Identification and Characterization of Modified Antisense Oligonucleotides Targeting DMPK in Mice and Nonhuman Primates for the Treatment of Myotonic Dystrophy Type 1
Identification and Characterization of Modified Antisense Oligonucleotides Targeting DMPK in Mice and Nonhuman Primates for the Treatment of Myotonic Dystrophy Type 1
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DOI：
10.1124/jpet.115.226969
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发表时间：
2015-11-01
影响因子：
3.5
通讯作者：
MacLeod, A. Robert
中科院分区：
文献类型：
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作者：
Pandey, Sanjay K.;Wheeler, Thurman M.;MacLeod, A. Robert
强直性肌营养不良1型（DM 1）是成人中最常见的肌营养不良形式。DM 1是由DMPK（编码肌营养不良蛋白激酶（DMPK）的基因）3 '非翻译区的CTG重复序列扩增引起的。相对于用其他2 '-化学修饰的那些，含有2'，4 '-限制性乙基修饰（cEt）残基的反义寡核苷酸（ASO）表现出显著增加的RNA结合亲和力和体内效力，我们推测这可以转化为在肝外组织（例如肌肉）中增强的活性。在这里，我们描述了cEt缺口聚物DMPK阿索（ISIS 486178）的设计和表征，其在体外和体内对小鼠、猴和人DMPK具有有效活性。向野生型小鼠全身递送未配制的ISIS 486718使肝脏和骨骼肌中的DMPK mRNA水平降低高达90%。类似地，用ISIS 486178处理人DMPK转基因小鼠或食蟹猴导致两个物种中多个骨骼肌中DMPK抑制高达70%，心肌中DMPK抑制类似于50%。重要的是，DMPK的抑制耐受性良好，并且与任何骨骼肌或心脏毒性无关。同样有趣的是，在小鼠和猴中，肌肉中DMPK mRNA水平的抑制分别维持长达16周和13周的治疗后。这些结果表明，cET修饰的ASO在骨骼肌中显示出有效的活性，并且这种有吸引力的治疗方法保证了进一步的临床研究以抑制DM 1发病机制的功能获得性毒性RNA。
Myotonic dystrophy type 1 (DM1) is the most common form of muscular dystrophy in adults. DM1 is caused by an expanded CTG repeat in the 3'-untranslated region of DMPK, the gene encoding dystrophiamyotonica protein kinase (DMPK). Antisense oligonucleotides (ASOs) containing 2',4'-constrained ethylmodified (cEt) residues exhibit a significantly increased RNA binding affinity and in vivo potency relative to those modified with other 2'-chemistries, which we speculated could translate to enhanced activity in extrahepatic tissues, such as muscle. Here, we describe the design and characterization of a cEt gapmer DMPK ASO (ISIS 486178), with potent activity in vitro and in vivo against mouse, monkey, and human DMPK. Systemic delivery of unformulated ISIS 486718 to wild-type mice decreased DMPK mRNA levels by up to 90% in liver and skeletal muscle. Similarly, treatment of either human DMPK transgenic mice or cynomolgus monkeys with ISIS 486178 led to up to 70% inhibition of DMPK in multiple skeletal muscles and similar to 50% in cardiac muscle in both species. Importantly, inhibition of DMPK was well tolerated and was not associated with any skeletal muscle or cardiac toxicity. Also interesting was the demonstration that the inhibition of DMPK mRNA levels in muscle was maintained for up to 16 and 13 weeks post-treatment in mice and monkeys, respectively. These results demonstrate that cEt-modified ASOs show potent activity in skeletal muscle, and that this attractive therapeutic approach warrants further clinical investigation to inhibit the gain-of-function toxic RNA underlying the pathogenesis of DM1.