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Published on: March 14, 2014
Itraconazole and clarithromycin as ketoconazole alternatives for clinical CYP3A inhibition studies
A B Ke1, M J Zamek-Gliszczynski1, J W Higgins1
1Drug Disposition, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana, USA.
Abstract:
High-dose ketoconazole (400 mg q.d. for ≥5 days) has been the gold-standard strong cytochrome P450 3A (CYP3A) inhibitor in drug development drug-drug interaction (DDI) studies. In 2013, the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) advised against using this ketoconazole regimen following review of clinical safety reports. We systematically evaluated 19 strong CYP3A inhibitors from regulatory guidances and a literature database to identify itraconazole (200 mg b.i.d. on day 1, q.d. on days 2-6) and clarithromycin (500 mg b.i.d. for 7 days) as acceptable ketoconazole alternatives.
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