Determining reference ranges for a novel light emitting diode (LED) phototest device
Erythema reaction of non-photosensitive individuals to various wavelengths of LED light
The study will consist of the following interventions and assessments: Visit 1 Screening/inclusion & exclusion/informed consent Visit 2 (Day 0) Up to 30 days from Visit 1 1. Non-invasive reflectance measurement of the back for an objective measurement of skin colour 2. Back irradiated with the LED-based phototest device at various wavelengths and doses 3. Back irradiated with an irradiation monochromator, which is our routine clinical phototest equipment, at various wavelengths and doses 4. Visual observation of the test sites for urticaria, for up to 30 minutes Visit 3 (Day 1) +1 day from Day 0 1. Visual observation of MED on skin around 24 hours post initial exposure. Recording of skin response. 2. Further irradiation of the back with the LED-based phototest device. Doses delivered will be between the MED and the highest No-Response Dose (NRD) 3. Further irradiation of the back with the irradiation monochromator. Doses delivered will be between the MED and the highest No-Response Dose (NRD) 4. Non-invasive reflectance measurement may be taken to assess any non-visual changes 5. If no MED following Day 0 irradiation then higher doses may be delivered Visit 4 +1 (Day 2) day from Day 1 1. Visual observation of MED on skin @ around 24 hours post Day 1 exposure. Recording of skin response 2. Non-invasive reflectance measurement may be taken to assess any non-visual changes 3. If no MED following Day 1 irradiation, then further irradiation of the back may occur with the LED-based phototest device and/or irradiation monochromator at higher doses than delivered on Day 1 Visit 5 (Day 3), if required, +1 day from Day 2 1. Visual observation of MED on skin @ around 24 hours post Day 2 exposure. Recording of skin response 2. Non-invasive reflectance measurement may be taken to assess any non-visual changes
1. Healthy persons with no clinically significant abnormality identified by participant reported medical history, in particular no evidence of abnormal photosensitivity 2. Adult males and females, >18 years only 3. Capable of giving informed consent 4. Able to understand and comply with protocol requirements and timetables, instructions and protocol-stated restrictions
1. Any photosensitising medication or supplement (systemic or topically applied to the test area) within 14 days prior to testing 2. Insufficient clear, untanned, unaffected skin on the back to allow minimal erythema dose (MED) testing 3. Participation in a clinical study involving administration of an investigational drug (new chemical entity/non-licensed drug) or in a clinical study involving administration of a marketed drug within the past 3 months 4. Known to have abnormal photosensitivity 5. Pregnant or breastfeeding 6. Use of self-tanning products on the back (test area) in the preceding 2 weeks 7. Sunbed exposure or natural sunlight-induced sunburn or tan on the back (test area) acquired within the four weeks prior to recruitment 8. Immunosuppression due to medications (such as organ transplant recipient) or disease (including HIV or haematological malignancy) 9. History of skin cancer, not including basal cell carcinoma (BCC) 10. History of malignancy not curatively treated at least 5 years before screening visit, with exception of BCC or cervical carcinoma in situ, which may have been curatively treated within 1 year 11. History of current use of illegal or ‘recreational’ drugs 12. Any condition which, in the opinion of the investigator, might put the subject at risk by participating in this study