Systemic AA Amyloidosis Inhibitors

描述(申请人提供)：系统性AA淀粉样变性的特征是含有AA淀粉样蛋白的不溶性纤维沉积在全身不同的器官中积聚，包括心、肾、肝、脾、肺、皮肤和胃肠道，由此这种淀粉样纤维堆积导致明显的器官功能障碍。系统性AA淀粉样变性主要与慢性炎症性疾病有关，包括类风湿性关节炎、骨髓炎、强直性脊柱炎、炎症性碗病、结核病、麻风病、霍奇金氏病、肾细胞癌和家族性地中海热。全身器官中纤维状AA淀粉样蛋白沉积的后果通常对患者是致命的，大多数患者在3-7年内因肾脏或心力衰竭而死亡。目前尚无有效的治疗AA淀粉样变性的方法，目前美国约有10万例AA淀粉样变性患者急需新的治疗方法。在我们完成的第一阶段SBIR研究中，我们设计、合成和测试了我们自己的独特的小分子化合物库(代表新的化学实体)，用于在体外和体内抑制AA淀粉样变性。使用多种体外筛选方法来鉴定特定的AA淀粉样变性有效抑制剂，我们发现我们的一些小分子化合物在体外显著干扰/抑制SAA/AA淀粉样蛋白纤维。利用实验性AA淀粉样变性的相关动物模型，我们现在已经确定了两种先导化合物(即PTI-19和51)，它们在口服后能显著抑制组织(即脾、肝和肾)中AA淀粉样蛋白的沉积，其抑制作用为50-60%。PTI-19和51代表新的化学实体，我们为重复生产这些化合物而建立的合成路线显示了仅由一种化合物和一种立体异构体组成的纯产品(&gt；98%纯度)[(通过详细分析确定，包括高效液相/质谱学、1H-核磁共振、13C-核磁共振、DEPT和X射线结晶学(对于PTI-19)]。这些研究表明，这些小分子先导化合物在开发治疗系统性AA淀粉样变性的新的有效治疗方法方面显示出巨大的前景，并值得进一步研究，如本项目第二阶段SBIR所述。在拟议的第二阶段研究中，我们将与两位世界级的有机化学家合作，优化、测试和进一步开发这些小分子化合物(包括我们的2种先导化合物)，我们预计这些小分子化合物将抑制/延缓和清除人体内聚集/纤维状AA淀粉样沉积。针对人类AA淀粉样纤维的体外测试将包括新设计的类似物，这些类似物针对口服生物利用度和增强的PK特性进行了优化，同时保持了无毒性和强大的疗效。将使用1H-核磁共振、13C-核磁共振和DEPT确定合成的每个最终产品和可能存在的立体异构体的存在。X射线结晶学还将用于核磁共振无法完全验证立体化学绝对确定的有前途的先导化合物。口服给药以及预防、减少和清除系统器官中淀粉样蛋白沉积的时间依赖性疗效将使用两个实验性的AA淀粉样蛋白小鼠模型进行评估。PK和毒性研究将帮助我们优化一种新的小分子化合物(及其支持物)，该化合物将被开发用于人类临床试验和商业化，并有望成为系统性AA淀粉样变性和相关疾病的新疗法。公共卫生相关性：系统性AA淀粉样变性通常是一种致命的疾病，其特征是全身纤维状淀粉样蛋白沉积，导致器官功能障碍，最终在3-7年内死亡(由于肾脏和/或心力衰竭)。我们设计并发现了新的小分子化合物，在模拟人类疾病的相关动物模型中，有效地减少/抑制器官中淀粉样蛋白的沉积。在这个项目中，我们打算开发一种新药(和备用药物)，用于有效治疗美国约100,000例系统性淀粉样变性患者，目前尚无真正的治疗方法。

DESCRIPTION (provided by applicant): Systemic AA Amyloidosis is characterized by the accumulation of insoluble fibril deposits containing the AA amyloid protein in different organs throughout the body including heart, kidney, liver, spleen, lungs, skin and gastrointestinal tract, whereby such amyloid fibril accumulation leads to pronounced organ dysfunction. Systemic AA amyloidosis is associated mostly with chronic inflammatory disorders and includes patients with rheumatoid arthritis, osteomyelitis, ankylosing spondylitis, inflammatory bowl disease, tuberculosis, leprosy, Hodgkin's disease, renal cell carcinoma, and Familial Mediterranean Fever. The consequences of fibrillar AA amyloid deposition in systemic organs are usually fatal to patients, with most patients dying within 3-7 years from disease onset due to kidney or heart failure. Currently there is no effective cure treatment for AA amyloidosis and a new therapeutic is desperately needed for the ~100,000 cases currently in the USA. In our completed Phase I SBIR studies we designed, synthesized and tested our own unique library of small molecule compounds (representing new chemical entities) for inhibition of AA amyloidosis both in vitro and in vivo. Using a variety of in vitro screening methods to identify specific potent inhibitors of AA amyloidosis, we discovered that a number of our small molecule compounds markedly disrupted/inhibited SAA/AA amyloid fibrils in vitro. Using a relevant animal mouse model of experimental AA amyloidosis we now have identified 2 lead compounds (i.e. PTI-19 and 51) that remarkably inhibit AA amyloid deposition in tissues (i.e. spleen, liver and kidney) by >50-60% following oral administration. PTI-19 and 51 represent new chemical entities and our established synthetic routes for the repeated production of each of these compounds demonstrate a pure product (>98% purity) that consists of only 1 compound and 1 stereoisomer [(as determined by detailed analysis including HPLC/mass spec, 1H-NMR, 13C-NMR, DEPT, and x-ray crystallography (for PTI-19)]. These studies suggest that these small molecule lead compounds show great promise for the development of new effective treatments for systemic AA amyloidosis and warrant further investigation as described in this Phase II SBIR project. In proposed Phase II studies we will work with two world class organic chemists and optimize, test and further develop these small molecule compounds (including our 2 lead compounds) that we anticipate will inhibit/retard and cause a clearance of aggregated/fibrillar AA amyloid deposits in humans. In vitro testing against human AA amyloid fibrils will include newly designed analogs optimized for oral bioavailability and enhanced PK characteristics, while maintaining non-toxicity and potent efficacy. Confirmation of each final product synthesized and the possible existence of stereoisomers will be determined using 1H-NMR, 13C-NMR and DEPT. X-ray crystallography will also be used for promising lead compounds in which absolute determination of stereochemistry cannot be fully verified by NMR. Oral administration and time-dependent efficacy for prevention, reduction and clearance of AA amyloid deposits in systemic organs will be assessed using two experimental AA amyloid mouse models. PK and toxicity studies will help us optimize a novel small molecule compound (and its back-up) that will be developed for human clinical trials and commercialization, and that has promise to serve as a new treatment for systemic AA amyloidosis and related diseases. PUBLIC HEALTH RELEVANCE: Systemic AA Amyloidosis is usually a fatal disease characterized by fibrillar amyloid deposition throughout the body that leads to organ dysfunction and eventually death in 3-7 years (due to kidney and/or heart failure). We have designed and discovered new small molecule compounds that effectively reduce/inhibit amyloid deposition in organs in a relevant animal model that mimics the human disease. In this project we intend to develop a new drug (and back-up) for effective treatment of ~100,000 cases of systemic amyloidosis in the USA, for which today there is no real treatment whatsoever.