TAD from PKPD model

Phoenix Certara Forums Modelling and Simulation
1

I have a PKPD model with Vehicle or different drug dosages. there is a clear vehicle effect in the data I need to take into account. The effects are in time after dosing but the same subjects were dosed with both vehicle or drug on different occasions. I would like to analyse the data using TAD instead of time. However, when I set the dose to zero for my vehicle dosing it is not recognised as a dose so the TAD analysis fail. How do I set a Vehicle dose so that the time resets after vehicle dosing?

BR Frederik

2

Hi Frederik,

I was thinking about a workaround, but the simplest I could come up with is to give a dose amount close to 0, e.g. 0.0000000001. This will by no means affect your results.

I was thinking about replacing the dosepoint statement with a sequence loop and using the dosing information as covariate, but that is far trickier.

Bernd

3

also maybe a dobefore doafter in the dosepoint might help you build the variable you need