Antisense oligonucleotide treatment for myotonic dystrophy

描述（由申请人提供）：强直性肌营养不良1型（DM 1）是一种相对常见的肌营养不良。遗传基础是DMPK 3'非翻译区CTG重复序列的扩增，DMPK是编码在骨骼肌、心肌和平滑肌以及神经元中表达的蛋白激酶的基因。这种不寻常的突变引起RNA优势，其中含有扩增的CUG（CUG“”）重复序列的RNA的表达导致细胞功能障碍。突变体RNA在核灶中积累，并启动复杂的下游事件级联，例如RNA剪接调控缺陷。因此，一种有吸引力的治疗方法是通过加速有毒RNA的清除来从根本上解决问题。为此，我们提出开发靶向突变型人DMPK（mut-hDMPK）mRNA的RNA酶H活性反义寡核苷酸（ASO）。以往的研究表明ASO在骨骼肌和骨骼肌中的生物分布和活性较低。相比之下，我们已经发现，当靶向保留在细胞核中的转录物时，全身递送的ASO在野生型小鼠的肌肉中具有高度活性-大概是因为这是RNA酶H具有活性的隔室。因此，我们假设CUG扩增的转录物也可能在肌肉中显示有效的敲除，因为它们也保留在细胞核中。与这一观点一致，在转基因小鼠中，皮下给予阿索4周引起肌肉中CUG（R）“转录物的高效敲低、RNA剪接紊乱的逆转和肌强直的挽救。我们现在寻求开发靶向mut- hDMPK转录物用于在骨骼肌和心肌中裂解的最佳有效的、系统活性的ASO。开发计划要求鉴定在细胞中具有高度活性的ASO，选择在转基因小鼠中显示最佳mut-hDMPK敲低的ASO，消除在啮齿动物和猴中显示不可接受的毒性的ASO，然后使用GMP制造的药物进行IND使能毒理学/药理学研究。为了实现这些目标，我们已经形成了一个学术-商业合作，包括所有的科学，临床，监管和制造专业知识，这是需要把药物治疗DM 1的临床。

DESCRIPTION (provided by applicant): Myotonic dystrophy type 1 (DM1) is a relatively common form of muscular dystrophy. The genetic basis is an expansion of CTG repeats in the 3' untranslated region of DMPK, a gene encoding a protein kinase expressed in skeletal, cardiac, and smooth muscle, and in neurons. This unusual mutation gives rise to RNA dominance, in which expression of RNA containing an expanded CUG (CUG^"'') repeat leads cell dysfunction. The mutant RNA accumulates in nuclear foci and initiates a complex cascade of downstream events, such as, defects in the regulation of RNA splicing. An attractive therapeutic approach, therefore, is to attack the problem at its root cause, by accelerating the clearance of the toxic RNA. To this end, we are proposing to develop RNase H-active antisense oligonucleotides (ASOs) targeting the mutant human DMPK {mut-hDMPK) mRNA. Previous studies have indicated that biodistribution and activity of ASOs in skeletal and candiac muscle is low. In contrast, we have found that systemically-delivered ASOs are highly active in muscle of wild-type mice, when targeted against a transcript that is retained in the nucleus - presumably because this is the compartment in which RNase H is active. We therefore postulated that CUG-expanded transcripts may also show efficient knockdown in muscle, because they also are retained in the nucleus. Consistent with this idea, subcutaneous administration of ASO for four weeks caused highly effective knockdown of CUG(R)"'' transcripts in muscle, reversal of RNA splicing derangements, and rescue of myotonia in transgenic mice. We seek now to develop optimally-effective, systemically-active ASOs that target mut- hDMPK transcripts for cleavage in skeletal and cardiac muscle. Development plans call for identification of ASOs that are highly active in cells, selection of ASOs that show optimal mut-hDMPK knockdown in transgenic mice, elimination of ASOs that show unacceptable toxicity in rodents and monkeys, and then IND- enabling toxicology/pharmacology studies using GMP-manufactured drug. To accomplish these goals we have formed an academic-commercial collaboration that includes all of the scientific, clinical, regulatory, and manufacturing expertise that is needed to bring a drug treatment for DM1 to the clinic.