Adverse events in gabapentin arm.

Background
To estimate the effects on pain of two medications (low-dose naltrexone and gabapentin) compared to placebo among people with HIV (PWH) with heavy alcohol use and chronic pain.
Methods
We conducted a pilot, randomized, double-blinded, 3-arm study of PWH with chronic pain and past-year heavy alcohol use in 2021. Participants were recruited in St. Petersburg, Russia, and randomized to receive daily low-dose naltrexone (4.5mg), gabapentin (up to 1800mg), or placebo. The two primary outcomes were change in self-reported pain severity and pain interference measured with the Brief Pain Inventory from baseline to 8 weeks.
Results
Participants (N = 45, 15 in each arm) had the following baseline characteristics: 64% male; age 41 years (SD±7); mean 2 (SD±4) heavy drinking days in the past month and mean pain severity and interference were 3.2 (SD±1) and 3.0 (SD±2), respectively. Pain severity decreased for all three arms. Mean differences in change in pain severity for gabapentin vs. placebo, and naltrexone vs. placebo were -0.27 (95% confidence interval [CI] -1.76, 1.23; p = 0.73) and 0.88 (95% CI -0.7, 2.46; p = 0.55), respectively. Pain interference decreased for all three arms. Mean differences in change in pain interference for gabapentin vs. placebo, and naltrexone vs. placebo was 0.16 (95% CI -1.38, 1.71; p = 0.83) and 0.40 (95% CI -1.18, 1.99; p = 0.83), respectively.
Conclusion
Neither gabapentin nor low-dose naltrexone appeared to improve pain more than placebo among PWH with chronic pain and past-year heavy alcohol use.
Clinical trial registration
ClinicalTrials.gov (NCT4052139).

研究背景：本研究旨在评估相较于安慰剂，两种药物（低剂量纳曲酮与加巴喷丁）对合并重度饮酒与慢性疼痛的人类免疫缺陷病毒感染者（People With HIV, PWH）的疼痛改善效果。
研究方法：本研究于2021年开展一项针对合并慢性疼痛与过去一年重度饮酒史的PWH的先导性、随机双盲三臂临床试验。研究于俄罗斯圣彼得堡招募受试者，将其随机分配至每日服用低剂量纳曲酮（4.5mg）、加巴喷丁（最高1800mg）或安慰剂组。两项主要结局指标为从基线至8周时，受试者自我报告的疼痛强度及疼痛干扰的变化情况，其中疼痛干扰通过简明疼痛量表（Brief Pain Inventory, BPI）进行评估。
研究结果：本研究共纳入45名受试者，每组各15人。受试者基线特征如下：男性占比64%；平均年龄41岁（标准差±7，Standard Deviation, SD）；过去一个月内平均重度饮酒天数为2天（SD±4）；平均疼痛强度与疼痛干扰评分分别为3.2（SD±1）与3.0（SD±2）。三组受试者的疼痛强度均有所下降。加巴喷丁组相较于安慰剂组、纳曲酮组相较于安慰剂组的疼痛强度变化平均差值分别为-0.27（95%置信区间[CI]：-1.76~1.23；p=0.73）与0.88（95%置信区间[CI]：-0.7~2.46；p=0.55）。三组受试者的疼痛干扰均有所下降。加巴喷丁组相较于安慰剂组、纳曲酮组相较于安慰剂组的疼痛干扰变化平均差值分别为0.16（95%置信区间[CI]：-1.38~1.71；p=0.83）与0.40（95%置信区间[CI]：-1.18~1.99；p=0.83）。
研究结论：对于合并慢性疼痛与过去一年重度饮酒史的PWH而言，加巴喷丁与低剂量纳曲酮均未展现出优于安慰剂的疼痛改善效果。
临床试验注册：ClinicalTrials.gov（登记号：NCT4052139）。