Azole antifungals and inter-individual differences in drug metabolism: the role of pharmacogenomics and precision medicine.

Introduction: Azole antifungal drugs are commonly prescribed to treat invasive fungal infections in various disease conditions. However, these drugs are substrates and inhibitors of cytochrome P450 (CYP) enzymes, UGT1A4, and P-gp. The genetic variants of CYP3A4/5, CYP2C9, CYP2C19, ABCB1, or UGT1A4 can modify the safety or effectiveness of azole antifungals.

Areas covered: This review has collated the recent advances in the pharmacogenomics of azole antifungals pertaining to their metabolism and the safety or effectiveness of their use. A literature search was performed in PubMed from inception to the 5^th of December 2022 to retrieve articles focusing on pharmacogenomics of azole antifungals.

Expert opinion: Optimizing the safety or effectiveness of most azole antifungals, excluding voriconazole, through pharmacogenomics remains largely theoretical, pending laboratory assessment in future studies. However, the ample evidence of the clinically significant pharmacogenetic impacts of voriconazole, due to the CYP2C19 genetic variability, favors clinical implementation. The inconsistencies of the pharmacogenomics-based dosing guidelines for voriconazole, from different international pharmacogenomics working groups, may hinder clinicians in assimilating and applying such pharmacogenetic information into clinical practice. Consideration of drug-drug interactions along with the pharmacogenetic effects may advance the precision medicine of azole antifungals and allow greater effectiveness in clinical practice.