Complex sentence: Single-enantiomer drugs are separately patentable from the racemic mixture.both enantiomers are active, or one may be active and separating the mixture has no objective benefits, but extends the drug's patentability.
Split into simpler sentences: Single-enantiomer drugs are separately patentable from the racemic mixture. Or, it may be that only one is active, in which case separating the mixture has no objective benefits, but extends the drug's patentability.