Bioequivalence and Bioavailability Forum

Hi,

Dont laugh....

I received a single dose conc-time dataset from a 50 subject PK study. The compound is endogenous so there was pre-dose conc in every subject. Samples were collection from pre-dose and up to 12 hours at predetermined intervals. I reviewed the conc-time dataset prior to dumping it into Phoenix to carry out the NCA analysis.

Issue: One subject has pre-dose conc being greater than the highest conc in post-dose. The PK profile is legit (conc increased, reached peak, and decreased overtime). Phoenix's NCA identified pre-dose as the Cmax with Tmax = 0 (of course!).

Question: Is there a way to set up NCA in Phoenix such that the routine will exclude the pre-dose conc from being identified as Cmax? I goofed around and set up NCA to carry out the analysis as a mutiple-dose/steady state study but I still get the same result.

Thx
J