cyclosporin a; area under the curve; bioequivalence; drug absorption; drug bioavailability; drug distribution; drug formulation; drug transformation; gastrointestinal absorption; letter; priority journal; Aryl Hydrocarbon Hydroxylases; Cyclosporine; Cytochrome P-450 CYP3A; Cytochrome P-450 Enzyme System; Humans; Oxidoreductases, N-Demethylating; Therapeutic Equivalency