Development of a PIKFYVE antisense oligonucleotide treatment for FTD

PIKFYVE抑制反义寡核苷酸治疗FTD的研究进展 项目摘要 额颞叶痴呆(FTD)是一种复杂的疾病，由许多不同的遗传病因引起。那里 没有任何药物可以延缓FTD的进展。尽管针对特定原因的治疗策略 突变(例如C9ORF72 ASO)可能被证明对个别形式的FTD有效，但这些方法不能 解决绝大多数遗传病因不明的病例。此外，考虑到大量的 可能导致FTD的不同基因，以及每种遗传形式相对罕见的事实，这一策略 可能很难在所有情况下实施。因此，迫切需要新的治疗策略，以 挽救多种形式的FTD，特别是那些遗传原因不明的FTD。 45%的FTD患者皮质神经元中有TDP-43的胞浆聚集物，另有45%的患者有TDP-43的胞浆聚集体 牛磺酸聚合体。研究表明，这些神经元TDP-43和tau聚合体推动神经退行性变。因此， 为了确定FTD的新治疗靶点，我们使用细胞重新编程来产生诱导的皮质 显示TDP-43聚集体的C9ORF72 FTD患者和MAPT FTD患者的神经元(INS)， 他们藏匿着陶器聚合体。然后，我们进行了化学筛选，以确定拯救退化的靶点 C9ORF72和MAPT FTD INS。PIKfyve激酶的抑制剂是最有效的化合物之一 在C9ORF72和MAPT FTD INS上。反义寡核苷酸(ASO)介导的PIKfyve抑制作用 证实阻止PIKfyve活动可以挽救FTD的生存。 与小分子相比，反义寡核苷酸(ASO)提供了一种简便的靶向靶向 中枢神经系统，因为它们可以直接注射到脊髓，在整个过程中实现持续的靶向接触 中枢神经系统，不太可能引起外周毒性。因此，我们正在寻求ASO中介的抑制 PIKfyve作为一种治疗各种形式的ALS的方法。我们已经筛选了数百名人类 PIKfyve ASO，并在体外鉴定了10个具有有效PIKfyve击倒作用的铅ASO。我们有 测试了数百个人类PIKfyve ASO，并确定了三个有希望的开发线索。这个 这一直接到第二阶段提案的目标是进一步表征PIKfyve的疗效 抑制，以及铅ASO的安全性，以选择真正的开发候选者 GLP毒性研究进展。我们发现分泌性自噬是一种治疗方法 神经变性对该领域的影响很大，因为激活了蛋白酶体和自噬 在神经退行性变模型中的结果好坏参半。

Development of a PIKFYVE suppressing antisense oligonucleotide treatment for FTD Project Summary Frontotemporal dementia (FTD) is a complex disease that results from many diverse genetic etiologies. There are no drugs that slow the progression of FTD. Although therapeutic strategies that target specific causal mutations (e.g. C9ORF72 ASOs) may prove effective against individual forms of FTD, these approaches cannot address the vast majority of cases that have unknown genetic etiology. Moreover, given the large number of different genes that likely contribute to FTD and the fact that each genetic form is relatively rare, this strategy may be difficult to implement for all cases. Thus, there is a pressing need for new therapeutic strategies that rescue multiple forms of FTD, particularly those with unknown genetic etiologies. 45% of FTD patients display cytosolic aggregates of TDP-43 in cortical neurons, while another 45% harbor tau aggregates. Studies suggest that these neuronal TDP-43 and tau aggregates drive neurodegeneration. Thus, to identify new therapeutic targets for FTD, we used cellular reprogramming to generate induced cortical neurons (iNs) from C9ORF72 FTD patients, who display TDP-43 aggregates, as well as MAPT FTD patients, who harbor tau aggregates. We then performed chemical screens to identify targets that rescue the degeneration of both C9ORF72 and MAPT FTD iNs. Inhibitors of PIKFYVE kinase were among the most potent compounds on both C9ORF72 and MAPT FTD iNs. Antisense oligonucleotide (ASO)-mediated suppression of PIKFYVE confirmed that blocking PIKFYVE activity rescues FTD iN survival. In contrast to small molecules, antisense oligonucleotides (ASOs) provide a facile approach to targeting the CNS because they can be injected directly into the spinal cord, achieve sustained target engagement throughout the CNS, and are less likely to cause peripheral toxicity. Thus, we are pursuing ASO-mediated suppression of PIKFYVE as a therapeutic approach for diverse forms of ALS. We have screened hundreds of human PIKFYVE ASOs and identified ten lead ASOs with potent PIKFYVE knockdown in vitro . We have tested hundreds of human PIKFYVE ASOs and identified three promising leads for development. The objective of this Direct to Phase 2 proposal is to further characterize the efficacy of PIKFYVE suppression, and the safety of the lead ASOs to select a bona fide development candidate for advancement in GLP toxicity studies. Our discovery of secretory autophagy as a therapeutic approach in neurodegeneration is high impact for the field because activating the proteasome and autophagy has had mixed results in neurodegeneration models.