Low Dose Exposure to Oxidized R-limonene - A Repeated Open Application Test (ROAT) Study

Herlev and Gentofte Hospital

Status: Completed

Conditions: Allergic Contact Dermatitis Due to Cosmetics

Treatments: Other: ROAT with oxidized R-limonene at 1%, 0.3% and 0.1%; Other: ROAT with oxidized R-limonene at 1%

Study type: Interventional

Funder types: Other

Identifiers

NCT03313232

HGH-2017-017

Details and patient eligibility

About

This study evaluates the clinical and molecular effect of daily exposure to low doses of the fragrance contact allergen oxidized R-limonene. Three groups of participants are included: 1) Patients with a previous positive patch test to oxidized R-Limonene, 2) patients with a previous doubtful patch test to oxidized R-limonene and 3) healthy controls with no contact allergy to oxidized R-limonene

Enrollment: 48 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Positive patch test (at least one reading) or doubtful patch test (at least two readings) to oxidized R-limonene 3% pet. (with 0.33% hydroperoxides content) according to international guidelines, within the last five years.
• Aged 18 years or older
• Received written and verbal information on the study.
• Signed written consent form.

Exclusion criteria

• Active eczema in test areas.
• 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.

Trial design

Primary purpose: Diagnostic

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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48 participants in 3 patient groups

Fragrance allergic patients

Experimental group

Description:

Patients with a previous positive patch test to oxidized R-Limonene. Patients will have an initial patch test dilution series with oxidized R-limonene performed on the back followed by twice daily exposure to oxidized R-limonene at three different concentrations and a vehicle control on the forearms for up to three weeks.

Treatment:

Other: ROAT with oxidized R-limonene at 1%, 0.3% and 0.1%

Possible fragrance allergic patients

Experimental group

Description:

Patients with a previous doubtful patch test to oxidized R-limonene. Patients will have an initial patch test dilution series with oxidized R-limonene performed on the back followed by twice daily exposure to oxidized R-limonene at three different concentrations and a vehicle control on the forearms for up to three weeks.

Treatment:

Other: ROAT with oxidized R-limonene at 1%, 0.3% and 0.1%

Healty controls

Experimental group

Description:

Healthy controls with no contact allergy to oxidized R-limonene. Healthy controls will have en initial diagnostic patch test with oxidized R-limonene performed followed by twice daily exposure to oxidized R-limonene at one concentration and a vehicle control on the forearms for up to three weeks.

Treatment:

Other: ROAT with oxidized R-limonene at 1%