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RE: [NMusers] covariate on transit compartment model parameters

From: <R.terHeine_at_radboudumc.nl>
Date: Mon, 26 Sep 2016 11:11:41 +0000

Hi Jing,

Testing covariates on dispostition of your long acting injectable all depends on the pharmaceutics. E.g., if you have an intramuscularly injection of a nano-suspension, you might want to consider a zero order process for the release of the drug in the systemic circulation and see whether particle size impacts dissolution rate. In any case, think about the pharmaceutical plausability first before testing a covariate.

Cheers,
Rob


Van: owner-nmusers_at_globomaxnm.com [mailto:owner-nmusers_at_globomaxnm.com] Namens Jing Niu
Verzonden: zondag 25 september 2016 14:41
Aan: nmusers_at_globomaxnm.com
Onderwerp: [NMusers] covariate on transit compartment model parameters

Dear NMusers,
I am modeling long-acting injectable formulation using transit compartment model parameterized with mtt (mean transit time) and ntr (number of transit compartment). As I would like to model multiple formulations using the same structure model, adding formulation as a categorical covariate on mtt or ntr separately decreased the OFV significantly (by ~100 units). Considering mtt and ntr are correlated parameters, should I add formulation on both mtt and ntr, or adding to either one is sufficient?
Any input is greatly appreciated,
Jing

PS: I am considering the latter one, due to that the simulations with changing Ktr or ntr generated similar profiles (Fig1 c and d, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3636497/pdf/psp201314a.pdf).


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Received on Mon Sep 26 2016 - 07:11:41 EDT

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