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Study Comparing Mepacrine and Metronidazole for Treating Resistant Giardiasis in Children Aged 1 to 18 Years

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 studying intestinal giardiasis, a condition caused by a parasite that affects the digestive system, particularly in children. The trial will compare two treatments: quinacrine and metronidazole. Quinacrine is being tested in the form of capsules and tablets, while metronidazole is provided as tablets. The purpose of the study is to evaluate the safety and effectiveness of quinacrine in treating children with giardiasis that has not responded to standard treatments.

Participants in the study will receive either quinacrine or metronidazole. Quinacrine will be given at a dose of 6 mg per kilogram of body weight, three times a day, for five days. The study aims to see if quinacrine is as effective as metronidazole, which is the usual treatment for this condition. The trial will also monitor for any side effects and how well the children tolerate the medications.

The study will last for several years, with the goal of gathering enough information to determine the best treatment option for children with resistant giardiasis. Researchers will collect data on how well the treatments work in eliminating the parasite and any potential side effects experienced by the participants. This information will help in developing better treatment strategies for children affected by this condition.

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, eligibility is confirmed. Participants are children aged 1 to 18 years diagnosed with intestinal giardiasis and have not responded to initial treatment.

  2. Step 2

    Randomization

    Participants are randomly assigned to one of two groups. One group receives quinacrine, and the other receives metronidazole.

  3. Step 3

    Quinacrine administration

    Participants in the quinacrine group take quinacrine at a dose of 6 mg per kilogram of body weight per day. The medication is taken orally every 8 hours for 5 days.

  4. Step 4

    Metronidazole administration

    Participants in the metronidazole group take metronidazole in high doses. The medication is taken orally, following the prescribed schedule.

  5. Step 5

    Monitoring and data collection

    Throughout the trial, participants are monitored for the presence of Giardia intestinalis to assess the effectiveness of the treatment.

    Blood and hair samples may be collected to measure drug levels at different times.

    Participants are observed for any side effects or adverse reactions to the medications.

  6. Step 6

    Completion of the trial

    The trial is expected to conclude by April 1, 2028. The primary goal is to determine the proportion of participants who achieve eradication of the parasite.

    Secondary outcomes include understanding drug concentrations and any genetic factors related to resistance.

Who can join the trial?

4 criteria

  • Children aged 1 to 18 years old.
  • Diagnosed with **intestinal giardiasis**. This means they have a specific type of infection in the intestines caused by a parasite called Giardia.
  • Must have **informed consent/assent**. This means that the child and their parents or guardians understand the study and agree to participate.
  • Must be **refractory to first line treatment**. This means that the usual treatment for the infection did not work for them.

Who cannot join the trial?

6 criteria

  • Children younger than 1 year old or older than 18 years cannot participate.
  • Participants must not have any other serious health conditions that could interfere with the study.
  • Individuals who are pregnant or breastfeeding are not eligible.
  • Participants should not have allergies to the study medication or similar drugs.
  • Those who have taken part in another clinical trial recently may be excluded.
  • Participants must not have any condition that makes it unsafe for them to take the study medication.
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Investigated drugs

  • Quinacrine

    is a medication being tested in this trial for its ability to treat giardiasis, an intestinal infection caused by a parasite. The trial aims to see if quinacrine is safe and works as well as the standard treatment for children who have giardiasis that is resistant to other treatments.

  • Metronidazole

    is the standard medication used to treat giardiasis. In this trial, it is used as a comparison to see if quinacrine can be as effective in treating children with resistant giardiasis.

What is already known about the treatment

  • Quinacrine

    Quinacrine is administered orally in tablet form, typically given every 8 hours for a period of 5 days. It is currently being studied in clinical trials for its effectiveness against resistant intestinal giardiasis, particularly in children. The medication works by interfering with the DNA and RNA synthesis of the parasite, ultimately leading to its death. Quinacrine is classified as an antiprotozoal agent and has been used historically for various parasitic infections.

  • Metronidazole

    Metronidazole is also administered orally, often in tablet form, and is a standard treatment for giardiasis. It is well-established in medical literature as an effective treatment for various infections caused by anaerobic bacteria and certain parasites. The drug works by entering the cells of the microorganism and disrupting its DNA, leading to cell death. Metronidazole is classified as an antibiotic and antiprotozoal medication.

Investigated diseases

Intestinal giardiasis – Intestinal giardiasis is an infection of the small intestine caused by the parasite Giardia intestinalis. It is commonly transmitted through contaminated water or food. The disease often leads to symptoms such as diarrhea, abdominal cramps, bloating, and nausea. In some cases, individuals may experience fatigue and weight loss due to malabsorption of nutrients. The infection can be acute or chronic, with symptoms lasting from a few days to several weeks. It is particularly prevalent in areas with poor sanitation and can affect individuals of all ages, though children are more susceptible.
Trial detailsLast updated 7 Oct 2026
Age0-17PhasePhase ITrial ID2023-510227-30-00Protocol codeQUIN4KIDSEstimated enrolment48 patientsSponsorFundacion Para La Investigacion Biomedica Del Hospital Universitario La Paz

sourced from the EU Clinical Trials Register and site verification

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