Oxidation-resistant Anti-protease Therapy

抽象的。LEXEO Therapeutics，LLC是一家早期生物技术公司，专注于使用基因 治疗技术，以保护脆弱的器官免受氧化应激。LEX 01是LEXEO的第一款产品， 第一次在类，下一代基因疗法治疗α 1-抗胰蛋白酶（AAT）缺乏症，一个常染色体 与低血清AAT水平相关的隐性遗传性疾病。AAT（SERPINA 1），一种52 kDa丝氨酸 由肝脏产生的抗蛋白酶，保护肺部免受炎症释放的蛋白水解酶的影响。 细胞在AAT缺乏症中，肺容易被炎症释放的蛋白水解酶破坏， 炎症细胞降解肺，导致肺气肿。目前，AAT缺乏症的治疗方法是 每周输注从合并的人血浆中纯化的AAT。AAT缺乏症的基因治疗 承诺单次给药将产生足够量的AAT，以保护持续性肺损伤， 帐篷的基础上，避免每周AAT蛋白治疗。第一代基因治疗策略正在开发中， 使用腺相关病毒（AAV）基因转移载体来递送AAT缺陷的方法 人AAT编码序列。这些战略的致命弱点是感觉- AAT分子对氧化剂的活性。人AAT的活性位点包括Met 358，具有2°贡献。 我的Met 351当被氧化时（例如，香烟烟雾，炎症细胞产物，环境污染）， AAT是无效的，不能抑制中性粒细胞弹性蛋白酶，其主要目标。LEX 01，设计为 编码弹性蛋白酶抑制性、抗氧化性人AAT的AAV载体解决了这个问题， 在Met 358和/或Met 351处被瓦尔或Leu取代以使AAT分子氧化还原， 但仍保持其作为抗弹性蛋白酶的功能。这是一个快速通道应用程序的目标是- 在3年内完成临床试验。成功完成这些目标将使LEEO对 生物技术、制药和/或风险投资。第一阶段，目标1。使用正常的M1（A213）AAT编码 序列作为碱基，评估位置351和358处的Met、Leu和瓦尔的组合，以确定对应的氨基酸序列。 AAT的最佳中性粒细胞弹性蛋白酶抑制、抗氧化形式用于LEX 01。第一阶段目标2。 确定实验动物胸膜内给予LEX 01导致持续的高水平 血清和肺上皮衬里液中抗氧化人AAT的测定。第一阶段，目标3。有一个预- IND与FDA就LEX 01开发计划举行会议。第二阶段，目标1。生产和验证 GMP临床级LEX 01，并在实验动物中证明其可安全用于人体试验。 第二阶段，目标2。开发并验证临床研究中使用的检测试剂盒。向FDA提交 IND允许启动针对AAT缺乏症的LEX 01 I期临床研究。

Abstract. LEXEO Therapeutics, LLC, is an early stage biotechnology company focused on using gene therapy technologies to protect vulnerable organs from oxidant stress. LEX01, the 1st LEXEO product, is a 1st in class, next generation gene therapy treatment for alpha 1-antitrypsin (AAT) deficiency, an autosomal recessive hereditary disorder associated with low serum levels of AAT. AAT (SERPINA1), a 52 kDa serine antiprotease produced by the liver, protects the lung from proteolytic enzymes released by inflammatory cells. In AAT deficiency, the lung is vulnerable to destruction by proteolytic enzymes released by inflam- matory cells that degrade the lung, resulting in emphysema. AAT deficiency is currently treated with weekly infusions of AAT purified from pooled human plasma. Gene therapy for AAT deficiency holds the promise that a single administration will generate sufficient amounts of AAT to protect the lung on a persis- tent basis, obviating weekly AAT protein therapy. First generation gene therapy strategies are under de- velopment to treat AAT deficiency using adenoassociated virus (AAV) gene transfer vectors to deliver the human AAT coding sequence in vivo by various routes. The Achilles heel of these strategies is the sensi- tivity of the AAT molecule to oxidants. The active site of human AAT includes Met358, with a 2° contribu- tion by Met351. When oxidized (e.g., by cigarette smoke, inflammatory cell products, ambient pollution), AAT is rendered ineffective and cannot inhibit neutrophil elastase, its primary target. LEX01, designed as an AAV vector coding for an elastase-inhibiting, oxidation-resistant human AAT, solves this prob- lem with substitution at Met358 and/or Met351 with Val or Leu to render the AAT molecule oxidation re- sistant, yet maintaining its function as an anti-elastase. This is a Fast Track application with the goal of be- ing clinical trial-ready within 3 yr. Successful completion of these aims will make LEXEO attractive for biotech, pharma and/or venture investment. Phase I, Aim 1. Using the normal M1(A213) AAT coding sequence as a base, assess combinations of Met, Leu and Val at positions 351 and 358 to determine the optimal neutrophil elastase inhibiting, oxidation resistant form of AAT to use in LEX01. Phase I, Aim 2. Determine that intrapleural administration of LEX01 to experimental animals results in persistent, high lev- els of oxidation-resistant human AAT in serum and lung epithelial lining fluid. Phase I, Aim 3. Have a pre- IND meeting with the FDA regarding the LEX01 development plan. Phase II, Aim 1. Produce and validate GMP clinical grade LEX01 and demonstrate in experimental animals it is safe to use in a human trial. Phase II, Aim 2. Develop and validate the assays to be used in the clinical study. Submit to the FDA an IND permitting initiation of a phase I clinical study of LEX01 for AAT deficiency.