Systemic AA Amyloidosis Inhibitors

描述（由申请人提供）：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器官，包括心、肾、肝、脾、肺、皮肤和胃肠道，这种淀粉样纤维积聚导致明显的器官功能障碍。系统性AA淀粉样变主要与慢性炎症性疾病相关，包括类风湿关节炎、骨髓炎、强直性脊柱炎、炎症性碗病、结核病、麻风病、霍奇金病、肾细胞癌和家族性地中海热。纤维状AA淀粉样蛋白沉积在全身器官中的后果通常对患者是致命的，大多数患者在发病后3-7年内因肾脏或心力衰竭而死亡。目前还没有有效的治疗AA淀粉样变性的方法，目前在美国的约10万例患者迫切需要一种新的治疗方法。在我们完成的I期SBIR研究中，我们设计、合成并测试了我们自己独特的小分子化合物库（代表新的化学实体），用于体外和体内抑制AA淀粉样变性。使用多种体外筛选方法来鉴定AA淀粉样变性的特异性有效抑制剂，我们发现许多我们的小分子化合物在体外显着破坏/抑制SAA/AA淀粉样原纤维。通过相关的实验性AA淀粉样变性动物小鼠模型，我们现在已经鉴定出两种先导化合物（即PTI-19和51）在口服后显著抑制组织（即脾、肝和肾）中的AA淀粉样蛋白沉积，其抑制率为bbb50 -60%。PTI-19和51代表了新的化学实体，我们建立的重复生产这些化合物的合成路线证明了一种纯产品（纯度约为98%），仅由1种化合物和1种立体异构体组成[(通过详细分析确定，包括HPLC/质谱，1H-NMR, 13C-NMR， DEPT和x射线晶体学（用于PTI-19）]。这些研究表明，这些小分子先导化合物为开发新的系统性AA淀粉样变性有效治疗方法提供了巨大的希望，值得在SBIR二期项目中进一步研究。在拟议的II期研究中，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（包括我们的两种先导化合物），我们预计这些化合物将抑制/延缓并导致人类聚集/纤维状AA淀粉样蛋白沉积的清除。体外抗人AA淀粉样原纤维的试验将包括新设计的优化口服生物利用度和增强PK特性的类似物，同时保持无毒和有效。每个合成的最终产物和可能存在的立体异构体的确认将使用1H-NMR， 13C-NMR和DEPT来确定。x射线晶体学也将用于有前途的先导化合物，其中立体化学的绝对测定不能完全通过NMR来验证。采用两种实验性AA淀粉样蛋白小鼠模型，评估口服给药和时间依赖性的AA淀粉样蛋白沉积在全身器官中的预防、减少和清除效果。PK和毒性研究将帮助我们优化一种新的小分子化合物（及其备份），该化合物将用于人体临床试验和商业化，并有望作为系统性AA淀粉样变性和相关疾病的新治疗方法。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，其特征是纤维样淀粉样蛋白遍布全身，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）。我们已经设计并发现了新的小分子化合物，可以在模拟人类疾病的相关动物模型中有效地减少/抑制器官中的淀粉样蛋白沉积。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10万例系统性淀粉样变性，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.