Clinical trial · Interventional
Vitamin D Supplementation for Adults With Neurofibromatosis Type 1 (NF1)
A Phase II Trial on the Effect of Low-Dose Versus High-Dose Vitamin D Supplementation on Bone Mass in Adults With Neurofibromatosis Type 1 (NF1)
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Why stopped (as posted): unable to enroll
Summary
Brief summary (as posted)
This clinical trial is conducted by one of 4 locations; University of British Columbia (Vancouver, CA), University of Utah (Salt Lake City, UT, USA), University of Cincinnati (Cincinnati, OH, USA), and University of Hamburg (Hamburg, Germany). Adults with NF1 have a higher risk of osteopenia and osteoporosis, a condition of low bone density that can lead to fragile bones and bone breakage. People with NF1 also have lower vitamin D levels than unaffected individuals. Vitamin D is important for normal bone health, but studies to improve bone health by vitamin D supplementation in people with NF1 have not been tried. The purpose of this study is to treat adults with NF1 who have insufficient serum vitamin D levels with 2 different doses of vitamin D supplementation to determine if vitamin D supplementation ameliorates the usual loss of bone mineral density over 2 years.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Neurofibromatosis Type 1 (NF1) | — | UNRESOLVED | — |
Interventions
Interventions (1)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Cholecalciferol | Drug | — | UNRESOLVED |
Design
Arms and outcomes
Arms (2)
- type
- ACTIVE_COMPARATOR
- label
- cholecalciferol 600 IU
- description
- cholecalciferol in Ddrops form at either 600 International units per day versus 4,000 IU per day
- interventionNames
- Drug: Cholecalciferol
- type
- ACTIVE_COMPARATOR
- label
- cholecalciferol 4,000 IU
- description
- Cholecalciferol at 4,000 IU per day in the form of liquid Ddrops
- interventionNames
- Drug: Cholecalciferol
Primary outcomes (1)
- measure
- Bone mineral density
- timeFrame
- Change from Day 1 to 2 years
Eligibility
Eligibility (as posted)
- Sex
- All
- Minimum age
- 25 Years
- Maximum age
- 40 Years
Show eligibility criteria text
Inclusion Criteria: All individuals with NF1 (neurofibromatosis type 1), based on NIH diagnostic criteria, who are between the ages of 25 and 40 years, may participate in this study. All participants will be enrolled in the study and then screened for serum 25(OH)D levels, and all individuals with levels between 9 and 29ng/ml (inclusive) are eligible for vitamin D supplementation - Exclusion Criteria: 1. diagnosis of Paget's disease, hyperthyroidism, hyperparathyroidism, or other medical condition that affects bone health 2. they foresee that they will be unable to comply with the two-year study protocol 3. Pregnant, planning to conceive within the next two years, or is less than 6 months post-delivery or lactation. 4. vitamin D supplementation in the last 3 months equal to or greater than 600IU per day 5. oral or IV glucocorticoid use for over 3 months 6. bisphosphonate therapy for more than 3 months 7. calcitonin therapy for more than 3 months 8. calcium supplementation in last 3 months equal to or greater than 1000mg per day 9. malignant peripheral nerve sheath tumor (MPNST) 10. history of kidney stones in last 5 years 11. individuals with metal instrumentation in spine or hip that preclude accurate DXA interpretation. 12. inability to obtain blood samples on routine venipuncture 13. anti-epileptic medical therapy 14. anticoagulant medical therapy
References
Publications (1)
- BACKGROUNDSchnabel C, Jett K, Friedman JM, Frieling I, Kruse HP, Mautner V. Effect of vitamin D3 treatment on bone density in neurofibromatosis 1 patients: a retrospective clinical study. Joint Bone Spine. 2013 May;80(3):315-9. doi: 10.1016/j.jbspin.2012.07.010. Epub 2012 Sep 26. PMID 23021159