Impact of Vitamin D Therapy on Thyroid Function and Antibody Levels in Pediatric Graves' Disease

NCT07369063 | Recruiting Phase 2 DMC FDA Drug

• 1 other identifier: 25-0285
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this randomized pilot feasibility clinical trial is to determine the feasibility of implementing a protocol for a larger trial to assess the effects of high-dose vitamin D supplementation in pediatric patients (9-17 years old) newly diagnosed with Graves' disease. The main questions it aims to answer are: What are the recruitment and adherence rates for a larger trial using this protocol? Is the data collection process complete and robust enough for a larger trial? What are the potential barriers to implementing a larger-scale trial? Researchers will compare vitamin D supplementation plus standard methimazole therapy to methimazole therapy alone (with participants permitted to take up to 1000 International Units of vitamin D2 daily) to explore potential effects on thyroid hormone and antibody levels. Participants will: Be randomized to either the intervention or control group. Take study medications (vitamin D or placebo) as directed. Attend regular study visits for blood tests and clinical assessments. Complete medication logs.

Conditions

Graves' Disease; Hyperthyroidism

Keywords

vitamin d; graves disease; hyperthyroidism

Outcome Measures

Primary Outcomes (4)

• Feasibility Metrics: Recruitment Rate

  Percentage of eligible participants approached who consent to participate in the study. This metric will assess the efficiency of recruitment strategies.

  through study completion, an average of 1 yea

• Feasibility Metrics: Adherence Rate

  Percentage of prescribed vitamin D doses taken by participants in the intervention arm. Adherence will be tracked via pill counts and participant self-report.

  From enrollment to 24 week/6month follow up visit

• Feasibility Metrics: Data Completeness

  Percentage of completed data fields for key outcome measures (thyroid function tests, TSI levels, etc.). This will assess the quality and completeness of data collection.

  From baseline data collection to the 24-week/6-month follow-up visit.

• Feasibility Metrics: Implementation Barriers

  A qualitative assessment of any challenges encountered during the study implementation (e.g., recruitment difficulties, adherence issues, logistical problems). This assessment will inform strategies for overcoming these barriers in a future, larger-scale RCT.

  through study completion, an average of 1 year

Secondary Outcomes (1)

• Time to Normalization and Thyroid function Trends

  from enrollment to 24 week/6month follow up visit

Other Outcomes (1)

• Change in TRAb and TSI Levels

  from enrollment to 24 week/6month visit

Study Arms (2)

High-Dose Vitamin D2 + Methimazole

EXPERIMENTAL

Participants in this arm will receive methimazole at a dose determined by their treating physician, according to standard clinical practice guidelines for pediatric Graves' disease. In addition, they will receive high-dose vitamin D2 (ergocalciferol) 50,000 IU orally weekly for the first 8 weeks, followed by 50,000 IU orally every two weeks for the remaining 16 weeks of the study.

Drug: Ergocalciferol 50,000 IU; Drug: Methimazole

Methimazole (with optional low dose Vitamin D2)

PLACEBO COMPARATOR

Participants in this arm will receive methimazole at a dose determined by their treating physician, according to standard clinical practice guidelines for pediatric Graves' disease. Participants will have the option of taking up to 1000 IU of vitamin D2 daily, purchased over-the-counter, but this will not be provided by the study. This is to address potential vitamin D deficiency while maintaining a comparison group.

Drug: Methimazole

Interventions

Ergocalciferol 50,000 IU DRUG

Participants will receive ergocalciferol 50,000 IU oral capsules weekly for the first 8 weeks, followed by 50,000 IU every two weeks for the subsequent 16 weeks (total 24 weeks).

High-Dose Vitamin D2 + Methimazole

Methimazole DRUG

Methimazole is considered standard of care for pediatric Graves' disease. Dosing is determined and adjusted by the participant's treating physician

High-Dose Vitamin D2 + Methimazole; Methimazole (with optional low dose Vitamin D2)

Eligibility Criteria

• Age: 9 Years - 17 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• All new pediatric participants aged 9-17 years with a new diagnosis of GD who will be started on methimazole, will be offered to participate at the time of diagnosis.
• Biochemical features include:
• Suppressed TSH \<0.1.
• Elevated T3
• Elevated Free T4
• Elevated T4
• Positive TSI or TRAb. The presence of antibodies is diagnostic.
• Our study will offer enrollment to non-English speaking participants

You may not qualify if:

• Initial hydroxy vitamin D levels \>80 ng/mL
• Hypocalcemia, corrected calcium based on albumin \<8.4 mg/dL
• Hypercalcemia, corrected calcium based on albumin \>10.5 mg/dL
• Conditions that affect vitamin D metabolism such as: malabsorption, chronic kidney or liver disease, nephrocalcinosis, hyperparathyroidism
• Current use of medications which are known to affect thyroid function or vitamin D metabolism such as thyroid hormone replacement, corticosteroids, anticonvulsants
• Allergy to vitamin D or methimazole
• Diagnosis of Hashitoxicosis or thyrotoxicosis (both TSH receptor antibody (TRAb) and thyroid-stimulating immunoglobulin (TSI) levels are negative)
• Participants under the age of 9 years at the time of diagnosis
• Pregnant participants
• Active or uncontrolled infections, other significant medical conditions deemed by the investigator to interfere with study participation or pose undue risk to the participant.

Sponsors & Collaborators

• Northwell Health: lead

Study Sites (1)

Pediatric Endocrinology at Northwell Health

New Hyde Park, New York, 11042, United States

RECRUITING

MeSH Terms

Conditions

Graves Disease; Hyperthyroidism

Interventions

Ergocalciferols; Methimazole

Condition Hierarchy (Ancestors)

Exophthalmos; Orbital Diseases; Eye Diseases; Goiter; Thyroid Diseases; Endocrine System Diseases; Autoimmune Diseases; Immune System Diseases

Intervention Hierarchy (Ancestors)

Cholestenes; Cholestanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Sterols; Vitamin D; Secosteroids; Membrane Lipids; Lipids; Sulfhydryl Compounds; Sulfur Compounds; Organic Chemicals; Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Study Officials

• Sharon Hyman, MD

  Northwell Health

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Sharon Hyman, MD

CONTACT

15164723750; Shyman1@northwell.edu

Sofya Ilmer, MD

CONTACT

5164723750; silmer@northwell.edu

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: The control group receives standard methimazole therapy and has the option of taking up to 1000 IU/day of over-the-counter vitamin D2, which is not provided by the study. This is to ensure ethical considerations related to vitamin D deficiency are met while maintaining a comparison group. Should the patients in the control group have vitamin D levels \<20 ng/mL, patients will be strongly advised to take the 1000 IU of vitamin D daily for repletion.

Study Record Dates

• First Submitted: July 14, 2025
• First Posted: January 27, 2026
• Study Start: August 1, 2025
• Primary Completion (Estimated): February 28, 2027
• Study Completion (Estimated): February 28, 2027
• Last Updated: January 27, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP
• Time Frame: Data sharing will be considered upon acceptance of the manuscript for publication in a peer-reviewed journal.
• Access Criteria: Researchers may request access to the de-identified individual participant data by contacting Dr Sharon Hyman or Dr Sofya Ilmer. Requests will be reviewed based on scientific merit, adherence to data use agreements, and capacity to protect participant confidentiality. A data use agreement will be required. Data will be shared in a format compliant with relevant privacy regulations (e.g., HIPAA).

Locations

US (1)