Racemate vs. enantiomer? [Regulatives / Guidelines]

posted by Helmut Homepage – Vienna, Austria, 2018-01-17 14:40 (1347 d 14:50 ago) – Posting: # 18190
Views: 2,707

Hi Christian,

» A Clinical study is going to be with an enantiomer (not racemate).

Are you talking about bioequivalence?

» The enantiomers exhibit different pharmacodynamic characteristics but only the active enantiomer is going to be in the formulation.
» There is no in-vivo interconversion.
» The reference standard is going to be the enantiomer (not racemate).

» Is a chiral method required? Can I go with a simple achiral method?

Which regulation? F.i. the FDA’s requirements concerning chiral methods are diametral to the EMA’s (see also here and there). Can’t find anything in the Mexican one.
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).

Other opinions are welcome.

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Helmut Schütz

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