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Study on Vitamin D for Patients with Depression or Bipolar Disorder

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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 in individuals diagnosed with either depressive disorder or bipolar disorder. The treatment being tested is a form of vitamin D known as cholecalciferol, which is administered as an oral solution called DIBASE 50,000 U.I./2.5 ml. The study aims to evaluate how this vitamin D treatment affects patients with these mental health conditions over a period of 12 weeks.

Participants in the study will receive either the vitamin D supplement or a placebo. The trial will monitor changes in the severity of depression symptoms using a tool called the Montgomery-Asberg Depression Rating Scale (MADRS). The study will also track the time it takes for symptoms to improve significantly. Additionally, the study will measure changes in vitamin D levels in the body at both 12 and 24 weeks.

The goal of this research is to understand whether vitamin D supplementation can be an effective treatment option for people with depressive or bipolar disorders. By participating in this study, researchers hope to gather valuable information that could lead to better treatment strategies for these conditions in the future.

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 assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes verifying age (18-75 years), diagnosis of major depressive disorder or bipolar disorder, and a Montgomery-Asberg Depression Rating Scale (MADRS) score greater than 15.

    Blood tests are performed to check serum levels of 25(OH) Vitamin D, which must be less than 20 ng/ml.

    Confirmation of stable antipsychotic therapy for at least two weeks is required.

    Ability to take Vitamin D supplementation in oral form is assessed.

  2. Step 2

    Treatment initiation

    Participants begin treatment with cholecalciferol (Vitamin D) in the form of an oral solution called DIBASE 50,000 U.I./2.5 ml.

    The oral solution is administered once every two weeks for a total duration of 12 weeks.

  3. Step 3

    Midpoint evaluation

    At 12 weeks, an evaluation is conducted to measure changes in the MADRS score.

    Blood tests are repeated to assess changes in 25(OH) Vitamin D levels.

  4. Step 4

    Extended observation

    Participants continue to be monitored for an additional 12 weeks, totaling 24 weeks of observation.

    Further assessments of the MADRS score and 25(OH) Vitamin D levels are conducted at the end of this period.

  5. Step 5

    Final assessment

    At the end of 24 weeks, a final assessment is performed to evaluate the overall effectiveness of the Vitamin D supplementation.

    The primary focus is on the change in the MADRS score and the time to remission of depressive symptoms.

Who can join the trial?

7 criteria

  • Age between 18 and 75 years.
  • Referred to the Psychiatry Unit with a diagnosis of major depressive disorder or bipolar disorder. These are mental health conditions that affect mood and behavior.
  • MADRS score greater than 15. This is a scale used to measure the severity of depression symptoms.
  • Blood level of 25(OH) Vitamin D less than 20 ng/ml. This is a measure of Vitamin D in the blood, which is important for bone health and other body functions.
  • On a stable antipsychotic therapy for at least two weeks. This means taking medication regularly to help manage symptoms of mental health conditions.
  • Able to take Vitamin D supplements in pill form.
  • Willing to give free and informed consent, meaning you agree to participate after understanding the study details.

Who cannot join the trial?

4 criteria

  • Individuals who are not diagnosed with either depressive disorder or bipolar disorder cannot participate. These are mental health conditions that affect mood and behavior.
  • Participants must be within a specific age range, typically adults, to be eligible.
  • Both males and females are eligible, so gender is not a reason for exclusion.
  • Individuals who are considered part of a vulnerable population, such as those unable to give informed consent, are not included.
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Investigated drugs

Vitamin D (Cholecalciferol) is being studied for its potential benefits in patients with depressive disorder or bipolar disorder. The trial aims to evaluate how this supplement might help improve symptoms of these conditions over a period of 12 weeks. Vitamin D is often known for its role in bone health, but it is also being explored for its effects on mood and mental health.

What is already known about the treatment

Cholecalciferol – Cholecalciferol, commonly known as Vitamin D3, is administered orally, typically in the form of tablets or capsules. It is currently being studied in clinical trials for its potential benefits in treating depressive disorder and bipolar disorder. The main therapeutic indication is to assess its effectiveness in improving mood and mental health in these conditions. At the molecular level, cholecalciferol works by influencing the expression of genes involved in mood regulation and brain function, potentially through its role in calcium homeostasis and neuroprotection. It is classified as a vitamin supplement, specifically a form of Vitamin D.

Investigated diseases

  • Depressive Disorder

    This is a mental health condition characterized by persistent feelings of sadness, hopelessness, and a lack of interest or pleasure in activities. It can affect how a person thinks, feels, and handles daily activities. Symptoms may include changes in appetite, sleep disturbances, fatigue, and difficulty concentrating. The severity and duration of symptoms can vary, and they may interfere with a person's ability to function at work or in social situations. Over time, these symptoms can lead to significant emotional and physical problems.

  • Bipolar Disorder

    This is a mental health condition marked by extreme mood swings that include emotional highs (mania or hypomania) and lows (depression). During manic phases, individuals may feel overly happy, energetic, or irritable, and may engage in impulsive behaviors. Depressive phases can involve feelings of sadness, hopelessness, and a loss of interest in most activities. These mood swings can affect sleep, energy, activity, judgment, behavior, and the ability to think clearly. The frequency and intensity of these episodes can vary widely among individuals.

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase ITrial ID2025-520778-20-00Protocol codeVIT_D_2018Estimated enrolment150 patientsSponsorAzienda Ospedaliera Universitaria Senese

sourced from the EU Clinical Trials Register and site verification

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