Bioequivalence and Bioavailability Forum

Dear d_labes,

❝ read the Section again.

Did many times, hence my question

❝ Imagine for example there is no reference product of 50 µg content, no one produces the 50 µg formulation any longer, but only one with 60 µg. And the patient is optimally prescribed a dose of 50 µg. Having such a formulation with 50 µg is a benefit for the patient, I think.

That is an interesting aspect and not one that I ever came across. In EU this would qualify as a 10.3 and in the US as a 505(b)(2), but be that as it may.
Would your example really make T(50) bioequivalent to R(60) (after all you are saying T(50) is a better treatment option than R(60)), or would you just call T(50) approvable?

It makes for an interesting discussion, philosophically at least, when we use your example in conjunction with section 1.1: "Two medicinal products containing the same active substance are considered bioequivalent if they are pharmaceutically equivalent or pharmaceutical alternatives and their bioavailabilities (rate and extent) after administration in the same molar dose lie within acceptable predefined limits."
One one hand you can say you are definitely not testing the same molar dose (whether actual or by intention) so they can't be BE. On the other hand you can say the potency correction adjusts for exactly that discrepancy.

Anyhow, the intention with section 4.1.8, I think, was to pave the way forward for a case where e.g. the Test has a potency of 104% and the Ref has a potency of 95% of the (identical) label claim etc. I believe so due to the wording that mentions the difficulty of finding a matching reference batch (not a matching reference strength). As always I could be wrong. I hope others will chime in.