Rapid multichannel fluorescent probe assay for CYP450 inhibition screening and drug interaction monitoring

Cytochrome P450 (CYP450) inhibition induced drug interactions (DDIs) are a primary cause of adverse drug reactions (ADRs). The rapid identification of CYP450 inhibitors is an important method for reducing potential ADRs. However, the existing methods are often intricate and time consuming, making them difficult to use for high-throughput rapid monitoring. Based on the specificity of CYP450 to the catalysis of different fluorescent substrate probes, an assay was developed to monitor the activity of six CYP450 isoforms simultaneously. The production rate of fluorescent metabolites characterized CYP450 activity. Method specificity was evaluated using inhibitors recommended by the FDA Guidelines for Drug Interaction Studies. We screened 28 clinically utilized medications for inhibition of CYP450 and evaluated the potential interaction by comparing inhibition constants ( K i ) and maximum plasma concentration (C max ). The analysis of the positive inhibitors using this method suggests that it allows for quick screening and identification of CYP450 inhibitors. Six drugs, including latoxefin, diclofenac, erythromycin lactate, labetalol, cimetidine, and droperidol, showed an interaction risk. The three isoforms of the CYP1A2, CYP3A4 and CYP3A5 metabolizing enzyme mediate a greater number of interactions, which should be specifically monitored in clinical applications. The established method permits rapid screening for inhibiting CYP1A2, CYP2E1, CYP2B6, CYP2A6, CYP3A4 and CYP3A5 with simple, stable, inexpensive, and high-throughput. This method will provide technical support for rapid discovery of clinical CYP450 inhibitors and risk avoidance of drug combination.