Bioequivalence and Bioavailability Forum

Dear Vidya!

❝ Dear Vienna,

Funny. My name is Helmut (see my signature and my profile); Vienna is the town I'm living in.

❝ Drug was Flurbiprofen, as far as I know it doesn't have other active

❝ metabolite.

I didn't talk about active metabolites, but metabolism in general. Flurbiprofen is hydroxilated by CYP2C9; polymorphism is documented. Maybe the subject was depressed staying at the clinical site and took St. John's wort (an inducer of CYP2C9).

❝ During analysis, for rest of the subjects concentration were detected

❝ except one where the concentration was nil for both the periods.

Again: please delete 'nil' from your (bioanalytical) vocabulary.

❝ But my confusion is that as subject was dosed but concentration is nil,

❝ what will be the possible reason and how to report the same.

Simon's answer is reasonable. Some volunteers are quite good in hiding a drug during a 'mouth check'. Was this a 'new' volunteer or had you a similar experience with him/her in previous studies?
Concerning reporting: As already said, report the finding as it is. Of course nothing to calculate...