Development of an assay using 4-trifluoromethylumbelliferyl as a marker substrate for assessment of drug-drug interactions to multiple isoforms of UDP-glucuronosyltransferases.

Glucuronidation is catalyzed by UDP-glucuronosyltransferases (UGTs) and is one of the most important pathways for elimination of xenobiotics. The aim of the present study was to develop an in vitro assay for assessment of drug-drug interactions related to UGTs applicable to early drug discovery. 4-Trifluoromethylumbelliferyl was tested as a marker substrate for six human recombinant expressed UGT isoforms: 1A1, 1A3, 1A4, 1A6, 1A9, and 2B7.