COPENHAGEN — , results of a randomized, controlled trial suggest. In addition, cholecalciferol had a favorable safety profile and was well tolerated.
“These data support high-dose vitamin D supplementation in early MS and make vitamin D the best candidate for add-on therapy evaluation in the therapeutic strategy for multiple sclerosis [MS],” said study author Eric Thouvenot, MD, PhD, University Hospital of Nimes, Neurology Department, Nimes, France.
The study was presented at the 2024 ECTRIMS annual meeting.
Vitamin D Supplementation Versus Placebo
Research shows vitamin D deficiency is a risk factor for MS. However, results of previous research investigating vitamin D supplementation in MS, with different regimens and durations, have been contradictory.
The current double-blind study included 303 adults newly diagnosed with CIS (within 90 days) and a serum 25-hydroxy vitamin D concentration of less than 100 nmol/L at baseline. Participants had a median age of 34 years, and 70% were women.
About one third of participants had optic neuritis, two thirds had oligoclonal bands from cerebrospinal fluid analysis, and the median Expanded Disability Status Scale (EDSS) score was 1.0. Of the total, 89% fulfilled 2017 McDonald criteria for the diagnosis of relapsing-remitting MS (RRMS).
Participants were randomly assigned to receive high-dose (100,000 international units) oral cholecalciferol or placebo every 2 weeks for 24 months. Participants had a clinical visit at 3, 6, 12, 18, and 24 months, and brain and spinal cord MRI with and without gadolinium at 3, 12, and 24 months.
The primary outcome was occurrence of disease activity — relapse, new or enlarging T2 lesions, and presence of contrast-enhancing lesions.
Significant Difference
During follow-up, 60.3% in the vitamin group showed evidence of disease activity versus 74.1% in the placebo group (hazard ratio [HR], 0.66; 95% CI, 0.50-0.87; P = .004). In addition, the median time to evidence of disease activity was 432 days in the vitamin D group versus 224 days in the placebo group (P = .003).
“As you can see, the difference is really, really significant,” said Dr. Thouvenot, referring to a Kaplan-Meier curve. He said he was somewhat surprised by the “very rapid” effect of vitamin D.
He noted that the 34% reduction in relative risk for disease activity is “similar to that of some published platform therapies for CIS patients.”
An analysis of the 247 patients who met 2017 McDonald criteria for RRMS at baseline showed the same results.
Secondary analyses showed no significant reduction in relapses and no significant differences for annual change in EDSS, quality of life, fatigue, anxiety, or depression.
Additional analyses showed the HR was unchanged after adjusting for known prognostic factors including age, sex, number of lesions (< 9 vs ≥ 9), EDSS score at baseline, and delay between CIS and treatment onset.
Results showed vitamin D3 supplementation was safe and well tolerated. Dr. Thouvenot noted that 95% of participants completed the trial, and none of the 33 severe adverse events in 30 patients suggested hypercalcemia or were related to the study drug.
These encouraging new data support further studies of high-dose vitamin D supplementation as an add-on therapy in early MS, said Dr. Thouvenot. He noted that animal models suggest vitamin D added to interferon beta has a synergistic effect on the immune system.