A Phase 3 interventional study of Vitamin D and Placebo in Asthma, Asthma Exacerbations and Preschool Child, sponsored by Professor Francine Ducharme. Completed at 9 sites in Canada. Open to participants aged 1 Year to 5 Years. Per ClinicalTrials.gov, last updated 2025-06-03.
Sponsored by Professor Francine Ducharme · Phase 3, Interventional, and Prevention
In this 7-month randomized controlled trial, children aged 1 to less than 6 years, with recurrent asthma attacks triggered mostly by colds, will receive a high dose of vitamin D or a placebo every 3.5 months during their usual clinic visit, and a daily supplement of vitamin D or a placebo. This study will test whether children in vitamin D group have less frequent and less severe asthma exacerbations compared with those receiving placebo.The study will also document the safety profile of this strategy.
This is a multicenter triple-blind randomized parallel-group, placebo-controlled trial of vitamin D3 supplementation. Children aged 1-5 (\<6) years with physician-diagnosed asthma predominantly triggered by upper respiratory tract infections will be screened for enrolment in paediatric asthma, respiratory or allergy clinics and the ED departments and randomized between Sept 1 to January 31, annually (4 recruitment years) and year around from 2022 onwards.
Using a computer-generated random list, stratified by site, children will be allocated (1:1) using permuted block randomisation method to enhance concealment.
Children will be followed for 7 months, with 3 visits every 3.5 months with repeated urine (for calcium:creatinine ratio) and blood samples. In addition, ten (10) days after each bolus, urine will be sampled for urinary calcium:creatinine ratio. In case of elevated urine calcium:creatinine ratio, a blood sample may be needed primarily for markers of calcium metabolism and exploratory outcomes. Only patients enrolled at CHU Sainte-Justine and Montreal Children's Hospital will receive a systematic home visit 10 days after first bolus for both urine and blood samples. There will be 6 follow-up phone calls, at week 1 and then monthly, to inquire about exacerbations and URTIs, remind parents to complete questionnaires and to collect a nasal swab at each exacerbation and screen for adverse events.
The main outcome is the number of courses of rescue oral corticosteroids (OCS) per child during the study period. Several secondary outcomes will be documented using biological samples and validated questionnaires to ascertain laboratory-confirmed respiratory infections, intensity and severity of exacerbations, mean number of ED visits, parents' functional status during exacerbations, de-intensification of preventive asthma therapy, cost effectiveness, and safety profile.
A sample of 432 children (400+7,5% attrition) per arm will provide 80% power with a two-tailed alpha of 5% to detect a 25% relative reduction in the mean number of exacerbations requiring OCS per child.
An intention-to-treat (ITT) analysis will be carried out with all randomised children.
4,841 studies on the registry are indexed under Asthma; 600 are open to participants now.
This study's enrollment of 323 is above the median of 78 across 3,341 interventional studies indexed under Asthma.
Browse Asthma studies →This is the only study on the registry with Professor Francine Ducharme as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Vitamin D supplement (100,000 IU) orally at baseline and at 3.5 months with daily 400 IU vitamin D for 7 months
Dietary Supplement: Vitamin D
Placebo orally at baseline and at 3.5 months with daily placebo during 7 months
Dietary Supplement: Placebo
2 mL of 50,000 IU/mL at baseline and at 3.5 months with a daily dose of 1 mL (400 IU/mL) for 7 months
Also known as: Cholecalciferol
2 mL of placebo at baseline and at 3.5 months with a daily dose of placebo (1 mL) for 7 months
Number of asthma exacerbations per child treated with rescue oral corticosteroids
Group difference in the mean number of exacerbations treated with rescue oral corticosteroids/child
Time frame: 7 months
Laboratory-confirmed respiratory infections
Group difference in (i) mean number of laboratory-confirmed respiratory infections per child and (ii) distribution of viruses during colds and/or asthma exacerbations
Time frame: 7 months
Mean number of ED visits and hospital admissions for asthma exacerbations
Group difference in mean number of ED visits and hospital admissions for asthma exacerbations per child
Time frame: 7 months
De-intensification of preventive asthma therapy
Group difference in proportion of children with de-intensification of preventive asthma therapy
Time frame: 3.5 and 7 months
Duration of asthma symptoms during asthma exacerbations
Group difference in the mean duration of symptoms during asthma exacerbations per child (i) documented in writing on the validated 'Asthma Flare-up Diary for Young Children' and (ii) reported verbally by parents,
Time frame: 7 months
Duration of B2-agonist use during asthma exacerbations
Group difference in the mean duration of B2-agonist use during asthma exacerbations per child (i) documented in writing on the validated 'Asthma Flare-up Diary for Young Children' and (ii) reported verbally by parents,
Time frame: 7 months
Severity of asthma symptoms during asthma exacerbations
Group difference in the severity of symptoms during asthma exacerbations per child documented on the 'Asthma Flare-up Diary for Young Children'
Time frame: 7 months
Intensity of use of rescue β2-agonists during asthma exacerbations
Group difference in the mean cumulative use of rescue β2-agonists per child during exacerbations documented on the validated 'Asthma Flare-up Diary for Young Children'
Time frame: 7 months
Parents' functional status during asthma exacerbations
Group difference in the mean parents' functional status during asthma exacerbations per child as documented on the validated 'Effect of a child's asthma flare-up on parents questionnaire'
Time frame: 7 months
Number of parental workdays lost
Group difference in the cumulative number of days of work or regular planned activities missed by parents to care for their child during asthma exacerbations
Time frame: 7 months
Parental productivity
Group difference in the extent to which parents were able to perform their work or regular planned activities during their child's acute asthma exacerbation (%)
Time frame: 7 months
Intervention cost-effectiveness
Cost of intervention vs. cost (family expenses and health care) of exacerbations
Time frame: 7 months
Hypercalcemia
Group difference in the proportion of children with clinically significant hypercalcemia (\>2.63 mmol/L)
Time frame: 7 months
Hypercalciuria
Group difference in the proportion of children with ≥1 occurrence of hypercalciuria (urinary calcium: creatinine ratio \>1.38 mmol/mmol for children aged 1-\<2 years, or \>1.1 mmol/mmol for children aged 2-\<5 years, or \>0.77 mmol/mmol for children aged ≥5 years)
Time frame: 7 months
Elevated serum 25-hydroxyvitamin D
Group difference in the proportion of children with ≥1 occurrence of elevated serum 25OHD (greater than 250 nmol/L)
Time frame: 7 months
Adverse Health Events
Group difference in the number and distribution of adverse health events
Time frame: 7 months
Serious Adverse Health Events
Group difference in the number of serious adverse health events
Time frame: 7 months
Gene expression
Group difference in the change in gene expression levels (between baseline and 3.5 months) in peripheral blood mononuclear cells (PBMC) in a subset of patients
Time frame: 3.5 months
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — There is a plan to make IPD and related data dictionaries available
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
Time frame: approximatively 18 months from datalock (Dec 2026)
Access criteria: to be determined
Ran from Oct 2018 to primary completion in Dec 2024, 74 months.
Of 32 non-industry phase 3 interventional studies under Asthma, half reached primary completion within 35 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 54. This study's 74 months is above that.
Counting every sponsor, half of 205 studies reached it within 27 months; a quarter within 14 and three quarters within 42.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Vitamin D