Vitamin D2 vs Vitamin D2 Plus Calcitriol in Cholestatic Children With Vitamin D Deficiency (VITD-CHOL)

Accelerated Correction of Vitamin D Deficiency in Cholestatic Children: a Comparative Trial of Vitamin D2 Monotherapy vs Combination Therapy With Calcitriol

The goal of this clinical trial is to learn whether adding calcitriol to vitamin D2 can improve vitamin D deficiency in children with cholestasis and chronic liver disease. Cholestasis is a condition in which bile flow is reduced, which can make it difficult for the body to absorb and process vitamin D. The study will also learn about the safety of using vitamin D2 together with calcitriol.

The main questions it aims to answer are:

• Does vitamin D2 plus calcitriol increase blood 25-hydroxyvitamin D (25-OHD) levels more than vitamin D2 alone after 3 months of treatment?
• Does vitamin D2 plus calcitriol help more children reach an adequate vitamin D level by 3 and 6 months?
• What medical problems, especially high calcium or high phosphorus levels, occur during treatment?

Researchers will compare children who receive vitamin D2 alone with children who receive vitamin D2 plus calcitriol to see which treatment improves vitamin D levels more effectively and safely.

Participants will:

• Take vitamin D2 alone or vitamin D2 plus calcitriol as assigned by randomization
• Visit the clinic for study assessments at the start of the study, at 3 months, and at 6 months
• Have blood tests to measure vitamin D levels, calcium, phosphorus, parathyroid hormone, liver function, and other safety markers
• Have their treatment reviewed at 3 months; participants whose vitamin D level remains low may have their treatment adjusted according to the study plan
• Bring back medication packages so researchers can check how regularly the study medicines were taken

Study Overview

• Status: Recruiting
• Conditions: Vitamin D Deficiency; Children; Cholestatic Liver Disease; Chronic Liver Disease (CLD)
• Intervention / Treatment: Drug: Vitamin D2; Drug: Calcitriol

• Study Type: Interventional
• Enrollment (Estimated): 54
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: THANAPORN NiLYAEM; Phone Number: 66852811244; Email: namobnamob@docchula.com

Study Locations

• Thailand
  • Bangkok, Thailand, 10330
    • Recruiting
    • King Chulalongkorn Memorial Hospital
    • Contact: King Chulalongkorn Memorial Hospital; Phone Number: 6622564493; Email: research@chula.ac.th

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients younger than 18 years of age.
• Patients diagnosed with cholestasis, defined as direct/conjugated bilirubin >1 mg/dL for more than 1 month.
• Patients diagnosed with chronic liver disease.
• Patients with vitamin D deficiency, defined as serum 25-hydroxyvitamin D (25-OHD) level <20 ng/mL, according to the Endocrine Society Clinical Practice Guideline.

Exclusion Criteria:

• Pre-existing hypercalciuria, screened by urine calcium testing before enrollment.
• Patients with benign or malignant tumors.
• Patients with renal tubular defects, screened by electrolyte testing before enrollment.
• Patients currently receiving anticonvulsant therapy.
• Patients who do not attend scheduled follow-up visits.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Vitamin D2 Monotherapy; Participants in this arm will receive vitamin D2 40,000 IU orally once weekly for 3 months. At month 3, participants whose 25-hydroxyvitamin D level remains below 20 ng/mL may receive treatment adjustment according to the study protocol.	Drug: Vitamin D2; Vitamin D2 40,000 IU/week weekly
Experimental: Vitamin D2 Plus Calcitriol; Participants in this arm will receive vitamin D2 40,000 IU orally once weekly plus calcitriol 50 ng/kg/day orally for 3 months. At month 3, participants whose 25-hydroxyvitamin D level remains below 20 ng/mL may receive treatment adjustment according to the study protocol.	Drug: Vitamin D2; Vitamin D2 40,000 IU/week weekly; Drug: Calcitriol; Calcitriol 50 ng/kg/day once daily

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Baseline in Serum 25-Hydroxyvitamin D Concentration at Month 3	Change from baseline in serum 25-hydroxyvitamin D [25(OH)D] concentration, measured in ng/mL, at 3 months after treatment initiation. The change will be calculated as the Month 3 value minus the baseline value and compared between treatment groups.	Baseline and Month 3

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Serum 25-Hydroxyvitamin D Level From Baseline to Month 6	Change in serum 25-hydroxyvitamin D (25-OHD) level, measured in ng/mL, from baseline to 6 months after treatment initiation.	Baseline to Month 6
Number of Participants With Correction of Vitamin D Deficiency at Month 3	Number and percentage of participants with serum 25-hydroxyvitamin D [25(OH)D] concentration greater than or equal to 20 ng/mL at Month 3.	Month 3
Number of Participants With Correction of Vitamin D Deficiency at Month 6	Number and percentage of participants with serum 25-hydroxyvitamin D [25(OH)D] concentration greater than or equal to 20 ng/mL at Month 6.	Month 6
Change From Baseline in Serum Parathyroid Hormone Concentration at Month 3 and Month 6	Change from baseline in serum parathyroid hormone concentration, measured in pg/mL, at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value.	Baseline, Month 3, and Month 6
Change From Baseline in Serum 1,25-Dihydroxyvitamin D Concentration at Month 3 and Month 6	Change from baseline in serum 1,25-dihydroxyvitamin D concentration, measured in pg/mL, at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value.	baseline , Month 3, Month 6
Number of Participants With Hypercalcemia During the 6-Month Study Period	Number and percentage of participants who develop hypercalcemia during the 6-month study period. Hypercalcemia is defined as albumin-corrected serum calcium above the age-specific upper limit of normal according to the study laboratory reference range.	Baseline to Month 6
Change From Baseline in Pediatric End-Stage Liver Disease Score at Month 3 and Month 6	Change from baseline in the Pediatric End-Stage Liver Disease (PELD) score at Month 3 and Month 6. The PELD score is calculated using serum bilirubin, international normalized ratio, serum albumin, age less than 1 year, and growth failure. The PELD score has no fixed absolute minimum or maximum possible value and may range from negative to positive values. Higher scores indicate more severe liver disease and a higher risk of short-term mortality/transplant priority.	Baseline, Month 3, and Month 6
Change From Baseline in Serum Alanine Aminotransferase Concentration at Month 3 and Month 6	Change from baseline in serum alanine aminotransferase (ALT) concentration, measured in U/L, at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value.	Baseline, Month 3, and Month 6
Change From Baseline in Serum Aspartate Aminotransferase Concentration at Month 3 and Month 6	Change from baseline in serum aspartate aminotransferase (AST) concentration, measured in U/L, at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value.	Baseline, Month 3, and Month 6
Change From Baseline in Serum Alkaline Phosphatase Concentration at Month 3 and Month 6	Change from baseline in serum alkaline phosphatase concentration, measured in U/L, at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value.	Baseline, Month 3, and Month 6
Change From Baseline in Serum Total Bilirubin Concentration at Month 3 and Month 6	Change from baseline in serum total bilirubin concentration, measured in mg/dL, at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value.	Baseline, Month 3, and Month 6
Change From Baseline in Serum Direct Bilirubin Concentration at Month 3 and Month 6	Change from baseline in serum direct bilirubin concentration, measured in mg/dL, at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value.	Baseline, Month 3, and Month 6
Change From Baseline in International Normalized Ratio at Month 3 and Month 6	Change from baseline in international normalized ratio (INR) at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value. Higher INR values indicate worse coagulation function.	Baseline, Month 3, and Month 6
Change From Baseline in Serum Albumin Concentration at Month 3 and Month 6	Change from baseline in Serum Albumin Concentration at Month 3 and Month 6. The change will be calculated as the follow-up value minus the baseline value. Lower serum albumin values indicate worse hepatic synthetic function.	Baseline, Month 3, and Month 6

Collaborators and Investigators

• Sponsor: Chulalongkorn University

Study record dates

Study Major Dates

• Study Start (Actual): April 28, 2026
• Primary Completion (Estimated): July 10, 2026
• Study Completion (Estimated): April 20, 2027

Study Registration Dates

• First Submitted: June 22, 2026
• First Submitted That Met QC Criteria: June 22, 2026
• First Posted (Actual): June 26, 2026

Study Record Updates

• Last Update Posted (Actual): July 9, 2026
• Last Update Submitted That Met QC Criteria: July 7, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: pediatrics; vitamin d deficiency; cholestasis; Calcitriol; 25-Hydroxyvitamin D2
• Additional Relevant MeSH Terms: Nutrition Disorders; Digestive System Diseases; Biliary Tract Diseases; Bile Duct Diseases; Avitaminosis; Deficiency Diseases; Malnutrition; Nutritional and Metabolic Diseases; Vitamin D Deficiency; Cholestasis; Lipids; Polycyclic Compounds; Steroids; Fused-Ring Compounds; Cholestenes; Cholestanes; Sterols; Vitamin D; Secosteroids; Membrane Lipids; Hydroxycholecalciferols; Cholecalciferol; Dihydroxycholecalciferols; Ergocalciferols; Calcitriol
• Other Study ID Numbers: 0947/68

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No