Estimation of dual Cmax

Dear Team,

I am with concentration data which has “2” Cmax. I would like to estimate both from concentration data profile. How Winnonlin can help me? With NCA setup do we have any option to do so?

Hi,

Cmax is defined as maximum concentration of a single profile in NCA. I take it that you have multiple peaks in your profile and you want to know at which times these are occuring and at which concentrations. This can only be done through compartmental modeling. Unfortunately, it can only be achieved through textual models. If you can share your data we can advise how to setup the model.

Bernd

As Bernd says you cna’t do this directly in NCA but you may also tabulate these ‘duplicate’ Cmaxs by using an inner join back to the original concentration sheet a bit like here partial AUCs (PHX6.4+) - Phoenix WNL basics - Certara Forums

if you’re still stuck you can post an example project so we can try to help you the last bit. Simon.

Hello,

If you are just interested in the observed second peak Cmax, you could merge the data, remove the highest concentration and run an NCA again. See attached project.

Ana Henry

Certara University

2Cmax.phxproj (850 KB)

[attachment=3810:Demonstration2cmax.phxproj]Hi D_Nil, i took Ana’s project and added my inner join to find other occurences of Cmax in the profile, was that what you wanted?

Simon.

Demonstration2cmax.phxproj (903 KB)