Tlag is the time prior to the first measurable (non-zero) concentration.
Can you please share the demo project? I could not locate the demo project from your link above. Quoting WinNonlin’s 5.2 online help (Noncompartmental analysis > Plasma or serum data > Table B-3.): Tlag Extravascular input (model 200) only. Hi Serge: I have a similar question about modeling IV and SC together, with SC showing flip-flop kinetics. If you are deconvoluting oral (slow release) against an oral solution (to simulate in vivo dissolution), you will need to fit an exponential model to the oral (solution or IR) data to obtain the coefficients and exponents required for the deconvolution analysis in WinNonlin. Look at it and you can see that in this example Ka is smaller than ke and the fit is for both sets together. The oral data can then be entered as the measured values. When you do that and uncheck the sort button, you can also reset the time to zero when you give the SC dose. The assumption is that these are 2 separate sets of observation but with common PK.
I also used the reset tab to washout all the influence of the IV data when I gave the SC. What I did is to give you data where the model parameters are the same across the 2 routes except that I added bioavailability for SC route. If that is the case, you cannot fit both together assuming same model parameters. Here in your example, the problem seems that all the PK parameters may be different across the 2 routes.
Serge ĭear Aiqun I am attaching a demo project that shows you how to model both IV and SC together(you need to use the graphical feature and add an IV dose when taking as template extravascular input). Look at it and you can see that in this example Ka is smaller than ke and the fit is for both sets together. It generates the graphs, tables, and output worksheets required for regulatory submission.
It also supports creation of custom models to enable fitting and analysis of clinical data. The assumption is that these are 2 separate sets of observation but with common PK. Phoenix WinNonlin includes a large library of pharmacokinetic, pharmacodynamic, noncompartmen-tal, PK/PD linked, and indirect response models. Here in your example, the problem seems that all the PK parameters may be different across the 2 routes. Exercise 9 Building a user model in WinNonlin: construction and validation of a. I am attaching a demo project that shows you how to model both IV and SC together(you need to use the graphical feature and add an IV dose when taking as template extravascular input).