Discovery and optimization of novel mutant-selective allosteric inhibitors of EGFR T790M

摘要： 表皮生长因子受体(EGFR)酪氨酸激酶域的体细胞突变是一种 肺腺癌的常见病因。尽管EGFR突变肺的靶向治疗取得了显著进展 癌症，治疗获得性耐药性仍然是一个主要问题。 了解和克服对EGFR酪氨酸激酶抑制剂(TKIs)的获得性耐药性 其他靶向治疗是癌症医学的一个中心问题。我们的长期目标是开发更有效的产品 以及对EGFR突变肺癌更好的耐受性治疗，产生持久的反应。我们认为 同时使用多个靶向突变EGFR的药物可防止耐药性的出现 突变，导致更持久的反应。然而，具有替代机制的合适的化合物 之前还没有可用的操作。像绝大多数的TKI一样，目前所有的EGFR TKI都以ATP为目标- 激活酶的位置。我们的多学科研究团队在EGFR突变肺癌方面拥有深厚的专业知识 成功发现抑制剂的记录。在最初的资助期间，我们开发了高效的变构抑制剂。 基于苯甘氨酸支架，该支架作为单剂有效地对抗L858R/T790M和 L858R/T790M/C797S EGFR变异体的体外和小鼠非小细胞肺癌模型。这个 这些变构抑制剂不同的作用机制和结合部位，以及它们对 WT、EGFR和其他蛋白激酶，使它们作为联合治疗的候选药物特别有吸引力。 在这次更新中，我们将发现以ATP和变构为靶点的化合物是否真的可以 协同作用，提供前所未有的疗效、耐受性和持久性的回应。我们通过以下途径实现这一目标 具体目标如下：目标1，我们将开发第二个高效、突变选择性强的化学系列 基于苯二氮卓酮支架的变构EGFR抑制剂。目标2，我们将设计和优化 同时与突变的EGFR的相邻ATP和变构位点结合的互补的抑制剂对 具有高度的积极合作精神。据我们所知，高度合作、多部位抑制并没有 以前在治疗开发的背景下进行了探索。目标3，我们将执行临床前验证 变构EGFR抑制剂和互补的ATP位点/变构对，包括测试它们的体内疗效 在EGFR突变肺癌的异种移植模型中，并评估在此背景下产生耐药性的可能性 双重目标。这些目标的成功实现将为新的治疗方法提供概念证明 在EGFR突变的肺癌中。

Abstract: Somatic mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) are a common cause of lung adenocarcinoma. Despite marked advances in targeted therapies for EGFR-mutant lung cancer, treatment-acquired resistance remains a major problem. Understanding and overcoming acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) and to other targeted therapies is a central problem in cancer medicine. Our long term goal is to develop more effective and better tolerated therapies for EGFR mutant lung cancer that yield durable responses. We reason that simultaneous treatment with multiple agents targeting mutant EGFR may prevent emergence of resistance mutations, leading to more durable responses. However, suitable compounds with alternative mechanisms of action have not previously been available. Like the vast majority of TKIs, all current EGFR TKIs target the ATP- site of the kinase. Our multidisciplinary research team has deep expertise in EGFR-mutant lung cancer and a record of successful inhibitor discovery. In the initial grant period, we developed highly potent allosteric inhibitors based on a phenylglycine scaffold that are effective as single agents against L858R/T790M and L858R/T790M/C797S EGFR variants in vitro and in mouse models of human non-small cell lung cancer. The distinct mechanism of action and binding site of these allosteric inhibitors, together with their lack of potency on WT EGFR and other protein kinases, makes them especially attractive as candidates for combination therapy. In this renewal, we will discover whether compounds that target the ATP and allosteric sites can indeed synergize to deliver unprecedented efficacy, tolerability and durability of responses. We pursue this goal through the following specific aims: Aim 1, We will develop a second chemical series of highly potent, mutant-selective allosteric EGFR inhibitors based on a benzodiazepinone scaffold. Aim 2, We will design and optimize complementary pairs of inhibitors that simultaneously bind the adjacent ATP and allosteric sites of mutant EGFR with a high degree of positive cooperativity. To our knowledge, highly cooperative, multi-site inhibition has not been previously explored in the context of therapeutic development. Aim 3, We will perform pre-clinical validation of allosteric EGFR inhibitors and complementary ATP-site/allosteric pairs, including testing their in vivo efficacy in xenograft models of EGFR mutant lung cancer and assessing the potential for resistance to arise in the context of dual targeting. Successful execution of these aims will provide proof of concept for a new therapeutic approach in EGFR mutant lung cancer.