Moulton Richard D, Ruterbories Kenneth J, Bedwell David W, Mohutsky Michael A
Eli Lilly and Company, Indianapolis, Indiana (R.D.M., K.J.R., D.W.B., M.A.M.)
Eli Lilly and Company, Indianapolis, Indiana (R.D.M., K.J.R., D.W.B., M.A.M.).
Drug Metab Dispos. 2015 May;43(5):756-61. doi: 10.1124/dmd.114.062893. Epub 2015 Mar 9.
To characterize the hydrolysis of the peptide prodrug pomaglumetad methionil (LY2140023; (1R,4S,5S,6S)-4-(L-methionylamino)-2-thiabicyclo[3.1.0]hexane-4,6-dicarboxylic acid 2,2-dioxide), to the active drug LY404039 [(1R,4S,5S,6S)-4-amino-2-thiabicyclo[3.1.0]hexane-4,6-dicarboxylic acid 2,2-dioxide], a series of in vitro studies were performed in various matrices, including human intestinal, liver, kidney homogenate, and human plasma. The studies were performed to determine the tissue(s) and enzyme(s) responsible for the conversion of the prodrug to the active molecule. This could enable an assessment of the risk for drug interactions, an evaluation of pharmacogenomic implications, as well as the development of a Physiologically Based Pharmacokinetic (PBPK) model for formation of the active drug. Of the matrices examined, hydrolysis of pomaglumetad methionil was observed in intestinal and kidney homogenate preparations and plasma, but not in liver homogenate. Clearance values calculated after applying standard scaling factors suggest the intestine and kidney as primary sites of hydrolysis. Studies with peptidase inhibitors were performed in an attempt to identify the enzyme(s) catalyzing the conversion. Near complete inhibition of LY404039 formation was observed in intestinal and kidney homogenate and human plasma with the selective dehydropeptidase1 (DPEP1) inhibitor cilastatin. Human recombinant DPEP1 was expressed and shown to catalyze the hydrolysis, which was completely inhibited by cilastatin. These studies demonstrate pomaglumetad methionil can be converted to LY404039 via one or multiple enzymes completely inhibited by cilastatin, likely DPEP1, in plasma, the intestine, and the kidney, with the plasma and kidney involved in the clearance of the circulating prodrug. These experiments define a strategy for the characterization of enzymes responsible for the metabolism of other peptide-like compounds.
为了表征肽前药波马格列他甲硫氨酸（LY2140023；(1R,4S,5S,6S)-4-(L-甲硫氨酰氨基)-2-硫杂双环[3.1.0]己烷-4,6-二甲酸 2,2-二氧化物）水解为活性药物LY404039 [(1R,4S,5S,6S)-4-氨基-2-硫杂双环[3.1.0]己烷-4,6-二甲酸 2,2-二氧化物]的过程，在包括人肠、肝、肾匀浆和人血浆在内的各种基质中进行了一系列体外研究。进行这些研究是为了确定负责将前药转化为活性分子的组织和酶。这有助于评估药物相互作用的风险、评估药物基因组学影响，以及开发用于活性药物形成的基于生理的药代动力学（PBPK）模型。在所检查的基质中，在肠和肾匀浆制剂以及血浆中观察到波马格列他甲硫氨酸的水解，但在肝匀浆中未观察到。应用标准比例因子后计算的清除率值表明肠和肾是水解的主要部位。进行了肽酶抑制剂研究，试图鉴定催化转化的酶。在肠和肾匀浆以及人血浆中，使用选择性脱氢肽酶1（DPEP1）抑制剂西司他丁观察到LY404039形成几乎完全受到抑制。表达了人重组DPEP1并证明其催化水解，而西司他丁可完全抑制该水解。这些研究表明，波马格列他甲硫氨酸可通过一种或多种被西司他丁（可能是DPEP1）完全抑制的酶在血浆、肠和肾中转化为LY404039，血浆和肾参与循环前药的清除。这些实验确定了一种表征负责其他肽类化合物代谢的酶的策略。
