Phase IIA Trial of Dichloroacetate for Glioblastoma Multiforme, IND137007, 09172019

摘要： 多形性胶质母细胞瘤（GBM），一种IV级胶质瘤，是恶性胶质瘤的最恶性形式。 星形细胞瘤是成人最常见的恶性脑肿瘤。这次初选的原因 和高度侵袭性的癌症尚不清楚。目前对胶质母细胞瘤的治疗仅限于 最安全的手术切除，然后化疗和放疗。不幸的是， 几乎所有的病人都会有肿瘤复发并死于这种疾病。虽然生存没有 治疗大约3个月，治疗后的生存期只有12至15个月。 只有不到5%的人能活五年以上。 肿瘤发生的一个主要代谢特征是糖酵解， 即使在存在足够的组织氧的情况下， 磷酸化（OXPHOS），一种被称为瓦尔堡效应的现象。这种糖酵解转变 发生在GBM中，并且在机制上与以下蛋白的翻译后抑制相关： 线粒体丙酮酸脱氢酶复合物（PDC），通常催化限速 葡萄糖衍生的丙酮酸盐和乳酸盐的有氧氧化步骤。PDC抑制是由于 四种丙酮酸脱氢酶激酶同工型（PDK）中的一种或多种的转录上调 1-4)其通过可逆磷酸化抑制PDC。二氯乙酸盐（DCA），原型PDK 抑制剂，很容易穿过血脑屏障，代表了一个全新的小类 分子代谢调节剂，在线粒体中发挥作用，以重置各种细胞内稳态， 先天性和获得性代谢紊乱。事实上，癌症中PDK的药理学抑制 DCA可恢复PDC活性，逆转瓦尔堡效应，并诱导caspase介导的细胞凋亡。 肿瘤的选择性凋亡。广泛的临床前研究和早期患者临床试验 复发性GBM和其他脑肿瘤的患者表明，DCA可能是一种安全且独特有效的 GBM的代谢治疗 DCA抑制自身代谢，其唯一的临床限制性毒性是可逆的外周毒性 神经病变为了减轻这种不利影响，我们开发并验证了基因分型方法 对于基于遗传学的DCA给药，将受试者分为快速和慢速药物 代谢者，导致安全，个性化的DCA给药。

Abstract: Glioblastoma multiforme (GBM), a grade IV glioma, is the most malignant form of an astrocytoma and is the most common malignant brain tumor in adults. The cause of this primary and highly aggressive cancer is unclear. The current treatment for glioblastoma is limited to maximal safe surgical resection, followed by chemotherapy and radiation therapy. Unfortunately, virtually all patients will have tumor recurrence and die of this disease. While survival without treatment is approximately three months, survival following treatment is only 12 to 15 months. Less than 5% of people survive longer than five years. A cardinal metabolic characteristic of tumorigenesis is a metabolic shift in which glycolysis, even in the presence of adequate tissue oxygen, increases disproportionately relative to oxidative phosphorylation (OXPHOS), a phenomenon known as the Warburg effect. This glycolytic shift occurs in GBM and is mechanistically associated with post-translational inhibition of the mitochondrial pyruvate dehydrogenase complex (PDC), which normally catalyzes the rate-limiting step in the aerobic oxidation of glucose-derived pyruvate and lactate. PDC inhibition is due to transcriptional upregulation of one or more of four pyruvate dehydrogenase kinase isoforms (PDK 1-4) that inhibit PDC by reversible phosphorylation. Dichloroacetate (DCA), the prototypic PDK inhibitor, readily crosses the blood-brain barrier and represents an entirely new class of small molecule metabolic modulators that act in mitochondria to reset cellular homeostasis in various congenital and acquired metabolic disorders. Indeed, pharmacological inhibition of PDK in cancer cells by DCA restores PDC activity, reverses the Warburg effect and induces a caspase-mediated selective apoptosis of tumors. Extensive pre-clinical research and early clinical trials in patients with recurrent GBM and other brain tumors indicate that DCA may be a safe and uniquely effective metabolic therapy for GBM. DCA inhibits its own metabolism and its only clinically limiting toxicity is reversible peripheral neuropathy. To mitigate this adverse effect, we developed and validated a genotyping method for genetics-based dosing of DCA that dichotomizes subjects into fast and slow drug metabolizers, leading to safe, personalized DCA dosing.