An In Vitro Human Small Intestine Tissue Model for Drug Permeation Studies

 说明(申请人提供)：目前市场上大约60%的药物是口服制剂，其临床疗效关键取决于从小肠(SMI)的吸收。然而，目前可用的体外肠道模型主要依赖于不能概括小肠三维微环境的癌细胞株。同样，动物模型往往不能预测候选药物的体内人类结果。在第一阶段，我们成功地开发了一种有前景的小肠药物渗透模型，该模型基于由人SMI细胞组成的体外器官型组织。体外培养的SMI组织在组织学、跨上皮电阻和结构特征方面与自然人类组织具有良好的一致性。证明了SMI模型在药物渗透研究中的实用性。在体外，SMI通透性数据与体内人体吸收数据具有很强的相关性(R2=0.87-0.95)，而广泛使用的Caco-2细胞模型的数据预测较差(R2=0.81)。渗透性数据还表明，SMI体外组织中的外排转运体具有功能，抑制研究表明SMI组织可能有助于研究药物与药物的相互作用。体外模型的经济分析表明，与可比的啮齿动物生物利用度研究相比，该模型具有显著的优势。该项目的最终目标是产生一种经过验证的、与生物相关的器官型SMI模型，该模型预测口服药物的肠道药物吸收/生物利用度。SMI模型具有与人体相似的特性，能够测量药物的吸收、代谢和药物与药物的相互作用，是一种优于现有体外和体外方法的工具。在拟议的应用中，我们将最终确定一个药物渗透和代谢预测模型。将确定该模型的重复性，并将证明体外检测方法可移植到其他实验室。这些第二阶段目标的成功完成将为早期临床前药物筛选带来一个极其有用的模型。基于人类原代细胞的SMI组织模型将改善新药制剂的药代动力学分析，加速药物开发，降低不断增长的药物开发成本。

 DESCRIPTION (provided by applicant): Approximately 60% of currently marketed drugs are orally administered formulations whose clinical efficacy critically depends on the absorption from the small intestine (SMI). However, currently available in vitro intestinal models rely predominantly on cancer cell lines that do not recapitulate the 3D microenvironment of the small intestine. Likewise, animal models often fail short in predicting in vivo human outcomes of candidate drugs. During Phase I, we successfully developed a promising small intestine drug permeation model based on an in vitro, organotypic tissue comprised of human SMI cells. Characterization of the in vitro SMI tissues showed good correspondence to native human tissue in terms of histology, transepithelial electrical resistance, and structural features. The utility of the SMI model for drug permeation studies was demonstrated. In vitro SMI permeability data strongly correlated with in vivo human absorption data (r2 = 0.87 - 0.95) whereas data from the widely-used Caco-2 cell line model was less predictive (r2 = 0.81). Permeability data also demonstrated that efflux transporters were functional in the SMI in vitro tissue and inhibition studies showed that the SMI tissue will likely be useful to study drug-drug interactions. An economic analysis of the in vitro model showed significant advantages versus comparable rodent bioavailability studies. The ultimate goal of this project is produce a validated, biologically relevant organotypic SMI model that predicts intestinal drug absorption/bioavailability of orally administered drugs. The human in vivo-like characteristics of the SMI model and its capacity to measure drug absorption, metabolism, and drug-drug interactions make it a superior tool to existing in vitro and ex-vivo methods. In the proposed application, we will finalize a drug permeation and metabolism prediction model. Reproducibility of the model will be determined and transferability of the in vitro assay methods to other laboratories will be demonstrated. Successful completion of these Phase 2 goals will result in an extremely useful model for early preclinical drug screening. The human primary cell based SMI tissue model will improve pharmacokinetic analysis of new drug formulations, accelerate drug development, and reduce the ever- increasing development cost of drugs.