Evaluating the Blood-Brain Barrier Bioavailability and in vivo Efficacy Potential of a Novel TAK1 Inhibitor Targeting Chronic Pain

项目概要/摘要 慢性疼痛是一个普遍的健康问题，影响多达1亿人，并带来经济负担 仅在美国每年就高达5600亿美元，但治疗选择仍然有限。非处方非甾体 抗炎药（NSAID）是短效的，不能缓解严重的慢性疼痛， 常规药物在胃肠道事件方面存在严重的安全性问题。此外，较新的和 选择性更强的考克斯-2抑制剂如西乐葆®/塞来昔布和万络®带有FDA黑框警告， 心脏病发作和中风的严重风险。类似地，长效中枢靶向疗法如阿片类药物也 疗效差，并产生严重的副作用，如精神状态改变、成瘾和呼吸系统疾病。 萧条因此，对于患有癌症的患者，存在对当前治疗选择的替代方案的严重未满足的需求。 慢性疼痛。慢性疼痛的主要驱动因素之一是组织损伤或神经损伤后的炎症 肿瘤坏死因子α（TNF）等细胞因子水平升高所致，且存在正相关性 肿瘤坏死因子水平和疼痛强度之间的关系。TNF可以与位于原代细胞末端的TNFR 1受体结合， 传入伤害感受器直接增加其活性，并且还可以刺激促炎细胞因子 生产和免疫细胞激活。我们的临床前工作已经确定了TGFβ激活激酶1（TAK 1）， 介导的TNF促存活/炎症反应途径中的关键信号传导元件。TAK 1扮演着关键的角色， 在促进蛋白激酶介导的信号通路的激活中的作用， 慢性疼痛过程，因此已经成为调节慢性疼痛的新靶点， 炎症与增强的TNF信号传导有关。我们最近发现的takinib支架已经确定了一种 高选择性、强效（IC 50 ~ 2.5 nM）、口服生物可利用的TAK 1小分子抑制剂（takinib类似物 HS-276）。临床前研究表明，使用母体takinib抑制TAK 1可产生9倍的 TNF水平的降低以及参与促炎性细胞因子的其他细胞因子和趋化因子水平的降低， 应答此外，TAK 1抑制与母体takinib预防机械和热疼痛，疼痛相关 抑郁行为和炎性疼痛模型中的水肿。此外，在此研究中， 模型降低了促炎细胞因子和趋化因子蛋白表达。为了成功地实现 takinib类似物HS-276的概念验证，该项目包括三个具体目标：目标1 -评价 HS-276在血脑屏障（BBB）生物利用度方面的药代动力学。目标2 -确定 HS-276在阿托伐他汀诱导的关节炎小鼠模型中确立的（治疗）镇痛潜力 通过机械和热疼痛以及炎性细胞因子的减少来证明炎性疼痛。 目的3 -确定HS-276在链脲佐菌素诱导的小鼠模型中的治疗镇痛潜力。 糖尿病神经病变实现上述具体目标将为我们提供必要的数据， 寻求II期NIH SBIR申请，以资助IND使能安全性研究，并进行I期临床试验。

Project Summary / Abstract Chronic pain is a prevalent health concern, affecting up to 100 million people and carrying an economic burden up to $560 billion annually in the US alone, yet treatment options remain limited. Over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) are short-acting and fail to alleviate severe chronic pain, and these conventional drugs carry serious safety concerns regarding gastrointestinal events. In addition, the newer and more selective COX-2 inhibitors such as Celebrex®/celecoxib and Vioxx® carry FDA boxed warnings concerning serious risks of heart attack and stroke. Similarly, longer-acting centrally-targeted therapies such as opioids also have poor efficacy and produce serious side-effects regarding altered mental state, addiction, and respiratory depression. Thus, there is a serious unmet need for alternatives to current treatment options for patients suffering with chronic pain. One of the main drivers of chronic pain is inflammation following tissue injury or nerve injury caused by increased levels of cytokines such as tumor necrosis factor α (TNF), and a positive correlation exists between TNF levels and pain intensity. TNF can bind to its TNFR1 receptor located on the terminals of primary afferent nociceptors to directly increase their activity, and can also stimulate pro-inflammatory cytokine production and immune cell activation. Our preclinical work has identified TGFβ-activated kinase 1 (TAK1), a key signaling element in the mediated TNF pro-survival/inflammatory response pathway. TAK1 plays a crucial role in facilitating activation of protein kinase-mediated signaling pathways implicated in the pathogenesis of chronic pain processes, and as a result has emerged as a novel target for regulating chronic pain and inflammation linked to enhanced TNF signaling. Our recent discovery of the takinib scaffold has identified a highly selective, potent (IC50 ~2.5nM), and orally bioavailable small molecule inhibitor of TAK1 (takinib analog HS-276). Preclinical studies have demonstrated that TAK1 inhibition with parent takinib produces a 9-fold reduction in TNF levels alongside reduced levels of other cytokines and chemokines involved in pro-inflammatory responses. Also, TAK1 inhibition with parent takinib prevented mechanical and thermal heat pain, pain-related depressive behavior, and edema in a model of inflammatory pain. Furthermore, parent takinib treatment in this model reduced pro-inflammatory cytokine and chemokine protein expression. In order to successfully attain proof-of-concept for takinib analog HS-276, this project includes three Specific Aims: Aim 1 – Evaluate the pharmacokinetics of HS-276 regarding blood-brain barrier (BBB) bioavailability. Aim 2 – Determine the established (therapeutic) analgesic potential of HS-276 in a monosodium urate-induced arthritis mouse model of inflammatory pain evidenced by reduction in mechanical and thermal pain, as well as inflammatory cytokines. Aim 3 – Determine the therapeutic analgesic potential of HS-276 in a streptozotocin-induced mouse model of diabetic neuropathy. Achieving the Specific Aims above will provide will provide the necessary data for us to pursue a Phase II NIH SBIR application to fund IND-enabling safety studies en route to a Phase I clinical trial.