I'm currently running an IVIVC on five different oral formulations (2 generic Test, 1 Reference, 2 formulations used for external verification). I have in vivo PK data and in vitro dissolution data on all five formulations. When I perform the deconvolution of in vivo data, I initially input the administered dose (4 mg for each formulation) and the IV dose for UIR calculation. Now this generates a deconvoluted plot that fails to reach 100% absorption, because I haven't yet corrected the oral dose for BA (30%). At this point, should I correct all five formulations at the same exact BA-corrected dose (30% x 4 mg = 1.2 mg), or should I use individual cumulative input as generated by the deconvolution (last timepoint) for each formulation? By doing the second option, I would input different doses for each formulation, but upon recalculation of the deconvolution I would reach 100% absorption for each formulation.
What bothers me is that doing this individual correction, I get a PK profile different from the original PK data, i.e. the formulation with the steepest absorption slope and higher Cmax, would not necessarily be the most rapid absorbed formulation on the "input-corrected" deconvoluted plot...
Thanks for your input everyone,
[img/] [file name=PK.png size=54231]http://pharsight.com/extranet/media/kunena/attachments/legacy/files/PK.png[/file]