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Study on Vitamin D Deficiency Treatment in Obese Children and Adolescents Using Colecalciferol: Comparing Monthly Boluses and Daily Doses

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What is this trial about?

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

This clinical trial focuses on treating a condition known as vitamin D deficiency in obese children and adolescents. The study will use two forms of a medication called colecalciferol, which is also known as vitamin D3. The two treatments being compared are ZYMAD 50,000 UI, an oral solution taken in ampoules, and ZYMAD 10,000 UI/ml, an oral solution taken in drops. The purpose of the study is to compare the effectiveness of these two vitamin D supplementation methods in increasing vitamin D levels in the blood.

Participants in the study will be randomly assigned to one of two groups. One group will receive a monthly dose of the medication, while the other group will take a daily dose. The study will last for three months, during which time the vitamin D levels in the participants' blood will be monitored. The study aims to determine which dosing method is more effective in correcting vitamin D levels in the participants.

Throughout the study, additional health markers such as calcium and phosphorus levels in the blood and urine will be checked. The study will also consider factors like skin type, physical activity, sun exposure, and dietary intake. For participants aged 10 and older, bone mineral density will be measured using a method called DXA, which stands for dual-energy X-ray absorptiometry. This will help assess any changes in bone health during the study period.

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

    The study involves children and adolescents aged 5 to 18 years who are classified as obese based on specific criteria.

    Participation requires agreement from the patient and written consent from both parents or legal guardians.

  2. Step 2

    Initial assessment

    An initial assessment is conducted to measure baseline levels of vitamin D, calcium, and phosphorus in the blood and urine.

    Additional assessments include determining skin type, physical activity, sun exposure, and dietary intake.

  3. Step 3

    Treatment allocation

    Participants are randomly assigned to one of two treatment groups: a monthly bolus group or a daily supplementation group.

    The monthly bolus group receives ZYMAD 50,000 UI oral solution once a month.

    The daily supplementation group receives ZYMAD 10,000 UI/ml oral drops daily.

  4. Step 4

    Treatment period

    The treatment period lasts for three months.

    Participants in the daily group maintain a diary to record their intake, while those in the bolus group report the number of ampoules taken.

  5. Step 5

    Follow-up assessment

    After three months, a follow-up assessment is conducted to measure changes in vitamin D, calcium, and phosphorus levels.

    Bone mineral density is evaluated for participants aged 10 years and older.

  6. Step 6

    Data analysis

    The effectiveness of the two treatment regimens is compared based on the changes in vitamin D levels and other health indicators.

Who can join the trial?

4 criteria

  • The child or adolescent must be between the ages of 5 and 17 years old.
  • The child or adolescent must be **obese**, which means having a **Body Mass Index (BMI)** greater than the 97th percentile for their age and gender. This is a way to measure if someone is much heavier than is healthy for their height.
  • The child or adolescent must agree to participate, and both parents or legal guardians must provide written permission.
  • The child or adolescent must be part of the national health system or have access to its benefits.

Who cannot join the trial?

4 criteria

  • Children and adolescents who are not considered obese cannot participate. Obese means having a body weight that is much higher than what is considered healthy for their age and height.
  • Participants must be within a certain age range, specifically children and adolescents. If someone is too young or too old, they cannot join the study.
  • Both boys and girls can participate, but if someone does not identify as either, they may not be eligible.
  • Participants should not belong to a group considered vulnerable. Vulnerable means being in a situation where they might not be able to make fully informed decisions about joining the study.
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Investigated drugs

Vitamin D is being studied in this trial to see how well it works in increasing vitamin D levels in the blood of obese children and adolescents. The trial is comparing two different ways of giving vitamin D: one group receives a large dose once a month, while the other group takes a smaller dose every day. The goal is to find out which method is more effective in correcting vitamin D deficiency.

What is already known about the treatment

Vitamin D – This medication is administered orally and can be given as either a daily dose or a monthly bolus. It is currently being studied in clinical trials to determine the most effective regimen for increasing vitamin D levels in obese children and adolescents. The main therapeutic indication is to treat vitamin D deficiency in this population. At the molecular level, vitamin D works by promoting calcium absorption in the gut and maintaining adequate serum calcium and phosphate concentrations, which are necessary for bone health. It is classified as a vitamin supplement.

Investigated diseases

Obesity in Children and Adolescents – Obesity in children and adolescents is a condition characterized by excessive body fat that negatively affects a child's health or well-being. It is typically caused by a combination of genetic, behavioral, and environmental factors. As children grow, their bodies require more energy, but when they consume more calories than they burn, the excess is stored as fat. Over time, this can lead to an increase in body weight and body mass index (BMI) beyond what is considered healthy for their age and height. This condition can lead to various health issues, including problems with bones and joints, sleep apnea, and social and psychological problems. It is important to address obesity early to prevent long-term health complications.
Trial detailsLast updated 7 Oct 2026
Age0-17PhasePhase IIITrial ID2023-507089-18-00Protocol code69HCL18_0148Estimated enrolment68 patientsSponsorHospices Civils De Lyon

sourced from the EU Clinical Trials Register and site verification

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