf as well an example of custom code on here;

 

http://www.certara.c...osters/?hl=aaps

 

Please let us know how you get on.

  Simon.

[Simon Davis]

Someone recently asked for more details on the ASCII code to help with writing their IVIVC user models, for those of you that this would help; please look at Chapter 10, User Models in the attached WinNonlin 5.3 User guide.

 

  Simon.

Attached Files

•  WinNonlin User's Guide 5.3.pdf   5.17MB   68566 downloads

[harishkaushik]

Hello Simon,

Can you share an example code for doing the same or example project

 

Regards

Harish

[Simon Davis]

Harish, please follow the link in post number 2!

 

  Simon.

[harishkaushik]

Hello Simon,

 

I have read an article on "developing Nonlienar IVIVC for Upadacitinib" where the authors have used A user-specified non-linear IVIVC was evaluated by fitting a non-linear Emax model to scale the Tvitro to the Tvivo,  

How can we code the same in IVIVC, any insights will help

 

Link to the paper

https://link.springe...2248-019-0378-y

 

Regards

Harish

[Nuno Elvas Silva]

Dear all

 

I'm also trying to build a non-linear correlation using Upadacitinib paper as example. In the paper a non-linear Emax model to scale the Tvitro to the Tvivo was implemented:

 

Tvitro = ((A1*Tvivo)/(A2+Tvivo))-B2

 

I'm using the following code:

 

T = ((A1 * X)/(A2 * X))

IF T > 0 THEN

  DISS = IVINTERP(T)

ELSE

  DISS = 0

ENDIF

F = A1 * DISS

 

When checking, a message shows up:

 

*** ERROR 10031 *** ATTEMPT TO DIVIDE BY ZERO.  PROGRAM TERMINATED.   Line =   3:   Variable = -------------------------------------------------------------------OK

 

And it is not possible to Build Correlation.

 

Any suggestion how to implement such a non linear time scaling?

[Simon Davis]

Nuno can you email your project to support@certara.com for us to take a look.