Pharmacokinetics, Dynamics and Metabolism, Pfizer Inc., Eastern Point Road, Groton, CT 06340, USA.
Drug Metab Dispos. 2012 Sep;40(9):1860-5. doi: 10.1124/dmd.112.046425. Epub 2012 May 29.
A novel relay method has been developed using cryopreserved human hepatocytes to measure intrinsic clearance of low-clearance compounds. The relay method involved transferring the supernatant from hepatocyte incubations to freshly thawed hepatocytes at the end of the 4-h incubation to prolong the exposure time to active enzymes in hepatocytes. An accumulative incubation time of 20 h or longer in hepatoctyes can be achieved using the method. The relay method was validated using seven commercial drugs (diazepam, disopyramide, theophylline, timolol, tolbutamide, S-warfarin, and zolmitriptan) that were metabolized by various cytochrome P450s with low human in vivo intrinsic clearance at approximately 2 to 15 ml · min⁻¹ · kg⁻¹. The results showed that the relay method produced excellent predictions of human in vivo clearance. The difference between in vitro and in vivo intrinsic clearance was within 2-fold for most compounds, which is similar to the standard prediction accuracy for moderate to high clearance compounds using hepatocytes. The relay method is a straightforward, relatively low cost, and easy-to-use new tool to address the challenges of low clearance in drug discovery and development.
一种新的接力方法已经被开发出来，使用冷冻保存的人肝细胞来测量低清除率化合物的内在清除率。接力方法涉及在 4 小时孵育结束时将肝细胞孵育的上清液转移到新解冻的肝细胞中，以延长肝细胞中活性酶的暴露时间。使用该方法可以实现 20 小时或更长时间的累积孵育时间。该接力方法使用七种商业药物（地西泮、双异丙吡胺、茶碱、噻吗洛尔、甲苯磺丁脲、S-华法林和佐米曲坦）进行了验证，这些药物被各种细胞色素 P450 代谢，其在人体内的内在清除率较低，约为 2 至 15 ml·min⁻¹·kg⁻¹。结果表明，接力方法对人体体内清除率的预测效果非常好。对于大多数化合物，体外和体内内在清除率之间的差异在 2 倍以内，与使用肝细胞对中等到高清除率化合物的标准预测精度相似。接力方法是一种简单、相对低成本且易于使用的新工具，可以解决药物发现和开发中低清除率的挑战。
