[NMusers] Modeling Cmin and Tmin

Dear NMUser, I am a beginner in NONMEM and I have a question regarding modeling Cmin and Tmin. I have data of a biomarker which decreases after drug intake and I want to determine the minimum change from baseline (Cmin) as well as the corresponding time (Tmin). I tried different models but t

RE: [NMusers] Modeling Cmin and Tmin

Dear Friederike, Please, step back for one minute and try to understand what you want to find out: You are applying a nonlinear mixed-effects modelling program to obtain parameter values for your model. All parameters in your model are random variables. Some have a mean of zero (ETAs, EPSs) som

[NMusers] Phoenix WinNonlin 6.2 released, IVIVC toolkit can now be incorporated into workflows

Pharsight - A CertaraT Company  is proud to announce the launch of the next generation of the Phoenix platform for integrated PK/PD modeling and simulation.  The Phoenix platform combines four tools within a single graphical-user-interface to create a fully integrated, regulatory compliant mode

AW: [NMusers] Modeling Cmin and Tmin

Dear Joachim, thank you for your explanations. My plan was not to determine the typical value or distribution for this parameters (as THETA or ETA) but to determine the minimum biomarker concentration for each ID with the appropriate time for further correlation studies with outcome etc. I tr

[NMusers] Two sequential absorption processes

Dear NonMEM users, I want to code a two sequential absorption processes with 2 CMT: zero-order absorption for the first 2.99 hours and then first-order absorption for the rest time. My code is listed as below. My question is when I change K0 (zero-order absorpption rate), the predicted concen

RE: [NMusers] Modeling Cmin and Tmin

Friederike, You can just as well enrich the individual records of each ID with additional times using EVID=2. Then you get predictions for all compartments at these additional times for each ID with its optimal set of ETA estimates without altering the OBFV or the estimates. You can then list t

AW: [NMusers] Modeling Cmin and Tmin

Joachim, Yes, I included dummy observations before each new dosing time, therefore, it is maybe the easiest way to read my table in R and let R determine the minimum biomarker conc for each ID Thank you very much, Friederike Von: Joachim Grevel [mailto:jgre...@o2.co.uk] Gesendet: Mittwo

RE: [NMusers] Modeling Cmin and Tmin

Dear Friederike, Below are an example of code for obtaining Cmax and Tmax for a simple PK model (I know there are analytical solutions for this, it is only intended as a simple example of a general approach). This can easily be manipulated to instead obtain Cmin and Tmin with another kind of mo

RE: [NMusers] Two sequential absorption processes

Hello, I think that the model that you refer to is called the KOKA absorption model (Holford et al. J Pharmacokinet Biopharm. 1992; 20:421-42). You don't need $DES, it can be easily coded using ADVAN4 (it will greatly reduce your run time). I guess you know what fraction of the dose enters as a

Re: [NMusers] Two sequential absorption processes

2011/4/6 Liu Dongyang > Dear NonMEM users, > > I want to code a two sequential absorption processes with 2 CMT: > zero-order absorption for the first 2.99 hours and then > first-order absorption for the rest time. My code is listed as below. My > question is when I change K0 (zero-order absorp