RT Journal Article SR Electronic T1 Development and Characterisation of a Human Hepatocyte Low Intrinsic Clearance Assay for Use in Drug Discovery JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP dmd.118.081596 DO 10.1124/dmd.118.081596 A1 Paul Lancett A1 Beth Williamson A1 Patrick Barton A1 Rob J Riley YR 2018 UL http://dmd.aspetjournals.org/content/early/2018/06/07/dmd.118.081596.abstract AB Progression of new chemical entities is a multi-parametric process involving a balance of potency, ADME and safety properties. To accurately predict human pharmacokinetics and estimate human efficacious dose, the use of in vitro measures of clearance is often essential. Low metabolic clearance is often targeted to facilitate in vivo exposure and achieve appropriate half-life. Suspension primary human hepatocytes (PHH) have been successfully utilised in predictions of clearance. However, incubation times are limited, hindering the limit of quantification. The aims herein were to: evaluate the ability of a novel PHH media supplement, HepExtend™, to maintain cell function, increase culture times and define the clearance of stable compounds. Cell activity was analysed with a range of CYP and uridine 5'-diphospho-glucuronosyltransferase (UGT) substrates and the mRNA expression of drug disposition and toxicity marker genes was determined. HepExtend™ and Geltrex™ were essential to maintain cell activity and viability for 5 days (N=3 donors). In comparison to CM4000±Geltrex™, HepExtend™+Geltrex™ displayed a higher level of gene expression on day 1, particularly for the CYPs, nuclear receptors and UGTs. The novel medium, HepExtend™+Geltrex™, was robust and reproducible in generating statistically significant CLint values at 0.1 μL/min/x106 cells over a 30 h period (p <0.05); lower than previously demonstrated. Following regression correction, human hepatic in vivo clearance was predicted within 3-fold for 83% of compounds tested for three human donors, with an average fold error of 2.2. The novel PHH medium, HepExtend™, with matrix overlay offers significant improvement for determining compounds with low intrinsic clearance when compared to alternative approaches.