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Study on the Effect of Fluconazole on the Intestinal Microbiome in Healthy Volunteers

Verified siteRegistered drugNo placebo
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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 understanding how an antifungal medication called fluconazole affects the community of microorganisms living in the intestines, known as the intestinal microbiome. The study involves healthy male volunteers between the ages of 18 and 35. The main goal is to see how taking fluconazole might change the balance and diversity of bacteria and fungi in the gut.

Participants in the study will be randomly assigned to receive either the antifungal medication fluconazole or no treatment at all. The study will last for a total of 14 days, during which the effects of the medication on the gut microbiome will be closely monitored. Researchers will look at changes in the types and amounts of bacteria and fungi present in the intestines immediately after the treatment period.

In addition to the initial 14-day period, the study will also examine the longer-term effects of fluconazole on the gut microbiome at 4 weeks and 6 months after treatment. This includes looking at how the gut microorganisms function and how the body's immune system responds. The study aims to provide insights into how antifungal treatments might impact the balance of microorganisms in the gut and overall health.

The research process

The trial runs in 6 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, you will be required to sign an informed consent form. This form confirms that you understand the study's purpose and agree to participate.

    You must be a male aged between 18 and 35 years, healthy as determined by a physician, and have a normal defecation pattern.

  2. Step 2

    Initial assessment

    A medical evaluation will be conducted, including a review of your medical history and a physical examination. This ensures that you meet the study's health criteria.

  3. Step 3

    Medication administration

    You will be given a medication called Fluconazole, which is an antifungal drug. It will be administered in the form of a hard capsule.

    The dosage is 200 mg, taken orally. You will take this medication once daily for a period of 14 days.

  4. Step 4

    Monitoring and data collection

    During the study, your gut microbiome will be monitored. This involves analyzing the bacteria and fungi in your intestines.

    Samples will be collected at the end of the 14-day medication period, and again at 4 weeks and 6 months after completing the medication.

  5. Step 5

    Immune response assessment

    Your body's immune response will be evaluated. This includes tests on blood cells and measuring antifungal antibodies.

    These assessments will occur at various points during the study to observe any changes over time.

  6. Step 6

    Completion of study

    The study is expected to conclude by January 31, 2024. At this point, all data collection and assessments will be completed.

Who can join the trial?

5 criteria

  • Must be male.
  • Must be between 18 and 35 years old at the time of signing the consent form.
  • Must be healthy, as determined by a doctor after a medical check-up, which includes reviewing medical history and a physical exam. If there is a minor health issue, the doctor must agree that it won't cause extra risks or interfere with the study.
  • Must be able to give written informed consent, which means you understand the study and agree to participate, and must be able to follow the study's rules and requirements.
  • Must have a normal bowel movement pattern, which means going to the bathroom no more than 3 times a day and at least 3 times a week.

Who cannot join the trial?

4 criteria

  • Participants must be healthy volunteers. This means you should not have any ongoing medical conditions.
  • Only male participants are allowed in this study.
  • Participants must be within a specific age range. Please ensure you meet the age requirements.
  • Participants should not be part of any vulnerable population. This means you should not be in a group that needs special protection, like children or people with certain disabilities.
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Verified sites

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  • Amsterdam UMC

    Verified

    The NetherlandsAmsterdam, The Netherlands

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Investigated drugs

Fluconazole is a medication used to treat fungal infections. In this clinical trial, it is being studied to see how it affects the bacteria and other microorganisms living in the intestines. The goal is to understand if taking fluconazole changes the balance of these microorganisms, which are important for digestion and overall health.

What is already known about the treatment

Fluconazole – Fluconazole is an antifungal medication typically administered orally in the form of tablets or liquid, and it can also be given intravenously. It is currently being studied for its effects on the intestinal microbiome in healthy volunteers, as part of a proof-of-concept clinical trial. The main therapeutic use of fluconazole is to treat and prevent fungal infections, particularly those caused by Candida species. At the molecular level, fluconazole works by inhibiting an enzyme necessary for the production of ergosterol, a key component of fungal cell membranes, thereby disrupting the growth and replication of the fungus. It is classified pharmacologically as an azole antifungal agent.

Investigated diseases

Not applicable - Healthy Volunteer study – This study involves individuals who do not have any specific medical conditions or diseases. The focus is on understanding the effects of a treatment or intervention in a population that is generally healthy. Participants are typically selected to provide baseline data or to observe the effects of a treatment without the influence of existing health issues. The progression in this context refers to the changes observed in the participants' health or biological markers over time as a result of the study intervention. In this case, the study aims to investigate the impact of an antifungal drug on the intestinal microbiota. The progression is monitored through changes in gut bacteriome and mycobiome composition, as well as immune response profiles.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-503710-69-00Estimated enrolment50 patientsSponsorAmsterdam UMC Stichting

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