Racemate vs. enantiomer? [Regulatives / Guidelines]

posted by Relaxation  – Germany, 2018-01-18 11:37 (1896 d 21:14 ago) – Posting: # 18205
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Hi everybody.

❝ Other opinions are welcome.

Then I just have to add some quick thoughts. Taking the risk of having misunderstood the post.
I am not sure I agree with the interpretation here:

❝ One of the prerequisites in BE is that same molar doses of the active ingredient are administered. If the enantiomeric ratio* of the reference is 1:1, IMHO, you would have to administer twice the dose of the test and use a chiral method (assessing only the active enantiomer for BE).

I would focus here on the wording "active ingredient". Either both enantiomers are active, then you need to administer both anyway or have some long discussions on substituting one enatiomer with the other or whatever. I cannot think of an example, but that's my theory.
If there is only one active enantiomer, I would guess the other one is simply an inactive ingredient.
So in conclusion, proposing 50 mg of the pure active enantiomer as a generic to a product containing 100 mg of the 1:1 racemate would work for me.
But I am not an assessor and I have no example. Got involved in a discussion on dexibuprofen briefly, but there it is more complicated due to interconversion and still some discussion of a contribution of both enantiomers to efficacy.

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