Effects of High-concentration Topical Capsaicin on Histaminergic and Non-histaminergic Itch

Phase 1

Completed

• Conditions: Pruritus
• Interventions: Drug: Capsaicin 24 Hours; Drug: Capsaicin 1 Hour; Other: Qutenza Demo Patch

• Registration Number: NCT02769910
• Lead Sponsor: Hjalte Holm Andersen

Brief Summary

The purpose of this project is to investigate the effect of capsaicin-induced neurogenic inflammation with three different intensities on itch subsequently induced by histamine and cowhage. The hypothesis is that capsaicin-induced pre-established neurogenic inflammation significantly increases susceptibility to itch provocations with cowhage and histamine.

Detailed Description

Not available

Study Timeline

• Study Start: 2016-05
• Study First Submitted: 2016-05-10
• Study First Submitted QC: 2016-05-11
• Study First Posted: 2016-05-12
• Primary Completion: 2016-07
• Study Completion: 2016-07
• Status Verified: 2016-11
• Last Update Submitted: 2016-11-19
• Last Update Posted: 2016-11-22

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 16

Inclusion Criteria

• Healthy men and women
• 18-60 years
• Caucasian descent
• Speak and understand English

Exclusion Criteria

• 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
• Moles or tattoos in the area to be irradiated
• Exposure of the irradiated area to UV radiation (e.g., sun) 48 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)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Cowhage	Capsaicin 24 Hours	Cowhage is used to induce non-histaminergic itch on the volar forearm at the locations treated with Capsaicin 24 Hours, Capsaicin 1 Hours and Qutenza Demo Patch.
Cowhage	Qutenza Demo Patch	Cowhage is used to induce non-histaminergic itch on the volar forearm at the locations treated with Capsaicin 24 Hours, Capsaicin 1 Hours and Qutenza Demo Patch.
Histamine	Capsaicin 24 Hours	Histamine is used to induce histaminergic itch on the volar forearm at the locations treated with Capsaicin 24 Hours, Capsaicin 1 Hour and Qutenza Demo Patch.
Histamine	Qutenza Demo Patch	Histamine is used to induce histaminergic itch on the volar forearm at the locations treated with Capsaicin 24 Hours, Capsaicin 1 Hour and Qutenza Demo Patch.
Cowhage	Capsaicin 1 Hour	Cowhage is used to induce non-histaminergic itch on the volar forearm at the locations treated with Capsaicin 24 Hours, Capsaicin 1 Hours and Qutenza Demo Patch.
Histamine	Capsaicin 1 Hour	Histamine is used to induce histaminergic itch on the volar forearm at the locations treated with Capsaicin 24 Hours, Capsaicin 1 Hour and Qutenza Demo Patch.

Primary Outcome Measures

Name	Time	Method
Itch intensity	Assessed continuously at 0-10 minutes following itch provocation	Rating of the perceived itch intensity on a visual analogue scale (VAS) App (Aalborg University) as displayed on a tablet computer with a sample rate of 1 Hz.

Secondary Outcome Measures

Name	Time	Method
Neurogenic inflammation	Assessed 11 minutes after itch provocation	Neurogenic inflammation in the treated area is assessed using full-field laser perfusion imaging (FLPI)
Wheal size	Assessed at 10 minutes following itch provocation	Histamine wheal size is assessed by measuring the longest diameter of the wheal with a ruler, followed by measuring the orthogonal diameter. The mean of these diameters will represent the wheal size in diameter, reported in mm.
Pain intensity	Assessed continuously at 0-10 minutes following itch provocation	Rating of the perceived pain intensity on a visual analogue scale (VAS) App (Aalborg University) as displayed on a tablet computer with a sample rate of 1 Hz.
Changes in sensitivity to touch-evoked itch	Assessed before, and at 12-15 minutes following itch provocation	Three von Frey filaments are applied to the test area before and after itch provocation. Subjects report three NRS scores ('0-10', 'No itch-Worst imaginable itch') for itch induced by von Frey stimulation. Change is calculated by subtracting baseline mean from post-provocation mean NRS scores.
Pain during capsaicin application	24 hours after first application of capsaicin patch	Peak and average numerical rating scale (NRS) scores ('0-10, 'no pain-worst imaginable pain') are reported by subjects for each patch.

Trial Locations

Locations (1)

SMI; 🇩🇰 Aalborg, NJ, Denmark