Condition category
Skin and Connective Tissue Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Background and study aims
Polymorphic light eruption (PLE) is the most common allergy to the sun. It affects 18% of the population of northern Europe. A itchy, but none scarring, skin rash occurs around 4-6 hours after exposure to the sun. Very little is known about what causes PLE. It has been suggested that an allergen formed in or on the skin upon sun exposure is responsible for the rash, but this photoallergen has not yet been identified. Other researchers believe that PLE patients are less likely to suppress the effects of the sun on the skin compared to healthy people. One of the skin's most important roles is to form a barrier between the inside of the body and the environment outside. This barrier is made up of special proteins, which act to prevent water being lost from the skin as well as pathogens entering to the body. Recent work in our laboratory has shown that specific barrier forming proteins of the skin are altered in PLE. A damaged barrier may be more prone to movement of photoallergens through the skin leading to the cause of PLE symptoms. The aim of this study is to investigate the function of the skin barrier in PLE patients before and after exposure to ultraviolet light, and to test the effect of barrier reinforcing molecules on the skin barrier.

Who can participate?
Healthy volunteers or PLE patients who are white caucasians and between 30-60 years old

What does the study involve?
Participants have their sunburn threshold tested on their upper buttock skin. Small skin biopsies are taken from areas exposed to UV light and from unexposed skin for laboratory analysis of skin barrier function. Skin water loss is measured from UV-exposed and unexposed skin.

What are the possible benefits and risks of participating?
Participants do not benefit directly from taking part in this study, but the information gathered will lead to a further understanding of the cause of PLE.

Where is the study run from?
This study is being performed in the Photobiology Unit, Salford Royal NHS Foundation Trust and the dermatology research laboratories at the University of Manchester (UK)

When is the study starting and how long is it expected to run for?
February 2014 to August 2015

Who is funding the study?
British Skin Foundation (UK)

Who is the main contact?
Dr Mark Farrar

Trial website

Contact information



Primary contact

Dr Mark Farrar


Contact details

Photobiology Unit
Hope Hospital
Stott Lane
M6 8HD
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

A non-randomised trial investigating the barrier function and barrier forming proteins of the skin in polymorphic light eruption


Study hypothesis

1. The barrier function of the skin is compromised in polymorphic light eruption
2. Abnormal tight junction protein expression is related to skin barrier defects in polymorphic light eruption
3. The barrier can be improved using food-derived molecules

Ethics approval

NRES Committee North West -– Greater Manchester West; 13/01/2014, ref. 13/NW/0797

Study design

Non-randomised; Interventional and Observational; Design type: Not specified, Clinical Laboratory Study

Primary study design


Secondary study design

Non randomised study

Trial setting


Trial type


Patient information sheet

Details of who to contact can be found at:


Topic: Dermatology; Subtopic: Skin (all Subtopics); Disease: Dermatology


Measurements of water loss of the skin will be taken from sun protected buttock skin. To assess sunburn threshold, standard minimal erythemal dose (MED) testing will be performed where another area of photoprotected buttock skin will be exposed to twelve controlled doses of UV with each exposure site being approximately 1cm in diameter. Twenty-four hours later, water loss measurements will be repeated and erythema (redness) assessed.

Intervention type



Not Applicable

Drug names

Primary outcome measure

Barrier forming protein function. Timepoint(s): 24h

Secondary outcome measures

Not provided at time of registration

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Healthy volunteers or PLE patients that have reached diagnostic criteria for PLE (through patient questionnaire and clinical diagnosis)
2. White Caucasians of photoreactive skin type I-III
3. Female (not pregnant) or male 30-60 years
4. Volunteers giving written informed consent

Participant type

Healthy volunteer

Age group




Target number of participants

Planned Sample Size: 50; UK Sample Size: 50; Description: To account for drop out rate study team anticipate recruitment between 40-60 participants.

Participant exclusion criteria

1. People who smoke
2. People with other conditions exacerbated by light
3. People taking photoactive medication
4. People unable to complete the visit requirements of the protocol
5. Inability to comply with all requirements of the protocol
6. History of sunbathing or artificial UV exposure in the previous 3 months
7. History of skin cancer

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Hope Hospital
M6 8HD
United Kingdom

Sponsor information


University of Manchester (UK)

Sponsor details

Oxford Road
M13 9PL
United Kingdom

Sponsor type




Funder type


Funder name

British Skin Foundation; Grant Codes: S1004

Alternative name(s)


Funding Body Type

private sector organisation

Funding Body Subtype

Trusts, charities, foundations (both public and private)


United Kingdom

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

12/08/2020: No publications found, verifying study status with principal investigator. 14/09/2017: No publications found, verifying study status with principal investigator.