Re: [NMusers] backward integration from t-a to t

email: - From: Pavel belonon...@optonline.net Date: Thu, 16 Jan 2014 13:05:54 -0500 (EST) To:lgibian...@quantpharm.com,nmusers@globomaxnm.com Subject: RE: [NMusers] backward integration from t-a to t Hello Leonid, Thank you bein helpful. You got the main point. AUC

RE: [NMusers] backward integration from t-a to t

05:54 -0500 (EST) To: lgibian...@quantpharm.com, nmusers@globomaxnm.com Subject: RE: [NMusers] backward integration from t-a to t Hello Leonid, Thank you bein helpful. You got the main point. AUC is a better predictor than concentration, but it has to disppear very slowly but surely. A pote

Re: [NMusers] backward integration from t-a to t

om <mailto:nmusers@globomaxnm.com> Subject: RE: [NMusers] backward integration from t-a to t Hello Leonid, Thank you bein helpful. You got the main point. AUC is a better predictor than concentration, but it has to disppear very slowly but surely. A potential challenge is biological meaning of th

Re: [NMusers] backward integration from t-a to t

...@quantpharm.com, nmusers@globomaxnm.com Subject: RE: [NMusers] backward integration from t-a to t Hello Leonid, Thank you bein helpful. You got the main point. AUC is a better predictor than concentration, but it has to disppear very slowly but surely. A potential challenge is biological meaning of this

RE: [NMusers] backward integration from t-a to t

: [NMusers] backward integration from t-a to t Hello Leonid, Thank you bein helpful. You got the main point. AUC is a better predictor than concentration, but it has to disppear very slowly but surely. A potential challenge is biological meaning of this approach. It will be necessary to

RE: [NMusers] backward integration from t-a to t

Hello Leonid, Thank you bein helpful. You got the main point. AUC is a better predictor than concentration, but it has to disppear very slowly but surely. A potential challenge is biological meaning of this approach. It will be necessary to explain it to the biologists, who ask question l

RE: [NMusers] backward integration from t-a to t

Hello Jacob,   It is the best to have fully-mechanistic model.  Unfortunately, we rarely have the data to build such model.  So, approximations are needed.  In case we have the data, we know how to build the model; we understand the mechanisms.    An effect compartment model does no

RE: [NMusers] backward integration from t-a to t

Pavel: I am glad someone informed you of the ALAG option for handling your problem. My colleague w...@buffalo.edu and his associates have published on the general aspects of time delay differential equations, of which yours is a particular example. Although Jacob Ribbi

RE: [NMusers] backward integration from t-a to t

Jello Jacob,   Someone genious just helped me.  Tlag can be used.  How did I miss such simple solution?    I was talking about multiple doses.  There are cases AUC is better predictor than concentration (for example, long duration of treatment is needed; very slow but good drug effe

RE: [NMusers] backward integration from t-a to t

Hi Pavel, I agree with you it is not uncommon to have AUC drive efficacy or safety endpoints. However, you seem to have the impression this is commonly done using cumulative AUC and I can assure you that is rarely the case. I have only seen that for safety endpoints where it has been justified

RE: [NMusers] backward integration from t-a to t

Pavel, I think one can use equation DADT(2)=C-K0*A(2) where C is the drug concentration. When K0=0, A2 is cumulative AUC. When k0>0, A2 would represent something like AUC for the interval prior to the current time The length of the interval would be proportional to 1/K0 (and equal to infinity