Subcutaneous Botulinum Toxin for Cutaneous Allodynia - Enriched Responder Trial
试验速览
- 阶段
- 不适用
- 状态
- 终止
- 入组人数
- 5
- 试验地点
- 1
- 主要终点
- Time to Analgesic Failure
研究概览
简要总结
Superficial injection of Botulinum toxin has been advocated for cosmetic purposes but has also been reported to be helpful for some pain conditions. The investigators have observed prolonged profound analgesia following subcutaneous superficial injection of Botulinum Toxin Type A (BTA) in patients with certain types of neuropathic pain. the investigators propose to study if addition of BTA extends pain relief compared to placebo when injected subcutaneously into areas of cutaneous allodynia (the property that a normally non-noxious stimulus is perceived as painful).
详细描述
Patients with post-herpetic neuralgia, complex regional pain syndrome, and post-surgical neuromatous pain patients have marked cutaneous allodynia. Touching their skin with normally non-painful stimuli results in pain. Injected local anesthetics are often effective in providing temporary relief. In the course of clinical practice the investigators have observed that a number of patients with cutaneous allodynia have had marked persistent benefit from subcutaneous injection of Botulinum toxin Type A.
Rather than killing targeted neurons, Botulinum toxin type A inhibits release of acetylcholine from cholinergic nerve terminals in a prolonged but ultimately reversible manner. Neuropathic pain and its hallmark allodynia are classically difficult to treat. Standard treatment with tricyclic antidepressants, anti-epileptic drugs, opiates and spinal cord stimulation is frequently disappointing leaving patients with refractory pain. Surgical or percutaneous ablation of involved nerves has fallen out of favor among many due to disappointing results.
A pilot study is needed to assess the efficacy of superficially injected Botulinum Toxin type A for treatment of cutaneous allodynia and spontaneous pain among patients with neuropathic pain.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 100 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Moderate to severe pain (greater than 2/10) of duration more than 6 months despite previous therapy, excluding botox injection
- •The patient exhibits at least 80% pain relief following injection of local anesthetic subcutaneously into scar as assessed by change in NRS
- •Patient reports more than 3 weeks of greater than 50% pain relief from previous botox injection
- •The patient reports the presence of hyperalgesia, allodynia, dysesthesia, or hypoesthesia surrounding the scar in the absence of the botox injection
- •Age 18-100
- •Ability to read, write, and converse in English, provide informed consent, and follow study procedures
排除标准
- •Any neuromuscular disorder such as myasthenia gravis, eaton lambert, muscular dystrophy
- •Any ongoing legal action related to their pain
- •Allergy to local anesthetics
- •Any ongoing disability claim
- •Currently being treated for any severe psychiatric disorder, including anxiety or depression
- •History of any adverse reaction to botulinum toxin
- •History of botulism
- •Untreated infection
- •Coagulopathy
- •(Females) - positive pregnancy test
- •Surgery in the last 6 months
研究组 & 干预措施
Placebo then Botox
Injection 1: Saline- Subcutaneous injection of saline into scar tissue Injection 2: Botulinum Toxin Type A- Patients receive a subcutaneous injection of Botulinum Toxin Type A into the scar tissue
干预措施: Botulinum Toxin Type A (Drug)
Placebo then Botox
Injection 1: Saline- Subcutaneous injection of saline into scar tissue Injection 2: Botulinum Toxin Type A- Patients receive a subcutaneous injection of Botulinum Toxin Type A into the scar tissue
干预措施: Saline (Drug)
Botox then Placebo
Injection 1: Botulinum Toxin Type A- Patients receive a subcutaneous injection of Botulinum Toxin Type A into the scar tissue Injection 2: Saline- Subcutaneous injection of saline into scar tissue
干预措施: Botulinum Toxin Type A (Drug)
Botox then Placebo
Injection 1: Botulinum Toxin Type A- Patients receive a subcutaneous injection of Botulinum Toxin Type A into the scar tissue Injection 2: Saline- Subcutaneous injection of saline into scar tissue
干预措施: Saline (Drug)
结局指标
主要结局
Time to Analgesic Failure
时间窗: Duration of trial (2-20 months, depending on how long pain relief lasts)
Participants completed the Pain Numeric Rating Scale everyday after the injections. Outcome measure represents the number of days before pain returned to baseline levels.
次要结局
- NRS Score Three Weeks After Injection(3 weeks after injection)
- Improvement in Psychosocial Function as Assessed by Outcomes as Dictated by the IMMPACT Guidelines(Duration of trial (2-20 months, depending on how long pain relief lasts))
研究者
Sean Mackey
Associate Professor
Stanford University