Skip to content
Clinical Trials – home
Not recruiting

Study of Topical Donepezil Hydrochloride Cream for Safety and Effectiveness in Adult Patients with Acne Vulgaris

Verified siteInvestigationalNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

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

This study is looking at acne vulgaris, which is a common skin condition that causes pimples and blemishes on the face. The treatment being tested is called AT-004, which is a cream that contains donepezil hydrochloride as its active ingredient. Some people in the study will receive the actual AT-004 cream while others will receive a placebo cream that looks the same but does not contain the active medicine. The purpose of this study is to find out if AT-004 cream is safe to use on the skin and if it works to improve acne.

During the study, participants will apply the cream to their face for a period of 12 weeks. The study doctors will check the skin for any side effects and will count the number of pimples to see if the treatment is working. These checks will happen at the beginning of the study and then again after 4 weeks, 8 weeks, and 12 weeks. The doctors will also take pictures of the acne at these visits to track any changes. Blood tests and other safety checks will be done to make sure the treatment is not causing any problems in the body.

The study will also look at how the treatment affects the quality of life of people with acne by using a questionnaire. In a small group of participants, the doctors will measure how much of the medicine gets into the bloodstream when applied to the skin. The study will compare results between people who use the AT-004 cream and those who use the placebo cream to determine if the treatment makes a difference in clearing acne and reducing both red, swollen pimples and blackheads or whiteheads.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial baseline visit and treatment start

    At the first visit, your acne severity will be assessed using a scoring system called Investigator Global Assessment, which rates acne from mild to severe on your face.

    The number of inflammatory lesions (red, swollen pimples) and noninflammatory lesions (blackheads and whiteheads) on your face will be counted.

    Your vital signs (such as blood pressure and heart rate), body weight, and overall physical health will be checked.

    Blood samples will be taken for laboratory safety tests.

    Photographs of your acne will be taken for comparison purposes.

    You will complete a questionnaire called the Dermatology Life Quality Index, which measures how acne affects your daily life.

    You will receive either AT-004 1% cream containing donepezil hydrochloride or a placebo cream that looks identical but contains no active ingredient. The assignment will be random, and neither you nor the study staff will know which one you receive.

    You will be instructed to apply the cream to the affected areas of your face as directed.

    The application site on your skin will be examined for any reactions.

  2. Step 2

    Week 4 assessment

    You will return for an assessment at 4 weeks after starting treatment.

    Your acne severity will be evaluated using the Investigator Global Assessment scoring system.

    The number of inflammatory lesions and noninflammatory lesions on your face will be counted and compared to the baseline.

    Photographs of your acne will be taken.

    You will complete the Dermatology Life Quality Index questionnaire again.

    The application site will be checked for any skin reactions.

    Any side effects or health changes will be recorded.

    Your vital signs and body weight will be measured.

    You will continue applying the cream as instructed.

  3. Step 3

    Week 8 assessment

    You will return for an assessment at 8 weeks after starting treatment.

    Your acne severity will be evaluated using the Investigator Global Assessment scoring system.

    The number of inflammatory lesions and noninflammatory lesions on your face will be counted and compared to previous visits.

    Photographs of your acne will be taken.

    You will complete the Dermatology Life Quality Index questionnaire again.

    The application site will be checked for any skin reactions.

    Any side effects or health changes will be recorded.

    Your vital signs, body weight, and physical health will be checked.

    Blood samples may be taken for laboratory safety tests.

    For a small group of 5 participants, additional blood samples will be collected to measure the amount of the study medication in the bloodstream.

    You will continue applying the cream as instructed.

  4. Step 4

    Week 12 final assessment

    You will return for a final assessment at 12 weeks after starting treatment.

    Your acne severity will be evaluated using the Investigator Global Assessment scoring system.

    The number of inflammatory lesions and noninflammatory lesions on your face will be counted and compared to all previous visits.

    Photographs of your acne will be taken.

    You will complete the Dermatology Life Quality Index questionnaire for the final time.

    The application site will be checked for any skin reactions.

    Any side effects or health changes will be recorded.

    Your vital signs, body weight, and physical health will be checked.

    Blood samples may be taken for final laboratory safety tests.

    This visit marks the end of the treatment period.

  5. Step 5

    Post-treatment period

    After completing the treatment at week 12, you will need to continue using effective contraception for an additional 3 months if you are a woman of childbearing potential.

    If you are a sexually active man with a female partner of childbearing potential, you must continue using condoms for an additional 3 months after the study ends.

Who can join the trial?

10 criteria

  • You must be between 18 years and 45 years old
  • You must have mild, moderate or severe facial acne, which means your doctor rates your acne as a score of 2 or higher on a special scale called Investigator Global Assessment or IGA, which is a way doctors measure how serious acne is
  • You must have at least 10 inflammatory lesions, which are red, swollen pimples, and at least 15 non-inflammatory lesions, which are blackheads or whiteheads, on your face
  • You must be in good enough health to safely take part in the study
  • You must provide informed consent, which means you agree in writing to participate after understanding what the study involves
  • If you are a woman who can become pregnant, you must use an effective birth control method from when you join the study until at least 3 months after the study ends
  • If you are a man who is sexually active with a woman who can become pregnant, you must agree to use a condom from when you join the study until at least 3 months after the study ends
  • If you are a male participant, you must agree to either be clean-shaven or have a neatly trimmed beard that does not get in the way of study checks from the beginning until the end of treatment
  • You must be willing and able to attend all required study visits and follow all study procedures
  • You must agree to have photographs taken of your acne at the beginning of the study and at follow-up visits at 4 weeks, 8 weeks, and 12 weeks

Who cannot join the trial?

7 criteria

  • The specific exclusion criteria (reasons why patients cannot participate) have not been provided in the available study information
  • Generally, clinical trials for acne vulgaris (a common skin condition with pimples and blemishes) may exclude patients who are pregnant or breastfeeding
  • Patients using certain medications that could affect the skin or interact with the study treatment may not be able to participate
  • People with other serious skin conditions or infections in the treatment area might be excluded
  • Individuals who are allergic (have a bad reaction) to ingredients in the study medication typically cannot join
  • Patients who have used other acne treatments very recently may need to wait before participating
  • People with certain medical conditions that could make the study unsafe for them may not be eligible
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

  • Verified

    Sanos A/S

    DenmarkGandrup, Denmark

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

  • AT-004

    is an experimental topical medication being tested as a cream or gel that you apply directly to your skin. In this study, it is being evaluated to see if it can help treat acne vulgaris, which is the common type of acne that causes pimples, blackheads, and whiteheads on the face and other areas. The medication is applied to the affected skin areas to see if it can reduce both the inflamed, red pimples and the non-inflamed blackheads and whiteheads that are characteristic of acne.

  • Placebo

    is an inactive treatment that looks like the real medication but contains no active medicine. It is used in this study to compare against the actual medication to help researchers determine if AT-004 truly works for treating acne. Some participants will receive the placebo instead of the active medication, but neither the participants nor the doctors will know who is receiving which treatment during the study.

What is already known about the treatment

AT-004 1% – AT-004 1% is an experimental topical medication being studied in phase 2 clinical trials for the treatment of acne vulgaris, which is the common form of acne that causes pimples and skin blemishes. This medication is applied directly to the skin and is currently under investigation to determine its safety, tolerability, and effectiveness in reducing both inflammatory lesions (red, swollen pimples) and non-inflammatory lesions (blackheads and whiteheads) in adults with acne. The study aims to assess how well the medication works after 8 weeks of treatment by measuring improvements in overall skin condition and counting the reduction in different types of acne lesions. The specific mechanism of action and pharmacological classification of AT-004 have not been publicly disclosed at this stage of clinical development.

Investigated diseases

Acne vulgaris – Acne vulgaris is a common skin condition that occurs when hair follicles become clogged with oil and dead skin cells. This blockage creates an environment where bacteria can multiply, leading to inflammation. The condition typically appears on the face, forehead, chest, upper back, and shoulders where oil glands are most concentrated. Acne vulgaris manifests as different types of lesions, including inflammatory lesions such as red, swollen pimples and non-inflammatory lesions such as blackheads and whiteheads. The condition often begins during adolescence due to hormonal changes but can affect people of all ages. The severity can range from mild with occasional breakouts to more severe forms with numerous inflamed lesions that may affect quality of life.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-521510-25-00Protocol codeAT-004_2024Estimated enrolment60 patientsSponsorArctic Therapeutics ehf.

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

Legal notice · Published by CTIN POLAND sp. z o.o., ul. rtm. Witolda Pileckiego 67/109, 02-781 Warsaw, Poland · KRS 0001111334 · REGON 528919042 · NIP 9512598637

© 2026 Clinical Trials EU – European Clinical Trials Information Network

GDPR compliance, ISO 9001 and ISO 27001 certified (LL-C Certification)

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).