Combination of adrenergic agonist and tricyclo-alkylamine for relieving chronic pain without adverse side effects
申请人:——
公开号:US20020177592A1
公开(公告)日:2002-11-28
This invention discloses that a combination of two drugs, from two different and previously unrelated categories, provides effective and long-lasting relief from neuropathic pain. Both drugs can be taken orally, in a convenient, painless, non-invasive manner that does not require injections. One drug in this combination is an &agr;2 adrenergic agonist, exemplified by clonidine. The other drug in the pain-relieving combination has a tri-cyclo-alkyl-amine (TCAA) structure. At least some TCAA drugs have antagonist (receptor-blocking) activity at two entirely different classes of neuronal receptors: the muscarinic subclass of acetylcholine (ACh) receptors, and the NMDA subclass of glutamate receptors. Such drugs include ethopropazine, normally used as an anti-cholinergic drug, and desipramine, normally used as an anti-depressant. Tests by the Applicants have shown that at least some TCAA drugs can relieve neuropathic pain to a limited extent, but at the doses required to relieve pain, they cause adverse side effects, and any pain relief is relatively brief and short-lived. However, when a TCAA drug such as ethopropazine is administered together with an &agr;2 adrenergic agonist such as clonidine, these drugs mutually potentiate one another's neuropathic pain-relieving action, and provide potent and sustained neuropathic pain relief, even when each agent is administered at a low dosage that is below its threshold for causing adverse side effects. Accordingly, this drug combination can provide safe and effective relief of neuropathic pain and possibly other types of chronic and/or intractable pain, at dosages which are so low that they do not pose serious risks of adverse side effects.
这项发明揭示了两种药物的组合,来自两个不同且先前无关的类别,能够有效且持久地缓解神经痛。这两种药物可以口服,以方便、无痛、非侵入性的方式服用,无需注射。这种组合中的一种药物是α2肾上腺素受体激动剂,以克隆啶为例。缓解疼痛的另一种药物具有三环烷基胺(TCAA)结构。至少一些TCAA药物在两个完全不同的类别的神经受体上具有拮抗(受体阻断)活性:乙酰胆碱(ACh)受体的肌样亚类和谷氨酸受体的NMDA亚类。这些药物包括依托普拉辛,通常用作抗胆碱药物,以及地西泮,通常用作抗抑郁药物。申请人的测试显示,至少一些TCAA药物可以在一定程度上缓解神经痛,但在缓解疼痛所需的剂量下,它们会引起不良副作用,而且任何疼痛缓解都相对短暂。然而,当像依托普拉辛这样的TCAA药物与像克隆啶这样的α2肾上腺素受体激动剂一起使用时,这些药物相互增强彼此的神经痛缓解作用,并提供强效且持久的神经痛缓解,即使每种药物在低剂量下也能实现,低剂量低于引起不良副作用的阈值。因此,这种药物组合可以在剂量非常低的情况下提供神经痛和可能其他类型的慢性和/或难治性疼痛的安全有效缓解,不会带来严重的不良副作用风险。