Parameter names missing in results for PD modeling

Phoenix Certara Forums Modelling and Simulation
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I’m running a simple PD fit to 90 observations using Model 105, Sigmoidal Emax without offset. My results look as expected but the output has missing for each of the three parameter names; Emax, EC50 and Gamma. I’m using the WNL generated initial estimates and bounds. Reducing the sample size to 45 has does not make the problem go away.

I’ve been corresponding with Simon but he had to leave for the day. He suggested the following, but I don’t know how to look up qc 7145 and I’m not sure what “Phoenix model engine” is referencing. Is he suggesting NLME? There many Phoenix models and I thought Phoenix referred to the environment and not to any certain program. I’m using the “Pharmacodynamic Models” program.

Can anyone tell me how to look up qc 7145 or what Phoenix model might be better?

Kind regards, Jim

Settings from PD EoO Weeks 2 & 6.rtf (933 Bytes)Core output from PD EoO Weeks 2 & 6.rtf (12 KB)

James, sorry I’m finishing up for the day / w/e so I’m going to pass this on to support as I believe you’ve hit an issue logged as qc 7145 ‘Parameters in results worksheets from PK Modelling may appear with the name of MISSING’

From my brief read of the problem it seems that with less doses /less profiles it maybe go away i.e. you’d have to break your dataset up.

OR you could use the Phoenix model engine instead and that won’t suffer the same problem.

2

Bath and bed time finished for my little girl so, yes I can explain a little more.

  1. the QC number refers to an internal database at Pharsight that I think would help support

  2. if you send to ‘phoenix model’ then you can set the equivalent WNL classic model

  3. click this button

4)then select the equvialent model e.g. Emax then in the second drop down 105

  1. then click Apply

Simon

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select_Emax_forPD.jpg
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Thanks, now I see what you are talking about! Thanks.

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For the record under the Phoenix environment or platform you have lot of different “objects” or data management and analysis tools of which we have classical WNL PK / PD models but also the Phoenix Model Object.

The Phoenix Model object uses the latest modeling language called PML and not only support individual modeling like the classical WNL model does but also mixed effects models (NLME). You have also much more flexibility in PML.

I advise all users to start porting their code to Phoenix model language PML which is much more powerful.

Samer