Bioequivalence and Bioavailability Forum

Hi,

Would someone give me some idea on the following case?

It sounds a bit simple but what is the proper way to determine Kel from the elimination phase, based on noncompartmental analysis, if the last measurable timepoint has a higher concentration than the adjacent timepoint? Should Kel be labelled as "Undefined"? Some CROs would say "Undefined" but there are others who would determine Kel as long as the linear regression result based on the timepoints involved (at least 3) is acceptable.

Thanks

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Edit: Category changed. [Helmut]