Utility of spherical human liver microtissues for prediction of clinical drug-induced liver injury

Abstract

Drug-induced liver injury (DILI) continues to be a major source of clinical attrition, precautionary warnings, and post-market withdrawal of drugs. Accordingly, there is a need for more predictive tools to assess hepatotoxicity risk in drug discovery. Three-dimensional (3D) spheroid hepatic cultures have emerged as promising tools to assess mechanisms of hepatotoxicity, as they demonstrate enhanced liver phenotype, metabolic activity, and stability in culture not attainable with conventional two-dimensional hepatic models. Increased sensitivity of these models to drug-induced cytotoxicity has been demonstrated with relatively small panels of hepatotoxicants. However, a comprehensive evaluation of these models is lacking. Here, the predictive value of 3D human liver microtissues (hLiMT) to identify known hepatotoxicants using a panel of 110 drugs with and without clinical DILI has been assessed in comparison to plated two-dimensional primary human hepatocytes (PHH). Compounds were treated long-term (14 days) in hLiMT and acutely (2 days) in PHH to assess drug-induced cytotoxicity over an 8-point concentration range to generate IC50 values. Regardless of comparing IC50 values or exposure-corrected margin of safety values, hLiMT demonstrated increased sensitivity in identifying known hepatotoxicants than PHH, while specificity was consistent across both assays. In addition, hLiMT out performed PHH in correctly classifying hepatotoxicants from different pharmacological classes of molecules. The hLiMT demonstrated sufficient capability to warrant exploratory liver injury biomarker investigation (miR-122, HMGB1, α-GST) in the cell-culture media. Taken together, this study represents the most comprehensive evaluation of 3D spheroid hepatic cultures up to now and supports their utility for hepatotoxicity risk assessment in drug discovery.Electronic supplementary materialThe online version of this article (doi:10.1007/s00204-017-2002-1) contains supplementary material, which is available to authorized users.

Mechanistic investigations of the liver toxicity of the free fatty acid receptor 1 agonist fasiglifam (TAK875) and its primary metabolites

“…Richert et al postulated that exposure periods longer than 72 hours in human hepatocytes do not increase the DILI‐prediction rate compared with shorter exposure times. Contrary to this Proctor et al recently reported higher predictivity of liver toxicants by 3D hLiMT (14‐day treatment) vs plated D2 primary human hepatocytes (48h‐treatment). In contrast to our cytotoxicity results, Otieno et al described that TAK875 1 is not cytotoxic in hepatocytes and HepG2 cells (data were not shown) following incubation of 100 µM for 72 hours.…”

3D Primary Hepatocyte Culture Systems for Analyses of Liver Diseases, Drug Metabolism, and Toxicity: Emerging Culture Paradigms and Applications

“…Two systematic benchmarking studies for hepatotoxicity tests have been published in PHH spheroids to date. Proctor et al used a commercial proprietary model to test the toxicity of 110 drugs (69 DILI‐positive and 41 DILI‐negative) during 14 days of repeated exposures using the InSphero model and reported overall sensitivity and specificity of 59% and 80%, respectively. In contrast, we used chemically defined media and ULA 3D PHH spheroids to expose a panel of 123 drugs (70 DILI‐positive and 53 DILI‐negative), correctly predicting the hepatotoxicity of 48 out of 70 compounds (sensitivity = 69%) without a single false‐positive result (specificity = 100%; Figure A) .…”

Highlight report: prediction of drug induced liver injury (DILI) with human hepatocytes in vitro

“…Therefore, the risk of human DILI has been massively underestimated by the in vitro system. Similar problems exist for the category 1 compounds dantrolene, methotrexate, stavudine and trovafloxacin (Proctor et al 2017;Table S-3, S3h LiMT data). It is interesting to note that cytotoxicity allows a good prediction of human blood concentrations associated with an increased risk of DILI for some compounds, while it leads to a massive underestimation of other severe DILI compounds.…”

“…However, a comprehensive study including a sufficiently large number of compounds for validation of these endpoints is not yet available. The merit of the present study (Proctor et al 2017) is that it delivers a comprehensive cytotoxicity database, which clearly demonstrates that cytotoxicity alone is not sufficient to predict human DILI. In conclusion, the hunt for an accurate in vitro system quantitatively predicting human hepatotoxicity has only just begun.…”