Inhibition of Non-histaminergic Pruritus Applied Using 3 Different Pruritogens

• Sponsor: Aalborg University (Other)
• Overall Status: Recruiting
• CT.gov ID: NCT04858360
• Collaborator: (none)
• Enrollment: 22
• Location: 1
• Arm: 1
• Anticipated Duration (Months): 10.5
• Patients Per Site Per Month: 2.1

Study Details

Study Description

Brief Summary

With this experiment, we want to use to investigate whether repeated application of EMLA cream as a tool to modulate non-histaminergic itching, which is produced using small needles from the plant mucuna pruriens (it is known that antihistamine does not attenuate this form of itch) and we want to compare the effect of short (1 hour) and prolonged (3 hours) application of EMLA. The sub-project takes place in 3 sessions over a period of 3 consecutive days (24 hours apart). All sessions will be identical.

Condition or Disease	Intervention/Treatment	Phase
Itch	Drug: Emla 1 hour; Drug: EMLA 3 hours; Other: Vehicle cream for 1 hour; Other: Vehicle cream for 3 hours; Other: Cowhage	N/A

Study Design

• Study Type: Interventional
• Anticipated Enrollment: 22 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Basic Science
• Official Title: Evaluation of the Effect of Repeated Administration of Topical Local Anaesthetic Mixture of Lidocaine and Prilocaine (EMLA) in a Model of Non-histaminergic Itch Induced by Cowhage.
• Actual Study Start Date: Nov 15, 2021
• Anticipated Primary Completion Date: Aug 1, 2022
• Anticipated Study Completion Date: Oct 1, 2022

Arms and Interventions

Arm

Intervention/Treatment

Experimental: Study group

Drug: Emla 1 hour; At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then one area will be pre-treated with cutaneous 2.5% lidocaine/2.5% prilocaine cream (EMLA cream) for 1 hour.; Drug: EMLA 3 hours; At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then one area will be pre-treated with cutaneous 2.5% lidocaine/2.5% prilocaine cream (EMLA cream) for 3 hours.; Other: Vehicle cream for 1 hour; At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then two area will be pre-treated with a vehicle cream for 1 h.; Other: Vehicle cream for 3 hours; At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then two area will be pre-treated with a vehicle cream for 3 h.; Other: Cowhage; Cowhage spicules are 1-2 mm in length and have a diameter of 1-3 μm. The spicules are inserted by gently rubbing 30-35 spicules into a 1 cm diameter skin area.

Outcome Measures

Primary Outcome Measures

1. Measuring itch intensity by computerized Visual Analog Scale Scoring [For 9 minutes]

   We will ask the subjects to rate the sensation of itch on a 100 mm VAS scale ranging from 0 to 100 where 0 indicates "no itch" and 100 indicates "worst itch imaginable

2. Measuring pain intensity by computerized Visual Analog Scale Scoring [For 9 minutes]

   We will ask the subjects to rate the sensation of pain on a 100 mm VAS scale ranging from 0 to 100 where 0 indicates "no pain" and 100 indicates "worst pain imaginable".

3. Superficial blood perfusion measurement [After 1 hour]

   Superficial blood perfusion is measured by a Speckle contrast imager

4. Superficial blood perfusion measurement [After 3 hours]

   Superficial blood perfusion is measured by a Speckle contrast imager

5. Superficial blood perfusion measurement [10 min after cowhage application]

   Superficial blood perfusion is measured by a Speckle contrast imager

6. Measuring Alloknesis [After 1 hour]

   Alloknesis sensation is measured using a standardized sensory brush exerting a force of 200 to 400 mN.

7. Measuring Alloknesis [After 3 hours]

   Alloknesis sensation is measured using a standardized sensory brush exerting a force of 200 to 400 mN.

8. Measuring Alloknesis [10 min after cowhage application]

   Alloknesis sensation is measured using a standardized sensory brush exerting a force of 200 to 400 mN.

9. Measuring Hyperknesis [After 1 hour]

   Hyperknesis is measured by using mildly pruritic, non-painful von Frey nylon filaments of a predetermined intensity (generally 5-30 miliNewton of force).

10. Measuring Hyperknesis [After 3 hours]

    Hyperknesis is measured by using mildly pruritic, non-painful von Frey nylon filaments of a predetermined intensity (generally 5-30 miliNewton of force).

11. Measuring Hyperknesis [10 min after cowhage application]

    Hyperknesis is measured by using mildly pruritic, non-painful von Frey nylon filaments of a predetermined intensity (generally 5-30 miliNewton of force).

Secondary Outcome Measures

1. Measuring Erythema [After 1 hour]

   The onset of erythema is measured with a spectrometer (ColorMeter, DSM II; Cortex Technology, Hadsund, Denmark).

2. Measuring Erythema [After 3 hours]

   The onset of erythema is measured with a spectrometer (ColorMeter, DSM II; Cortex Technology, Hadsund, Denmark).

3. Measuring Erythema [10 min after cowhage application]

   The onset of erythema is measured with a spectrometer (ColorMeter, DSM II; Cortex Technology, Hadsund, Denmark).

4. Measuring Skin Pigmentation [After 1 hour]

   The onset of skin pigmentation is measured with a spectrometer (ColorMeter, DSM II; Cortex Technology, Hadsund, Denmark).

5. Measuring Skin Pigmentation [After 3 hours]

   The onset of skin pigmentation is measured with a spectrometer (ColorMeter, DSM II; Cortex Technology, Hadsund, Denmark).

6. Measuring Skin Pigmentation [10 min after cowhage application]

   The onset of skin pigmentation is measured with a spectrometer (ColorMeter, DSM II; Cortex Technology, Hadsund, Denmark).

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 60 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

• Healthy men and women

• 18-60 years

• 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 that may affect the results (e.g. neuropathy, muscular pain in the upper extremities, etc.).

• Lack of ability to cooperate

• Current use of medications that may affect the trial such as antihistamine medications or pain killers.

• Skin diseases

• Hypersensitivity to papaya and mango fruit, cashew nuts and rubber latex

• 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)

• Known history of anaphylactic shock, or local allergy (contact dermatitis) to lidocaine, prilocaine or other local anaesthetics of the amide type.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Aalborg University	Aalborg		Denmark	9220

Sponsors and Collaborators

• Aalborg University

Investigators

• Principal Investigator: Silvia lo Vecchio, Aalborg University

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Silvia Lo Vecchio, PhD, Assistant Professor, Aalborg University
• ClinicalTrials.gov Identifier: NCT04858360
• Other Study ID Numbers: N-20200073 1st sub-project
• First Posted: Apr 26, 2021
• Last Update Posted: Jul 20, 2022
• Last Verified: Jul 1, 2022

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No
• Additional relevant MeSH terms: Lidocaine, Prilocaine Drug Combination

Study Results

No Results Posted as of Jul 20, 2022