A Phase II Trial on the Effect of Low-Dose versus High-Dose Vitamin D Supplementation on Bone Mass in Adults with Neurofibromatosis 1 (NF1)

Principal Investigator: VISKOCHIL, DAVID H
Institution Receiving Award: UTAH, UNIVERSITY OF
Program: NFRP
Proposal Number: NF110055
Award Number: W81XWH-12-1-0487
Funding Mechanism: Clinical Trial Award
Partnering Awards:
Award Amount: $1,022,082.00


This is a study to determine the best dose of vitamin D to supplement adults with neurofibromatosis type 1 (NF1) who have a vitamin D insufficiency. Usually, skin exposure to ultraviolet radiation is ample for adequate levels of vitamin D. However, for those who need supplementation, the usual dose is 600 IU of vitamin D3 orally per day. Individuals with NF1 have lower 25-hydroxy vitamin D levels than the unaffected population, and they tend to have osteopenia (low bone mineral density), even at relatively young ages. Thus, this study will determine if higher daily doses of vitamin D3 (4,000 IU) lead to preservation of bone mineral density in both men and women between 25 and 40 years of age who have NF1.

The doses selected for this study have minimal risks; nevertheless, participants will be monitored for adverse events and vitamin D toxicity. Such toxicity could be secondary to inadvertent dosing and primarily causes symptoms associated with high serum calcium levels. The potential benefits of this study include preservation of bone mineral density and improved well-being.

The potential contribution of results from this clinical trial rests primarily with patient care. The underlying mechanisms by which increased vitamin D3 supplementation could benefit bone mineral density and improved well-being are not evaluated in this trial. However, participants have an option to store their serum samples for future studies that could evaluate various aspects of bone health related to calcium and vitamin D influences. These de-identified samples could be retrieved from a biospecimen repository by investigator request for additional research studies.