Getting secondary PK parameters

Phoenix
1

Hello,

Hope everyone is doing well!

I have a project I am working on with both intense and sparse PK sampling. I was able to find a good model fit (2 compartment, additive, with enterohepatic recirculation) and that seems to capture the data well. I want to try adding/testing covariates, and I am getting a little stuck on how to go forward. How do I get my parameters like Cmax, AUC, etc. to assess covariate effect? Do I need them or do I just look at the Cl, Vd, and Ka? And either way, how do I get the Cmax, etc. estimates for my population? I saw a post talking about similar question and they were told to use the posthoc values as parameters but it is confusing me. Do I need to do simulation to get those population estimates?

I am new to NLME-MLM modeling in Phoenix, so I would appreciate any advice I can get!

2

once you have a model the easiest way is to simulate pk profile from your model and then compute what you need example AUC, CMAX. for models that are more complex like with enterohepatic recirculation the usual formula does not apply.

the good thing if you have a model in Phoenix your can easily simulate using RsNLME and incorporate the uncertainty with some coding