Identifying the reactive metabolites of tyrosine kinase inhibitors in a comprehensive approach: Implications for drug‐drug interactions and hepatotoxicity

Abstract

Tyrosine kinase inhibitors (TKI) are small heterocyclic molecules targeting transmembrane and cytoplasmic tyrosine kinases that have met with considerable success in clinical oncology. TKI are associated with toxicities including liver injury that may be serious and even life‐threatening. Many of them require warnings in drug labeling against liver injury, and five of them have Black Box Warning (BBW) labels. Although drug‐induced liver injury is a matter of clinical and industrial concern, little is known about the underlying mechanisms that likely involve reactive metabolites (RM). RM are electrophiles or radicals originating from the metabolic activation of particular functional groups, known as structural alerts or toxicophores. RM are able to covalently bind to proteins and macromolecules, causing cellular damage and even cell death. If the adducted protein is the enzyme involved in RM formation, time‐dependent inhibition of the enzyme—also called mechanism‐based inhibition (MBI) or inactivation—can occur and lead to pharmacokinetic drug‐drug interactions. To mitigate RM liabilities, common practice in drug development includes avoiding structural alerts and assessing RM formation via RM trapping screens with soft and hard nucleophiles (glutathione, potassium cyanide, and methoxylamine) in liver microsomes. RM‐positive derivatives are further optimized to afford drug candidates with blocked or minimized bioactivation potential. However, different structural alerts are still commonly used scaffolds in drug design, including in TKI structures. This review focuses on the current state of knowledge of the relations among TKI structures, bioactivation pathways, RM characterization, and hepatotoxicity and cytochrome P450 MBI in vitro.

Permeabilized Cryopreserved Human Hepatocytes as an Exogenous Metabolic System in a Novel Metabolism-Dependent Cytotoxicity Assay for the Evaluation of Metabolic Activation and Detoxification of Drugs Associated with Drug-Induced Liver Injuries: Results with Acetaminophen, Amiodarone, Cyclophosphamide, Ketoconazole, Nefazodone, and Troglitazone

“…Evaluation of reactive metabolite formation to minimize the risks of developing drugs with drug induced liver injuries (DILI potential) was firstly applied in Merck Research Laboratories (Evans et al, 2004) and now widely adopted in drug development. Commonly used approaches include Incubation of the chemicals in question with human liver microsomes in the presence of a trapping agent such as glutathione, followed by LC-MS/MS identification of the reactive metabolite-GSH conjugate (Ma and Chowdhury, 2012;Huang et al, 2015;Hosaka et al, 2018;Paludetto et al, 2019) as well as quantification of covalent binding to human liver microsomal proteins (Mitrea et al, 2010;Kakutani et al, 2021). However, there are concerns with the inadvertent removal of drug candidates without toxicological consequences with this approach (Obach et al, 2008;Kalgutkar and Didiuk, 2009).…”

Potential for pharmacokinetic interactions between Schisandra sphenanthera and bosutinib, but not imatinib: in vitro metabolism study combined with a physiologically‐based pharmacokinetic modelling approach

“…Conversely, it was predicted to have no effect on imatinib concentrations at steady state (Figure 4). This disparity was attributed to the mechanism‐based inactivation of CYP3A4 69 by a reactive metabolite of imatinib 70 . This leads to a lower sensitivity towards CYP3A inhibition at steady‐state, as demonstrated by a lack of clinically‐significant interaction between imatinib and ritonavir 71 .…”

Design, Synthesis, and Biological Evaluation of Pyrano[2,3-c]-pyrazole–Based RalA Inhibitors Against Hepatocellular Carcinoma

“…Hepatocellular carcinoma (HCC) is a primary liver malignancy with one of the highest mortality rates worldwide ( Jacobson et al, 2018 ; Zhou et al, 2018 ; Paludetto et al, 2019 ; Siegel et al, 2019 ). Although significant progress has been made to improve chemotherapy, transcatheter artery chemoembolization (TACE), and targeted HCC therapy, many patients still present recurrences and the development of drug resistance ( Xue et al, 2019 ; Pan et al, 2020 ; Yu et al, 2020 ).…”