Multiplex Phenotyping for Systems Medicine: A One-Point Optimized Practical Sampling Strategy for Simultaneous Estimation of CYP1A2, CYP2C9, CYP2C19, and CYP2D6 Activities Using a Cocktail Approach

Abstract

Phenotyping of the CYP450 enzyme activities contributes to personalized medicine, but the past phenotyping approaches have followed a piecemeal strategy measuring single enzyme activities in vivo. A barrier to phenotyping of populations in rural and remote areas is the limited time and resources for sample collection. The CEIBA cocktail approach allows metabolic capacity estimation of multiple CYP450 enzymes in a single sample analysis, but the attendant sample collection schemes for applications in diverse global settings are yet to be optimized. The present study aimed to select an optimal matrix to simultaneously analyze CYP450 enzyme activities so as to simplify the sampling schemes in the phenotyping protocol to enhance its throughput and feasibility in native populations or in remote and underserviced geographies and social contexts. We evaluated 13 Ecuadorian healthy volunteers for CYP1A2, CYP2C9, CYP2C19, and CYP2D6 genotypes and their metabolic phenotypes, including CYP3A4, in plasma and urine after administering one reduced dose of caffeine, losartan, omeprazole, and dextromethorphan. Pharmacokinetic analyses were performed, and the correlation between AUC parent/AUC metabolite and the ratio between concentrations of probe drugs and their corresponding metabolites at timepoints ranging from 0 to 12 hours post-dose were analyzed. A single sampling timepoint, 4 hours post-dose in plasma, was identified as optimal to reflect the metabolic activity of the attendant CYP450 enzymes. This study optimizes the CEIBA multiplexed phenotyping approach and offers new ways forward for integrated drug metabolism analyses, in the pursuit of global personalized medicine applications in resource-limited regions, be they in developed or developing countries.

Can the CEIBA Cocktail Designed for Human Cytochrome P450 Enzymes be Used in the Rat for Drug Interaction Studies?

“…The respective main plasma pharmacokinetic parameters were determined and summarised in Table 1. Regarding the 3-MM, several values of concentrations below the LOQ were found in rat plasma, similarly to the phenomenon observed in humans (4,25); thus, the 3-MM was properly quantified just in few samples and, therefore, it was not possible to carry out a suitable pharmacokinetic analysis for this compound (Table 1).…”

“…Such assays involve the administration of substrates (probes) which are selectively metabolized by a given CYP isoenzyme, and the substrate/ metabolite concentration ratio, or the metabolic ratio, is calculated. Numerous cocktails are reported to phenotype humans (4,(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24), e.g., Cooperstown 5+1 (18), Karolinska (19), Sanofi-Aventis (20), Inje (21), CIME (22), Basel (23), Geneva (24), and CEIBA cocktail (4,25).…”

“…Recently, we proposed the CEIBA cocktail consisting of four probe drugs [caffeine (CAF), omeprazole (OZ), dextromethorphan (DM) and losartan (LOS)] for the simultaneous phenotyping of the five major human drug-metabolizing CYP isoenzymes (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4) in just one assay (3,4,25). Nonetheless, its potential application in the rat has never been studied.…”

Urine metabolic ratio of omeprazole in relation to CYP2C19 polymorphisms in Russian peptic ulcer patients

“…In some other studies, omeprazole concentration in urine could not be measured because of unsuitable buffer that caused omeprazole degradation in urine samples. 18 , 19 …”

“…The goal of investigators was to find optimal matrix (plasma or urine) and one time point for measuring drugs and metabolites from cocktail (caffeine, losartan, omeprazole, and dextromethorphan) to reflect the activity of CYPs. 19 Blood and urine samples were taken for 12 hours period from 13 healthy volunteers for CYP2C19 phenotyping. As for plasma metabolic ratio (omeprazole AUC/5-hydroxyomeprazole AUC), optimal time point was 3–12 hours after 20 mg omeprazole single dose.…”