Effect of antifungal drugs on cytochrome P450 (CYP) 2C9, CYP2C19, and CYP3A4 activities in human liver microsomes.

Article Details

Citation

Niwa T, Shiraga T, Takagi A

Effect of antifungal drugs on cytochrome P450 (CYP) 2C9, CYP2C19, and CYP3A4 activities in human liver microsomes.

Biol Pharm Bull. 2005 Sep;28(9):1805-8.

PubMed ID
16141567 [ View in PubMed
]
Abstract

The effects of five antifungal drugs, fluconazole, itraconazole, micafungin, miconazole, and voriconazole, on cytochrome P450 (CYP) 2C9-mediated tolbutamide hydroxylation, CYP2C19-mediated S-mephenytoin 4'-hydroxylation, and CYP3A4-mediated nifedipine oxidation activities in human liver microsomes were compared. In addition, the effects of preincubation were estimated to investigate the mechanism-based inhibition. The IC50 value against tolbutamide hydroxylation was the lowest for miconazole (2.0 microM), followed by voriconazole (8.4 microM) and fluconazole (30.3 microM). Similarly, the IC50 value against S-mephenytoin 4'-hydroxylation was the lowest for miconazole (0.33 microM), followed by voriconazole (8.7 microM) and fluconazole (12.3 microM). On the other hand, micafungin at a concentration of 10 or 25 microM neither inhibited nor stimulated tolbutamide hydroxylation and S-mephenytoin 4'-hydroxylation, and the IC50 values for itraconazole against these were greater than 10 microM. These results suggest that miconazole is the strongest inhibitor of CYP2C9 and CYP2C19, followed by voriconazole and fluconazole, whereas micafungin would not cause clinically significant interactions with other drugs that are metabolized by CYP2C9 or CYP2C19 via the inhibition of metabolism. The IC50 value of voriconazole against nifedipine oxidation was comparable with that of fluconazole and micafungin and higher than that of itraconazole and miconazole. The stimulation of the inhibition of CYP2C9-, CYP2C19-, or CYP3A4-mediated reactions by 15-min preincubation was not observed for any of the antifungal drugs, suggesting that these drugs are not mechanism-based inhibitors.

DrugBank Data that Cites this Article

Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
FluconazoleCytochrome P450 2C19ProteinHumans
Unknown
Inhibitor
Details
FluconazoleCytochrome P450 2C9ProteinHumans
Unknown
Inhibitor
Details
FluconazoleCytochrome P450 3A4ProteinHumans
Unknown
Inhibitor
Details
ItraconazoleCytochrome P450 3A4ProteinHumans
No
Substrate
Inhibitor
Details
MiconazoleCytochrome P450 2C19ProteinHumans
Unknown
Inhibitor
Details
MiconazoleCytochrome P450 2C9ProteinHumans
Unknown
Inhibitor
Details
VoriconazoleCytochrome P450 2C9ProteinHumans
Unknown
Substrate
Inhibitor
Details
Drug Interactions
DrugsInteraction
Aceclofenac
Voriconazole
The serum concentration of Aceclofenac can be increased when it is combined with Voriconazole.
Acemetacin
Voriconazole
The serum concentration of Acemetacin can be increased when it is combined with Voriconazole.
Acetohexamide
Miconazole
The serum concentration of Acetohexamide can be increased when it is combined with Miconazole.
Acetohexamide
Voriconazole
The serum concentration of Acetohexamide can be increased when it is combined with Voriconazole.
Acetylsalicylic acid
Voriconazole
The serum concentration of Acetylsalicylic acid can be increased when it is combined with Voriconazole.