C/EBP-beta PEPTIDES FOR THE TREATMENT OF LIVER INJURY AND FIBROSIS

描述(申请人提供)：肝星状细胞(HSC)的激活导致各种原因的慢性肝病的肝纤维化的发展，值得注意的是，通过凋亡清除HSC可能有助于肝损伤的恢复和肝纤维化的逆转。肝纤维化专家一致认为，抑制或逆转HS激活(治疗靶点)是治疗肝纤维化的关键。尽管我们在临床前研究中清楚地记录了持续的肝损伤，但肝纤维化的消退和肝纤维化的缺乏都被认为是慢性肝病和肝纤维化患者的重要临床目标。最后，阻止肝纤维化的进展将减少这些患者的原发性肝癌的发展，因为大多数肝细胞癌发生在肝硬变。我们研究和开发Ac-KAVD-CHO相关肽类物质的基础如下：i)非磷酸化的C/EBP？-Ala217转基因基因可阻止内源性C/EBP？的磷酸化，并激活caspase 8，从而在其激活时导致HSC凋亡，从而阻止进展和诱导退行性肝纤维化；ii)这些作用既不需要反式激活，也不需要亮氨酸拉链结构域；以及iii]含有C/EBP的RSK磷酸受体结构域的细胞绝对四肽足以复制这些作用。我们使用模拟合成创建了一个库，以改进人类使用的潜在陷阱；ii]在 分步分析选择最安全和最有效的多肽(包括激活的原代人类HSC的凋亡分析；无细胞caspase 8激活的分析；急性肝损伤/纤维化模型；高分化的原代人类肝细胞培养和小鼠的毒理学分析)。我们已经开发了有效的抗纤维化化合物，在临床试验中预期免疫原性降低，稳定性和生物利用度提高。建议的化合物显着抑制人和小鼠肝星状细胞在培养和体内的激活，在临床前肝纤维化模型和减轻肝损伤。在包括毒理学基因组学在内的初步毒理学研究中，这些化合物对高分化的肝细胞和小鼠没有毒性，至少是治疗剂量的100倍。这项研究拟完成的目标包括：小鼠模型的慢性肝纤维化分析；药代动力学；体外ADMET研究：代谢稳定性；CYP-450抑制；探索性毒理学；剂量递增研究和重复剂量范围寻找毒性研究。目前还没有治疗或预防肝纤维化的药物。完成建议化合物的这些任务将使我们能够继续进行肝纤维化患者的第二阶段STTR和临床开发。

DESCRIPTION (provided by applicant): Activation of hepatic stellate cells (HSC) is responsible for the development of liver fibrosis in chronic liver diseases of all causes and remarkably, HSC clearance by apoptosis may allow recovery from liver injury and reversal of liver fibrosis. There is full agreement among liver fibrosis experts that inhibiting o reversing HS activation (the therapeutic target) is critical for the treatment of liver fibrosis. Both regressio of liver fibrosis as well as lack of progression of liver fibrosis, in spite of continued liver injury as we clearly documented in our pre-clinical studies, are considered important clinical targets for patients with chronic liver disease and liver fibrosis. Finally, blocking the progression of liver fibrosis would decrease development of primary liver cancer in these patients since the majority of hepatocellular carcinomas arise in cirrhotic livers. The basis for our Research and Development of the Ac-KAVD-CHO related peptoids are the following: i] that the nonphosphorylatable C/EBP¿-Ala217 transgene prevents phosphorylation of endogenous C/EBP¿, and activates caspase 8 resulting in apoptosis of HSC upon their activation, preventing progression and inducing regression liver fibrosis; ii] that neither the transactivation nor the leucine zipper domains are required for these effects; and iii] that a cell permeant tetrapeptide containing the RSK phosphoacceptor domain of C/EBP¿ is sufficient to replicate these effects . We created a library using analog synthesis to improve potential pitfalls for human use; ii] use in a step-wise manner assays to select the safest and most efficient peptides (including apoptosis assays in activated primary human HSC; cell-free caspase 8 activation assays; acute liver injury/fibrogenesis models; toxicology assays in highly differentiated, primary human hepatocyte cultures and mice). We have developed effective antifibrotic compounds with expected decreased immunogenicity and improved stability and bioavailability during clinical trials. The proposed compounds markedly inhibit activation of human and mouse hepatic stellate cells in culture and in vivo in preclinical models of liver fibrosis and decreased liver injury. These compounds were not toxic in the preliminary toxicology studies, including toxicogenomics, to highly differentiated hepatocytes and mice at least at 100-fold the therapeutic dose. The aims that are proposed for completion by this STTR are: Chronic liver fibrogenesis assays in mouse models; Pharmacokinetics; In Vitro ADMET Studies :Metabolic stability; CYP-450 Inhibition; and Exploratory Toxicology; Dose Escalation Study and Repeat-Dose Range-finding Toxicity Study. There is no medication for the treatment or prevention of liver fibrosis. Completion of these tasks for the proposed compounds will allow us proceeding with a Phase-2 STTR and clinical development in patients with liver fibrosis.