Adding Vitamin D May Amplify This MS Drug’s Clinical Benefit

VANCOUVER, BC—Vitamin D may be an affordable and safe way to boost the therapeutic benefits of interferon-β (IFN-β) in patients with multiple sclerosis (MS), according to a new study presented at the 68^th AAN Annual Meeting.

Previous research has studied various relationships between serum vitamin D levels and IFN-β therapy and the effects on relapses, MRI lesions, and disability. Researchers from the University of Chicago, Chicago, IL, hypothesized that vitamin D would enhance IFN-β signaling. To test this hypothesis, they studied in vitro intracellular interferon responses to combinations of IFN-β-1b and vitamin D in a “well-characterized MS cohort.” They incubated mononuclear cells (MNC) in vitro with 160U/mL IFN-β-1b for 30min to 48h ± 100–200nM vitamin D from an array of therapy-naïve MS patients: stable RRMS (n=29), active RRMS (n=11), SPMS (n=14), progressive MS (n=8), plus MS patients receiving IFN-β or glatiramer treatment, as well as healthy controls (n=26).

The researchers measured cytokines, IFN-responsive transcription factor, p-Y-STAT1, and MxA protein in the cells when incubated in vitro.

Xuan Feng, PhD, the study’s lead author, reported that vitamin D enhanced IFN-β-1b activation of STAT1 by 30-70% in untreated patients, and by 30–150% in IFN-treated patients. For most forms of MS, supplementation with vitamin D showed a benefit even when serum vitamin D was high. 

Study findings indicate increased interferon signaling may “provide a mechanism for benefits of vitamin D in preventing and ameliorating MS, before and during IFN-β therapy,” added Dr. Feng. Moreover, vitamin D may help treat the effects of low intrinsic serum IFN-α/β levels in patients with MS.