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Study on 5-Fluorouracil and Calcipotriol for Treating Actinic Keratosis in Patients

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the treatment of Actinic Keratosis, a skin condition caused by long-term sun exposure that can lead to rough, scaly patches on the skin. The study will compare two treatments: a combination of 5-Fluorouracil and Calcipotriol, and 5-Fluorouracil alone. 5-Fluorouracil is a cream used to treat skin conditions by stopping the growth of abnormal cells, while Calcipotriol is an ointment that helps regulate skin cell production.

The purpose of the study is to determine if the combination treatment is as effective as using 5-Fluorouracil alone over a period of four weeks. Participants will apply the treatments to the affected areas of their skin. The study will last for a total of 12 months, with follow-up checks to see how well the treatments have worked. The main goal is to achieve a significant reduction in the number of Actinic Keratosis lesions, which are the rough patches on the skin.

Throughout the study, participants will be monitored to see how their skin responds to the treatments. The effectiveness of the treatments will be assessed by the reduction in the number of skin lesions, and any side effects will be recorded. The study will also look at the overall satisfaction of participants with their treatment and any changes in their quality of life. This research aims to provide valuable information on the best treatment options for managing Actinic Keratosis.

The research process

The trial runs in 7 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, eligibility is confirmed based on specific criteria such as age, diagnosis of actinic keratosis, and the number of lesions in a defined area.

  2. Step 2

    Treatment phase

    The treatment involves the application of two medications: Efudix 5% cream containing fluorouracil and Calcipotriol Ointment 50 micrograms/g. These are applied topically, meaning directly onto the skin.

    The treatment duration varies: one group receives a combination of both medications for four or six days, while another group receives only the fluorouracil cream for four weeks.

  3. Step 3

    Post-treatment evaluation at 3 months

    Three months after completing the treatment, an evaluation is conducted to assess the reduction in actinic keratosis lesions. Success is defined as a reduction of 75% or more in the number of lesions.

    Additional assessments include the complete clearance of lesions, changes in the severity index, recurrence rates, and any adverse effects experienced.

  4. Step 4

    Post-treatment evaluation at 12 months

    Twelve months post-treatment, another evaluation is performed to determine the long-term success of the treatment, again looking for a 75% reduction in lesions.

    Further assessments include complete clearance of lesions, recurrence rates, need for retreatment, and patient satisfaction with the treatment.

  5. Step 5

    Quality of life assessment

    Quality of life is measured using the Skindex-17 questionnaire at baseline, one week after treatment, and at 3 and 12 months post-treatment.

  6. Step 6

    Treatment adherence

    Adherence to the treatment regimen is monitored, with complete adherence being a key measure of success.

  7. Step 7

    Exploratory endpoint

    An exploratory endpoint involves assessing the long-term probability of developing a condition known as cSCC over a three-year period.

Who can join the trial?

6 criteria

  • Must be an adult over 18 years old.
  • Must have a diagnosis of Actinic Keratosis (AK) by a dermatologist. This is a skin condition caused by sun exposure.
  • The diagnosis should be in one or more of the following areas: face, ears, balding scalp, neck, shawl area (including the sun-exposed chest area), or upper arms.
  • Must have at least 4 AK lesions in a treatment area that is no larger than 100 square centimeters. A lesion is a small area of skin that is different from the surrounding skin.
  • The AK lesions should be classified as Olsen grade I-III. This is a way to describe the severity of the lesions.
  • Both men and women can participate.

Who cannot join the trial?

9 criteria

  • Patients who are not within the specified age range for the study.
  • Patients who are part of a vulnerable population, which means they might need special protection or care.
  • Patients who do not have the medical condition being studied, which is Actinic Keratosis. This is a skin condition caused by too much sun exposure, leading to rough, scaly patches on the skin.
  • Patients who cannot follow the study's treatment plan or procedures.
  • Patients who have other medical conditions that might interfere with the study or its results.
  • Patients who are currently participating in another clinical trial.
  • Patients who have allergies or reactions to the study medications, which include 5-Fluorouracil and calcipotriol. These are medications used to treat skin conditions.
  • Patients who are pregnant or breastfeeding, as the study may not be safe for them or their babies.
  • Patients who have had recent treatments or surgeries that might affect the study's outcomes.
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Investigated drugs

  • 5-Fluorouracil

    is a medication used in this trial to treat actinic keratosis, a skin condition caused by sun damage. It works by interfering with the growth of abnormal skin cells, helping to reduce the number of lesions. In this study, it is used both alone and in combination with another medication to evaluate its effectiveness.

  • Calcipotriol

    is a form of vitamin D used in combination with 5-Fluorouracil in this trial. It helps to enhance the effect of 5-Fluorouracil by promoting the normal growth and development of skin cells. The combination aims to improve treatment outcomes for patients with actinic keratosis.

What is already known about the treatment

  • 5-Fluorouracil

    This medication is typically applied topically as a cream to treat actinic keratosis, a skin condition caused by sun damage. It is well-established in medical literature as an effective treatment for this condition. The main therapeutic indication is to reduce the number of precancerous skin lesions. At the molecular level, 5-Fluorouracil works by interfering with the DNA synthesis of rapidly dividing cells, which helps to eliminate abnormal skin cells. It is classified as an antimetabolite, a type of chemotherapy agent.

  • Calcipotriol

    This medication is also applied topically, often in combination with other treatments, to manage skin conditions like actinic keratosis. It is recognized in medical literature for its role in enhancing the effectiveness of other treatments. The primary therapeutic use is to help reduce skin lesions by modulating the immune response in the skin. Calcipotriol works by binding to vitamin D receptors, which helps regulate skin cell growth and differentiation. It is classified as a vitamin D analog.

Investigated diseases

Actinic Keratosis – Actinic Keratosis is a skin condition characterized by rough, scaly patches on areas of the skin that have been exposed to the sun over a long period. It is caused by damage from ultraviolet (UV) rays, typically from the sun or tanning beds. These patches can vary in color, appearing as red, pink, or brown, and are often found on the face, ears, lips, back of the hands, forearms, scalp, or neck. The condition progresses slowly and can sometimes develop into a more serious form of skin cancer if left untreated. Actinic Keratosis is more common in fair-skinned individuals and those who spend a lot of time outdoors. Regular monitoring and protection from sun exposure are important to manage the condition.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-511409-42-00Estimated enrolment232 patientsSponsorAcademisch Ziekenhuis Maastricht

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).