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Study on Vitamin D Supplementation (Colecalciferol) and Its Effect on Urinary Calcium Levels in Children and Teens Aged 2 to 18 Years

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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 effects of vitamin D supplementation on a condition known as hypercalciuria, which is characterized by high levels of calcium in the urine. The study involves children and adolescents aged 2 to 18 years. Two forms of vitamin D, known as colecalciferol or vitamin D3, will be used in the trial. These are available as oral solutions called ADRIGYL 10,000 UI/ml and UVEDOSE 100,000 UI. The purpose of the study is to evaluate how different ways of taking vitamin D, either as a high dose given at once or as a smaller daily dose, affect the occurrence of hypercalciuria.

Participants in the study will be randomly assigned to one of two groups. One group will receive a high dose of vitamin D at the start, while the other group will take a smaller dose daily. The study will last for 28 days, and urine samples will be collected on days 7, 14, and 28 to measure the levels of calcium. This will help determine if the way vitamin D is taken influences the development of hypercalciuria. Additionally, the study will monitor for any side effects or unexpected reactions to the vitamin D supplementation.

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, ensure that the informed consent form is signed by your parents or yourself if you are an adult. This confirms your understanding and agreement to participate in the study.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to confirm eligibility. This includes verifying your age, which should be between 2 and 18 years, and ensuring you are covered by a social security scheme.

  3. Step 3

    Medication administration

    You will be randomly assigned to one of two groups. One group will receive a high sequential dose of vitamin D using UVEDOSE 100,000 UI, an oral solution taken in a single dose. The other group will receive a daily dose of vitamin D using ADRIGYL 10,000 UI/ml, an oral drop solution taken daily. The specific dosage and frequency will be explained to you based on your group assignment.

  4. Step 4

    Urine sample collection

    You will need to provide a first morning urine sample on day 7, day 14, and day 28. This is to measure the calcium/creatinine ratio, which helps assess the occurrence of hypercalciuria, a condition where there is too much calcium in the urine.

  5. Step 5

    Monitoring and follow-up

    Throughout the study, you will be monitored for any expected or unexpected side effects. It is important to report any changes in your health to the study team immediately.

  6. Step 6

    Completion of the study

    After the final urine sample collection on day 28, your participation in the study will be complete. The study team will provide you with any necessary follow-up information or instructions.

Who can join the trial?

3 criteria

  • Children aged 2 to 18 years can participate.
  • Parents or guardians must provide informed consent, which means they agree to the child's participation after understanding the study details. If the participant is an adult, they must provide their own consent.
  • Participants must be covered by a social security scheme, which is a system that provides financial support for healthcare.

Who cannot join the trial?

1 criterion

  • Patients with **transient hypercalciuria** cannot participate. This means if you have a temporary condition where there is too much calcium in your urine, you cannot join the study.
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Investigated drugs

Vitamin D is a nutrient that helps your body absorb calcium, which is important for building and keeping strong bones. In this clinical trial, Vitamin D is being given to children and teenagers to see how different ways of taking it might affect the amount of calcium in their urine. The study is comparing two methods: taking a high dose all at once or taking smaller amounts every day. The goal is to find out which method is better for managing calcium levels in the body.

What is already known about the treatment

Vitamin D Supplementation – This medication is administered either as a high sequential dose or as a daily intake, typically in the form of oral tablets or liquid drops. It is currently being studied in clinical trials to understand its effects on hypercalciuria, a condition characterized by high levels of calcium in the urine, particularly in children and adolescents aged 2 to 18 years. The main therapeutic indication is to manage and prevent transient hypercalciuria. At the molecular level, Vitamin D helps regulate calcium and phosphate balance in the body, promoting healthy bone formation. It is classified as a vitamin supplement, essential for maintaining bone health and supporting the immune system.

Investigated diseases

Transient hypercalciuria – Transient hypercalciuria is a temporary condition characterized by an elevated level of calcium in the urine. This condition can occur when the body excretes more calcium than normal, which can be influenced by dietary factors, medications, or other temporary changes in the body. The excess calcium in the urine can lead to the formation of crystals, which may cause discomfort or other urinary symptoms. Over time, if the condition persists, it can potentially lead to the development of kidney stones. However, in transient cases, the condition often resolves on its own once the underlying cause is addressed. Monitoring and managing dietary intake of calcium and other related nutrients can help in managing the condition.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-518219-20-00Protocol code15_0500Estimated enrolment280 patientsSponsorCentre Hospitalier Universitaire De Montpellier

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