Preclinical optimization of a gene therapy for erythromelalgia and chronic pain

摘要 慢性疼痛是指持续超过正常愈合时间的疼痛。15亿人 全世界患有慢性疼痛，随着老年人口的增加，这一数字还在继续增加 糖尿病患病率上升，癌症存活率提高。慢性疼痛不仅 严重影响了许多患者的日常生活质量，也给社会经济造成了沉重的负担 给社会带来负担。由于可用有效治疗选择的数量有限，慢性 疼痛通常用阿片类药物治疗，尽管有成瘾和副作用的风险。不幸的是， 开阿片类药物治疗慢性疼痛在很大程度上助长了目前的阿片类药物流行。 因此，对非成瘾性替代镇痛剂的需求迫切且明显未得到满足。 慢性疼痛的治疗。推动开发特定的、不会上瘾的替代品 止痛药引起了人们对一种特殊的钠通道Nav1.7的兴趣，它被证明对 疼痛感应。Nav1.7中的功能获得突变与一种特征性疾病相关 四肢剧烈灼痛：原发性红斑性肢痛症。反之，功能丧失 Nav1.7的结果是无法感觉到疼痛。因此，抑制Nav1.7可能是一种有效的 减轻疼痛和治疗红斑性肢痛症的方法。为了实现这一点，我们设计了 表观遗传调节子抑制Nav1.7的表达。而不是永久编辑 这些表观遗传调节子将暂时抑制Nav1.7的表达。通过锁定目标 Nav1.7在DNA层面上，我们可以实现对Nav1.7的特定和持久的调制，通过 比RNA和蛋白质靶向方法有更好的药代动力学前景。在这项研究中，我们 建议优化这些表观遗传调节子以及它们的传递，以实现高 特异性和有效性。此外，我们还将对我们优化的调制器进行小规模的评估 在大型动物模型中进行制造研究和毒理学研究。其结果是 研究将是一种优化的基因疗法，不仅不会使人上瘾，而且对治疗有效 不仅是慢性疼痛，而且是高度特异和持久的。

ABSTRACT Chronic pain is pain that persists past the normal time of healing. 1.5 billion people worldwide suffer from chronic pain and this number continues to increase as the elderly population grows, the prevalence of diabetes rises, and cancer survival rates improve. Chronic pain not only severely impacts daily quality of life for many patients, it also places a heavy socioeconomic burden on society. Due to the limited number of efficacious treatment options available, chronic pain is often treated with opioids despite the risk of addiction and side effects. Unfortunately, the prescribing of opioids to treat chronic pain has largely fueled the current opioid epidemic. Therefore, there is an urgent and clear unmet need for non-addictive alternative analgesics for the treatment of chronic pain. The push to develop specific and non-addictive alternative painkillers has brought interest to a particular sodium channel, NaV1.7, shown to be important for pain sensing. Gain-of-function mutations in NaV1.7 are associated with a disorder characterized by intense burning pain in the extremities: primary erythromelalgia. Conversely, loss-of function of NaV1.7 results in the inability to feel pain. Therefore, inhibiting NaV1.7 can be an effective method of reducing pain and treat erythromelalgia patients. To accomplish this, we designed epigenetic modulators to repress expression of NaV1.7. Rather than making permanent edits to the genome, these epigenetic modulators will transiently inhibit expression of NaV1.7. By targeting NaV1.7 at the DNA-level, we can achieve specific and long-lasting modulation of NaV1.7, with better pharmacokinetics prospects than RNA- and protein-targeting approaches. In this study, we propose to optimize these epigenetic modulators as well as their delivery in order to achieve high specificity and efficacy. In addition, we will evaluate our optimized modulators in small-scale manufacturing studies as well as toxicological studies in a large animal model. The result of this study will be an optimized gene therapy that is not only non-addictive and efficacious for treatment of chronic pain but also highly specific and long-lasting.