Backonja Miroslav, Wallace Mark S, Blonsky E Richard, Cutler Barry J, Malan Philip, Rauck Richard, Tobias Jeffrey
University of Wisconsin-Madison, Madison, WI 53792, USA.
Lancet Neurol. 2008 Dec;7(12):1106-12. doi: 10.1016/S1474-4422(08)70228-X. Epub 2008 Oct 30.
The limitations of current treatments for postherpetic neuralgia (PHN) have led to the investigation of localised, non-systemic alternatives. NGX-4010, a high-concentration (8%) capsaicin dermal patch, was developed to treat patients with neuropathic pain. We report the results of a randomised, double blind, 12-week study of the efficacy and safety of one application of NGX-4010 in patients with PHN.
In this multicentre, double-blind, parallel-group trial, 402 patients were randomly assigned to one 60-min application of NGX-4010 (640 microg/cm(2) [8% capsaicin]) or a low-concentration capsaicin control patch (3.2 microg/cm(2) [0.04% capsaicin]). Patients were aged 18-90 years, had had postherpetic neuralgia for at least 6 months, and had an average baseline numeric pain rating scale (NPRS) score of 3 to 9. The primary efficacy endpoint was percentage change in NPRS score from baseline to weeks two to eight. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00115310.
Patients who were randomly assigned to NGX-4010 (n=206) had a significantly greater reduction in pain during weeks two to eight than did patients who had the control patch (n=196). The mean changes in NPRS score were -29.6%vs -19.9% (difference -9.7%, 95% CI -15.47 to -3.95; p=0.001). 87 (42%) patients who received NGX-4010 and 63 (32%) controls had a 30% or greater reduction in mean NPRS score (odds ratio [OR] 1.56, 95% CI 1.03 to 2.37; p=0.03). The patients who had NGX-4010 had significant improvements in pain during weeks two to 12 (mean change in NPRS score -29.9%vs -20.4%, difference -9.5, -15.39 to -3.61; p=0.002). Transient blood pressure changes associated with changes in pain level were recorded on the day of treatment, and short-lasting erythema and pain at the site of application were common, self-limited, and generally mild to moderate in the NGX-4010 group and less frequent and severe in the controls.
One 60-min application of NGX-4010 provided rapid and sustained pain relief in patients with postherpetic neuralgia. No adverse events were associated with treatment except for local reactions at the site of application and those related to treatment-associated pain.
目前治疗带状疱疹后神经痛（PHN）的方法存在局限性，这促使人们对局部而非全身性的替代疗法进行研究。NGX - 4010是一种高浓度（8%）辣椒素皮肤贴片，用于治疗神经性疼痛患者。我们报告了一项针对PHN患者单次应用NGX - 4010的疗效和安全性的随机、双盲、为期12周的研究结果。
在这项多中心、双盲、平行组试验中，402例患者被随机分配接受单次60分钟的NGX - 4010（640微克/平方厘米[8%辣椒素]）或低浓度辣椒素对照贴片（3.2微克/平方厘米[0.04%辣椒素]）治疗。患者年龄在18 - 90岁之间，带状疱疹后神经痛至少持续6个月，基线数字疼痛评分量表（NPRS）平均得分在3至9分之间。主要疗效终点是从基线到第2至8周NPRS评分的变化百分比。分析采用意向性治疗。该试验已在ClinicalTrials.gov注册，编号为NCT00115310。
随机分配接受NGX - 4010治疗的患者（n = 206）在第2至8周的疼痛减轻程度显著大于接受对照贴片的患者（n = 196）。NPRS评分的平均变化为-29.6%对-19.9%（差异-9.7%，95%置信区间-15.47至-3.95；p = 0.001）。接受NGX - 4010治疗的87例（42%）患者和63例（32%）接受对照治疗的患者平均NPRS评分降低了30%或更多（优势比[OR] 1.56，95%置信区间1.03至2.37；p = 0.03）。接受NGX - 4010治疗的患者在第2至12周疼痛有显著改善（NPRS评分平均变化-29.9%对-20.4%，差异-9.5，-15.39至-3.61；p = 0.002）。治疗当天记录到与疼痛水平变化相关的短暂血压变化，NGX - 4010组应用部位出现短暂红斑和疼痛较为常见，为自限性，一般为轻至中度，对照组则较少见且程度较轻。
单次60分钟应用NGX - 4010可为带状疱疹后神经痛患者提供快速且持续的疼痛缓解。除了应用部位的局部反应以及与治疗相关疼痛相关的反应外，未发现与治疗相关的不良事件。
