Cholecalciferol Comedication in IBD - the 5C-study

Study Overview
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Brief Summary
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Vitamin D deficiency (defined as 25(OH)-vitamin D serum level <50 nmol/ l) is associated with irritable bowel disease (IBD). National guidelines recommend the administration of 800 -4000 IU cholecalciferol daily for an effective treatment, especially during the winter (poor sun exposition). Cumulative intermittent administration monthly or weekly is possible. The study aims to compare inflammation activity (primary outcome) after monthly or weekly treatment with soft capsules containing 24'000 IU cholecalciferol compared to no vitamin D supplementation. Quantification of 25(OH)-vitamin D serum values is a secondary outcome. The investigators will use newly developed soft capsules.

Detailed Description
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Monthly supplementation: Monthly administration of a capsule containing 24'000 IU vitamin D, corresponding to a dose of approximately 800 IU per day, as comedication to the usual treatment during 6 months. Weekly supplementation: Weekly administration of a capsule containing 24'000 IU vitamin D, corresponding a dose of approximately 3500 IU per day, as comedication to the usual treatment during 6 months. Control: Usual treatment without vitamin D supplementation. All 3 groups: In a follow-up phase of 6 months, all participants can choose whether they want a monthly vitamin D supplementation or not.

Official Title
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Cholecalciferol Comedication in Patients With Chronic Inflammatory Bowel Diseases (Crohn's Disease or Ulcerative Colitis) - the 5C-study

Conditions
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Inflammatory Bowel Diseases

Intervention / Treatment
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* Drug: Vitamin D3


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: diagnosis of Crohn disease or ulcerative colitis Exclusion Criteria: hypercalcaemia

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Parallel Assignment Patient will be recruited by their regularly visit. Patients will be randomly assigned to be supplemented with monthly capsules (monthly group), weekly capsules (weekly group) or no supplementation (control group).
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: weekly supplementation<br>Weekly administration of a capsule containing 24'000 IU vitamin D, corresponding to a dose of approximately 3500 IU per day, as comedication to the usual treatment during 6 months. | Drug: Vitamin D3<br>* 24,000 IU cholecalciferol<br>* Other names: D3 VitaCaps;|
| Active Comparator: monthly supplementation<br>Monthly administration of a capsule containing 24'000 IU vitamin D, corresponding to a dose of approximately 800 IU per day, as comedication to the usual treatment during 6 months. | Drug: Vitamin D3<br>* 24,000 IU cholecalciferol<br>* Other names: D3 VitaCaps;|
| No Intervention: control group<br>Usual treatment without vitamin D supplementation. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| fecal calprotectin | laboratory disease activity | every 2 months during 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| (OH)-vitamin D serum value | serum value cholecalciferol | every 2 months during 6 months |