Characterization of the Toll-like Receptor 7-agonist Imiquimod 3.75% As a New Surrogate Model of Itch
试验速览
- 阶段
- 不适用
- 状态
- 撤回
- 发起方
- 试验地点
- 1
- 主要终点
- Superficial blood perfusion by by a Speckle contrast imager (FLPI, Moor Instruments, England).
研究概览
简要总结
The aim of this research project is to design a new model of human itch by application of Zyclara cream. Further, the aim is to characterize the model and to verify if the mechanism of action of imiquimod follows the histaminergic or non-histaminergic pathway by using the anti-histamine drug doxepin. The last goal is to evaluate the interaction between the activation of TLR7 receptor and the activation of TRPA1 and TRPM8 receptors, which are two of the most important receptors involved in the transduction of noxious stimuli, and to evaluate to which extent these three channel populations functionally overlap.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 18 Years 至 60 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy men and women
- •18-60 years
- •Speak and understand English
排除标准
- •Pregnancy or lactation
- •Drug addiction defined as any use of cannabis, opioids or other drugs
- •Previous or current neurologic, musculoskeletal or mental illnesses
- •Lack of ability to cooperate
- •Current use of medications that may affect the trial
- •Skin diseases
- •Consumption of alcohol or painkillers 24 hours before the study days and between these
- •Acute or chronic pain
- •Participation in other trials within 1 week of study entry (4 weeks in the case of pharmaceutical trials)
研究组 & 干预措施
Zyclara/vehicle
All subjects will be treated with Zyclara cream (Imiquimod 3.75%) and vehicle.
干预措施: Zyclara 3.75 % Topical Cream (Drug)
Zyclara/Doxepin
All subjects will be treated with the topical antihistamine cream (Prudoxin, containing 5% doxepin hydrochloride, Healthpoint, San Antonio, TX) or a placebo cream. After removal, subjects will be treated with Zyclara cream
干预措施: Zyclara 3.75 % Topical Cream (Drug)
Zyclara/Doxepin
All subjects will be treated with the topical antihistamine cream (Prudoxin, containing 5% doxepin hydrochloride, Healthpoint, San Antonio, TX) or a placebo cream. After removal, subjects will be treated with Zyclara cream
干预措施: Prudoxin (Drug)
Zyclara/Histamine/Cowage
All subjects will be treated with Zyclara cream, vehicle cream, histamine and cowhage
干预措施: Zyclara 3.75 % Topical Cream (Drug)
Zyclara/Histamine/Cowage
All subjects will be treated with Zyclara cream, vehicle cream, histamine and cowhage
干预措施: Histamine (Other)
Zyclara/Histamine/Cowage
All subjects will be treated with Zyclara cream, vehicle cream, histamine and cowhage
干预措施: Cowhage (Other)
Zyclara/L-menthol/trans-cinnamaldehyde
All subjects will be treated with Zyclara cream (Imiquimod 3.75%) and vehicle. After removal, subjects will be treated with L/menthol and trans-cinnamaldehyde
干预措施: Zyclara 3.75 % Topical Cream (Drug)
Zyclara/L-menthol/trans-cinnamaldehyde
All subjects will be treated with Zyclara cream (Imiquimod 3.75%) and vehicle. After removal, subjects will be treated with L/menthol and trans-cinnamaldehyde
干预措施: L-menthol (Other)
Zyclara/L-menthol/trans-cinnamaldehyde
All subjects will be treated with Zyclara cream (Imiquimod 3.75%) and vehicle. After removal, subjects will be treated with L/menthol and trans-cinnamaldehyde
干预措施: Trans-cinnamaldehyde (CA) (Other)
结局指标
主要结局
Superficial blood perfusion by by a Speckle contrast imager (FLPI, Moor Instruments, England).
时间窗: Change from baseline, to maximum 19 days after intervention
Two pictures will be taken: one with the sensor placed approximately 35 cm above the induction area and one with the sensor placed approximately 20 cm above the induction area.
Trans-epidermal Water Loss (TEWL)
时间窗: Change from baseline, to maximum 19 days after intervention
a 2x2 cm hollow probe with two small humidity gauges and two thermometers is placed lightly on the skin for 10-25 seconds. These establish a precise humidity gradient in a 2 cm vicinity of the skin, representative for the point-loss of water though the epidermis.
Neurogenic Inflammatory Response and Pigmentation
时间窗: Change from baseline, to maximum 19 days after intervention
treatment will be measured with a spectrometer designed for cutaneous use (ColorMeter, DSM II; Cortex Technology, Hadsund, Denmark).
Measuring Alloknesis
时间窗: Change from baseline, to maximum 19 days after intervention
Alloknesis is measured by using mildly pruritic, non-painful von Frey nylon filaments of a predetermined intensity (generally 5-30 miliNewton of force).
Thermal measurements (cold and warm detection thresholds, cold and heat pain thresholds)
时间窗: Change from baseline, to maximum 19 days after intervention
The tests for thermal sensation will all be conducted using a PATHWAY ATS (Medoc Ltd, Israel) thermal sensory testing device
Measurement of Pain to Supra-threshold Heat Stimuli
时间窗: Change from baseline, to maximum 19 days after intervention
The test will all be conducted using a PATHWAY ATS (Medoc Ltd, Israel) thermal sensory testing device
Measurement of Mechanical Detection Thresholds, Mechanical Pain Threshold and sensitivity
时间窗: Change from baseline, to maximum 19 days after intervention
These tests are conducted using a set of 20 different von Frey hairs (North Coast Medical, Gilroy, CA) with exerted forces ranging from .008g to 300g.
次要结局
- Measurement of Itch rating by Computerized Visual Analog Scale Scoring(Change from baseline, to maximum 19 days after intervention)
- Measurement of pain rating by Computerized Visual Analog Scale Scoring(Change from baseline, to maximum 19 days after intervention)
研究者
Silvia Lo Vecchio
Principal Investigator
Aalborg University