Background:
Chiral safety, especially chiral drug inversion in vivo, is the top priority of
current scientific research. Medicine researchers and pharmacists often ignore that one enantiomer will
be converted or partially converted to another enantiomer when it is ingested in vivo. So that, in the
context that more than 50% of the listed drugs are chiral drugs, it is necessary and important to pay attention
to the inversion of chiral drugs.
Methods:
The metabolic and stereoselective pharmacokinetic characteristics of seven chiral drugs with
one chiral center in the hydroxy group were reviewed in vivo and in vitro including the possible chiral
inversion of each drug enantiomer. These seven drugs include (S)-Mandelic acid, RS-8359, Tramadol,
Venlafaxine, Carvedilol, Fluoxetine and Metoprolol.
Results:
The differences in stereoselective pharmacokinetics could be found for all the seven chiral
drugs, since R and S isomers often exhibit different PK and PD properties. However, not every drug
has shown the properties of one direction or two direction chiral inversion. For chiral hydroxyl group
drugs, the redox enzyme system may be one of the key factors for chiral inversion in vivo.
Conclusion:
In vitro and in vivo chiral inversion is a very complex problem and may occur during every
process of ADME. Nowadays, research on chiral metabolism in the liver has the most attention,
while neglecting the chiral transformation of other processes. Our review may provide the basis for the
drug R&D and the safety of drugs in clinical therapy.
Quiral Inversion of Ibuprofen after an Oral Administration Under Complete Fasting and Fed Conditions in Caucasian Healthy Subjects
