Simultaneous Assessment of Clearance, Metabolism, Induction, and Drug-Drug Interaction Potential Using a Long-Term In Vitro Liver Model for a Novel Hepatitis B Virus Inhibitor.

Long-term in vitro liver models are now widely explored for human hepatic metabolic clearance prediction, enzyme phenotyping, cross-species metabolism, comparison of low clearance drugs, and induction studies. Here, we present studies using a long-term liver model, which show how metabolism and active transport, drug-drug interactions, and enzyme induction in healthy and diseased states, such as hepatitis B virus (HBV) infection, may be assessed in a single test system to enable effective data integration for physiologically based pharmacokinetic (PBPK) modeling. The approach is exemplified in the case of (3S)-4-[[(4R)-4-(2-Chloro-4-fluorophenyl)-5-methoxycarbonyl-2-thiazol-2-yl-1,4-dihydropyrimidin-6-yl]methyl]morpholine-3-carboxylic acid RO6889678, a novel inhibitor of HBV with a complex absorption, distribution, metabolism, and excretion (ADME) profile. RO6889678 showed an intracellular enrichment of 78-fold in hepatocytes, with an apparent intrinsic clearance of 5.2 µl/min per mg protein and uptake and biliary clearances of 2.6 and 1.6 µl/min per mg protein, respectively. When apparent intrinsic clearance was incorporated into a PBPK model, the simulated oral human profiles were in good agreement with observed data at low doses but were underestimated at high doses due to unexpected overproportional increases in exposure with dose. In addition, the induction potential of RO6889678 on cytochrome P450 (P450) enzymes and transporters at steady state was assessed and cotreatment with ritonavir revealed a complex drug-drug interaction with concurrent P450 inhibition and moderate UDP-glucuronosyltransferase induction. Furthermore, we report on the first evaluation of in vitro pharmacokinetics studies using HBV-infected HepatoPac cocultures. Thus, long-term liver models have great potential as translational research tools exploring pharmacokinetics of novel drugs in vitro in health and disease.

Perceived stress and psychosis: The effect of perceived stress on psychotic-like experiences in a community sample of adolescents.

AIMS: Psychotic-like experiences (PLE) are sub-threshold, non-clinical forms of psychosis which can place an individual at greater risk of development of a psychotic disorder. Subtypes of PLE have also been shown to exist (bizarre experiences, persecutory ideation, perceptual abnormalities and magical thinking). Perceived stress relates to how two individuals may deal with the same objectively stressful event in different ways. The objective of our study was to investigate the extent to which perceived stress is associated with PLE in a community sample of adolescents, whether certain subtypes of PLE correlate more with perceived stress than others and to explore the role of depression with these associations. METHODS: A total of 655 students completed the community assessment of psychic experiences (CAPE) and perceived stress scale (PSS). Pearson's correlation was used to investigate the relationship between PSS and CAPE and also between perceived stress and the four subtypes of PLE. Regression then explored the effect of perceived stress on PLE when accounting for depressive symptomatology. RESULTS: Positive correlation was found between PSS and total CAPE (r = 0.405, P = 0.000). Positive significant correlation was also found between PSS and each subtype of PLE, with persecutory ideation correlating the strongest and magical thinking the least. Perceived stress was significantly associated with PLE even after adjusting for depression. CONCLUSIONS: We recommend that more regular screening of perceived stress in adolescent populations could lead to earlier recognition of PLE. Early treatment has shown to reduce rates of transition to psychosis, and so could benefit our adolescent community in the future.