Results from a small pilot study indicated that high-dose vitamin D supplementation is safe and tolerable in patients with multiple sclerosis (MS), and that it can reduce the presence of autoimmunity-causing immune T cells. Patients are now being recruited for a larger clinical trial. The study, entitled “Safety and immunologic effects of high- vs low-dose cholecalciferol in multiple sclerosis” and was published in the journal Neurology.
Growing scientific evidence indicates that vitamin D plays an important role in MS. Reduced levels of vitamin D, possibly due to low sun exposure, are being investigated as a risk factor for the disease. And the vitamin’s beneficial effect has been observed in mice with experimental autoimmune encephalomyelitis (EAE), an MS-like disease, leading researchers to believe that vitamin D may have a protective effect against autoimmune diseases such as MS.
According to a news release from the National MS Society, scientists aimed to characterize and compare the effects of low- and high-dose vitamin D supplementation in 40 patients with relapsing-remitting MS (RRMS), the most common type of MS. This small pilot study, carried out by a team at Johns Hopkins University, was also undertaken to determine whether a large-scale study on the subject was justifiable and needed.
Patients were randomized to be given either 800 IU (low dose) or 10,400 IU (high dose) of vitamin D daily for six months (vitamin D supplementation is usually 600 IU). Blood tests were performed at three and six months to assess if the supplementation led to an increase in vitamin D blood levels and any immune system effects. Moreover, calcium levels were measured in the blood and urine of patients, since the excess of calcium is a known side effect of vitamin D supplementation. The study’s primary endpoints were the evaluation of the safety, tolerability, and potential immunomodulatory effects of high-dose vitamin D supplementation.
Results showed that, as expected, vitamin D blood levels were high in the high-dose group, reaching the optimal therapeutic level. Furthermore, Th17 cells, believed to be a major player in the autoimmunity observed in MS, were reduced in the high-dose group only, and a positive correlation between higher levels of vitamin D and a greater reduction in these immune cells was established. Few minor adverse advents were observed, with no significant differences between dose groups.
The study, too small for the observation of disease activity modification, will now be followed by a larger clinical trial, sponsored by an MS Society research grant. The team aims to recruit 172 patients and compare vitamin D supplementation at 600 IU or 5,000 IU, as an addition to therapy with glatiramer acetate (Copaxone®). More information on the clinical trial and how to participate is available through this link (NCT01490502).
MS is a debilitating disease in which immune cells attack the central nervous system (CNS), namely nerve fibers and myelin, the element that covers and protects nerve cells. Its onset is believed to be caused by several genetic and environmental factors.