Vitamin D Supplementation in HIV-infected Youth

Study Overview
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Brief Summary
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Along with its effects on bone metabolism, vitamin D is an important modulator of the immune system. Experimental studies have shown that the active metabolite of vitamin D [1,25(OH)2D] is able to skew the T cell compartment into a more anti-inflammatory state, with inhibition of Th1 and Th17 cells and promotion of Th2 and T regulatory subsets. In the context of HIV infection, in which Th1 subpopulations are devoted to inhibit viral replication, any alteration of the Th1/Th2 balance would be of concern. The aim of this Randomized Controlled Trial is to test wether oral supplementation with cholecalciferol could be able: 1) to improve vitamin D status and, 2) to play an immunomodulatory role, in vertically HIV-infected children and young adults with hypovitaminosis D.

Detailed Description
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There is increasing evidence that hypovitaminosis D is common in the general population. Low dietary intake of vitamin D and reduced exposure to sunlight are probably the major risk factors. A high prevalence of hypovitaminosis D has been described in HIV-infected adults, and children. HIV infection itself and antiretroviral (ARV) treatment may be responsible for alteration of vitamin D metabolism. For instance, studies have shown a significant decrease in serum 25-hydroxyvitamin-D [25(OH)D] concentration in adults receiving non-nucleoside reverse transcriptase inhibitors (NNRTIs). Whatever the cause(s) of hypovitaminosis D, because of the importance of vitamin D in bone health, randomized controlled trials (RCT) have been performed to test whether vitamin D supplementation can improve vitamin D status and bone mineral metabolism in HIV-infected children and adolescents. Along with its effects on bone metabolism, vitamin D is an important modulator of the immune system. The vitamin D receptor (VDR) is found in high concentrations in activated T lymphocytes, in small amounts in monocyte/macrophage cells while B lymphocytes do not contain detectable amounts of VDR. Experimental studies have shown that the active di-hydroxylated metabolite of vitamin D [1,25(OH)2D] is able to skew the T cell compartment into a more anti-inflammatory state, with inhibition of Th1 and Th17 cells and promotion of Th2 and T regulatory (Treg) subsets. In the context of HIV infection, in which Th1 subpopulations are devoted to inhibit viral replication, 16 any alteration of the Th1/Th2 balance would be of concern. Although all the biological effects of vitamin D are mediated by the 1,25(OH)2D, it is the 25(OH)D to be routinely quantified because of its longer half-life.17 However, HIV-infected subjects may have a defective 1α-hydroxylation of 25(OH)D. Thus, it is important to evaluate the effects of vitamin D supplementation both in terms of 25(OH)D and 1,25(OH)2D responses. This repeated-measures parallel-group RCT is aimed to test wether a 12-month oral supplementation with cholecalciferol (vitamin D3) is able: 1) to increase serum 25(OH)D and 1,25(OH)2D levels and, 2) to affect T-cell phenotype in vertically HIV-infected children and young adults with hypovitaminosis D and stable HIV-disease. Main outcome: to determine the frequency of hypovitaminosis D at 12-month of follow-up among subjects supplemented with oral cholecalciferol versus subjects receiving placebo. Secondary outcome: to investigate correlations - if any - between serum vitamin D concentration and markers of immune activation (i.e. Th1-, Th2-, Th17- and Treg-lymphocytes count, T-lymphocyte VDR expression)

Official Title
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Vitamin D Status and T Cell Phenotype in HIV-infected Youth Supplemented With Cholecalciferol: a Randomized Clinical Trial.

Conditions
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HIV Disease, Vitamin D Deficiency, Hypovitaminosis D, Hyperparathyroidism

Intervention / Treatment
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* Drug: oral cholecalciferol 1000000 UI (vitamin D3)
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Vertically acquired HIV infection age < 30 years serum 25(OH)D concentration < 30 ng/mL signed written informed consent Exclusion Criteria: hyperparathyroidism, as detected by an intact serum parathyroid hormone (PTH) ≥ 65 pg/mL Black ethnic group any supplementation with vitamin D in the previous 12 months use of any treatment known to alter vitamin D status in the previous 6 months (excluding ARV) any concomitant severe illness.

Ages Eligible for Study
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Maximum Age: 30 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
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vitamin D<br>oral cholecalciferol 1000000 UI (vitamin D3). At 0, 3, 6 and 9 months, the vitamin D group received orally 100000 IU of cholecalciferol suspended in 2 mL of olive oil in sealed plastic syringes labeled with the unique identification numbers. | Drug: oral cholecalciferol 1000000 UI (vitamin D3)<br> <br> * Other names: DIBASE - ABIOGEN PHARMA Spa;|
| Placebo Comparator: placebo<br>placebo At 0, 3, 6 and 9 months, the placebo group received 2 mL of olive oil, in sealed plastic syringes labeled with the unique identification numbers. | Drug: Placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| frequency of Hypovitaminosis D [serum 25(OH)D < 30 ng/mL] in the Vitamin D receiving group vs placebo group | Vertically HIV-infected patients aged <30 years and with serum 25(OH)D < 30 ng/mL were randomized into the vitamin D or placebo group. At baseline (0 months), 3, 6 and 9 months, the intervention group received orally 100000 IU of cholecalciferol. Serum 25(OH)D, 1,25(OH)2D, PTH and CD4+ T cells were assessed 3 months before baseline, at 0, 3, 6, 9 and 12 months, while Th1-, Th2-, Th17- and Treg-subsets and T-lymphocyte vitamin D receptor at 0, 3 and 12 months | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of oral cholecalciferol supplementation on T cell phenotype in vertically HIV-infected youth with stable HIV diseases | Vertically HIV-infected patients aged <30 years and with serum 25(OH)D < 30 ng/mL were randomized into the vitamin D or placebo group. At baseline (0 months), 3, 6 and 9 months, the intervention group received orally 100000 IU of cholecalciferol. CD4+ T-cells were assessed 3 months before enrollment (-3 months), at baseline (0 months) and at each visit thereafter (3, 6, 9 and 12 months). T-lymphocyte VDR expression and Th1-, Th2-, Th17- and Treg-lymphocytes were measured at 0, 3 and 12 months. | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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HIV, children, adolescents, Vitamin D, immunity, T cell phenotype