Neuroscience Drug Discovery, Ionis Pharmaceuticals Inc, Carlsbad, CA, USA.
Pain. 2018 Jan;159(1):139-149. doi: 10.1097/j.pain.0000000000001074.
There is an urgent need for better treatments for chronic pain, which affects more than 1 billion people worldwide. Antisense oligonucleotides (ASOs) have proven successful in treating children with spinal muscular atrophy, a severe infantile neurological disorder, and several ASOs are currently being tested in clinical trials for various neurological disorders. Here, we characterize the pharmacodynamic activity of ASOs in spinal cord and dorsal root ganglia (DRG), key tissues for pain signaling. We demonstrate that activity of ASOs lasts up to 2 months after a single intrathecal bolus dose. Interestingly, comparison of subcutaneous, intracerebroventricular, and intrathecal administration shows that DRGs are targetable by systemic and central delivery of ASOs, while target reduction in the spinal cord is achieved only after direct central delivery. Upon detailed characterization of ASO activity in individual cell populations in DRG, we observe robust target suppression in all neuronal populations, thereby establishing that ASOs are effective in the cell populations involved in pain propagation. Furthermore, we confirm that ASOs are selective and do not modulate basal pain sensation. We also demonstrate that ASOs targeting the sodium channel Nav1.7 induce sustained analgesia up to 4 weeks. Taken together, our findings support the idea that ASOs possess the required pharmacodynamic properties, along with a long duration of action beneficial for treating pain.
目前,全球有超过 10 亿人受到慢性疼痛的影响,对于慢性疼痛的治疗存在迫切的需求。反义寡核苷酸(ASO)已被证明可成功治疗脊髓性肌萎缩症(一种严重的婴儿神经疾病)患儿,目前已有多种 ASO 正在临床试验中针对各种神经疾病进行测试。在此,我们研究了 ASO 在脊髓和背根神经节(DRG)中的药效学活性,这些是疼痛信号的关键组织。结果表明,单次鞘内推注后,ASO 的活性可持续长达 2 个月。有趣的是,皮下、脑室内和鞘内给药的比较表明,DRG 可通过全身和中枢递送来靶向 ASO,而只有直接中枢递药才能实现脊髓内的靶标减少。在对 DRG 中单个细胞群体中的 ASO 活性进行详细特征分析后,我们观察到所有神经元群体均有强大的靶标抑制作用,从而证实 ASO 可有效作用于参与疼痛传播的细胞群体。此外,我们还证实 ASO 具有选择性,不会调节基础疼痛感觉。我们还证明,靶向钠离子通道 Nav1.7 的 ASO 可诱导长达 4 周的持续镇痛。综上,我们的研究结果支持这样一种观点,即 ASO 具有所需的药效学特性和有利的长效作用,可用于治疗疼痛。