Bioequivalence and Bioavailability Forum

Dear Helmut,

❝ ❝ • Subject A - had BLQ (Below limit of Quantification) for all the time points for one of Test treatment and

❝ ❝ • Subject B - had BLQ for all the time points in one of Reference treatment.

❝ ❝

❝ ❝ Can we include Subject A & B for statistical analysis

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❝ Well, the statistical model is based on \(\small{\log_{e}}\)-transformed data. You have to exclude them, since \(\small{\log_{e}(0)}\) is undefined (for nitpickers: \(\small{\lim \log_{e}(x\rightarrow 0) = -\infty}\)).

Well, indeed you can't analyse the study without excluding at least that period. NK's study is intended for the US FDA, I don't know how these guys react to such exclusions. In Europe, subject B could be excluded according to the EU BE guideline, but subject A could not as the period with all BLQ was after the test product. EU regulators will tell you that this might be due to your product and you can't exclude the data just because they don't suit you. In such a situation: you're screwed.