{"title":"Methods for kinetic evaluation of reversible covalent inhibitors from time-dependent IC<sub>50</sub> data.","authors":"Lavleen K Mader, Jeffrey W Keillor","doi":"10.1039/d5md00050e","DOIUrl":null,"url":null,"abstract":"<p><p>Potent reversible covalent inhibitors are often slow in establishing their covalent modification equilibrium, resulting in time-dependent inhibition. While these inhibitors are commonly assessed using IC<sub>50</sub> values, there are no methods available to analyze their time-dependent IC<sub>50</sub> data to provide their inhibition (<i>K</i> <sub>i</sub> and ) and covalent modification rate (<i>k</i> <sub>5</sub> and <i>k</i> <sub>6</sub>) constants, leading to difficulty in accurately ranking drug candidates. Herein, we present an implicit equation that can estimate these constants from incubation time-dependent IC<sub>50</sub> values and a numerical modelling method, EPIC-CoRe, that can fit these kinetic parameters from pre-incubation time-dependent IC<sub>50</sub> data. The application of these new methods is demonstrated by the evaluation of a known inhibitor, saxagliptin, providing results consistent with those obtained by other known methods. This work introduces two new practical methods of evaluation for time-dependent reversible covalent inhibitors, allowing for rigorous characterization to enable the fine-tuning of their binding and reactivity.</p>","PeriodicalId":21462,"journal":{"name":"RSC medicinal chemistry","volume":" ","pages":""},"PeriodicalIF":4.1000,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11951164/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"RSC medicinal chemistry","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1039/d5md00050e","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Potent reversible covalent inhibitors are often slow in establishing their covalent modification equilibrium, resulting in time-dependent inhibition. While these inhibitors are commonly assessed using IC50 values, there are no methods available to analyze their time-dependent IC50 data to provide their inhibition (Ki and ) and covalent modification rate (k5 and k6) constants, leading to difficulty in accurately ranking drug candidates. Herein, we present an implicit equation that can estimate these constants from incubation time-dependent IC50 values and a numerical modelling method, EPIC-CoRe, that can fit these kinetic parameters from pre-incubation time-dependent IC50 data. The application of these new methods is demonstrated by the evaluation of a known inhibitor, saxagliptin, providing results consistent with those obtained by other known methods. This work introduces two new practical methods of evaluation for time-dependent reversible covalent inhibitors, allowing for rigorous characterization to enable the fine-tuning of their binding and reactivity.