Recruiting

Phase 2

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

Sponsor:

Northwell Health

Code:

NCT07369063

Conditions

Graves Disease

Graves' Disease

Hyperthyroidism

Eligibility Criteria

Sex: All

Age: 9 - 17

Healthy Volunteers: Not accepted

Interventions

Ergocalciferol 50,000 IU

Methimazole

Study Details

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

Graves' Disease

Hyperthyroidism

Study ID

NCT07369063

Start date

Aug 1, 2025

Status verified date

Jan, 2026

Completion date

Feb 28, 2027

Anticipated

Primary completion date

Feb 28, 2027

Anticipated

Eligibility Criteria

Sex: All

Age: 9 - 17

Healthy Volunteers: Not accepted

Inclusion Criteria:

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

Exclusion Criteria:

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.

Study Design

Enrollment

30 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Other

Interventions and Outcome Measures

Arms

experimental: High-Dose Vitamin D2 + Methimazole

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.

placebo comparator: Methimazole (with optional low dose Vitamin D2)

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.

Interventions

Ergocalciferol 50,000 IU

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).

Methimazole

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

Primary outcome measure

Feasibility Metrics: Recruitment Rate [ Time Frame: through study completion, an average of 1 yea ]
Feasibility Metrics: Adherence Rate [ Time Frame: From enrollment to 24 week/6month follow up visit ]
Feasibility Metrics: Data Completeness [ Time Frame: From baseline data collection to the 24-week/6-month follow-up visit. ]
Feasibility Metrics: Implementation Barriers [ Time Frame: through study completion, an average of 1 year ]

Central Contacts and Locations

Central contacts

Sharon Hyman, MD

15164723750 Shyman1@northwell.edu

Sofya Ilmer, MD

5164723750 silmer@northwell.edu

Locations

Pediatric Endocrinology at Northwell Health

Recruiting

New Hyde Park, New York, United States, 11042

Contacts

Sofya Ilmer, MD

516-472-3750 silmer@northwell.edu

More Information

Sponsor

Northwell Health

Last update posted

Jan 27, 2026

Last verified

Jan, 2026

Keywords

vitamin d
graves disease
hyperthyroidism

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Northwell Health on 2026-01-27.