Repeated Open Application Test (ROAT) Study With Hydroperoxides of Linalool

Allergic Contact Dermatitis Clinical Trial

Official title:

Allergic Contact Dermatitis to Hydroperoxides of Linalool - a Repeated Open Application Test (ROAT) Study

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT05858723
• Other study ID #: H-23018400
• Status: Not yet recruiting
• Phase: N/A
• Start date: August 2023
• Est. completion date: July 2024

Study information

• Verified date: May 2023
• Source: National Allergy Research Center, Denmark
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Linalool is currently one of the most used fragrance substances in cosmetic and household products. Previous studies report a high prevalence (5.9-11.7%) of contact allergy to hydroperoxides of linalool (Lin-OOH)1.0% in pet. among patch tested patients. The optimal test concentration of Lin-OOH in patch tests is not known and requires further investigation. It is of great importance to establish the optimal test concentration and elicitation threshold of Lin-OOH to improve diagnosis and prevent development of Allergic Contact Dermatitis (ACD).

We want to mimic real-life exposure to Lin-OOH, by conducting a ROAT (Repeated Open Application Test) study, on 40 adult participants (20 patients with confirmed contact allergy to Lin-OOH, and 20 healthy participants) to low doses of Lin-OOH using a simulated "perfume", during a maximum of 21 days of exposure.

With this knowledge, we aim to:

1. Establish the optimal patch test concentration to diagnose ACD to Lin-OOH

2. In case of confirmed contact allergy, examine the threshold value for the development of ACD upon daily exposure to a simulated leave-on cosmetic product

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 40
• Est. completion date: July 2024
• Est. primary completion date: January 2024
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 110 Years

Eligibility

Allergic participants:

1. Inclusion criteria

• Positive (at least one reading) or doubtful patch test (at least two readings) result to hydroperoxides of Linalool within the last ten years

• Aged 18 years or older

• Received written and verbal information of the study

• Signed written consent form

2. Exclusion criteria

• Active eczema in test areas (volar forearms)

• Pregnancy or breast feeding

• Treatment with topical corticosteroids or other immune suppressants on/near test areas within two weeks prior to study start

• Systemic immune-suppressant treatment within seven days prior to study start

• UV exposure of test areas within three weeks prior to study start

• Unable to cooperate or communicate with the investigators

Healthy controls:

1. Inclusion criteria

• Aged 18 years or older

• Received written and verbal information of the study

• Signed written consent form

2. Exclusion criteria

• Known or possible contact allergy to hydroperoxides of Linalool

• Known contact allergy to other fragrance allergens

• Active eczema or other known relevant skin diseases

• Pregnancy or breast feeding

• Treatment with topical corticosteroids or other immune suppressants on/near test areas within four weeks prior to study start.

• Systemic immune-suppressant treatment within four weeks prior to study start.

• UV exposure of test areas within three weeks prior to study start.

• Participation in other clinical studies within four weeks prior to study start.

• Unable to cooperate or communicate with the investigators.

Related Conditions & MeSH terms

• Allergic Contact Dermatitis
• Dermatitis
• Dermatitis, Allergic Contact
• Dermatitis, Contact

Intervention

Diagnostic Test:
• ROAT
Repeated Open Application Test

Locations

Country	Name	City	State
n/a

Sponsors (1)

Lead Sponsor	Collaborator
National Allergy Research Center, Denmark

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Establish the optimal patch test concentration to diagnose allergic contact dermatitis to hydroperoxides of linalool via a Repeated Open Application Test	Establish the optimal patch test concentration to diagnose allergic contact dermatitis to hydroperoxides of linalool via Repeated Open Application Test	6 months
Primary	In case of confirmed contact allergy, examine the threshold value for the development of ACD upon daily exposure to a simulated leave-on cosmetic product	In case of confirmed contact allergy, examine the threshold value for the development of ACD upon daily exposure to a simulated leave-on cosmetic product	6 months
Secondary	The Lin-OOH chemicals can penetrate the skin barrier and reside in the local skin tissue	Chemical analysis of skin punch biopsies from the exposed skin of the patients' lower back: time of flight secondary ion mass spectrometry (ToF-SIMS) analysis of Lin-OOH in the skin.	12 months